Retinal dystrophies can be divided into four groups: generalized photoreceptor dystrophies, macular dystrophies, generalized choroidal dystrophies, and hereditary vitreoretinopathies. Retinitis pigmentosa is the most common form of generalized photoreceptor dystrophy and is characterized by progressive vision loss starting with night blindness and constricting visual fields. It can be inherited in autosomal dominant, recessive or X-linked patterns. Other forms of generalized photoreceptor dystrophy discussed include atypical RP, cone dystrophy, and Bietti crystalline choreoretinal dystrophy.

1. Presenter
Dr. Farhad Uddin Ahmed
MS Phase B student
NIO&H

2. Chairman
Professor Dipak Kumar Nag
Dpt. of Vitreo-retina
NIO&H
Moderator
Asst. prof. Dr Koushik Chowdhury
Dpt. of Vitreo-retina
NIO&H

3. Introduction
Retinal dystrophies can be subdivided into four groups-
1. Generalized photoreceptor dystrophies
2. Macular dystrophies
3. Generalized choroidal dystrophies
4. Hereditary vitreo-retinopathies

4. Generalized Photoreceptor dystrophies:
• Retinitis pigmentosa
• Atypical RP
• Cone dystrophy
• Bietti crystalline choreoretinal dystrophy
• Alport syndrome
• Familial benign fleck retina
• Congenital stationary night blindness

5. Macular dystrophies:
• Stargardt Dystrophy
• Best vitelliform macular dystrophy
• Pattern dystrophy of the retinal pigmented epithelium
• North Carolina macular dystrophy
• Sorsby pseudoinflammatory dystrophy
• Concentric annular macular dystrophy
• Familial ILM Dystrophy
Generalized choroidal dystrophies:
• Choroideremia
• Gyrate atrophy
• Progressive Bifocal Chorioretinal Atrophy

6. Hereditary Vitreoretinopathies-
• Juvenile X linked Retinoschisis
• Stickler syndrome
• Wagner Syndrome
• Familial exudative vitreo-retinopathy
• Enhanched S-cone syndrome and Goldmann-Favre syndrome
• Snowflake vitreoretinal degeneration
• Autosomal dominant neovascular inflammatory vitreo-retinopathy
• Autosomal dominant vitreoretinochoroidopathy
• Kneist Dysplasia

7. Generalized Photoreceptor dystrophies

8. Retinitis Pigmentosa
• Pigmentary retinal dystrophy
• Clinically and genetically diverse group of
inherited diffuse retinal degenerative disease
• Predominantly affecting the rod photoreceptors
initially, with later degeneration of the cones.
(rod-cone dystrophy)
• Most common hereditary retinal dystrophy.
• Incidence: -
 World wide- 1: 5000
 Age- Appears in childhood, slowly causing
blindness in advanced middle age.
 Race- Equal in all races.
 Sex- Males > Females 3:2
 Laterality- Invariably Bilateral disease.

9. Cont.
Inheritance:
1. Sporadic- 60%- Most common
2. Inherited- 40%
a) Autosomal Dominant- 43% ;Best Prognosis
b) Autosomal Recessive- 20%
c) X-linked – uncommon 10%; Worst Prognosis
d) Uncertain family history 6-8%
Genetic Basis of Disease:
1) Rhodopsin Mutation (Chr 3q21)- at least 100 mutations in
Rhodopsin gene can RP.
2) RDS protein Mutation (Chr 6p12)- Generally associated with
Autosomal Dominant disease.
3) Abnormal p mRNA splicing- due to faulty mRNA splicing.
4) Others- Mutation in RP GTP ase regulator, Mutation in ABCR
gene.

