HYPERMETROPIA (farsighted) By, Saurabh D. Patel

Topics of DisscussionEtiologyClinical typesClinical presentationDiagnosisManagementComplication

DefinationHypermetropia ( long sightedness )

is a refractive state of eye where in parellel rays of light coming from infinity are focus behind the retina with accomodation being at rest

EtiologyAxial hypermetropia – 1 mm shortening - 3D of hyperopia

Curvature hypermetropia – flat cornea

Index hypermeropia – old age & DM on tretment

Positional hypermetropia – Dislocation of lens

Absence of crystalline lens - Aphakia

Loss of accomodation – d/t age & medication

Clinical typesSimple hypermetropia – axial or curvatural type

Pathological hypermetropia – Maldevelopment of eye

- k & lens changes

- chorioretinal & orbital

inflamation / neoplasma

Functional hypermetropia – 3rd nerve palsy / internal

ophthalmoplegia

PATHOLOGICAL CAUSESOF HYPEROPIA

1 mm = 3D

RETINAL FLUID

DISLOCATED LENS

RETINAL DETACHMENT CHOROIDAL TUMOR

Components of hypermetropiaTotal hypermetropia

Latent hypermetropia – corrected by inherent tone of

cilliary muscle

Manifest hypermetropia – Facultative hypermetropia ( corrected by accommodation)

- Absolute hypermetropia

(does not corrected by

accommodation)

Normal Age VariationAt birth - 2 to 3 diopter of hypermetropiaAt adolesence - it becomes emmetropicB/C in youth – cortex refractive index is less

than that of nucleus – formation of

combination of a central lens surrounded

by two menisci - refractive power

increase

AgeThe mean refractive error is +2.00D in

newborns

The mean refractive error is +1.00 to +0.50D in children at age 6

The mean refractive error is plano in children at age 10

The mean refractive error is skewed toward myopia in children after age 10

Compensating AccommodationFactors

Fatigue – general and ocular Due to continuous focusing of images in and out on

the retinaIllness (e.g., cold, fever)Mental state (e.g., stress)AlcoholDrugs and medications (e.g., antihistamines)

Antihistamines may relax accommodation and dilate the pupils

Clinical featuresSymtoms-AsymptomaticAsthenopic symtomsDefective vision with asthenopic symoptomDefective vision onlyThe effect of ageing on visionIntermittent sudden blurring of vision

SIGNS

Size of eye ball – smallCornea - smallerA/C - shallow & narrow angle Pupil

Enables accommodation and increased depth of focus

EsophoriaInward deviation of the eyesWith accommodation, eyes tend to converge

Visual acuity – depend upon degree of hypermetropia

& power of accomodation -Decreased visual acuities at distance and near, especially the latter

Fundus examination :

retina- whole may shine due to greater brillince of

light reflection(Shot silk appearance)

Optic disc - small , more vascular with ill defined

margins resembles optic neuritis (pseudopapillitis)

Diagnosis of hypermetropia (1) Patients history - watering of eye - eyeache / frontal headache - actual / suspected crossing of eyes - difficulty with clarity / comfortability - presbyopic pt c/o difficulty in near vision - family history

2) Occular examination a) Visual acuity - In young pt - In presbyopic pt - In older age - In pt with never corrected high deree of

hyperopia

b) Refraction# retinoscopy – useful in children ,

accomodative esotropia, latent hyperopia - atropine has max. cycloplagia# Autorefraction- validity & reliability lower

c)Occular motility , binocular vision & accomodation- anomalies in any of them detected by - cover uncover test- near point of convergence- accomodative amplitude

(d) Occular health assurance & systemic heath screening- colour vision - pupillary response- confrontation visual fied test- IOP- occular media & post. Segment evalution

Management of hypermetropia(1) Basis of treatment – depends on

following - magnitude of hypermetropia - presence of astigmatism / anisoconia - patient ‘ age - presence of associated esotropia /

amblyopia - status of accomodation & convergence - demands placed on the visual symtoms

(2) Available treatmentA) Optical correction-spectacles & contact lens

most wildly used - Plus power / spherocylindrical lens prescribed - absolute hyperopia to accept nearly full

correction - young patient with accomodative esotropia & hyperopia require short period of adaptation to tolerate full correction

NORMAL VISION

UNCORRECTEDHYPEROPIA

LENS CORRECTEDHYPEROPIA

Contact lens beneficial in case of - resist to wear spectacles

- improve cosmosis - reduce aniseikonia & anisophoria in persons

with anisometropia - accomodative esotropia beneficial - Unilateral high hypermetropia

