1

Committee members • Tim Knott (Chairperson) • Ida Gilbert (Chairperson to be) • Natasha Mitchell (Joint secretary) • Negar Hamzianpour (Joint secretary) • Helen Appleboam (Hotel and

conference organiser) • Michael Ziglar (International liaison) • David Nutbrown-Hughes (Website and

audio-visual) • Charlie Barton (Disease surveillance

officer) • Rachael Grundon (Scientific

programme) • Christine Heinrich (Scientific

programme) • Chris Dixon (Scientific programme) • Mike Rhodes (Editor) • Jenny Lambert (Clinical auditor) • Rob Lowe/Alistair Oldfield

(Treasurer) Publisher British Association of Veterinary Ophthalmologists. Enquiries should be directed to Mike Rhodes, Willows Referral Service, Highlands Road, Shirley, Solihull, West Midlands, B90 4NH. Tel: 0121 712 7070. Email: Mike@focusreferrals.co.uk Membership information Full membership is open to veterinary surgeons with an interest in the field of ophthalmology. Associate membership is open to those with professional interest in the field of ophthalmology. Membership is for 12 months and starts on 1st April. Membership fees are £40 per year. Abstracts / lecture notes submission Please follow the guidelines below: • The first line should give the title. • The authors’ names should appear on

the next line – initials followed by last name.

• Provide the name of your practice / institution.

• Use single spacing. • Use 10 point Trebuchet MS font for all

text. • Photographs or diagrams are

encouraged, but do not place them within the main body text. Instead

send each photograph or diagram as a separate JPEG image with a title such as ‘Figure 1: The eye before surgery’. Up to four images may be included. If additional images are required, please discuss this in advance of the deadline.

• The abstract should be 500-1000 words.

• Please send in electronic format to Mike@focusreferrals.co.uk

Deadlines Deadlines will be published on the website but are usually the first day of the month, two months prior to the meeting. Abstracts will be reviewed and the author notified one week after the submission deadline with time allowed for alterations if required. Twelve minutes will be allocated for each presentation, with a further three minutes for discussion. All oral presentations must be made in English. Presentations must be compatible with Microsoft PowerPoint 2003. Copyright and Photocopying © British Association of Veterinary Ophthalmologists 2017. All rights reserved. No part of this publication may be produced, stored or transmitted in any form or means without the prior permission in writing from the copyright holder. Advertising Enquiries about advertising should be directed to the Editor. Copies need to be received one month prior to the meeting for inclusion in the proceedings. Disclaimer The Publisher, the British Association of Veterinary Ophthalmologists and the Editor cannot be held responsible for errors or any consequences arising from the use of material contained in this journal. The views and opinions expressed do not necessarily reflect those of the Publisher or Editor; neither does publication of advertisements constitute any endorsement by the Publisher or the Editor of the products advertised.

2

SPEAKER BIOGRAPHIES

Chris Dixon BVSc Cert. VOphthal MRCVS

RCVS Advanced Practitioner in Veterinary Ophthalmology

Chris graduated from the University of Bristol and spent several years working in first opinion mixed practice in the North Yorkshire Moors and Cumbria. During his time at the University of Bristol Chris was lucky enough to be mentored by Professor Sheila Crispin, and this tuition inspired a persistent interest in ophthalmology. Early in his veterinary career, Chris decided to focus on ophthalmology due to the exciting mixture of microsurgery and medicine, and attained the RCVS postgraduate certificate. In 2010 Chris joined fellow ophthalmologist Gary Lewin, and in 2012 they formed Veterinary Vision, a dedicated ophthalmology referral practice based in Penrith, Cumbria. Chris has presented clinical research at national and international veterinary ophthalmology conferences, and has a particular interest in topographical analysis of the cornea and retinal reattachment surgery.

Jo Wolfer DVM ACVO

DVM Ontario Veterinary College, University of Guelph 1988 Internship Western College of Veterinary Medicine, Saskatoon, 1989 Residency in ophthalmology Ontario Veterinary College 1990-1992

American College of Veterinary Ophthalmologists 1994

American Society of Retina Specialists

3

Mr Malcolm Woodcock Consultant Ophthalmic Surgeon

BM MSc DAvMed MRCOphth FRCS(Ed)

Malcolm Woodcock is a consultant ophthalmologist and vitreoretinal surgeon who carries out his NHS work at Worcestershire Acute Hospitals NHS Trust. He set up and runs the vitreoretinal (VR) service in Worcestershire and is part of the wider regional vitreoretinal service based at the Birmingham and Midland Eye Centre (BMEC) at City Hospital in Birmingham. He is the nominated specialist in the Worcestershire for the referral cataract cases that have had complications and require further treatment. He specialises in the surgical treatment of complex cataracts as well as doing a high volume of routine cataract surgery himself. Mr. Woodcock also carries out a high volume of retinal surgery including macular hole repairs, peeling epiretinal membranes and retinal detachment repairs. In addition to his vitreoretinal work Mr. Woodcock is also a specialist in aviation medicine and from 2007 until 2014 was the head of Aviation Ophthalmology for the 3 armed Services (Fleet Air Arm, Army Air Corps and RAF). Mr. Woodcock speaks widely on ophthalmology and vitreoretinal surgery to other doctors and professional groups including optometrists, GPs and military medial officers. He also lectures on aviation ophthalmology regularly at the Royal Air Force's Centre for Aviation Medicine and King's College London, in particular on its internationally renowned Diploma of Aviation Medicine course. He has also been involved in teaching and lecturing to medical students at the universities of Cambridge, Birmingham, Cape Town and UCL. Mr. Woodcock has very active research interests with active collaboration with Moorfields Hospital in London and the Centre of Aviation Medicine at the test and evaluation centre RAF Boscombe Down. He has numerous publications in the medical literature and given many presentations at both national and international meetings. He is a reviewer of papers for 4 international scientific journals in ophthalmology.

4

John Goulding BVMS (Hons) MRCVS

Group Veterinary Advisor INDEPENDENT VETCARE

John Goulding graduated with honours from Glasgow in 1989 and until joining IVC last year, worked at St George’s Veterinary Group in the Midlands. Under his stewardship it grew to become a multisite small animal and equine practice with a team of over 100. He has had articles published on management topics and spoken at several congresses. He is currently a member of the Certification and Training committee of the VPMA. He is particularly interested in maximising the use of computer databases for strategic planning, marketing and analysing performance. He enjoys empowering all team members to work together synergistically.

David Gould BSc(Hons) BVM&S PhD FRCVS DVOphthal DipECVO

RCVS & European Veterinary Specialist in Ophthalmology

David Gould graduated from the University of Edinburgh in 1992 and, after a period in general practice, completed a PhD at the University of Cambridge in the molecular genetics of inherited eye diseases of dogs. Following this he moved to the University of Bristol for a three year clinical residency in veterinary ophthalmology. After this he was appointed Lecturer in Veterinary Ophthalmology at Bristol University Veterinary School, a post that he held for three years before joining Davies Veterinary Specialists in October 2003 to jointly run their ophthalmology service. He holds both RCVS and European Diplomas in Veterinary Ophthalmology and is an RCVS recognised Specialist in Veterinary Ophthalmology and European Veterinary Specialist in Ophthalmology. David was awarded Fellowship of the Royal College of Veterinary Surgeons for Meritorious Contributions to Clinical Practice (MCCP) in 2017.

5

Claudia Hartley

BVSc CertVOphthal DipECVO MRCVS

European & RCVS Specialist in Veterinary Ophthalmology

Claudia graduated from the University of Bristol in 1995, and worked in first opinion practice in both farm animal and small animal practices for nine years. During this period she gained her RCVS Certificate in Veterinary Ophthalmology, which tempted her into a residency at the Animal Health Trust (AHT) in 2004. She gained her European Diploma in Veterinary Ophthalmology in 2007. Claudia became head of the AHT unit of Comparative Veterinary Ophthalmology in 2009, and then moved to Davies Veterinary Specialists in 2015. Since March 2017 Claudia has been head of Ophthalmology at Langford Veterinary Services, Bristol Veterinary School.

Claudia is particularly interested in ophthalmic surgery and treatment of wild or zoological species with ophthalmic problems. She has worked with a number of international charities worldwide to alleviate ocular discomfort and treat visual impairment. Claudia loves working as part of a team of highly qualified and dedicated specialists at Langford Veterinary Services, and teaching both undergraduate and postgraduate veterinary nurses and surgeons.

Charlotte Dawson BVetMed MVetMed DipECVO MRCVS

Lecturer in Veterinary Ophthalmology at the RVC

Hello, I am Charlotte and I graduated from the RVC in 2009. After a short period in private practice I undertook two rotating internships (one in private practice and one at the RVC). I then continued with a residency and am now a lecturer at the RVC. I enjoy all aspects of life working at a university including the clinical activities, teaching and research. In my spare time I like spending time with my family, friends and traveling with my dog Frank.

Introduction to canine vitreo-retinal surgery A U.K. Perspective

Chris Dixon Veterinary Vision cdixon@veterinaryvision.co.uk 01768 877255 Before embarking on vitreo-retinal surgery, the surgeon should have a comprehensive understanding of the posterior segment anatomy and surgical techniques involved. These notes are only a very brief overview and I would highly recommend reading Chapter 25 ‘Surgery of the Canine Posterior Segment’ by Vaninisi S., Wolfer J., and Hoffman A. In Veterinary Ophthalmology 5th Edition., Ed. Gelatt, Gilger, Kern. Anatomy Interface between the vitreous and retina is the posterior vitreal membrane - Relatively weak except at the pars plana retinae and optic disk - Collagen fibrillar insertions link into the internal limiting membrane of the retina

Potential space exists between the neurosensory retina and retinal pigment epithelium

Vitreal conditions to consider - Persistent of the primary hyaloid vasculature - Vitreal syneresis - Asteroid hyalosis - Vitreal haemorrhage - Prolapsed vitreous into the anterior segment

Classification of retinal detachment Partial or complete Rhegmatogenous (tear / hole) or non-rhegmatogenous Rhegmatogenous Primary – spontaneous preceded by a change in the vitreous Secondary – related to trauma, glaucoma, inflammatory disease, surgery Non-rhegmatogenous Bullous - Serous - Exudative - Haemorrhagic

Traction - band or membrane formation Congenital Vitreal surgery includes - Vitreal paracentesis (hyalocentesis) - Anterior vitrectomy (anterior chamber and trans-pupillary) - Complete vitrectomy (Pars plana)

Vitreal paracentesis Collection of a vitreal sample for laboratory analysis - Preoperative mydriasis - General anaesthesia - Careful preparation with iodine solution - Measure 6mm from the dorsal limbus - Penetrate a 23G needle into the vitreal body aiming at the posterior pole - Can only aspirate liquefied vitreous – limit to 0.1ml Potential Complications include: - Lens touch / lens capsule rupture – cataract formation / lens induced uveitis - Haemorrhage - Retinal hole – retinal detachment - Contamination – vitritis / endophthalmitis

Same technique can be used for the delivery of medication into the vitreous Anterior Vitrectomy Often performed during lendectomy Herniated vitreous around disrupted lens zonule fibres e.g. lens subluxation / luxation Prolapsed vitreal filaments during planned or unplanned posterior capsulotomy Planned anterior vitrectomy for excision of persistent hyperplastic primary vitreous, malignant glaucoma, removal of a foreign body, removal of lens fragments Instrumentation - Micro-intraocular instruments - Vitreous / ONG / Vannus scissors, cyclodialysis spatula and

cellulose spears - Anterior vitrector with the phacoemulsification machine (electric / pneumatic)

Aim to keep all vitreous posterior to the pupil Vitreal filaments can serve as a scaffold for inflammatory membrane formation +/- traction bands Vitreous in contact with corneal endothelium will result in persistent oedema Potential for occlusion to aqueous outflow – glaucoumatous pressure spike Complete Vitrectomy Indications include: - Rhegmatogenous retinal detachment - Removal of vitreous traction bands - Removal of foreign bodies - Vitritis, vitreal opacification, haemorrhage - Malignant glaucoma

Veterinary VR surgery has been performed since the 1970’s so why are there so few clinics offering this service globally? - Very high set-up costs (e.g. VR machine

£80k+, BIOM, invertor, and laser filter £20k) - High consumable costs - Time-consuming training - Excellent bi-manual dexterity required

Surgical Anatomy Multiple (usually three) sclerotomies through the pars plana ciliaris - I.e. between the end of the anterior pars

plicata and the ora ciliaris - Do not want to puncture the ciliary body or

retina - Width of the pars plana varies by quadrant

Smith et al measurement from the limbus Sullivan et al measurement from the limbus - Dorsolateral 6mm - dorsal quadrant, 9.25 +/- 0.81 mm - Dorsomedial 5mm - medial quadrant, 5.30 +/- 0.77 mm - Ventromedial 7mm - ventral quadrant, 7.18 +/- 0.89 mm - Ventrolateral 9mm - lateral quadrant, 9.41 +/- 0.79 mm

Vasculature to consider: - Intrascleral plexus ‘circle of Hovius’, drains aqueous humor – 4-5mm posterior to the limbus

and 3-4mm wide - Vortex veins exit each quadrant at the equator - Long posterior ciliary arteries and veins (branches of the external ophthalmic artery and vein) –

3 o’clock and 9o’clock position

The interface between the neurosensory retina and vitreous is critical in the development of rhegmatogenous retinal detachment. Liquification of the vitreous allows for counter-current motion over the retinal surface with ocular movement. Turbulence within the posterior segment can lead to tearing especially if there is pre-existing retinal atrophy or a retinal hole. It has been reported that dogs with a tendency to violently shake their heads are more likely to develop a spontaneous giant retinal tear – Vainisi S., Wolfer J. 2004 Veterinary Ophthalmology. It is thought that Shih Tzu, Boston Terrier, Toy and Minature Poodles develop vitreal degeneration leading to syneresis. In the population of dogs that I have seen at our clinic, Shih Tzu’s are over-represented.