10. Retinitis Pigmentosa
Symptoms of RP-
1. Nyctalopia: Characteristic feature that
 Appears before the appearance of fundus changes.
 Occurs due to degeneration of the rods.
 Masof & Finkestein classified RP as-
1. Type 1 RP- Childhood onset night blindness. Early loss of rod sensitivity compared to cone
sensitivity. autosomal recessive.
2. Type 2 RP- Adult onset night blindness. Combined loss of rod and cone sensitivity. autosomal
dominant disease
2. Dark Adaptation difficulties- increased due to increased light threshold to
peripheral retina.
3. Visual field loss- Progressive loss of peripheral vision, ultimately leading to
tunnel vision in advanced disease.
4. Others- Photopsia, diminished contrast sensitivity.
5. Visual acuity remains normal till late stage disease.

11. Theories of Retinitis
Pigmentosa:
1. Vascular theory-
a) Sclerosis of choroid and
choriocapillaris.
b) Sclerosis of retinal vessels.
2. Pigmentary changes-
Changes in neuroepithelium and
pigmentary epithelium.
3. Abiotrophic- Early
degeneration and loss of function
of cells.
4. Premature seniling and death
of cells of specified tissue.
Progression of RP

12. Fundus Finding of RP-
1) Bony spicules: due to migration of pigments in
the retina from disintegration of RPE cells with
accumulation in the interstitial space surrounding
retinal vessels. changes are equatorial region
first, and spread anteriorly and posteriorly.
Gradual increase in density.
2) Gliotic Optic nerve head: It starts with a variable
waxy disc pallor. In later in leads to consecutive
optic atrophy.
3) Vascular changes: gross arteriolar narrowing.
4) General retinal changes: Generalized granularity
of the fundus. Pigment clumps or bone spicule
appearing pigment deposits. A generalized
mottling or moth eaten pattern of the RPE.
5) Macular change: Loss of foveal reflex.
6) Vitreous change: Fine dust like particles which
progress into vitreous condensation and collapse
with progressing disease.

13. Investigations:
1. ERG- Reduced scotopic rod and combined
responses. Rod B wave amplitudes are
reduced in the earliest stage the disease.
2. EOG- Subnormal, with absence of the light
rise.
3. Visual fields
4. OCT
5. Fundus Autofluorescence- Lack of
signals on FAF (due to RPE atrophy).
6. Genetic analysis- To identify the
particular mutations, to facilitate genetic
counseling and for research purpose.

14. Treatment of RP-
1) No definitive treatment is yet available.
2) Regular follow up to detect and treat , treatable vision threatening
complications (PSC, CME)
3) Smoking to be avoided, as it aggravates the disease.
4) High dose Vit A supplementation
5) Cataract surgery for PSC is beneficial for vision.
6) Low vision aids- Optical aids, Non optical device
7) Valproate/Phenytoin- Is used as a retino-protective drug.
8) Potential retinotoxic medications should be avoided or used with caution.
9) CMO in RP responds to oral Acetazolamide
10) Retinal prosthesis/Implants- Artificial implants like Bionic eye/Argus 2
implant proof beneficial.

15. Atypical RP
Heterogeneous disorders clinically having features in common with typical pigmentary
retinal dystrophy.
Atypical RP with systemic disorder [Syndromic association]-
1) Usher Syndrome-
• Autosomal Recessive.
• About 5% of all cases of profound deafness in children and half of all the cases of
combined deafness and blindness.
• Three major types-
a) Type 1 (75%)- Congenital sensorineural deafness and severe RP
b) Type 2 (23%)- Moderate to severe hearing loss. Onset of night blindness
occurs during the late teens or early twenties. Peripheral vision loss is
ongoing, but central vision is usually retained into adulthood. Visual
problems associated with Usher syndrome type 2 tend to progress more
slowly than those associated with type 1.
c) Type 3 (2%)- Usher syndrome type 3 is characterized by later onset hearing
loss, vestibular dysfunction and RP that can present between the second
and fourth decade of life.
• Fundus findings- Salt and pepper retinal pigmentation and optic atrophy