(3)Management strategies hyperopic correction # Older children & pre – presbyopic

adults (10 -40 yrs)Low degree of hypermetropia – optical

correction with foggingHypermetropia of moderate degree with /

without associated astigmatism – optical correction with fogging after cycloplegic retinoscopy

Uncorrected hypermetropia lead to near vision problem in early age (30 to 35 yr) as accomodation reserve approaches to presbyopia

Neeeds subjective correction after cycloplegic retinoscopy & require higher near addition than age

Presbyopic correction depends on - patients age - patient ‘ s

job - habit of

patientUnilateral high hypermetropia > 3 D then

contact lens advice> 2.5 D difference in both eyes then

undercorrection is given to eye having more hypermetropia

In high hypermetropia if not accepting high / strongest lens

- in that case it is well to

undercorrect at first then strengthen the lens at interval of few months ( in which weaker lens for distant & full correction for near is given )

-untill the full correction is

comfertably borne

# Younger children (birth to 10 yrs of age)Treatment not require in case of –

Treatment needed in case of – binocular anomalies - decrease visual

acuity - learning

difficulties

< 5 yrs of age - >3 D of hyperopia - early optical correction on basis of full atropinized retinoscopy with other intervention like occlusion / active vision therapy if require

& follow up periodically

Partial hyperopic correction in infants given b/c that does not interfere with emmetropization of infants

Concurrent amblyopia – patching & active vision therapy & full time spectacle wear

B/L high hyperopia – if uncorrected may lead to isometropic amblyopia without esotropia -

- full correctionn require & careful follow up made as previously nonexisting esotropia may present after correction

Occlusion therapy is given in which 6 hrly alternate use of both eyes advice & initial follow up after 15 days to 1 month

Small children always prescribe plastic frame & plastic glasses with full frame & 3 monthly follow up require

# Presbyopic patient - optical correction to distant correction with

near addition# Pathological hyperopia- underlying cause is chief concern – limited

to need to correct hyperopia in best manner

possible - reffer to eye care provider for special

services

(d) Refractive surgeryAutomated lameller keratoplastyHolmium – YAG laser thermal keratoplastyExcimer laserSpiral hexagonal keratotomyConductive keratoplasty

The basic idea is to reshape the cornea using the laser to remove a very thin layer. The reshaped cornea allows the refraction of the eye to be corrected.

LASIK®LASIK stands for Laser-Assisted In situ Keratomileusis. This is the most popular form of laser eye surgery. The laser is used to lift and remove a very thin layer of the cornea. The shape of the cornea is altered to be more curved, so that the light rays can be focused further forward, and on to the retina.

Epi-LASIKSimilar to LASEK, Epi-LASIK is a newer type

of refractive surgery in which an epithelial flap is created with a super-fine blade, instead of an alcohol solution. With Epi-LASIK, the chance of the cells becoming too unstable to be replaced is reduced.

This hyperopia treatment is suitable for people with thin corneas as well as those who have a relatively high degree of farsightedness.

PRK®PRK stands for Photo-Refractive Keratectomy. It is an older surgical operation, that has mostly been replaced by newer techniques.

LASEK®LASEK stands for LAser Sub-Epithelial Keratomileusis. It is an improved form of PRK with some similarities to LASIK. Most of the outer layer of the cornea (the epithelium) is left intact. The LASEK procedure tends to be more painful, and discomfort can last longer than with LASIK.

HYPEROPIC -LASIK

Conductive keratoplasty The CK radio waves , guided by rinse – away

dye - it change the shape of the cornea by shrinking targeted areas of collagen in the eye.

  Quick (about 3 minutes per eye) and painless

& both eyes will be treated the same day.

Do not have side effects such as dry eyes, “halos” and light sensitivity

Also used to correct presbyopia - reduces dependence on reading glasses

(b) Vision therapyEffective in accomodative & binocular

dysfunction resulting from hyperopia

(c) Modifications of patient ‘ s habit & environment - improving light / reduces glare - using better quality of printed material - decreasing visual demands - ergonomic condition at computer terminal

(4) Patient education - Avoid stress or eye strain

- Use appropriate lens - Use good light at work - Avoid prolong period of short distant approach - Maintain proper diet

(5)Prognosis & follow upPhysiological hyperopia - not progressiveChildren with hyperopia – 3 to 6 monthly follow upFor adults (asymtometic) 1 to 2 yr follow upFrequent follow up require in –

ComplicationsRecurrent stye , blepharitis or chalazion

Accomodative convergent squint

Amblyopia

Primary narrow angle glaucoma

Thank you