In humans the central ‘nucleus’ of the vitreous is semi-fluid and the peripheral ‘cortex’ has increased density. In our canine patients, the nucleus has increased density compared to the cortex. Proliferative vitreoretinopathy (PVR) is the growth of cellular membranes in contact with the neurosensory retina. Contraction of the membranes results in detachment of the neurosensory retina and immobilization. PVR has been reported by Blair et al 1985 in Labradors with oculoskeletal dysplasia. We have seen PVR in our clinic with a spectrum of severity. It is not uncommon for the detection of a membrane without retinal distortion, and occasionally we encounter the ‘clam shell’ fixed in position. Equipment required for high-speed posterior vitrectomy for retinal detachment: Microscope with suitable head for posterior segment surgery accessory attachment BIOM / EIBOS non-contact wide-view lens system to visualise the posterior segment Invertor, manual vs automatic Microscope laser filter Phacoemulsification unit High speed (6000+ cuts/min) VR unit Laser 810nm vs 532nm generator with endoprobe Anterior segment and posterior segment instruments

Steps in retinal reattachment surgery (giant tear) 1. Remove lens / cataract by small port phacoemulsification 2. Insertion of a prosthetic IOL 3. Careful closure of the corneal incisions 4. Peritomy 5. One-stepped 23G self-sealing trocar insertion 6. Core vitrectomy (2500 cut) 7. Triamcinolone acetonide 8. High-speed (6000+) low vacuum vitrectomy 9. Reposition retina (peel membranes if required) 10. Heavy liquid perfluro-n-octane 11. Laser retinopexy 12. Heavy liquid – air exchange 13. Laser again if required 14. Silicone oil infusion 15. Remove trocars and suture port closed 16. Close lateral canthotomy

Silicone Oil - 5000 centistoke with a specific gravity of 0.971 forms a buoyant viscous bubble - In humans silicone oil is normally removed after 3-6 months, but generally life-long in dogs

Barrier retinopexy / prophylactic retinopexy Trans-pupillary approach with clear visualisation – can use a scleral depressor Indirect headset (£6k-12k) with modified optics for the laser generator Endo approach through posterior capsulotomy ‘Seal’ around small tears and holes Prophylactic therapy for ‘at-risk’ breeds and ‘fellow eyes’ Please feel free to contact me if you have a question regarding VR surgery or if you have a case which you wish to discuss

Rhomboid blepharoplasty and cryotherapy for the treatment of a squamous cell carcinoma on the lower eyelid in a horse E. C. Jeanes (AHT), S. Koll (RVC), C. Dawson (RVC), B. Dunkel (RVC) and R. Tetas Pont (RVC). A 9-year-old grey Irish Draught horse gelding was presented to the Royal Veterinary College for excision of a medial lower eyelid squamous cell carcinoma. The diagnosis had been made 18 days previously using a fine needle aspirate by the referring veterinary surgeon. The 10mm x 12mm tumour was resected en-bloc under general anaesthetic. This was done using full thickness cuts of equal length medial, lateral and ventral to the mass, so that a square of tissue was removed. The cuts were made 5mm from the edge of the mass. The wound edges were treated with liquid nitrogen cryotherapy. Two freeze-thaw cycles were used of 10 seconds freezing then 60 seconds melting. Reconstruction of the lower eyelid was achieved using a rhomboid blepharoplasty. An incision was made extending ventro-medially from the ventromedial aspect of the excision site. This incision was the same length as the previous incisions. A proximal vertical incision was then made from the ventromedial edge of the last incision to create a rhomboid shaped skin graft. Blunt dissection was used to undermine the rhomboid graft and the skin medial to the graft to mobilise the tissue. The rhomboid graft was swung dorsally and laterally to fill the eyelid defect. The wound was closed using routine subcutaneous and dermal sutures. Clean margins were achieved with the surgery and the surgical wounds healed well with no complications. In the follow-up period of six months, no recurrence of the tumour was noted. Squamous cell carcinoma (SCC) is the most common tumour of the equine orbit and adnexa and the second most common tumour in the horse overall. The incidence of ocular SCC in equines is positively correlated with increased exposure to ultraviolet light. Lack of skin pigmentation also increases the risk of becoming affected. Ocular SCCs are typically highly locally invasive but the reported metastatic rate is low. Eyelid SCC has been shown to carry a poorer prognosis compared to other ocular locations. The mainstay of treatment of eyelid SCC is surgical excision. Recurrence after surgical excision is likely, particularly if clear surgical margins cannot be achieved. The recurrence rate reported varies and adjuvant therapy, such as cryotherapy, radiofrequency hyperthermia, radiotherapy, topical and intralesional chemotherapy with cisplatin or 5-fluorouracil, bacille Calmette-Guerin (BCG) cell wall extract, and carbon dioxide laser ablation is often considered to avoid further recurrences. Blepharoplasties in horses are rarely reported in the literature due to the challenges of the poorly mobile tissue around the horse eye; subsequently enucleation or exenteration may be required at the expense of a visual eye. The rhomboid blepharoplasty allows closure of a large eyelid defect using haired skin. After a rhomboid graft is performed, the retraction force vectors are expected to be directed alongside the palpebral fissure. This may be an advantage compared to other blepharoplasties, for example an H-plasty, where these vectors are expected to develop perpendicularly to the palpebral fissure and potentially predispose to post-operative ectropion and lagophthalmus. The surgeons prioritized not altering the lateral canthus and the normal lateral part of the lower eyelid. The advantage achieved with the rhomboid technique is that the cornea is shielded by the nictitans membrane from trichiasis, thus minimizing the risk of post-operative corneal irritation. Furthermore, if excision of a tumour is later shown to be incomplete on histopathology, sparing the lateral canthus would allow a sliding lateral blepharoplasty to be performed at a later date. This case demonstrates that a rhomboid blepharoplasty can be used to achieve functional and cosmetic eyelid reconstruction at the medial canthus in the horse.

AN INVESTIGATION INTO THE BACTERIAL CONTAMINATION OF GONIOLENSES IN USE IN CLINICAL

PRACTICE.

RA Grundon¹, EJ Scurrell², J Mould¹, E Hayton-Lee¹, CL Heinrich¹

1 The Eye Vet Clinic, Marlbrook, Herefordshire, UK

2 CytoPath Ltd, Ledbury, Herefordshire, UK

Purpose - To report the incidence and evaluate the clinical significance of goniolens bacterial

contamination in clinical use.

Methods - Three groups of twenty dogs undergoing gonioscopy in the UK had goniolenses swabbed

for bacteriology culture and identification prior to placement on the cornea. Three protocols of

lens use, with 2 different goniolenses (Koeppe and Barkan-lovac), were studied. At the end of data

collection the storage boxes were also swabbed. Telephone follow up was made to assess the

impact of goniolens placement on the dogs. A final group of 21 dogs then had the goniolenses

swabbed before use as before, but with an implemented cleaning protocol after use and before

storage.

Results - Low levels of bacterial contamination were found in all 3 initial groups (10-15%). Seven

positive lens bacterial cultures and one box culture occurred with eight different bacterial species

cultured. No statistical correlation was found between protocol used and rate of contamination,

nor between length of storage between use and contamination. All the bacterial species cultured

were considered commensals in the eye or the environment and were not consistent within or

between protocols. Two of thirty nine dogs (5%) available for follow up had transient mild epiphora;

neither dog had a goniolens that had cultured positive placed on their eyes. In the group with

cleaned lenses there was a single positive culture (4.8%). There was no significant difference

between the contamination rate of the pooled “unwashed” lenses (11.7%) and the “washed” lenses

(4.8%).

Conclusions - The rate of bacterial contamination of goniolenses in clinical practice in this study is

low and the bacterial contaminants consist of commensal bacterial, unlikely to be of detriment to

an eye with an intact epithelium. Extensive cleaning protocols of the lenses between dogs are not

required however cleanliness could be improved. Although the washing protocol did not

significantly reduce contamination with these sample numbers cleaning lenses should be

encouraged between corneal contacts.

Support - The generous support of BrAVO Research Grant is acknowledged.

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ncer

ned

mai

nly

with

the

seco

ndar

y vi

treou

s ex

cept

in c

erta

in

rela

tivel

y ra

re s

ituat

ions

suc

h as

per

sist

ent

prim

ary

hype

r pla

stic

vitr

eous

(PH

PV) o

r len

s zo

nule

loss

and

lens

inst

abilit

y.

•Th

e vi

treou

s is

mai

nly

wat

er w

ith a

sm

all a

mou

nt

of c

olla

gen

and

hyal

uron

ic a

cid

to g

ive

it st

ruct

ure

•Al

mos

t all

visi

ble

light

is tr

ansm

itted

thro

ugh

the

vitre

ous.

•Th

e vi

treou

s fo

rms

a fir

m a

ttach

men

t to

the

retin

a in

onl

y 2

plac

es.

The

ora

cilia

ris re

tinae

(p

erip

hera

l ext

ent o

f the

retin

a ne

ar th

e le

ns) a

nd

the

edge

of t

he o

ptic

ner

ve.

Thes

e ar

e tw

o “h

ot

spot

s” in

the

path

ogen

esis

of r

etin

al d

etac

hmen

t (R

D)

•Th

e ou

ter e

xten

t of t

he p

oste

rior v

itreo

us c

orte

x fo

rms

a ra

ther

loos

e at

tach

men

t with

the

base

men

t mem

bran

e of

the

Mul

ler c

ells

. Th

is

base

men

t mem

bran

e is

kno

wn

as th

e IL

M, w

hich

is

ver

y im

porta

nt in

the

path

ogen

esis

of r

etin

al

deta

chm

ents

in h

uman

s.

•Th

e w

eak

atta

chm

ent o

f the

pos

terio

r hya

loid

m

embr

ane

and

the

ILM

is a

noth

er “h

otsp

ot”.

•In

mos

t dom

estic

ani

mal

s re

tinal

thic

knes

s is

ab

out 2

00um

at t

he o

ptic

ner

ve a

nd a

bout

10

0um

at t

he o

ra c

iliaris

retin

ae.

•Th

us in

man

y in

stan

ces,

tear

s oc

cur i

n th

e w

eake

r thi

nner

per

iphe

ry o

f the

retin

a.

•An

d in

deed

, as

a re

tina

surg

eon,

the

maj

ority

of

case

s th

at w

e se

e ar

e 36

0 de

gree

tear

s ne

ar th

e or

a ci

liaris

retin

ae.

•O

ne o

f the

stro

nges

t vitr

eal a

ttach

men

ts is

the

vitre

ous

base

nea

r the

ora

cilia

ris re

tinae

and

th

is c

ombi

ned

with

a th

inne

r wea

ker r

etin

a in

this

ar

ea, m

ake

this

a b

ig h

otsp

ot fo

r ret

inal

tear

s

•In

the

cani

ne e

ye, m

uch

path

olog

y oc

curs

nea

r th

e vi

treou

s ba

se th

at c

an le

ad to

RD

. W

e w

ill ta

lk a

bout

this

are

a m

ore

in th

e re

tinal

dis

ease

s se

ctio

n.

•So

, in

sum

mar

y

•Th

e re

tina

adhe

res

to th

e RP

E th

roug

h a

varie

ty

of c

ompl

ex c

ompl

imen

tary

mec

hani

sms.

•Th

ese

mec

hani

sms

incl

ude;

•Pr

essu

re o

n th

e re

tina

from

the

vitre

ous,

the

IPM

w

hich

act

s lik

e gl

ue, i

nter

digi

tatio

n w

ith th

e RP

E m

icro

villi,

and

the

ioni

c pu

mp

of th

e RP

E w

hich

de

hydr

ates

the

sub

retin

al s

pace

.

•Es

sent

ially

phy

sica

l AN

D m

etab

olic

pro

cess

es

play

a ro

le

•Th

us th

e m

anag

emen

t of R

D s

houl

d in

clud

e at

tent

ion

to b

oth

the

phys

ical

, as

wel

l as

the

met

abol

ic p

rope

rties

of r

etin

al a

ttach

men

t

Pseu

doph

akic

retin

al

deta

chm

ent

Joe

Wol

fer

Toro

nto

Can

ada

Ridi

culo

usly

goo

d lo

okin

g

•If

anyo

ne is

inte

rest

ed in

con

tact

ing

me

with

qu

estio

ns, m

y ad

dres

s is

•jw

olfe

r@sy

mpa

tico.

ca

•Th

e ex

act i

ncid

ence

of R

D a

fter c

atar

act s

urge

ry

in th

e do

g is

unk

now

n an

d th

ere

real

ly h

ave

been

no

thor

ough

stu

dies

don

e to

det

erm

ine

this

•H

owev

er, m

y be

lief i

s th

at 2

-4%

of c

atar

act

patie

nts

will

deve

lop

RD p

ost-o

pera

tivel

y

•Et

iopa

thog

enes

is o

f pse

udop

haki

c RD

is

unkn

own,

how

ever

, pos

sibl

e pr

oble

ms

incl

ude:

•D

isru

ptio

n of

the

post

erio

r len

s ca

psul

e. T

ears

in

the

post

erio

r len

s ca

psul

e in

crea

se th

e ris

k of

RD

and

mak

e re

tinal

sur

gery

mor

e di

fficu

lt, a

s si

licon

e oi

l will

mig

rate

thro

ugh

the

PC te

ar a

nd

into

the

ante

rior s

egm

ent

•Te

ars

in th

e PC

allo

w fl

uid

from

the

ante

rior

segm

ent i

nto

the

post

erio

r seg

men

t, de

stab

ilizin

g th

e vi

treor

etin

al in

terfa

ce

•C

atar

act s

urge

ry c

ause

s m

inor

trau

ma

to th

e le

ns a

nd m

ay a

pply

forc

es to

the

lens

zon

ules

. Th

is c

ould

pos

sibl

y ap

ply

forc

es to

the

atta

chm

ent o

f the

retin

a at

the

ora

cilia

ris re

tinae

, an

d/or

exa

cerb

ate

cyst

oid

retin

al d

egen

erat

ion

in th

is a

rea,

cre

atin

g a

retin

al te

ar.

•Po

st-o

pera

tive

IOP

spik

es, m

ay s

tretc

h th

e gl

obe

appl

ying

tens

ion

to th

e re

tina

and

caus

ing

tear

s

•Pr

e-op

erat

ive

lens

indu

ced

uvei

tis h

as b

een

asso

ciat

ed w

ith a

n in

crea

sed

inci

denc

e of

RD

. C

hang

es in

the

vitre

ous

due

to in

flam

mat

ion

of

the

cilia

ry b

ody

may

resu

lt in

RD

•H

yper

mat

ure

cata

ract

s. A

s th

e ca

tara

ct

prog

ress

es fr

om m

atur

e to

hyp

er m

atur

e, le

ns

prot

eins

leak

from

the

lens

, cau

sing

lens

in

duce

d uv

eitis

whi

ch w

e kn

ow in

crea

ses

the

risk

of R

D

•Al

so, a

s th

e le

ns s

hrin

ks a

nd th

e ca

psul

e be

com

es w

rinkl

ed te

nsio

n m

ay b

e br

ough

t to

bear

on

the

lens

zon

ules

incr

easi

ng th

e ris

k fo

r RD

•Al

so, a

s th

e ca

tara

ct re

ache

s th

is s

tage

, len

s ep

ithel

ium

mig

rate

s on

to th

e po

ster

ior c

apsu

le

and

may

nec

essi

tate

pos

terio

r cap

sule

ctom

y to

gi

ve a

cle

ar v

isua

l axi

s.

•Po

ster

ior c

apsu

lect

omy

incr

ease

s th

e ris

k fo

r RD

•D

iabe

tic c

atar

acts

; m

any

diab

etic

cat

arac

ts

beco

me

intu

mes

cent

(sw

olle

n) s

tretc

hing

the

zonu

les

and

alte

ring

the

vitre

ous

base

. Th

is m

ay

lead

to R

D

•If

the

lens

bec

omes

too

swol

len,

the

post

erio

r le

ns c

apsu

le m

ay ru

ptur

e ex

trudi

ng p

art o

f the

le

ns in

to th

e vi

treou

s an

d in

crea

sing

the

risk

for

RD

•Le

ns lu

xatio

n; i

f the

lens

mus

t be

rem

oved

by

an in

traca

psul

ar te

chni

que

due

to lu

xatio

n,

inci

denc

e of

RD

is h

ighe

r.

•Le

ns lu

xatio

n di

srup

ts th

e an

terio

r hya

loid

face

pr

edis

posi

ng to

RD

•So

me

surg

eons

rout

inel

y pe

rform

TPL

R af

ter

lens

luxa

tion

surg

ery.

•Th

e m

ost i

mpo

rtant

spe

cific

pro

blem

to

pseu

doph

akic

RD

is d

isru

ptio

n of

the

bloo

d oc

ular

bar

rier b

y pr

ior c

atar

act s

urge

ry

•It

take

s m

onth

s fo

r the

BO

B to

refo

rm c

ompl

etel

y af

ter c

atar

act s

urge

ry, a

nd s

urge

ry o

n ps

eudo

phak

ic p

atie

nts

is u

sual

ly p

erfo

rmed

w

ithin

wee

ks a

fter t

he in

itial

cat

arac

t sur

gery

•Th

e BO

B is

ther

efor

e w

eak

and

the

eye

is m

ore

infla

mm

ed.

This

lead

s to

a s

ofte

r eye

and

po

ssib

le o

paci

ficat

ion

of th

e oc

ular

med

ia.