16. 2) Kearns-Sayre syndrome-
 Mitochondrial inheritance.
 Chronic progressive external ophthalmoplegia with
ptosis, associated with other systemic problems.
 Fundus findings- salt-pepper appearance most
striking at the macula, with less typical presentation
of RP.
3) Bassen-Kornzweig syndrome-
 Autosomal recessive.
 Dysfunction in absorption of fat and fat soluble
vitamins(A,D,E,K).
 Failure to thrive in infancy and development of
severe spino- cerebellar ataxia
 Blood film shows thorny red cells (acanthocytosis).
 Fundus finding- Scattered white dots followed by
RP-like changes developing towards the end of the
first decade, associated with ptosis,
ophthalmoplegia, strabismus and nystagmus.
 Vit supplementation and low fat diet are
implemented.

17. 4) Refsum disease-
 Autosomal recessive.
 Consists of genetically and clinically distinct
infantile and adult forms.
 Phytanic acid accumulates throughout the body
with substantial and varied skin causing ichthyosis,
neurological and visceral features.
 Retinal changes may be similar to RP or salt-pepper
appearance associated with cataract and optic
atrophy.
5) Bardet-Biedel syndrome-
 Genetically heterogenous. Associated polydactyl
and mental handicap.
 Fundus picture- Bull’s eye maculopathy due to
cone-rod dystrophy and less frequently typical RP,
RP sine pigmento, retinitis puncta albescens.

18. Retinitis Punctata Albescens
 AR or AD inheritance
 Scattered whitish-yellow spots, most numerous at the equator,
usually sparing the macula and associated with arteriolar
attenuation.
 Similar to spots in Fundus albipunctatus.
 By the fifth and sixth decades there may be retinal pigment
atrophy in the midperiphery
 Eventually progresses to geographic atrophy of the macular
RPE
 Visual field becomes more constricted.
 Symptoms- Nyctalopia, Progressive visual field loss.
 Prognosis is poor. ERG reduced.
 Treatment- No definitive treatment. Low vision aids are useful.

19. Bietti Crystalline Corneo-retinal dystrophy
 Inheritance- AR
 Deposition of crystals in the retina and superficial
peripheral cornea, it is associated with systemic lipid
metabolism error.
 More common in East Asian population.
 Presentation- Young adults with slowly progressing
visual loss.
Signs-
1. Superficial peripheral corneal crystals.
2. Numerous fine yellow-white crystals scattered across the
fundus.
3. Diffuse atrophy of the choriocapillaris subsequently
develops, with decrease in size and number of crystals.
4. Gradual confluence and expansion of the atrophic areas
into periphery, leading to diffuse chorio-retinal atrophy
in end stage disease.

20.  Investigation-
 Visual field shows constriction
 OCT demonstrates the crystalline
deposits and macular changes.
 ERG is subnormal.
 FA in moderate disease shows
characteristic large hypofluorescent
corresponding to choriocapillaris loss,
with intact overlying retinal vessels;
the patches become confluent over
time.

21. Cone Dystrophy
 Cone-rod dystrophies with cones being affected
earlier and more severely than the rods.
 Inheritance- Sporadic (most common), AD, XLR.
 Presentation- In early adulthood, with impairment
of central vision rather than the nyctalopia of rod-
cone dystrophy.
 Symptoms- Gradual bilateral impairment of central
and color vision.
 Signs-
• Macula may virtually be normal or show non- specific
central pigmentary changes or atrophy.
• Bull’s eye maculopathy is classically found, but not
universal.
• Progressive RPE atrophy at the macula with eventual
geographic atrophy.

22. Cont.
 Investigations-
1) FAF-Shows annular pattern concentric with the fovea.
2) ERG- Photopic responses are sub normal or non
recordable and flicker fusion frequency is reduced.
3) EOG- Normal or subnormal.
4) Color vision- Severe deuteron-tritan defect.
5) FA- Shows a round hyperfluorescent window defect with
hypo fluorescent center.
 Prognosis- Poor, with visual acuity of 6/60 or worse.
 Treatment- No specific treatment. Lutein, Zeaxanthin
and omega 3 fatty acids have been prescribed in some
cases have shown good outcome.

