Accommodative IOL’s

Dr. H. Razmjoo

Isfahan University of Medical Sciences

Achieving the Desired Results in modern cataract surgery: Astigmatism Control

Aspheric Optics

Accurate Biometry

Appropriate Formulas

Adjusting the Outcome

Accommodation

Presbyopia : Solutions?

Sclera?/Cornea

Presbyopic LASIK Corneal Inlays

Lens Multifocal IOL

•Phakic / pseudophakic Accommodative IOL

Consider this issues in evaluating presbyopic

Surgery:Measuring accommodation

True versus Pseudo-Accommodation

Reading ease, speed

Accommodative reserve

Quality of vision - HOAs

True vs Pseudo-accommodationPseudo-

accommodation

- First devices available- IOLs

Refractive – ReZoomDiffractive – ReSTOR

Associated with loss of contrast

sensitivity

True Accommodation

- Transient and rapidly reversible change in optical power of the eye- Generally requires IOL change of shape or position

Not associated with loss of contrast sensitivity

Present IOLs – (FDA)

Monofocal

Pseudoaccommodative Multifocal

• ReSTOR• ReZoom

Accommodative Crystalens

Monofocal IOLs:Excellent visual acuityBest contrast sensitivityNeed for some glassesMonovision

Multifocals: (ReStor / ReZoom)

Good for some… Few years experience Excellent visual acuity Decreased contrast sensitivity

Accommodative:Crystalens

Excellent quality of vision Minimal contrast loss Very poor true accommodation

1-1.5D PCO Future ???

Only 26% spectacle free in some studies

Future accomodating IOL’s

Based on accommodation theories Exact method controversial

Helmhotz’s theory

Ciliary M. contraction Decreased zonular tension

Thicker lens Bag more lax

More PLUS power

Accommodative IOLs

Future of refractive surgeryFDA approved lens has limited

accommodationSmall incision IOLTruly accommodation will be available

when : Right IOL concept / design Maintained long term flexibility of

capsule

Accommodative Models

Lens “filling” Deformable IOL

Single optic

Dual optic

Single optic IOL Hinged haptics

Forward movement > effective power of IOL

Poor accommodation Need 1.5 mm axial move to achieve 2 D ofaccommodation

Dual optic IOL Positive lens anterior / negative lens

posterior

Lenses connected with spring like pieces

Accommodation through ciliary body contraction induced separation of lenses

Large area required

Sarfarazi IOL (B&L)

Dual optic IOL Advantage over single optic

• More accommodation• Less IOL movement required• No glare or contrast issues

Inter-lenticular opacities ?

Accommodation

Available IOLs:

Single optic:Crystalens

Only FDA approved

The capsulorhexis must always be larger than the optic of the IOL, i.e. a capsulorhexis of 6 mm must be selected for an IOL optic of 5 mm. The anterior capsular bag must be placed outside the optic.

When the lens is placed in the capsular bag, it must be pushed backward until there is complete contact with the posterior capsular bag.

At this stage of the surgery, the IOL should not move forward at all; which may cause Z syn.

The IOL must be rotated until it fits exactly.

Then the cortex and the viscoelastic substance behind the IOL optic must be carefully removed.

Finally, the IOL must be pressed completely back onto the posterior capsular bag and may not move forward.

no accommodate for 3 to 5 days

The polyimide material of the haptics causes the IOL to grow firmly together with the capsular bag by fibrosis. At this stage it is important that the patient does not accommodate during the first 3-5 days after implantation.

Atropine

To avoid premature accommodation, the pupil is dilated after surgery with a single dose of atropine and it takes 3-5 days for this accommodation blockade to abate.

Zsyndrome

Indication:This IOL would be appropriate

for all patients.

The FDA approved Eyeonics Inc.’s accommodating IOL, Crystalens AT-45, in November 2003.

Bausch & Lomb acquired Crystalens in 2008 and introduced a newer model called Crystalens HD in 2008.

Crystalens is the only FDA-approved accommodating IOL currently on the market

Studies and Peer Reviews:

In a September 2004 FDA trial involving 325 patients:

100% could see at intermediate distances (24" to 30") without glasses; the distance for most of life's activities

98.4% could see well enough to read the newspaper and the phone book without glasses.

Some patients did require glasses for some tasks after implantation of the crystalens

At this time, there is no long-term, well-designed clinical trials to support the accommodating technology of the Crystalens IOL.

Single optic: 1 CU (Human Optics)

4 flexible haptics for axial movement

Single optic:BioConfold 43 E (Morcher)

Ring haptics for optic movement

Single optic:

Opal (B&L)

Currently in clinical trials

Single optic:

Tetraflex (Lenstec)Depends on axial move

Single optic:

Fluid vision (Power Vision)

Dynamic Optic with Fixed Haptics

Up to 10 D accommodation

Accommodation driven hydraulic lens shape change

NON-ACCOMMODATED

ACCOMMODATED

Single optic:

Flex optic (AMO) Conforms the capsular

bag Changes optic

curvature No axial movement In trial

“Single optic”:

NuLens (Nulens) Flexible polymer between 2 rigid plate,

one with an opening Polymer bulges = more positive lens 30 - 50 D of accommodation theoritically

NuLens

Dual optic:

Synchony ( Visiogen) Dual optic(+ anterior & - posterior) / single

piece “Spring like haptics” Up to 2.5 acc.

Synchony

Bag filling:

Smart IOL (Medennium)

Bag filling Ciliary muscle resumes lens shape change

control - Pliable for accommodation Thin rod that > to desired shape with body

temperature In trial

Bag filling:

Accommodating Injectable Lens

(AMO)

Liquilens (Vision Solutions)

2 fluids with different refractive indexes in center of lens in single optic

Looking down mixes fluids creating a more positive lens

Power changes with the position of the eye

Light adjustable IOL (Calhorn Vision)

Residual refractive error post op laser “adjustment”

Multifocal post op “adjustment” possible ???

Conclusions : Future

Acc. IOL’s should:- Be the hope for the future

- Have a physiologic concept

- Have few optical side effect

Hope for:- Aspheric optics

- Adjustability

- Toricity

- Control of lens epithelial cells

Criticisms: The main concern with

accommodating IOLs is that there are no long-term, large-scale studies involving its use in patients.

potential complications include capsular bag contraction and posterior capsule opacification.

It is more difficult to implant an accommodating IOL (due to the attachment of hinges)

Accommodating IOLs are expensive.

Good candidates:patients over 50 with cataract

problems and no serious eye diseases

The patient must have functional ciliary muscles or zonules

patients must include ophthalmologic exercises such as puzzles and word games as a part of their daily regimen in order to tone up their ciliary muscles and attain the maximum benefit from the accommodating lenses.

These exercises should be done consistently for 3–6 months

Future accomodating IOL’s

Based on accommodation theories Exact method controversial

Helmhotz’s theory

Ciliary M. contraction Decreased zonular tension

Thicker lens Bag more lax

More PLUS power

Thank you for your attention