This

m

akes

vis

ualiz

atio

n of

the

retin

a m

ore

diffi

cult

•An

terio

r an

d po

ster

ior s

egm

ent b

leed

ing

is

mor

e co

mm

on

•Th

ere

is o

ften

an IO

L pr

esen

t and

this

mak

es

visu

aliz

atio

n of

the

retin

a m

ore

diffi

cult

as w

ell.

•To

cou

nter

act t

hese

fact

ors,

it is

impo

rtant

to

plac

e pa

tient

s on

ora

l cor

ticos

tero

ids

prio

r to

surg

ery

•If

poss

ible

, tw

o da

ys p

rior t

o re

tinal

sur

gery

, the

vi

treou

s is

inje

cted

with

1.2

5mg

of A

vast

in

(bev

aciz

umab

), an

ant

i-vas

cula

r end

othe

lial

grow

th fa

ctor

(veg

f) ag

ent.

•Th

is w

ill st

abiliz

e th

e BO

B an

d fa

cilit

ate

an

easi

er s

urge

ry

•W

ith y

our p

ost-c

atar

act s

urge

ry p

atie

nts

you

neve

r kno

w w

hat y

ou w

ill ge

t bre

ed-w

ise.

•M

any

are

not b

rach

ycep

halic

and

it m

ay b

e di

fficu

lt to

pro

ptos

e th

e ey

e.

•Th

is m

akes

it d

ifficu

lt to

get

ade

quat

e ex

posu

re

to th

e pa

rs p

lana

are

a

•H

owev

er, w

ith th

e ne

w 2

3g tr

ocar

tech

nolo

gy it

is

muc

h ea

sier

to d

o su

rger

y on

eye

s th

at h

ave

not

been

pro

ptos

ed

A novel ADAMTS17 mutation is associated with primary open angle glaucoma and primary lens luxation in the Shar Pei

James A. C. Oliver1, Sophie Rustidge1, Louise Pettitt1, Christopher A. Jenkins1, Fabiana H. G. Farias2, Elizabeth A. Giuliano3, Cathryn S. Mellersh1

1The Canine Genetics Research Department of The Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk, CB8 7UU, United Kingdom

2The Department of Pathobiology, The College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, U.S.A.

3The Department of Veterinary Medicine and Surgery, The College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, U.S.A.

Abstract

Introduction. Mutations in ADAMTS17 (CFA3) are associated with both primary open angle glaucoma (POAG) and primary lens luxation (PLL) in several dog breeds. We investigated ADAMTS17 as a candidate gene for these conditions in the Shar Pei – a breed in which both POAG and PLL have been reported.

Materials & Methods. DNA was obtained from Shar Pei classified as either affected or unaffected for POAG and/or PLL. We initially performed ADAMTS17 exon resequencing in 10 Shar Pei with POAG and/or PLL. We identified a provocative candidate mutation, which was then genotyped in additional affected and unaffected Shar Pei and in dogs of other breeds to confirm association with disease. RNA was extracted from ocular tissues of one affected and one unaffected dog and reverse transcribed to cDNA. Sanger sequencing of the cDNA was undertaken, as well as expression analysis of ADAMTS17 using qRT-PCR.

Results. All affected Shar Pei were homozygous for a 6 bp deletion in exon 22 of ADAMTS17. Forty-two clinically unaffected Shar Pei were all either heterozygous or homozygous for the wild type allele. The association of the deletion with POAG/PLL was statistically significant (p = 3.79 x10-14), and this variant was not identified in 95 dogs of other breeds. Sanger sequencing of cDNA confirmed the presence of the mutant transcript in the affected eye and the normal transcript in the unaffected eye. Quantitative RT-PCR revealed a 4-fold reduction in the expression of ADAMTS17 transcript in affected ocular tissue (p = 0.0006).

Conclusions. POAG and PLL are both associated with the same novel mutation in ADAMTS17 in the Shar Pei providing evidence that the diseases are genetically indistinguishable. This finding has led to the development of a DNA test which will allow the diseases to be eradicated from the breed.

BrAVO travel scholarship report 2017 Introduction Orangutans (Pongo pygmaeus and Pongo abeii) are the only great apes of Asia (Borneo and Sumatra respectively), and have been recently reclassified as critically endangered on the IUCN red list. Wild orangutan populations are threatened by poaching (especially in animal-human conflicts e.g. palm oil plantations), habitat loss or degradation, and the illegal pet trade. Several conservation and rehabilitation organisations are dedicated to the survival of orangutans in the wild. During the period 1973–2010, 39% of Bornean forests were lost (Gaveau et al. 2014), representing a net loss of 98,730 km² of prime orangutan habitat. It is estimated that a further 37% of suitable orangutan habitat (155,106 km²) will be converted to plantations between 2010 and 2025, which accounts for the loss of an additional 57,140 km² of orangutan habitat (Wich et al. 2012). Using a questionnaire survey it was estimated that 630–1357 Bornean Orangutans were killed in 2008 and that an average of 2383–3882 per year had been killed during the lifetimes of the survey respondents (Meijaard et al. 2011). The mean estimate (2256 orangutans poached in Kalimantan each year) equates to 2.6% of the 2010 population for Kalimantan. The combined impacts of habitat loss, habitat degradation and illegal hunting equate to an 86% population reduction between 1973 and 2025 which qualifies the species for listing as Critically Endangered. This estimate is relatively conservative, as it does not include additional future population losses anticipated due to stochastic effects that will reduce populations inhabiting increasingly small forest fragments. Orangutans are arboreal and make nests (from branches and foliage) each evening to sleep in. Orangutans are generally solitary, with social bonds occurring primarily between mothers and their dependent and weaned offspring. Infants remain completely dependent on their mother until 2 years of age, and are weaned at approximately 4 years old. Juveniles learn ‘forest skills’ from their mothers who generally have a period of 8 years between offspring. Males are generally larger, and dominant adult males (post-pubescence, approx. 15 years old) have distinctive cheek pads (‘flanges’) and produce long calls that attract females and intimidate rivals. Younger males resemble adult females. Adult males in the presence of a dominant male remain unflanged, but can reproduce if the opportunity arises (he can mate with a female in oestrus without getting caught by the dominant male). Fruit is the most important component of an orangutan's diet (65-90%), although they will also eat vegetation. Life expectancy in the wild is approx. 25years (Wich et al 2009). ‘Aan’, an estimated 20 year old female Orangutan was rescued in 2012 following air-rifle injuries on a palm oil plantation (human-animal conflict). Multiple superficial pellets were removed but deeper pellets could not be retrieved. (see Fig 1.) Due to behaviour suggestive of blindness, ‘Aan’ was kept in a forest cage (solitary) for her own safety.

Fig 1. Radiograph of Aan at time of rescue

The ophthalmic examination In September 2016, and under anaesthesia Aan was examined at Camp Gemini, Pangkalan Bun, Indonesia. Examination of the right eye revealed a Schirmer tear test reading of

0mm/min (likely secondary to the xylazine). The cornea was clear and revealed a mature cataract with iridal trauma at approximately 5 o’clock on the iris margin. There was a strand of fibrotic tissue and exposure of a triangle of posterior pigmented iris epithelium. There were multifocal spots of pigment on her anterior lens capsule (likely dispersed from the iris on trauma). The pupil was responsive to light; tropicamide was applied to dilate the pupil. Direct examination of the posterior segment was not possible due to the presence of the cataract (obscuring visualisation). Her intraocular pressure was 20mmHg in this eye. There was no discernible aqueous flare. Ocular ultrasound confirmed the presence of a cataract with some vitreal degeneration and mobile membranes. There was a hyperechoic line close to the optic nerve head in the medial retina that could represent a partial retinal detachment. It is possible it represented posterior vitreal detachment, although it remained partially visible even on reduction of the gain. Orbital ultrasound was also performed which revealed some images of an apparently intact optic nerve. There was a cross-shaped hyperechoicity adjacent to the optic nerve but this was not accompanied by an acoustic shadow (as might be expected for an air rifle pellet). Ocular electroretinography was also performed after (partial, approx. 75%) dilation of the pupil (tropicamide). This revealed a repeatable positive trace. Optic nerve disruption more posteriorly could not be excluded (no access to MRI for example), although the presence of a pupillary light reflex was considered a positive indicator.

Fig. 2 a. Right eye b. Left eye c. ultrasound of right eye b. Left eye

BrAVO sponsored surgical expedition The expedition planned to undertake phacoemulsification of the cataract in Aan’s right eye and enucleation of her left (phthisical) eye. The aim was to restore uniocular vision in this animal, to permit release and potential breeding from this conservationally valuable individual.

Surgery was performed under general anaesthesia (medetomidine, tiletamine and zolazepam, with gaseous isofluorane & O2) performed by Dr John Lewis MA, VetMB, PhD, MRCVS, RCVS Specialist in Zoo and Wildlife Medicine. Stay sutures were placed as neuromuscular blockade was not attempted. Phacoemulsification was straightforward although no artificial intraocular lens was placed due to a radial capsular tear. The left eye was removed by a transconjunctival approach. Recovery from anaesthesia was extended, requiring veterinary supervision overnight at the island camp.

Topical medications were not possible. A subconjunctival injection of aqueous dexamethasone and chloramphenicol ointment were administered at the completion of surgery. Oral paediatric ibuprofen suspension and amoxycillin tablets were given orally disguised in fruit.

Although her right eye was exceptionally clear post-operatively, Aan did not regain vision, and optic nerve/chiasm trauma was assumed. Lifelong solitary captivity was now the only option and environmental enrichment was prioritised.

VitreoretinalSurgery

Malcolm Woodcock Worcestershire Acute NHS Trust &

Birmingham and Midland Eye Centre

VITREORETINAL SURGERY

▪ Macular holes ▪ Epiretinal membranes ▪ Retinal detachments ▪ Severe diabetic retinopathy ▪ Complications from cataract surgery ▪ Complications or Age-related Macular

Degeneration (AMD) ▪ Ocular trauma

VITRECTOMY - HISTORY

▪ Machemer 1970 reported the successful removal of longstanding vitreous haemorrhages in a group of diabetic patients

▪ Over the next four decades refinements in surgical techniques have expanded the indications and capability of vitreous surgery

▪ Some of the advances are the use of long-term vitreous replacements, endolaser photocoagulation, panoramic viewing systems, and perfluorocarbon liquids.

VITRECTOMY

▪ This is done through three small (20G, 23G or 25G) pars plana incisions entering the vitreous space. An infusion line is placed to restore fluid which is aspirated by a vitreous cutter

VISUALISATION

▪ Wide field or panoramic viewing system

▪ Optical principles of indirect ophthalmoscopy creating a virtual image with high plus condensing lenses.

▪ Large field of view up to 130º.

▪ Inverted image. The image is reverted by a prism system mounted on the surgical microscope.

Epiretinal Membrane

▪ Sheet of fibroblast-like cells

▪ Scrunches macula beneath

▪ Distortion and reduced vision

▪ Vitrectomy/ERM peel

Epiretinal Membrane Peel

Macular Hole

▪ Hole at fovea (≤ 400µm) ▪ Drops VA to 6/60 +

distortion ▪ F>M, 15% risk to fellow

eye ▪ Vitrectomy, peel of

retinal inner limiting membrane + gas tamponade

Peeling the Inner Limiting Membrane of the Retina

Posterior Vitreous Detachment and Retinal Detachment

▪ Vitreous is a polymer of water which breaks down with age

▪ New cobweb-like floater (Red flag - flashes, multiple small floaters, shadows, loss of vision)

▪ Past ocular surgery – previous cataract surgery

Retinopexy

cryotherapy

laser

Retinopexy-laser

Retinal Detachment

Surgical treatment - Objectives

1. mechanically appose the sensory retina and retinal pigment layer (closing the break)

2. to prevent the retinal tear from reopening

RD-Surgical manoeuvres

1. Retinal coagulation (cryotherapy and laser)

1. Scleral buckling (indentation of the eye wall) +/- additional procedures

2. Vitrectomy and internal tamponade

Risks of Surgery

▪ < 1 in 800 chance of blindness due to surgery ▪ 20% chance of requiring more than one

procedure ▪ Overall 97% success rate ▪ Cataract ▪ Glaucoma

INTRAOCULAR GASES

1. Usually either perfluropropane (C3F8) or sulphur hexafluoride (SF6)

2. When mixed with sterile air have the property of remaining in the eye for extended periods of time (up to two months)

3. Possible complications of intraocular gas include progression of cataracts and elevated eye pressure (glaucoma)

4. It is unsafe to fly in a plane while gas remains in the eye.

5. Nitrous Oxide?

Cyro/buckle procedure

Scleral buckling appliances

Encircling silicone band

Solid silicone tyre

Silicone sponge

Severe diabetic retinopathy

▪ Extensive fibrovascular membrane

▪ Lead to tractional retinal detachment

▪ Chronic macular oedema

Complications of cataract surgery

▪ “dropped nucleus” ▪ If anterior lens

capsulae intact – sulcus fixated IOL

▪ If no capsular support then other lens options available.

Suprachoroidal and Subretinal Haemorrhages

❖Often secondary to age related macular degeneration

❖Rapid loss, & sometimes devastating, loss of vision

❖Clearing blood from beneath the macula is vital if any vision is to be salvaged

TRAUMA

Machete or “Panga”

Scleral lacerations

These are not always obvious. Look for:

▪ Slightly oval pupil ▪ Anterior chamber deeper

than other eye ▪ Hyphaema in the

presence of a lid laceration

Total hyphaema with edge of scleral laceration visible on downgaze

Military Setting

Conflict Eye Injuries % US Civil War 0.52

WW1 1.54 WW2 2-3 Korea 2-8

Arab-Israeli 5-10 Vietnam 5-9

Gulf 13

Source Metal Composition Shells (Naval 5” and 155mm Artillery)

High grade steel (98% Fe, 1.7% Cu, 0.2% Mn) with 99.5% Cu rotation band

Bombs (2000, 1000 and 500 lbs)

Grade 302/303 stainless steel (69% Fe, 18% Cr, 9% Ni & Mn) and lead based paint.

Cluster Bomb Units Grade 301 steel (69% Fe, 19% Ni, 0.15% Cr), pyrotechnic Sirconium and plastic fins

Land Mines Aluminium alloy Grenades Zn alloy base, Grade 302 steel lever, Barium chromate

parts & zirconium-nickel alloy parts Bullets (Rifle) Brass or Cu jacket, lead-tin alloy and steel core (brass

jackets usually have pure copper rotating bands) Bullets (small calibre) Lead and lead-tin alloy BBs Various (Brass, Cu alloy, steel) Pellet-gun pellets Lead-tin alloy

Thank You

Retin

al d

etac

hmen

t; ca

use

and

type

Joe

Wol

fer

Toro

nto

Can

ada

•Re

tinal

det

achm

ent i

s th

e se

para

tion

of th

e ne

uros

enso

ry re

tina

from

the

unde

rlyin

g re

tinal

pi

gmen

t epi

thel

ium

(RPE

)

•A

retin

al d

etac

hmen

t can

be

eith

er

rheg

mat

ogen

ous

(RRD

) or n

on-rh

egm

atog

enou

s (n

on-R

RD)

•Rh

egm

atog

enou

s m

eans

that

ther

e ha

s be

en a

n ac

tual

tear

in th

e re

tina

itsel

f.

•In

a R

RD, fl

uid

from

the

vitre

ous

cavi

ty e

nter

s th

e su

b re

tinal

spa

ce th

roug

h a

brea

k in

the

retin

a.

•RR

D c

an b

e ei

ther

prim

ary

or s

econ

dary

•Pr

imar

y RR

D a

re s

pont

aneo

us a

nd a

re n

ot th

e re

sult

of tr

aum

a, in

flam

mat

ion,

sur

gery

or a

ny

othe

r spe

cific

ocu

lar d

isor

der

•Pr

imar

y RR

D is

pre

cede

d by

alte

ratio

ns in

the

vitre

ous

whi

ch p

redi

spos

e to

retin

al d

etac

hmen

t

•Th

e m

ost c

omm

on R

RD is

retin

al d

ialy

sis

or

gian

t ret

inal

tear

see

n in

the

Shih

Tzu

•In

this

bre

ed th

e re

tinal

tear

is th

ough

t to

occu

r af

ter v

igor

ous

head

sha

king

•Th

e vi

goro

us h

ead

shak

ing

cau

ses

a co

up-

cont

rcou

p ef

fect

dam

agin

g th

e re

tina.

Bec

ause

th

ese

Shih

Tzu

’s ha

ve a

liqu

ified

vitr

eous

, the

re is

no

thin

g to

hol

d th

e re

tina

in p

lace

dur

ing

this

vi

goro

us s

haki

ng.

•It

is a

lso

my

opin

ion,

that

man

y of

thes

e do

gs

have

per

iphe

ral c

ystic

cha

nge

in th

e re

tina

that

re

sults

in a

wea

k sp

ot th

at te

ars

mor

e ea

sily

du

ring

head

sha

king

.

Can

ine

•I b

elie

ve th

at p

rem

atur

e vi

treal

liqu

efac

tion

occu

rs in

the

Shih

Tzu

, and

man

y ot

her b

reed

s,

as a

prim

ary

inhe

rited

dis

orde

r.

•W

hen

a re

tinal

dia

lysi

s oc

curs

, the

neu

rose

nsor

y re

tina

tear

s aw

ay a

t the

ora

cilia

ris re

tinae

.

•A

gian

t ret

inal

tear

(GRT

) inv

olve

s 90

deg

rees

or

mor

e of

retin

al c

ircum

fere

nce

with

atta

ched

vi

treou

s ge

l to

an a

nter

ior fl

ap o

f ret

ina

•Th

ese

tear

s us

ually

, and

fairl

y ra

pidl

y, pr

ogre

ss

from

a d

orsa

l RD

to a

com

plet

e de

tach

men

t

•Th

is re

sults

in a

retin

a th

at h

angs

lim

ply

from

the

optic

ner

ve h

ead

in a

vei

l-lik

e co

nfigu

ratio

n.

•Th

is re

tina

may

als

o be

twis

ted

arou

nd it

self,

up

to 9

0 de

gree

s

•An

othe

r for

m o

f prim

ary

RRD

invo

lves

opt

ic

nerv

e co

lobo

ma,

suc

h as

in s

een

in C

ollie

eye

an

omal

y (C

EA)

•In

this

dis

orde

r the

re is

sep

arat

ion

of re

tinal

la

yers

at t

he ju

nctio

n of

the

colo

bom

a an

d no

rmal

retin

al ti

ssue

•Th

is a

llow

s flu

id fr

om th

e re

tina

to e

nter

the

sub

retin

al s

pace

•O

ther

type

s of

prim

ary

retin

al d

etac

hmen

ts

invo

lve

atro

phic

retin

al te

ars

or h

oles

•Th

ese

atro

phic

hol

es c

an o

ccur

sec

onda

ry to

ag

e or

occ

ur in

are

as o

f pre

viou

s re

tinal

in

flam

mat

ion

•Se

cond

ary

RRD

is c

ause

d by

trau

ma,

gla

ucom

a (s

tretc

hing

of t

he g

lobe

), le

ns s

urge

ry (e

ither

le

nsec

tom

y fo

r len

s lu

xatio

n, o

r ph

acoe

mul

sific

atio

n), a

ggre

ssiv

e la

ser

retin

opex

y, or

sur

gery

invo

lvin

g th

e ci

liary

bod

y

•Th

e m

ost p

rom

inen

t cau

se o

f sec

onda

ry R

RD is

ca

tara

ct s

urge

ry.

•N

on-R

RD is

cla

ssifi

ed a

s ei

ther

ser

ous

(flui

d bu

ild u

p un

der t

he re

tina)

or t

ract

iona

l

•Se

rous

retin

al d

etac

hmen

t occ

urs

with

out a

br

eak

in th

e re

tina

and

resu

lts fr

om fl

uid

accu

mul

atio

n be

twee

n th

e ph

otor

ecep

tors

and

th

e RP

E. S

erou

s RD

can

be

eith

er in

flam

mat

ory

or e

xuda

tive.

•Th

e m

ost c

omm

on c

ause

s ar

e im

mun

e m

edia

ted

chor

oidi

tis, i

nfec

tious

cho

roid

itis,

neo

plas

ia, o

r hy

perte

nsio

n.

•Tr

actio

nal R

D o

ccur

s w

hen

ther

e is

a p

ullin

g fo

rce

(ban

d or

mem

bran

e) in

the

vitre

ous

that

fo

rces

the

retin

a to

sep

arat

e fro

m th

e RP

E

•Th

is c

an re

sult

from

pen

etra

ting

inju

ry to

the

post

erio

r seg

men

t, pr

evio

us in

flam

mat

ion,

pr

evio

us v

itrea

l hem

orrh

age

or a

s a

prim

ary

vitre

al d

yspl

asia

in s

ome

bree

ds

•Tr

actio

nal R

D is

ver

y di

fficu

lt to

trea

t in

the

dog

•Re

quire

s m

etic

ulou

s vi

trect

omy

and

mem

bran

e pe

elin

g w

hich

is v

ery

diffi

cult

in th

e do

g

•M

embr

anes

ofte

n re

grow

afte

r sur

gery

mak

ing

RD re

curre

nces

hig

h

•In

hum

ans

the

mos

t com

mon

cau

se o

f tra

ctio

nal

RD is

dia

betic

retin

opat

hy

•En

doph

thal

miti

s or

infla

mm

atio

n of

the

entir

ety

of

the

glob

e is

ano

ther

cau

se o

f RD

•It

is a

n in

flam

mat

ory

resp

onse

to in

fect

ion,

ba

cter

ial,

fung

al, p

aras

itic

or v

iral

•In

dog

s, th

e m

ost c

omm

on c

ause

for

endo

phth

alm

itis

is c

atar

act s

urge

ry

•Al

l pos

t-ope

rativ

e en

doph

thal

miti

s ca

ses

shou

ld

unde

rgo

ocul

ar u

ltras

ound

•Be

st th

erap

y fo

r end

opht

halm

itis

is in

travi

treal

an

tibio

tics

and

ster

oids

(Trie

ssen

ce)

•C

ompl

ete

vitre

ctom

y m

ay b

e re

quire

d bu

t is

diffi

cult

due

to th

e br

eakd

own

in th

e bl

ood

ocul

ar

barri

er

•In

travi

treal

van

com

ycin

and

Trie

ssen

ce is

my

mai

nsta

y th

erap

y

•Le

ns lu

xatio

n ca

n be

ano

ther

pre

curs

or to

RD

du

e to

dis

rupt

ion

of le

ns z

ones

at t

he o

ra e

rrata

.

•Th

ere

is a

lso

disr

uptio

n of

the

ante

rior h

yalo

id

face

cau

sing

liqu

efac

tion

of th

e vi

treou

s.

•Ad

junc

tive

trans

pupi

llary

lase

r ret

inop

exy

may

de

crea

se th

e ra

te o

f RD

afte

r sur

gery

for l

uxat

ed

lens

.

•D

ropp

ed n

ucle

ar fr

agm

ents

dur

ing

phac

oem

ulsi

ficat

ion

•In

hum

ans,

PPV

and

frag

men

t rem

oval

is

perfo

rmed

if >

25%

of t

he n

ucle

us is

pre

sent

•In

dog

s, P

PV d

urin

g th

e co

urse

of a

cat

arac

t su

rger

y is

ext

rem

ely

diffi

cult

to d

o. T

he c

orne

al

inci

sion

mus

t be

clos

ed a

nd th

e ey

e pr

opto

sed

for p

rope

r exp

osur

e.

•20

g PP

V is

then

per

form

ed a

n a

fragm

atom

e is

in

trodu

ced

to e

mul

sify

the

nucl

ear f

ragm

ents

•In

my

opin

ion,

it is

act

ually

eas

ier,

and

safe

r to

perfo

rm a

nter

ior v

itrec

tom

y th

roug

h th

e co

rnea

l in

cisi

on, a

nd th

en u

se th

e ph

acop

robe

to

capt

ure

and

emul

sify

the

nucl

ear f

ragm

ents

. So

me

fragm

ents

may

be

left

behi

nd if

they

are

sm

all.

•Sy

stem

ic s

tero

ids

are

requ

ired

post

-ope

rativ

ely

Tran

pupi

llary

lase

r re

tinop

exy;

whe

n is

this

us

eful

Joe

Wol

fer

Toro

nto

Can

ada

•Tr

ying

to d

ecid

e if

you

shou

ld d

o fu

ll pa

rs p

lana

re

tinal

sur

gery

, or s

impl

y do

tran

spup

illary

lase

r re

tinop

exy

can

be c

onfu

sing

.

•Tr

ansp

upilla

ry la

ser r

etin

opex

y, or

TPL

R, is

onl

y us

eful

if th

ere

is s

ome

retin

a st

ill at

tach

ed.

•La

ser b

urns

into

the

chor

oid,

can

onl

y be

mad

e if

the

retin

a is

in d

irect

app

ositi

on to

the

RPE

•Th

e m

ost c

omm

on ti

me

for T

PLR

to b

e us

ed is

in

a re

tinal

det

achm

ent i

mm

edia

tely

afte

r cat

arac

t su

rger

y. S

ince

thes

e do

gs a

re b

eing

mon

itore

d ca

refu

lly, t

he d

etac

hmen

t is

usua

lly s

een

at a

n ea

rly s

tage

•Th

e ot

her c

omm

on ti

me

for T

PLR

to b

e us

ed is

w

hen

a la

tera

l or v

entra

l det

achm

ent i

s se

en o

n ul

traso

und

and

the

owne

rs c

anno

t affo

rd

com

bine

d ph

aco/

pars

pla

ns v

itrec

tom

y

•In

that

cas

e, I

will

perfo

rm ro

utin

e ph

acoe

mul

sific

atio

n w

ith n

o IO

L. A

nd th

en

perfo

rm p

erfo

rm a

tran

spup

illary

lase

r re

tinop

exy

(bar

rier r

etin

opex

y)

•O

nce

the

retin

a is

com

plet

ely

deta

ched

, we

are

beyo

nd th

e po

int o

f doi

ng T

PLR.

•TP

LR is

use

d in

circ

umst

ance

s w

here

ther

e is

a

parti

al re

tinal

det

achm

ent,

but p

ars

plan

a vi

trect

omy

is u

ndes

irabl

e.

•So

me

owne

rs c

anno

t affo

rd fu

ll re

tinal

sur

gery

or

the

eye

may

be

too

fragi

le to

with

stan

d pa

rs

plan

a vi

trect

omy

•Ba

rrier

retin

opex

y w

orks

bes

t if t

he te

ar in

the

retin

a is

late

ral t

o th

e op

tic n

erve

hea

d an

d no

t su

perio

r.

•Su

perio

r tea

rs te

nd to

pro

gres

s ra

pidl

y an

d br

eak

thro

ugh

the

lase

r ret

inop

exie

s du

e to

gr

avity

and

the

wei

ght o

f the

retin

a.

•TP

LR is

per

form

ed w

ith a

lase

r ind

irect

hea

dset

an

d a

diod

e la

ser a

ttach

men

t. A

20g

lens

is

used

to fo

cus

the

lase

r bea

m to

a p

inpo

int o

n th

e re

tinal

sur

face

•Pa

tient

is in

dor

sal o

r ste

rnal

recu

mbe

ncy

depe

ndin

g on

the

natu

re a

nd p

ositi

on o

f the

de

tach

men

t

•Th

e pu

pil i

s di

late

d m

axim

ally

prio

r to

indu

ctio

n of

ane

sthe

sia.

Int

rave

nous

neu

ropa

raly

tic is

re

quire

d to

mov

e th

e ey

e ce

ntra

lly.

•Li

d sp

ecul

um a

nd s

tay

sutu

res

may

als

o be

re

quire

d

•La

ser b

urns

are

then

pla

ced

in a

dou

ble

or tr

iple

ro

w a

long

the

lead

ing

edge

of t

he d

etac

hmen

t to

prev

ent p

rogr

essi

on o

f the

det

achm

ent

•La

ser s

ettin

gs v

ary

depe

ndin

g up

on d

egre

e of

pi

gmen

tatio

n, a

ngle

of i

ncid

ence

of t

he la

ser

beam

, and

rela

tive

opac

ifica

tion

of th

e oc

ular

m

edia

•I g

ener

ally

sta

rt at

abo

ut 2

00m

W a

nd 5

00m

s.

•G

radu

ally

wor

k up

war

ds in

pow

er u

ntil

whi

te

spot

s ap

pear

in th

e re

tina

so th

at y

ou k

now

that

a

burn

has

bee

n cr

eate

d.

•It

take

s ap

prox

imat

ely

14 d

ays

for t

he la

ser

burn

s to

reac

h th

eir m

axim

um s

treng

th, s

o th

e pa

tient

mus

t be

kept

ent

irely

qui

et fo

r tha

t du

ratio

n.

•C

age

rest

is id

eal

•TP

LR w

orks

bes

t on

phak

ic p

atie

nts.

Aph

akic

ey

es d

o no

t foc

us th

e la

ser b

eam

as

wel

l.

•Ps

eudo

phak

ic e

yes

are

mor

e di

fficu

lt as

you

m

ust s

omet

imes

wor

k ar

ound

the

IOL

to g

et th

e la

ser b

urns

in th

e rig

ht p

lace

•Th

e ot

her t

echn

ique

for b

arrie

r ret

inop

exy

is

perfo

rmed

via

use

of a

n en

dola

ser.

•Th

is p

roce

dure

invo

lves

rem

oval

of t

he c

atar

acts

le

ns, f

ollo

wed

by

mak

ing

a sm

all i

ncis

ion

in th

e po

ster

ior l

ens

caps

ule.

•Th

e vi

treou

s is

left

inta

ct a

nd th

e en

dola

ser

prob

e is

adv

ance

d fro

m th

e co

rnea

l inc

isio

n,

thro

ugh

the

tear

in th

e po

ster

ior l

ens

caps

ule

and

thro

ugh

the

vitre

ous

to th

e ar

ea o

f ret

ina

in

ques

tion.

•Th

is fi

lm is

cou

rtesy

of D

r Din

elli

Bras

, Pue

rto

Rico

•Th

e en

dola

ser c

an a

lso

be u

sed

afte

r in

traca

psul

ar le

ns e

xtra

ctio

n in

cas

es o

f ant

erio

r or

pos

terio

r len

s lu

xatio

n, to

insp

ect t

he

perip

hera

l ret

ina

and

lase

r any

retin

al te

ars

that

ar

e pr

esen

t.

•Ba

rrier

retin

opex

y ca

n be

per

form

ed b

y th

e tra

nssc

lera

l app

roac

h, h

owev

er, i

t is

actu

ally

qu

ite e

asy

to c

reat

e a

full

thic

knes

s ho

le in

the

retin

a an

d w

orse

n th

e de

tach

men

t

Com

plic

atio

ns o

f VR

surg

ery

Joe

Wol

fer

Toro

nto

Can

ada

•C

ompl

icat

ions

of V

R su

rger

y ca

n be

div

ided

into

in

traop

erat

ive

com

plic

atio

ns a

nd p

osto

pera

tive

com

plic

atio

ns.

•In

traop

erat

ive

com

plic

atio

ns in

clud

e bu

t are

not

lim

ited

to;

•Lo

ss o

f pro

ptos

is d

urin

g su

rger

y

•Th

e gl

obe

sudd

enly

dro

ps b

ack

into

the

orbi

t

•Th

is is

why

brid

le s

utur

es a

re p

lace

d at

3 a

nd 6

o’

cloc

k, to

qui

ckly

faci

litat

e re

prop

tosi

s of

the

glob

e

•Pl

acem

ent o

f the

infu

sion

por

t int

o th

e su

b re

tinal

sp

ace.

•If

the

fluid

s ar

e tu

rned

on

at th

is p

oint

, flui

d w

ill flo

w s

ub re

tinal

and

furth

er d

etac

h th

e re

tina

•Ve

ry im

porta

nt to

che

ck p

lace

men

t of t

he p

ort

befo

re in

itiat

ing

surg

ery

•C

horo

idal

hem

orrh

age

•O

ccur

s sp

onta

neou

sly

and

may

com

plet

ely

obsc

ure

view

of f

unds

•Th

e po

le is

rais

ed to

incr

ease

intra

ocul

ar

pres

sure

and

tam

pona

de th

e bl

eed

•Re

tain

ed p

erflu

oroc

tane

(PFO

)

•PF

O is

hig

hly

toxi

c to

the

retin

a an

d if

left

in th

e ey

e w

ill ca

use

retin

itis,

uve

itis

and

blin

dnes

s

•Re

tain

ed P

FO c

an a

lso

emul

sify

and

mig

rate

into

th

e an

terio

r cha

mbe

r cau

sing

uve

itis

and

dam

age

to th

e en

doth

elia

l sur

face

of t

he c

orne

a

•Po

stop

erat

ive

com

plic

atio

ns in

clud

e bu

t are

not

lim

ited

to;

•C

orne

al u

lcer

atio

n

•Pr

opto

sis

of th

e gl

obe

seem

s to

pre

disp

ose

to

corn

eal u

lcer

atio

n

•C

orne

a is

cov

ered

with

vis

coel

astic

dur

ing

the

surg

ery

•To

pica

l lub

ricat

ing

oint

men

t is

used

for o

ne w

eek

post

sur

gery

•G

lauc

oma

•Po

st o

pera

tive

ocul

ar h

yper

tens

ion

can

occu

r, es

peci

ally

if th

e ey

e is

ove

rfille

d w

ith s

ilicon

e oi

l

•To

pica

l car

boni

c an

hydr

ase

inhi

bito

rs a

re u

sed

lifel

ong

afte

r sur

gery

•Le

akag

e of

silic

one

oil i

nto

the

ante

rior c

ham

ber

can

occu

r pos

t ope

rativ

ely

espe

cial

ly if

ther

e is

an

y zo

nule

loss

aro

und

the

lens

•If

the

leak

age

is s

igni

fican

t eno

ugh

and

even

tual

ly re

sults

in d

ecom

pens

atio

n of

the

corn

eal e

ndot

helia

l cel

ls re

sulti

ng in

cor

neal

ed

ema,

it m

ust b

e re

mov

ed

•U

nder

gen

eral

ane

sthe

sia,

the

ante

rior c

ham

ber

is fi

lled

with

vis

coel

astic

, to

pres

suriz

e th

e fro

nt

of th

e ey

e, a

nd th

e si

licon

e oi

l is

“milk

ed” o

ut o

f th

e ey

e th

roug

h a

smal

l 20

g in

cisi

on m

ade

with

an

MVR

bla

de

•Si

licon

e oi

l will

also

som

etim

es le

ak fr

om th

e sc

lera

l wou

nds

into

a s

ubco

njun

ctiv

al lo

catio

n

•Th

is d

oes

not g

ener

ally

cau

se a

nyth

ing

but a

co

smet

ic p

robl

em a

nd th

e oi

l gen

eral

ly d

oes

not

need

to b

e re

mov

ed.

•Sl

ippa

ge o

f the

retin

a, u

nder

neat

h th

e si

licon

e oi

l, w

ill, in

rare

inst

ance

, occ

ur a

nd m

ay le

ad to

re

datc

hmen

t of t

he re

tina

•So

me

dogs

, yea

rs d

own

the

road

will

expe

rienc

e de

gene

ratio

n of

the

retin

a, th

at is

thou

ght

poss

ibly

to b

e du

e to

pre

senc

e of

silic

one

oil i

n th

e ey

e

•In

hum

an V

R su

rger

y, th

e si

licon

e oi

l is

gene

rally

re

mov

ed fr

om th

e ey

e af

ter a

bout

3 m

onth

s.

•Th

is is

ver

y di

fficu

lt an

d ex

pens

ive

to d

o in

the

dog,

so

the

silic

one

oil i

s ge

nera

lly le

ft in

pla

ce

for t

he li

fetim

e of

the

patie

nt

•To

try

and

prot

ect t

he re

tina,

pat

ient

s ar

e pu

t on

an o

ral c

alci

um c

hann

el b

lock

er (a

mlo

dipi

ne

0.62

5 m

g/5k

g) fo

r life

•So

met

imes

due

to s

ilicon

e oi

l lea

kage

, or f

or n

o ap

pare

nt re

ason

at a

ll, o

ne w

ill en

d up

with

an

inco

mpl

ete

silic

one

oil fi

ll.

•Th

is le

aves

the

vent

ral r

etin

a pr

one

to

rede

tach

men

t

•In

rare

inst

ance

s, fo

r a v

arie

ty o

f rea

sons

, the

re

tina

cann

ot b

e su

cces

sful

ly re

atta

ched

. Si

nce

we

know

that

chr

onic

retin

al d

etac

hmen

t lea

ds to

pr

e-iri

dal fi

brov

ascu

lar m

embr

ane

(PIF

M)

form

atio

n an

d ne

ovas

cula

r gla

ucom

a, I

will

usua

lly a

t tha

t poi

nt, p

erfo

rm a

com

plet

e re

tinec

tom

y (re

mov

al o

f the

retin

a)

•Th

e ey

e is

then

fille

d w

ith s

ilicon

e oi

l as

usua

l.

29/09/2017

1

BrAVO discussion 2017 ‘How I treat….’

SCCEDs

David Gould

BSc (Hons), BVM&S, PhD, DVOphthal, DipECVO, FRCVS

Davies Veterinary Specialists

Spontaneous Chronic Corneal Epithelial Defect (SCCED)

Shallow, epithelial loss only

Underrun edges

Older dogs

Ineffective vascularisation response

29/09/2017

2

Anterior corneal anatomy

1 Epithelium

2 Basement membrane

3 Anterior stroma

Integrins, hemidesmosomes

Anchoring fibrils

(VII collagen)

BM

Stroma

Epithelium

Anchoring plaque

(laminin, I collagen)

Adhesion complex fibronectin

Pathology of SCCED

• Reduction/ loss of

hemidesmosomes, BM and

adhesion complexes

• Hyper-innervation

•Hyalinized layer anterior stroma

Integrins, hemidesmosomes

Anchoring fibrils

(VII collagen)

BM

Stroma

Epithelium

Anchoring plaque

(laminin, I collagen)

fibronectin

29/09/2017

3

Medical treatments?

Serine protease inhibitors

Tetracyclines

Serum

Serine Protease inhibitors?

Theory

Increased proteolysis occurs in chronic ulcers

• Erosion of ECM proteins

• Delayed healing

SP inhibitors may counteract this

C o l l a g e n o l y s i s

MMPs Serine proteases

29/09/2017

4

Evidence?

Debridement + aminocaproic acid for SCCEDs (Regnier et al Vet Record 2005)

At 3 weeks • ACA 94% healed

• Controls 41% healed

C o l l a g e n o l y s i s

MMPs Serine proteases

Serine Protease inhibitors?

Evidence?

Debridement + aminocaproic acid for SCCEDs (Regnier et al Vet Record 2005)

At 3 weeks • ACA 94% healed

• Controls 41% healed

Critique

Control Tx was gentamicin

Not all SCCEDs show elevated proteolysis (Willeford et al VO 1998)

C o l l a g e n o l y s i s

MMPs Serine proteases

Serine Protease inhibitors?

29/09/2017

5

Tetracyclines?

Theory Doxycycline and tetracycline

inhibit MMPs in vitro and in equine tears

Oxytetracycline upregulates TGF-β in corneal epith cells and promotes migration

(Chandler et al Exp Eye Res 2007)

C o l l a g e n o l y s i s

MMPs Serine proteases

Tetracyclines?

Evidence Following grid keratotomy,

topical oxytetacycline shortens healing time compared to controls or those treated with oral

doxycycline (Chandler et al JAVMA 2010)

Critique Recent study reported opposite

Slower healing time with OTC cf ofloxacin

(Dees et al 2017)

C o l l a g e n o l y s i s

MMPs Serine proteases

29/09/2017

6

Serum?

Theory

Contains antiproteases, fibronectin…

May reduce collagenolysis and supply glycoproteins for wound healing

C o l l a g e n o l y s i s

MMPs Serine proteases

serum

Serum?

Critique

No reported studies for SCCEDs

Fibronectin already at wound site

C o l l a g e n o l y s i s

MMPs Serine proteases

serum

29/09/2017

7

Medical treatments

Conclusion

No evidence for serum

OTC reduces healing time in 1 study, prolongs it in another

Aminocaproic acid reported effective

• Commercial availability?

Surgical treatment of SCCED

Technique

Debridement

Grid /punctate keratotomy

Diamond burr/ Algerbrush

Thermokeratoplasty

Superficial keratectomy

Success rate

~50%

~ 80%

92%

100%

100% (Bentley JAAHA 2005, Gosling et al VO 2013, Dees et al 2017)

29/09/2017

8

My approach?

Diamond burr once, perhaps twice

i/v sedation Butorphanol 0.2mg/kg i/v bolus

Medetomidine 10ug/kg, diluted in 5mls saline and given to effect

My approach?

Diamond burr once, perhaps twice

i/v sedation Butorphanol 0.2mg/kg i/v bolus

Medetomidine 10ug/kg, diluted in 5mls saline and given to effect

Contact lens

Chloramphenicol, ± lubricants, systemic NSAIDs

29/09/2017

9

My approach?

Diamond burr once, perhaps twice

i/v sedation Butorphanol 0.2mg/kg i/v bolus

Medetomidine 10ug/kg, diluted in 5mls saline and given to effect

Contact lens

Chloramphenicol, ± lubricants, systemic NSAIDs

3 weeks between procedures

If possible, SK before vascularisation

Questions?

29/09/2017

10

Refs: Medical treatment of SCCED

Treatment Success rate Reference

Protease inhibitors

Aprotinin 33% PSGAG 82% Aminocaproic acid 94% Serum?

Morgan & Abrams VCO 1994, Miller VetMed 1996, Willeford et al VO 1998, Regnier et al VR 2005

Substance P 70% Murphy et al IOVS 2001

Epidermal GF 80% Kirschner et al VCNA 1991

Chondroitin sulfate 81% Ledbetter et al Prog ACVO 2003

Tetracyclines

N/A Chandler et al JAVMA 2010

Refs: Surgical treatment of SCCED

Treatment Success rate Reference

Debridement ≈ 50% Kirschner et al VCNA 1991, Morgan et al VCO 1994, Stanley et al VO 1998

Debridement + BCL or TEF

58-64% Morgan et al VCO 1994

Debridement + punctate/ grid keratotomy

68-88% Champagne et al JAAHA 1992, Morgan et al VCO 1994, Stanley et al VO 1998

Diamond burr + BCL 92% Gosling et al VO 2013 Dees et al VO 2017

Thermal cautery 100% Bentley and Murphy JAVMA 2004

Superficial keratectomy 100% Stanley et al VO 1998

LENS LUXATION

ClaudiaHartleyBVScCertVOphthalDipECVOMRCVS

LENSLUXATIONIntroducAonFirstdescribedinacasereportin1969ThenaseriesofpapersbyRogerCurAs–bodyofworkonprimarylensluxaAon1978-1990Histopathology-Morris&DubielzigTreatment–Gloveretal,O’Reillyetal,Binderetal,Wilkieetal,Stuhretal,Montgomeryetal,Inheritance–Willisetal,CurAsetal,LazarusetalGeneAcs–Sarganetal,Fariasetal,Gouldetal

LENSLUXATIONPrimarylensluxaAonDisintegraAonofzonulesProgressivelooseningofthelensIridodenesisVitrealprolapsePhacodenesisAnteriorlensluxaAonPosteriorlensluxaAon

JRTTibetanterrierSharpeiBordercollieMiniaturebullterriermutaAonADAMTS17

•  Suspension•  zonules

Lens

•  Suspension•  zonules

Lens

•  Pathogenesis•  degeneratezonules

Lens

•  LensluxaAon/subluxaAon

aphakiccrescentvitreousprolapse

anteriorposterior

cataract

Lens

•  LensluxaAon/subluxaAon

inheriteddefect(s)trauma2’glaucoma

Lens

•  LensluxaAon/subluxaAon

treatment•  Surgery•  IntracapsularlensextracAon(ICLE)•  PhacoemulsificaAon

Lens

MedicalCouchingProstaglandinanalogue

•  LensluxaAon/subluxaAon

treatment•  Surgery•  IntracapsularlensextracAon(ICLE)•  PhacoemulsificaAon

Lens

MedicalCouchingProstaglandinanalogue

•  LensluxaAon/subluxaAon

treatment•  Surgery•  IntracapsularlensextracAon(ICLE)•  PhacoemulsificaAon

Lens

MedicalCouchingProstaglandinanalogue

TLGlover,MGDavidson,MPNasisse,andDKOlivero(1995)TheintracapsularextracAonofdisplacedlensesindogs:aretrospecAvestudyof57cases(1984-1990).JournaloftheAmericanAnimalHospitalAssocia7on:January1995,Vol.31,No.1,pp.77-81.

•  LensluxaAon/subluxaAon

treatment•  Surgery•  IntracapsularlensextracAon(ICLE)•  PhacoemulsificaAon

Lens

MedicalCouchingProstaglandinanalogue

Intracapsular lensectomy and sulcus intraocular lens fixationin dogs with primary lens luxation or subluxation

Charles M. Stuhr, Hillary K. Schilke and Christina ForteAnimal Eye Clinic, 2 Pimpewaug Rd., Wilton, CT 06897, U.S.A.

Address communications to:

C. M. Stuhr

Tel.: (203) 762-9399

Fax: (203) 762-2775

e-mail: cstuhr@snet.net

AbstractObjective To evaluate the postoperative results of lensectomy and sulcus intraocularlens fixation (SIOLF) via an ab interno approach in dogs with progressive lens

subluxation or early luxation.Study design Retrospective study.Animals studied Twenty eyes from 19 dogs presented to the Animal Eye Clinic for

lens luxation or subluxation between 1999 and 2006.Methods Medical records were reviewed to evaluate preoperative lens position, vision

status, intraocular pressure (IOP), and whether surgery was performed on anemergent or elective nature. Lensectomy and SIOLF were performed and

postoperative status including vision, glaucoma, and retinal detachment was assessed.Results Average age was 8.6 years (range 4–14 years) and 55% (11/20) were terriers.

Patients were followed a mean of 29.2 months (range 1–92 months) after surgery.Retinal detachment or secondary glaucoma was observed in 1 of 20 (5%) and 5 of 20(20%) eyes, respectively, with 1 of 20 (5%) exhibiting both. Mean preoperative IOP

was 16 mmHg and preoperative lens position was equally divided between luxatedand subluxated lenses. Surgery was performed more frequently as an elective

procedure (18/20; 90%) due to normalized IOP vs. an emergency procedure (2/20;10%). Vision was retained in 70% (14/20) of eyes with a mean time to vision loss of

41 months in the remaining eyes due to glaucoma, retinal detachment, or retinaldegeneration.

Conclusions Complications of glaucoma and retinal detachment after SIOLF in thisstudy were less when compared with previously reported incidence rates in the

literature for lensectomy alone which may reflect improved patient selection.

Key Words: lens, lensectomy, luxation, subluxation, sulcus IOL

INTRODUCTION

Acute lens luxation with an associated rapid pressure spike isone of the true surgical emergencies in veterinary ophthal-mology.1 Surgical repair by lensectomy alone or with pri-mary placement of a sulcus-fixated intraocular lens (SIOLF)has been described previously in the veterinary literaturewith only a modicum of long-term success in a limited num-ber of publications.2–4 Complications, primarily retinaldetachment and secondary glaucoma, are not uncommonand are typically associated with irreversible vision loss.1 Asthis surgery is commonly performed on an emergency basiswhen the lens presents in the anterior chamber with a pupil-lary block glaucoma, the intraocular inflammatory response

and its cascade of destructive events have already been initi-ated, which may contribute to postoperative failure. There-fore, early surgical intervention has been advised by some inefforts to minimize these postoperative complications.2,3

In recent years, the goals of intraocular lenticular surgery,primarily cataract extraction, have been focused on achiev-ing a comfortable, sighted eye that is emmetropic.5,6

Emmetropia is achieved by placement of an intraocular lens(IOL) made of polymethylmethacrylate (PMMA) or acrylicinto the capsular bag that remains after routine phacoemul-sification. IOL placement is not possible in intracapsularlensectomy repair without sulcus fixation. Routine place-ment of an IOL after lensectomy has not achieved universalacceptance due to the perceived increase in postoperative

� 2009 American College of Veterinary Ophthalmologists

Veterinary Ophthalmology (2009) 12, 6, 357–360

•  LensluxaAon/subluxaAon

treatment•  Surgery•  IntracapsularlensextracAon(ICLE)•  PhacoemulsificaAon

Lens

MedicalCouchingProstaglandinanalogue

SM

ALL A

NIM

ALS

JAVMA, Vol 231, No. 1, July 1, 2007 Scientific Reports: Retrospective Study 89

Lens luxation is a well-recognized clinical disorder in dogs, and common causes include primary lens

zonule disease (primary lens luxation), senescence, and hypermature cataracts.1 Other causes include glau-coma, uveitis, and trauma.1 Canine primary lens luxa-tion is characterized by spontaneous rupture of lens zonules, resulting in lens instability and eventual luxa-tion.1,2 A heritable pattern of disease has been estab-lished in a number of breeds, including various terrier breeds, Shar Peis, and Border Collies, although numer-ous other dog breeds have been suggested to be affected by primary lens luxation.2-11 Although canine primary lens luxation is invariably bilateral, complete lens dis-location generally occurs in 1 eye some time (days to months) before the other eye.1,2,12

Vision-threatening complications of lens luxation include glaucoma and, less commonly, retinal detach-ment. Other complications include uveitis and intraoc-ular hemorrhage. Glaucoma may develop in eyes with

Outcomes of nonsurgical management and efficacy of demecarium bromide treatment

for primary lens instability in dogs: 34 cases (1990–2004)

Daniel R. Binder, DVM, PhD; Ian P. Herring, DVM, MS, DACVO; Tobias Gerhard, BS

From the Department of Small Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061-442 (Binder, Herring); and the Department of Pharmacy Health Care Administration, University of Florida, Gainesville, FL 32610-0496 (Gerhard).

Presented in part at the American College of Veterinary Ophthal-mologists Annual Meeting, Washington, DC, October 2004.

Address correspondence to Dr. Herring.

Objective—To determine outcome of initial conservative management for primary lens luxation and evaluate topically administered demecarium bromide miotic treatment for pre-vention of anterior lens luxation, glaucoma, and vision loss in dogs.Design—Retrospective case series.Animals—34 dogs with primary lens luxation.Procedures—Medical records of affected dogs were reviewed for times to anterior luxa-tion, luxation of the lens in the opposite eye, development of glaucoma, and vision loss. Results—At 4 to 6 weeks and at 3 months after diagnosis of lens instability (subluxation or posterior luxation), 100% (34/34 and 29/29, respectively) of conservatively managed eyes retained vision. At 1 year after diagnosis of lens instability, 80% (16/20) of conservatively managed eyes retained vision, and at 2 years after diagnosis of lens instability, 11 of 19 conservatively treated eyes retained vision. The only significant effect of miotic treatment was to delay anterior lens luxation in eyes with lens instability. Miotic treatment did not sig-nificantly affect the time from anterior lens luxation in 1 eye to anterior luxation in the other eye, time to onset of glaucoma, or time to loss of vision in eyes with an unstable lens.Conclusions and Clinical Relevance—Prophylactic topically administered miotic treat-ment may be effective at delaying anterior luxation of an unstable lens in eyes affected by primary lens instability. Conservative medical management of dogs with primary lens insta-bility is a reasonable alternative to surgical removal of a subluxated or posteriorly luxated lens via intracapsular lens extraction. (J Am Vet Med Assoc 2007;231:89–93)

ABBREVIATION

ICLE Intrascapular lens extraction

primary lens instability, regardless of lens position.4,10 Although it is more common for this complication to develop when the lens is displaced into the anterior chamber, it also occurs in a large percentage of eyes with lens subluxation.4,10

Because of the high likelihood of developing sec-ondary glaucoma with subsequent vision loss, anterior lens luxation is considered an ocular emergency requir-ing prompt lens removal via ICLE. In dogs with anterior lens luxation, careful evaluation of the opposite eye of-ten reveals evidence of a subluxated or posteriorly lux-ated lens, which may include vitreous in the anterior chamber, abnormal anterior chamber depth, iridoden-esis, lentodenesis, or an aphakic crescent.1 Although it is widely accepted that prompt ICLE is indicated for an-terior lens luxation, the most appropriate management approach to lenses that are subluxated or posteriorly luxated is unclear.

Broadly speaking, management of a subluxated or posteriorly luxated lens may include surgical ex-traction or a more conservative approach of waiting until anterior luxation occurs prior to surgical inter-vention. Advocates of surgical removal of a sublux-

•  LensluxaAon/subluxaAon

treatment•  Surgery•  IntracapsularlensextracAon(ICLE)•  PhacoemulsificaAon

Lens

MedicalCouchingProstaglandinanalogue

TLGlover,MGDavidson,MPNasisse,andDKOlivero(1995)TheintracapsularextracAonofdisplacedlensesindogs:aretrospecAvestudyof57cases(1984-1990).JournaloftheAmericanAnimalHospitalAssocia7on:January1995,Vol.31,No.1,pp.77-81.

•  LensluxaAon/subluxaAon

Lens

MedicalCouchingProstaglandinanalogue

InheritanceToy/headshaking

•  Bears•  PinnipedsandOtariids•  Matshchie’streekangaroo

LensLuxaAoninWildAnimals

•  Bears•  PinnipedsandOtariids•  Matshchie’streekangaroo

LensLuxaAoninWildAnimals

JAVMA, Vol 237, No. 4, August 15, 2010 Scientific Reports 429

AQ

UATIC

AN

IMA

LS

Diseases of the cornea and lens are common in captive pinnipeds; environmental factors including water qual-

ity and salinity, light intensity, nutrition, and spatial charac-teristics (eg, orientation of sun on wet and dry areas, depth, exhibit surface color [for reflected light], and animal loading per cubic meter [because of potential water-quality effects]) have been reporteda as the most likely predominant causes. On the basis of results of a study by Dunn et al,b most captive pinnipeds are now housed in saltwater rather than freshwater. However, other factors have been more difficult to implicate as direct causes of ocular disease. There are few published studies1–3 that characterize the ocular changes observed in captive pinnipeds or attempt to identify environmental influ-ences on lens health in these species.

One of the goals of the study reported here was to iden-tify the incidence of lens luxations and cataracts in selected

Risk factors associated with cataracts and lens luxations in captive pinnipeds in the United States and the Bahamas

Carmen M. H. Colitz, DVM, PhD, DACVO; William J. A. Saville, DVM, PhD, DACVIM; Michael S. Renner, DVM; James F. McBain, DVM; Thomas H. Reidarson, DVM, DACZM; Todd L. Schmitt, DVM;

Elizabeth C. Nolan, DVM, MS, DACZM; Steven J. Dugan, DVM, MS, DACVO; Felicia Knightly, DVM; Maya M. Rodriguez, DVM; Johanna C. Mejia-Fava, DVM; Steven D. Osborn, DVM;

Patricia L. Clough, MAT; Scott P. Collins, BS; Beverly A. Osborn, BS; Kimberly Terrell, BS

Objective—To determine risk factors for lens luxation and cataracts in captive pinnipeds in the United States and the Bahamas.Design—Cross-sectional study.Animals—111 pinnipeds (99 California sea lions [Zalophus californianus], 10 harbor seals [Phoca vitulina], and 2 walruses [Odobenus rosmarus]) from 9 facilities.Procedures—Eyes of each pinniped were examined by a veterinary ophthalmologist for the presence of cataracts or lens luxations and photographed. Information detailing husbandry practices, history, and facilities was collected with a questionnaire, and descriptive statisti-cal analyses were performed for continuous and categorical variables. Odds ratios and as-sociated 95% confidence intervals were estimated from the final model.Results—Risk factors for lens luxation, cataracts, or both included age 15 years, history of fighting, history of ocular disease, and insufficient access to shade.Conclusions and Clinical Relevance—Diseases of the lens commonly affect captive pinnipeds. Access to UV-protective shade, early identification and medical management of ocular diseases, and prevention of fighting can limit the frequency or severity of lens-related disease in this population. An extended life span may result from captivity, but this also allows development of pathological changes associated with aging, including cataracts. (J Am Vet Med Assoc 2010;237:429–436)

populations of captive pinnipeds. The authors also sought to identify risk factors that may have a role in the development of lens luxations or cataracts in captive pinnipeds. Califor-nia sea lions (Zalophus californianus) are the most common captive pinniped in most facilities and, consequently, were analyzed as a separate subset of pinnipeds.

Materials and Methods

Animals—One hundred eleven captive pinnipeds of both sexes (99 California sea lions, 10 harbor seals [Phoca

From the Departments of Veterinary Clinical Sciences (Colitz) and Veterinary Preventive Medicine (Saville), College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210; Dolphin Research Center, 58901 Overseas Hwy, Grassy Key, FL 33050 (Renner, Clough); Theater of the Sea, 84721 Overseas Hwy, Islamorada, FL 33036 (Renner, BA Osborn); Busch Entertainment Corporation, 500 SeaWorld Dr, San Diego, CA 92109 (McBain); SeaWorld San Diego, 500 SeaWorld Dr, San Diego, CA 92109 (Reidarson, Schmitt, Collins); SeaWorld Orlando, 7007 Sea Harbor Dr, Orlando, FL 32821 (Nolan); Eye Specialists for Animals PC, 4175 E Iliff Ave, Denver, CO 80222 (Dugan); Denver Zoo, 2300 Steele St, Denver, CO 80205 (Knightly); The Miami Seaquarium, 4400 Rickenbacker Causeway, Miami, FL 33149 (Rodriguez, Mejia-Fava); SeaWorld San Antonio, 10500 SeaWorld Dr, San Antonio, TX 78251 (SD Osborn); and Dolphin Encounters Limited, PO Box SS 6257, Nassau, SS19055, Bahamas (Terrell). Dr. Reidarson’s present address is Reidarson Group, Sea Aquarium, Netherlands Antilles. Ms. Nolan’s present address is Disney’s Animal Programs, Walt Disney World, 1000 W Buena Vista Dr, Lake Buena Vista, FL 32830.

Supported by the Columbus Zoo and The Ohio State University.The authors thank Pamela Ollen-Hughes and Sarah Jayne Buchanan for technical assistance.Address correspondence to Dr. Colitz (ccolitz@gmail.com).

ABBREVIATIONS

LEC Lens epithelial cellMMP Matrix metalloproteinase

JAVMA, Vol 237, No. 4, August 15, 2010 Scientific Reports 429

AQ

UATIC

AN

IMA

LS

Diseases of the cornea and lens are common in captive pinnipeds; environmental factors including water qual-

ity and salinity, light intensity, nutrition, and spatial charac-teristics (eg, orientation of sun on wet and dry areas, depth, exhibit surface color [for reflected light], and animal loading per cubic meter [because of potential water-quality effects]) have been reporteda as the most likely predominant causes. On the basis of results of a study by Dunn et al,b most captive pinnipeds are now housed in saltwater rather than freshwater. However, other factors have been more difficult to implicate as direct causes of ocular disease. There are few published studies1–3 that characterize the ocular changes observed in captive pinnipeds or attempt to identify environmental influ-ences on lens health in these species.

One of the goals of the study reported here was to iden-tify the incidence of lens luxations and cataracts in selected

Risk factors associated with cataracts and lens luxations in captive pinnipeds in the United States and the Bahamas

Carmen M. H. Colitz, DVM, PhD, DACVO; William J. A. Saville, DVM, PhD, DACVIM; Michael S. Renner, DVM; James F. McBain, DVM; Thomas H. Reidarson, DVM, DACZM; Todd L. Schmitt, DVM;

Elizabeth C. Nolan, DVM, MS, DACZM; Steven J. Dugan, DVM, MS, DACVO; Felicia Knightly, DVM; Maya M. Rodriguez, DVM; Johanna C. Mejia-Fava, DVM; Steven D. Osborn, DVM;

Patricia L. Clough, MAT; Scott P. Collins, BS; Beverly A. Osborn, BS; Kimberly Terrell, BS

Objective—To determine risk factors for lens luxation and cataracts in captive pinnipeds in the United States and the Bahamas.Design—Cross-sectional study.Animals—111 pinnipeds (99 California sea lions [Zalophus californianus], 10 harbor seals [Phoca vitulina], and 2 walruses [Odobenus rosmarus]) from 9 facilities.Procedures—Eyes of each pinniped were examined by a veterinary ophthalmologist for the presence of cataracts or lens luxations and photographed. Information detailing husbandry practices, history, and facilities was collected with a questionnaire, and descriptive statisti-cal analyses were performed for continuous and categorical variables. Odds ratios and as-sociated 95% confidence intervals were estimated from the final model.Results—Risk factors for lens luxation, cataracts, or both included age 15 years, history of fighting, history of ocular disease, and insufficient access to shade.Conclusions and Clinical Relevance—Diseases of the lens commonly affect captive pinnipeds. Access to UV-protective shade, early identification and medical management of ocular diseases, and prevention of fighting can limit the frequency or severity of lens-related disease in this population. An extended life span may result from captivity, but this also allows development of pathological changes associated with aging, including cataracts. (J Am Vet Med Assoc 2010;237:429–436)

populations of captive pinnipeds. The authors also sought to identify risk factors that may have a role in the development of lens luxations or cataracts in captive pinnipeds. Califor-nia sea lions (Zalophus californianus) are the most common captive pinniped in most facilities and, consequently, were analyzed as a separate subset of pinnipeds.

Materials and Methods

Animals—One hundred eleven captive pinnipeds of both sexes (99 California sea lions, 10 harbor seals [Phoca

From the Departments of Veterinary Clinical Sciences (Colitz) and Veterinary Preventive Medicine (Saville), College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210; Dolphin Research Center, 58901 Overseas Hwy, Grassy Key, FL 33050 (Renner, Clough); Theater of the Sea, 84721 Overseas Hwy, Islamorada, FL 33036 (Renner, BA Osborn); Busch Entertainment Corporation, 500 SeaWorld Dr, San Diego, CA 92109 (McBain); SeaWorld San Diego, 500 SeaWorld Dr, San Diego, CA 92109 (Reidarson, Schmitt, Collins); SeaWorld Orlando, 7007 Sea Harbor Dr, Orlando, FL 32821 (Nolan); Eye Specialists for Animals PC, 4175 E Iliff Ave, Denver, CO 80222 (Dugan); Denver Zoo, 2300 Steele St, Denver, CO 80205 (Knightly); The Miami Seaquarium, 4400 Rickenbacker Causeway, Miami, FL 33149 (Rodriguez, Mejia-Fava); SeaWorld San Antonio, 10500 SeaWorld Dr, San Antonio, TX 78251 (SD Osborn); and Dolphin Encounters Limited, PO Box SS 6257, Nassau, SS19055, Bahamas (Terrell). Dr. Reidarson’s present address is Reidarson Group, Sea Aquarium, Netherlands Antilles. Ms. Nolan’s present address is Disney’s Animal Programs, Walt Disney World, 1000 W Buena Vista Dr, Lake Buena Vista, FL 32830.

Supported by the Columbus Zoo and The Ohio State University.The authors thank Pamela Ollen-Hughes and Sarah Jayne Buchanan for technical assistance.Address correspondence to Dr. Colitz (ccolitz@gmail.com).

ABBREVIATIONS

LEC Lens epithelial cellMMP Matrix metalloproteinase

•  Bears•  PinnipedsandOtariids•  Matshchie’streekangaroo

LensLuxaAoninWildAnimals

•  Bears•  PinnipedsandOtariids•  Matshchie’streekangaroo

LensLuxaAoninWildAnimals

NY, USA). The ophthalmic examination findings includedminimal direct and consensual pupillary light reflexes inboth eyes (OU) and the intraocular pressures were29 mmHg OD and 33 mmHg OS. The menace responsesand dazzle reflexes were negative, and this was attributedto the deep level of sedation. A small nictitating mem-brane was noted, extending dorsotemporally from the ven-tromedial aspect of the orbit OU. There was a focal areaof full-thickness corneal edema immediately ventral ofaxial in the right eye. The pupils were round, the irideswere dark brown, and a corpora nigra was not presentOU. In the right eye, the lens was anteriorly luxated andthere was an early immature anterior cortical cataract. Inthe left eye, the lens was clear but was subluxated and anaphakic crescent was present dorsotemporally. Iridodone-sis was not present in either eye and neither iris appearedto be hyperpigmented when compared to those of anothertree kangaroo. The retina and optic discs were visibleOU. The optic discs were similar OU and were roundand pale pink in color. A small tuft of vessels was presenton the surface of the optic discs OU but retinal blood ves-sels were not present (paurangiotic retinal vascular pat-tern).4 Clinically, the appearance of the posterior segmentwas similar to that of the guinea pig. A tapetum lucidumwas not present and the retinal pigmented epitheliumappeared to be only partially pigmented creating a red huefrom the underlying choroidal vessels. A complete bloodcell count and biochemistry panel were performed, andthe results were normal. Based on the exam findings, theanimal was diagnosed with an anterior lens luxation ODand a lens subluxation OS. Although the normal range ofintraocular pressures has not been established for this spe-cies, ocular hypertension was also suspected because themeasured pressures were higher than the normal valuesreported for other marsupials.5 Intracapsular lens extractionwas recommended OU. Surgical removal of both lensessimultaneously was considered, but the decision was madeto operate on each eye individually due to concern over thelength of the anesthetic event needed for bilateral surgeryand transport to the surgical facility. No medications wereprescribed prior to surgery because the zookeepers couldnot safely administer topical medications.Forty-one days after the initial exam, the animal was

again immobilized by intramuscular injection using thesame drug combination used for the initial exam and wasthen intubated and maintained under general anesthesiawith isoflurane. The animal was transported under anes-thesia to the surgical facility for a planned intracapsularlens extraction OD. Topical ciprofloxacin 0.3% ophthal-mic solution (Akorn Inc., Lake Forest, IL, USA) and topi-cal neomycin, polymyxin, dexamethasone solution (AlconLab Inc., Fortworth, TX, USA) were administered topi-cally every 5 min (3 drops of each) during transport. Anocular exam found an absence of direct and consensualpupillary light reflexes in both eyes and intraocular pres-sures of 23 mmHg OD and 21 mmHg OS. Other changes

from the initial exam included resolution of the previouslynoted corneal edema OD, progression of the cataract ODto a mature cataract, posterior movement of the lens ODinto the patellar fossa with a nasal aphakic crescent(Fig. 1), enlargement of the aphakic crescent OS, and anearly immature anterior cortical cataract OS. Because theintraocular pressures were elevated at the initial exam,consideration was given to the fact that the lens luxationscould be secondary to chronic glaucoma and buphthalmia.If this were the case, glaucomatous retinal degenerationwould be expected. Thus, a flash electroretinogram (ERG)(BPM-200; Retinographics, Inc., Norwalk, CT, USA) wasperformed OU. The ERGs were performed after 5 min ofdark adaptation. The time permitted for dark adaptionwas shortened from the more typical 15 min due to adesire to limit the length of general anesthesia. The pupilswere not dilated for the ERG due to the lenticular insta-bility. Normal a- and b-waves were apparent when com-pared to other mammals.6 A-wave amplitudes were 51 lVOD and 29 lV OS and the a-wave implicit times were21 ms OD and 19 ms OS. B-wave amplitudes were111 lV OD and 62 lV OS (b-wave reference range>100 lV in our electrodiagnostic laboratory for dogs;ERG values for normal tree kangaroos have not beenestablished) and the b-wave implicit times were 44 ms ODand 39 ms OS. The lower b-wave amplitude OS wasattributed to the lack of pupillary dilation although retinaldegeneration could not be definitively excluded. The rightpupil was more dilated than the left presumably due tomechanical interference from the luxated lens.The right eye was aseptically prepared for surgery.

Atracurium (0.1 mg/kg; Sagent Pharmaceuticals, Inc.,Schaumburg, IL, USA) was administered intravenously tocentralize the globe, and the animal was mechanically ven-tilated; this single dose provided adequate globe centrationfor the procedure. An intracapsular lens extraction wasperformed using an operating microscope (OPMI VISU

Figure 1. Photograph of the right eye immediately prior to

intracapsular lens extraction. Note the mature cataract and temporal

aphakic cresent.

© 2014 American College of Veterinary Ophthalmologists, Veterinary Ophthalmology, 18, 81–85

82 MC L E AN AND Z IMM E RMAN

CASE REPORT

Bilateral lens luxation and intracapsular lens extractionsin a Matshchie’s tree kangaroo

Nancy Johnstone McLean* and Ralph Zimmerman†*VCA Veterinary Care Animal Hospital and Referral Center, 9901 Montgomery Boulevard NE, Albuquerque, NM, 87111, USA;

and †ABQ Biopark, Rio Grande Zoo, 903 Tenth St. SW, Albuquerque, NM, 87102, USA

Address communications to:

N. J. McLean

Tel.: +1 505-296-2982

Fax: +1 866-822-2573

e-mail: nancyjmclean@gmail.

com

AbstractAn adult, female, captive, Matshchie’s tree kangaroo was diagnosed with an anteriorlens luxation in the right eye and a lens subluxation in the left eye. Both eyes were

treated surgically with intracapsular lens extractions. A 360° rhegmatogenous retinaldetachment was diagnosed 6 months postoperatively in the left eye. Aphakic vision

was maintained in the right eye 9 months postoperatively. Based on family history andthe lack of antecedent ocular disease, the lens luxations were presumed to be inherited

and veterinarians should be aware of this condition within the captive tree kangaroopopulation.

Key Words: intracapsular lens extraction, lens luxation, marsupial, Matshchie’s treekangaroo, veterinary, zoo

INTRODUCTION

Matshchie’s tree kangaroo (Dendrolagus mastchiei) is anarboreal marsupial native to Papua New Guinea. The spe-cies belongs to the family Macropodidae and is found onlyat high altitudes in the rainforests in the Huon Peninsulaof Papua New Guinea. Matshchie’s tree kangaroo isendangered due to habitat destruction and hunting. Thecaptive population was established from 19 individuals,but only four females contribute to the majority of theoffspring.1 The captive tree kangaroo in this case report isone of the few cycling females in captivity and is, thus, animportant player in the preservation of this species.Because this population is so small and importation ofadditional animals from the wild is restricted, the genepool is limited and there is a significant founder effect.1

With limited genetic diversity, the risk of inherited dis-eases increases and this case report documents bilaterallens luxations in a Matshchie’s tree kangaroo that aresuspected to be hereditary.With the exception of one report of retinal degenera-

tion in a captive Goodfellow’s tree kangaroo (Dendrolagusgoodfellowii) and a description of retinal ganglion celltopography in Doria’s tree kangaroo (Dendrolagus doriana),there are no reports within the veterinary literature detail-ing normal ocular anatomy, pathologic ocular conditions,or the treatment of ocular disease in this species.2,3 We

present a case of bilateral lens luxations and cataracts in acaptive Matshchie’s tree kangaroo that were addressed sur-gically with bilateral intracapsular lens extraction. Becausethe gene pool for this population is small, this problemmay become more prevalent within the captive populationin the United States.

CASE REPORT

A 7-year-old female captive Matschie’s tree kangaroo(Dendrolagus mastchiei) was evaluated because her zoo-keeper and the zoo veterinarian had noted an opacity inthe right eye (OD). The animal could not be handledawake and was immobilized by an intramuscular injectionof a combination of medetomidine (62 mcg/kg; Zoo-Pharm, Laramie, WY, USA), ketamine (3.9 mg/kg; Boeh-ringer-IngelheimVetmedica Inc., St. Joseph, MO, USA),and butorphanol (0.13 mg/kg; Torbugesic, Fort DodgeAnimal Health, Fort Dodge, IA, USA) delivered via aremote delivery system (Telinject 1763 Air Pistol, AguaDulce, CA, USA). The animal was placed in sternalrecumbency for the ophthalmic exam which included dif-fuse illumination (transilluminator), slit-lamp biomicrosco-py (SL-15; Kowa Company, Tokyo, Japan) and indirectfunduscopy (Keeler Vantage Plus; Broomall, PA, USA).The intraocular pressure (IOP) was estimated using appla-nation tonometry (Tono-pen Vet; Reichert Inc., Depew,

© 2014 American College of Veterinary Ophthalmologists

Veterinary Ophthalmology (2015) 18, Supplement 1, 81–85 DOI:10.1111/vop.12207

CASE REPORT

Bilateral lens luxation and intracapsular lens extractionsin a Matshchie’s tree kangaroo

Nancy Johnstone McLean* and Ralph Zimmerman†*VCA Veterinary Care Animal Hospital and Referral Center, 9901 Montgomery Boulevard NE, Albuquerque, NM, 87111, USA;

and †ABQ Biopark, Rio Grande Zoo, 903 Tenth St. SW, Albuquerque, NM, 87102, USA

Address communications to:

N. J. McLean

Tel.: +1 505-296-2982

Fax: +1 866-822-2573

e-mail: nancyjmclean@gmail.

com

AbstractAn adult, female, captive, Matshchie’s tree kangaroo was diagnosed with an anteriorlens luxation in the right eye and a lens subluxation in the left eye. Both eyes were

treated surgically with intracapsular lens extractions. A 360° rhegmatogenous retinaldetachment was diagnosed 6 months postoperatively in the left eye. Aphakic vision

was maintained in the right eye 9 months postoperatively. Based on family history andthe lack of antecedent ocular disease, the lens luxations were presumed to be inherited

and veterinarians should be aware of this condition within the captive tree kangaroopopulation.

Key Words: intracapsular lens extraction, lens luxation, marsupial, Matshchie’s treekangaroo, veterinary, zoo

INTRODUCTION

Matshchie’s tree kangaroo (Dendrolagus mastchiei) is anarboreal marsupial native to Papua New Guinea. The spe-cies belongs to the family Macropodidae and is found onlyat high altitudes in the rainforests in the Huon Peninsulaof Papua New Guinea. Matshchie’s tree kangaroo isendangered due to habitat destruction and hunting. Thecaptive population was established from 19 individuals,but only four females contribute to the majority of theoffspring.1 The captive tree kangaroo in this case report isone of the few cycling females in captivity and is, thus, animportant player in the preservation of this species.Because this population is so small and importation ofadditional animals from the wild is restricted, the genepool is limited and there is a significant founder effect.1

With limited genetic diversity, the risk of inherited dis-eases increases and this case report documents bilaterallens luxations in a Matshchie’s tree kangaroo that aresuspected to be hereditary.

With the exception of one report of retinal degenera-tion in a captive Goodfellow’s tree kangaroo (Dendrolagusgoodfellowii) and a description of retinal ganglion celltopography in Doria’s tree kangaroo (Dendrolagus doriana),there are no reports within the veterinary literature detail-ing normal ocular anatomy, pathologic ocular conditions,or the treatment of ocular disease in this species.2,3 We

present a case of bilateral lens luxations and cataracts in acaptive Matshchie’s tree kangaroo that were addressed sur-gically with bilateral intracapsular lens extraction. Becausethe gene pool for this population is small, this problemmay become more prevalent within the captive populationin the United States.

CASE REPORT

A 7-year-old female captive Matschie’s tree kangaroo(Dendrolagus mastchiei) was evaluated because her zoo-keeper and the zoo veterinarian had noted an opacity inthe right eye (OD). The animal could not be handledawake and was immobilized by an intramuscular injectionof a combination of medetomidine (62 mcg/kg; Zoo-Pharm, Laramie, WY, USA), ketamine (3.9 mg/kg; Boeh-ringer-IngelheimVetmedica Inc., St. Joseph, MO, USA),and butorphanol (0.13 mg/kg; Torbugesic, Fort DodgeAnimal Health, Fort Dodge, IA, USA) delivered via aremote delivery system (Telinject 1763 Air Pistol, AguaDulce, CA, USA). The animal was placed in sternalrecumbency for the ophthalmic exam which included dif-fuse illumination (transilluminator), slit-lamp biomicrosco-py (SL-15; Kowa Company, Tokyo, Japan) and indirectfunduscopy (Keeler Vantage Plus; Broomall, PA, USA).The intraocular pressure (IOP) was estimated using appla-nation tonometry (Tono-pen Vet; Reichert Inc., Depew,

© 2014 American College of Veterinary Ophthalmologists

Veterinary Ophthalmology (2015) 18, Supplement 1, 81–85 DOI:10.1111/vop.12207

LENS LUXATION

QUESTIONS?

1

2

Forthis talkwearegoingtodividethingsintoprimaryandsecondaryglaucomas

3

Ithink abouttheeyeasthekitchensink.

Ifyouturnthetaponandthedrainisworkingproperlythenasmuchwatercomingintothesinkgoesout– hencethesinkdoesnotfill.Ifthereisfoodintheplugholethenthewaterdoesnotdrainasexpectedandthesinkbeginstofill.

ThisishowItrytounderstandtheglaucomas

4

Glaucomaisalways anoutflowproblemandnotanoverproductionofaqueousfluid.

5

Listofbreedspredisposedtoprimaryglaucomas:AkitaAlaskanMalamuteBassetHoundBeagleBorderCollieBostonTerrierBouvier desFlandres BrittanySpanielCairnTerrierCardiganWelshCorgiChihuahuaAmericanCockerSpanielDachshundDalmatianDandie Dinmont TerrierEnglishCockerSpanielEnglishSpringerSpanielGermanShepherdGiantSchnauzerGreyhoundIrishSetterItalianGreyhoundLakelandTerrierMalteseMiniaturePinscherMiniatureSchnauzerNorfolkTerrierNorwegianElkhoundNorwichTerrierPoodle-Toy/MiniatureSamoyedScottishTerrierSealyhamTerrierShihTzuSiberianHuskySkyeTerrier

6

Listofbreedspredisposedtoprimaryglaucomas:AkitaAlaskanMalamuteBassetHoundBeagleBorderCollieBostonTerrierBouvier desFlandres BrittanySpanielCairnTerrierCardiganWelshCorgiChihuahuaAmericanCockerSpanielDachshundDalmatianDandie Dinmont TerrierEnglishCockerSpanielEnglishSpringerSpanielGermanShepherdGiantSchnauzerGreyhoundIrishSetterItalianGreyhoundLakelandTerrierMalteseMiniaturePinscherMiniatureSchnauzerNorfolkTerrierNorwegianElkhoundNorwichTerrierPoodle-Toy/MiniatureSamoyedScottishTerrierSealyhamTerrierShihTzuSiberianHuskySkyeTerrier

6

SmoothFoxTerrierTibetanTerrierWelshSpringerSpanielWelshTerrierWestHighlandWhiteTerrierWireFoxTerrier

6

7

Technicallynotaglaucoma butwilladdithereforcompleteness:Postoperativeocularhypertension(highintraocularpressure afterphacoemulsificaiton)

8

- Physicalexaminationmayuncoversomeothersignsofsystemicdiseasemakingsecondaryglaucomaduetouveitismorelikely

- Lookingattheothereyecanuncoversomeothersignsofuveitishencebilateraluveitis,makingsecondaryglaucomaduetouveitismorelikely

- Gonioscopy ofthe‘normaleye’canrevealabnormalappearanceofpectinateligamentsandpotentiallyshowclosureofthedrainageangle,thismaymakeprimaryglaucomamorelikely

- Ocularultrasoundofanyeyethatyoucannotseeinside(duetomarkeddiffusecornealoedema orhyphema forexample)willhelpwithfindingtheunderlyingdiagnosis(neoplasiaorlensluxationforexample)– don’tforgetmostofthetimeyouhavetheother‘normal’eyetocompareto!

- Ifyouaresuspectinganunderlyingsystemicdiseasethenbloodsandimagingcanbehelpfultoo!

9

Iamavoidofusingtopicalbetablockersiscats,dogs<10kgandpatientswithcardiacorpulmonarydisease.IhavealsohadLurcher /Whippetbreedsthathavebeenmorethan10kgwithseverbradycardiaandsystemichypertensioninICUafteradministrationofCosopt postphacoemulsificaiton.Takecareandmonitorpatentsstartingonbetablockersclosely.

Itendtousetheseasalastresortadditiontoatopicalantihypertensiveprotocolratherthanafirstline.

ItisimportanttorememberthatafteraspikeinIOPtherecanbeinflammationinsidetheeyesoIusesystemicortopicalanti-inflammatoriestoo!

10

IOP Curvesarecarriedoutinthefollowingway:- IOPreadingtakenwithaTonoVet everythreehoursfora30hperiodstartingat9amonthefirstmorning(thisissoaswecangettwomorningreadingsin)

- AprotocolissetforeachpatientwhereiftheIOPisoveracertainparameterthenatopicalmediationshouldbegiven

- IfthisoccursthenIOPisrepeatedonehourlater- IOPcurvesareperformedanywherefrommonthlytosixmonthlydependingoneachpatientandtheresultsofthepreviouscurve

Wehavehadpatientsthathavekepttheirremainingeyefor3yearsafterthefirsteyewasremovedbymonitoringthreemonthlywithIOPcurvesandtopicalmedications.Frequentalterationsoftiming,frequencyandtypeoftopicalantihypertensivehavehelpedthesecases.

11

I generallyliketousetopicalratherthansystemicmedicationstoreduceIOPinprimaryglaucoma’s.IworryabouttreatingwithMannitolorsystemiccarbonicanhydraseinhibitorsduetotheirsystemicsideeffectsandpotentialcomplications.

ItisimportanttorememberthatafteraspikeinIOPtherecanbeinflammationinsidetheeyesoIusesystemicortopicalanti-inflammatoriestoo!

12

Ihaveneveryet performedparacentesis forprimaryglaucoma.Ifthepressureisnotrespondingtolatanoprost andisblindIwouldrecommendenucleation.

Idonotoften offersurgicaltherapiesforprimaryglaucomaduetothereportedsuccessratesbeinglowandthattopicalmedicationsareoftenstillrequired.ThissaidIammindfulthatIprobablydonotoffersurgeryuntilverylateinthediseaseprocessandthatperhapsifIdiditsoonermysuccessratesmaybeimproved.IhavefoundthatwithlasertherecanbealotofinflammationinsidetheeyesaftersurgeryandthereforeaspikeinIOP.AlsowithGonioimplants Ihavefoundthattheyblockwithfibrinandneedsomeinterventions.AllthisaddstothecostandIhavefoundIhavetocouncilclientsbeforeembarkingontheseinterventionstoavoiddisappointment.MaybeIamatoonegative!

P.S.Ihavehadgoodexperienceswithlaserandlensluxationpatients

13

Further investigationsareimportanttohelpyoufindanunderlyingcaseforexampletreatinglymphomawillreducetheIOPbyclearingthedrainageangleofneoplasticcells.Ordiagnosisofanintraocularneoplasiaviaultrasoundwillguideyoumoretowardssurgicalintervention.

14

MannitolandPGanalogues willpotentiallyincreaseIOPincasesofsecondaryglaucomawhenuveitisisaplayer.ThisisbecausethebloodaqueousbarrierisalreadyleakyandthenthelargemannitolmoleculeswilldiffuseinandbringwaterwiththemincreasingIOP.WithPGanaloguestheyarepro-inflammatoryhenceexacerbatingtheincreaseinIOP.

Thatsaid,sometimesyourhandmaybeforcediftherearenootheroptionsandtheeyeispainful.

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anes

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ow.

NOTES:

BRAVO COMMITTEE MEMBERS 2017

Chairperson – Tim Knott Tim Graduated with an honours degree in Anatomical Science from Bristol University in 1991, followed by his Veterinary degree in 1995. Tim holds the RCVS certificate in Veterinary Ophthalmology and runs Rowe Referrals, Bristol. Hi is interested in all aspects of mixed practice but has special interests in ophthalmology, exotic animal medicine and surgery and fish disease. As chairperson, Tim overseas the running of the committee and chairs our meetings. Soon to be Chairperson – Ida Gilbert (NEW) Ida graduated from Bristol Veterinary School in 1995. Following two years in mixed practice she decided to commit to her interests in ophthalmology and moved to Eastcott Veterinary hospital in Swindon, where she gained her RCVS Certificate in Veterinary Ophthalmology in 2001. She enjoys all areas of Veterinary Ophthalmology and still works and lives in rural Wiltshire. Ida will be taking over the chair role next year when Tim steps down. Joint Secretary – Natasha Mitchell Natasha graduated from University College Dublin in 1998 with a degree in Veterinary Medicine. She obtained the Royal College of Veterinary Surgeons’ (RCVS) Certificate in Veterinary Ophthalmology in 2004. She later joined the Eye Veterinary Clinic in Herefordshire where she completed an alternative residency programme for the RCVS Diploma in Veterinary Ophthalmology, which she obtained in 2011. She is a Veterinary Council of Ireland recognised specialist in Veterinary Ophthalmology. Natasha runs a referral veterinary ophthalmology service, Eye Vet, in Limerick, Ireland. She assists Negar in her very busy role as secretary, enrolling new members and answering general enquiries. Joint Secretary - Negar Hamzianpour (NEW) Negar graduated from the University of Liverpool in 2011. She developed a passion for veterinary ophthalmology during her general internship at the Royal Veterinary College (2012-2013). After several years in general practice (Goddard Veterinary Group), where she completed a post-graduate certificate in small animal ophthalmology, she returned to referral work to undertake an ophthalmology internship at Willows Veterinary Referrals. Negar will undertake an ECVO residency programme at the Eye Veterinary Clinic (Leominster) in the New Year. As secretary, she is involved with the enrolment of new members and answering general enquiries. Hotel and conference organiser – Helen Appelboam Helen qualified from Royal Veterinary College, London in 2001. Originally from Hampshire but keen to see the world, veterinary work has taken her to South Africa and New Zealand where she gained experience in small animal and equine practice. Her interest in ophthalmology grew after seeing practice with specialist veterinary ophthalmologists in these countries. On returning to the UK, she spent 4 years developing her skills in a small animal and eye referral practice in Bristol and studying for the RCVS Veterinary Ophthalmology Certificate, which she achieved in 2011. She joined Optivet Referrals in 2012. Helen’s job is to research the venues for our conferences each year and oversee the running of the conference itself. International liaison – Michael Ziglar Michael completed his Bachelor of Science degree in 1975 at the University of Guelph. He went on to complete his DVM in 1979 at the Ontario Veterinary College, University of Guelph. From 1979 to 1982 he worked as an associate veterinarian in two different Alberta small-animal clinics. He then returned to Ontario in 1982 and opened Bronte Road Animal Hospital in 1984. In 1993 Michael completed examinations and received the RCVS Certificate in Veterinary Ophthalmology. Michael has been involved with both undergraduate teaching and delivering numerous continuing education presentations across North America. He has also been past President of both the American Society of Veterinary Ophthalmology and Canadian Association of Veterinary Ophthalmology where he is also an Honorary Life Member. This new role of international liaison is to try and promote BrAVO abroad and encourage international contacts. Website and audio-visual – David Nutbrown-Hughes After graduating from Bristol in 1995, David had worked in practices in Worcestershire, Somerset and West Sussex where he built on his interest in ophthalmology, gaining the RCVS Certificate in Veterinary Ophthalmology in 2004. Since June 2012 David has joined the ophthalmology team at Rowe Referrals, Bristol. David runs the BrAVO website and is also involved with setting up the audio-visual facilities at each meeting.

TIM KNOTT

IDA GILBERT

NATASHA MITCHELL

NEGAR HAMZIANPOUR

HELEN APPELBOAM

MICHAEL ZIGLAR

DAVID NUTBROWN-HUGHES

CHARLIE BARTON

 

 

 

 

 

 

BRAVO COMMITTEE MEMBERS 2017

Disease surveillance officer – Charlie Barton (NEW) Charlie graduated from Bristol in 2004, and worked in a variety of mixed, and latterly small animal practices. He gained the RCVS Ophthalmology certificate in 2011 and became an advanced practitioner in Veterinary Ophthalmology in 2013. Whilst working in general practice he started a client communications and compliance software company, Virtual Recall, which he now manages full time as it continues to grow internationally. Unfortunately this means that Charlie does not currently have time to see clinical cases, but he still maintains a strong interest in everything Veterinary based, especially Ophthalmology. Outside of this, Charlie enjoys life in Norfolk with his family including 2 kids and a scrappy Lurcher – Dougal; playing tennis, climbing, running and cycling whenever possible (rarely!). This new role will specifically examine the incidence and prevalence of ocular conditions through-out the UK using BrAVO members as a database.

Scientific programme organiser – Rachael Grundon Rachael graduated from Cambridge and spent many years in mixed general practice before specialising in ophthalmology. She undertook her residency in Melbourne gaining the ANZCVS Fellowship in 2014. She is now working at the Eye Vet Clinic in Herefordshire while completing an ECVO residency.

Scientific programme organiser – Chris Dixon (NEW) Chris graduated from the University of Bristol and spent several years working in first opinion mixed practice in the North Yorkshire Moors and Cumbria. During his time at the University of Bristol Chris was lucky enough to be mentored by Professor Sheila Crispin, and this tuition inspired a persistent interest in ophthalmology. Early in his veterinary career, Chris decided to focus on ophthalmology due to the exciting mixture of microsurgery and medicine, and attained the RCVS postgraduate certificate. In 2010 Chris joined fellow ophthalmologist Gary Lewin, and in 2012 they formed Veterinary Vision, a dedicated ophthalmology referral practice based in Penrith, Cumbria. Chris has presented clinical research at national and international veterinary ophthalmology conferences, and has a particular interest in topographical analysis of the cornea and retinal reattachment surgery.

Scientific programme organiser – Christine Heinrich Christine graduated from Munich Veterinary School in 1994 and immediately afterwards moved to the UK, where she undertook both an Internship and a Residency in Ophthalmology at the Animal Health Trust in Newmarket. Since 2000, Christine has been in private ophthalmic referral practice in the UK and she is both a diplomate of the Royal College of Veterinary Surgeons (Ophthalmology) and of the European College of Veterinary Ophthalmologists. In 2015, Christine took over the Eye Veterinary Clinic in Leominster, a dedicated ophthalmic referral clinic for all species. Despite a busy clinical work-load, Christine has continued to enjoy the teaching of Veterinary Ophthalmology both to pre-and post-graduate veterinary surgeons, including lecturing nationally and internationally and the mentoring of residents under the ECVO residency program. Editor – Mike Rhodes Mike graduated from Edinburgh University in 2004 and spent the next three and half years working in small animal practice in Peterborough and Suffolk. During this time he developed a keen interest in veterinary ophthalmology and completed the RCVS Certificate in Veterinary Ophthalmology in 2008. He then undertook a three-year ECVO residency programme at Willows Referral Service and obtained the European Diploma in Veterinary Ophthalmology in 2013. Mike has just started his own peripatetic referral business within the M40 corridor called Focus Referrals Ltd. Mike’s job is to prepare the meeting proceedings as well as to assist Christine, Rachael and Chris in putting together the scientific programme. Clinical Auditor – Jenny Lambert Jenny works at Bath Referrals and obtained the RCVS Certificate in Veterinary Ophthalmology in 2003. As clinical auditor, Jenny aims to create an ongoing cycle of continuous improvement, by collecting data and comparing current practice with evidence of good practice. Soon to be treasurer – Alistair Oldfield (NEW) Having graduated in 1997 from Bristol University, Alistair joined Woodcroft Veterinary Group in June 2002 after working nearly five years at the PDSA clinic in Manchester. Having attained his RCVS Certificate in Veterinary Ophthalmology, Alistair sees referral ophthalmology cases as well as continuing his work in general small animal practice. Alistair is due to take over the role of treasurer when Rob steps down this year.

RACHAEL GRUNDON

CHRIS DIXON

CHRISTINE HEINRICH

MIKE RHODES

JENNY LAMBERT

ALISTAIR OLDFIELD

RACHAEL GRUNDON

CHRIS DIXON

CHRISTINE HEINRICH

MIKE RHODES

JENNY LAMBERT

ALISTAIR OLDFIELD

RACHAEL GRUNDON

CHRIS DIXON

CHRISTINE HEINRICH

MIKE RHODES

JENNY LAMBERT

ALISTAIR OLDFIELD

RACHAEL GRUNDON

CHRIS DIXON

CHRISTINE HEINRICH

MIKE RHODES

JENNY LAMBERT

ALISTAIR OLDFIELD

TIM KNOTT

IDA GILBERT

NATASHA MITCHELL

NEGAR HAMZIANPOUR

HELEN APPELBOAM

MICHAEL ZIGLAR

DAVID NUTBROWN-HUGHES

CHARLIE BARTON

 

 

PROGRAMME FRIDAY 3rd NOVEMBER MASTERCLASSES

Friday morning 09.30-12.30 (with flexible 30min comfort/coffee break midway):

1) Pathology (Emma Scurrell)

2) Photography (Tim Knott and Chris Dixon)

3) Anaesthesia (Karen Walsh and Carl Bradbrook)

4) Ocular surgery wet lab (Rob Lowe, Heidi Featherstone, Rachael Grundon)

12.30-13.30 LUNCH, travel between Marriott and Versalius clinical training suite on

Southwell Street Friday afternoon 14.00-17.00 (with flexible 30min comfort/coffee break midway):

1) Pathology (Emma Scurrell)

2) Photography (Tim Knott and Chris Dixon)

3) Anaesthesia (Karen Walsh and Carl Bradbrook)

4) Ocular surgery wet lab (Rob Lowe, Heidi Featherstone, Rachael Grundon)