23. Leber Congenital Amaurosis
 Severe rod-cone dystrophy
 Commonest genetically defined visual impairment
 AR, genetically heterogeneous, 23 gene loci identified.
 Systemic association- Mental handicap, Deafness,
Epilepsy, CNS anomaly, Renal anomaly, Skeletal
malformation and Endocrine dysfunction.
Presentation- Blindness at birth or early infancy,
associated with roving eye movements or nystagmus
and photo aversion.
Signs-
1. Absent or diminished pupillary light reflex.
2. The fundi may be normal in early life apart from
mild arteriolar narrowing.
3. Initially mild peripheral pigmentary retinopathy,
salt- pepper changes and less frequently yellow
flecks.
4. Severe macular pigmentation or coloboma like
atrophy.
5. Pigmentary retinopathy, optic atrophy and
severe arteriolar narrowing in later childhood.

24. Cont.
6. Oculodigital syndrome-constant rubbing of the eyes may cause
orbital fat atrophy with enophthalmos and subsequent keratoconus
or keratoglobus.
7. Other associations include strabismus, hypermetropia and
cataract.
8. First sign noticed by parents is nystagmus.
 ERG is usually non-recordable even in early cases with normal-
appearing fundi.
 Prognosis- Poor.
 Treatment- No definite treatment. Gene therapy is the only hope.

25. Alport Syndrome
 X-linked Recessive.
 Mutation in major gene of type 4 collagen,
major basement membrane component.
 It is characterized by chronic renal failure and
sensorineural deafness.
 Fundus: Scattered yellowish punctate flecks in
perimacular area, larger peripheral flecks, some
of which may become confluent.
 ERG is normal and visual prognosis is excellent.
 Anterior lenticonus and posterior
polymorphous corneal dystrophy may be
present.

26. Familial Benign Fleck Retina
 Rare Autosomal Recessive disorder.
 Asymptomatic
 Incidental finding
 Fundus- Yellow-white polymorphous
lesion spare the fovea and extend to
the far-periphery.
 The flecks are made of lipofuscin,
show auto-fluorescence
 ERG is normal.
 Prognosis excellent.

27. Congenital Stationary Night Blindness
 Group of disorders characterized by infantile-onset nyctalopia but non
progressive retinal dysfunction.
 With Normal fundus appearance-
1. Type 1 (complete)- complete absence of rod pathway function and
essentially normal cone function clinically and on ERG.
2. Type 2(incomplete)- Impairment of both rods and cones function.
3. Inheritance- AD form is usually associated with normal visual acuity, AR, XLR
patients have poor vision with nystagmus, often significant myopia.

28. Cont.
 With an Abnormal Fundus Appearance-
1) Oguchi disease-
 Autosomal Recessive inheritance.
 The fundus has an unusual golden-yellow color
in the light adapted state which becomes
normal after prolonged DA. (Mizuo or Mizuo-
Nakamura phenomenon).
 Rod function is absent after 30 minutes of DA
but recovers to a near normal level after a long
period of DA.

29. Cont.
2) Fundus Albipunctatus-
 Inheritance- AR or AD.
 Same entity as retinitis punctata albescens
 There are multiple tiny white dots that are very
regularly spaced, involve the posterior pole, spare
the fovea, and extend into the mid-periphery.
 In contrast to Retinitis Punctata Albescens, the
retinal blood vessels, optic disc, peripheral fields
and visual acuity remain normal.
 Prognosis-Excellent.
 FA- Shows mottled hyperfluroscence, indicating
depigmentation of RPE.
 ERG- Reduced.

30. Macular dystrophies
 “Macular dystrophy” has been used to refer to a group of
heritable disorders that cause ophthalmoscopically visible
abnormalities in the portion of the retina bounded by the
temporal vascular arcades.
 Inherited in a Mendelian fashion
 The associated pathology is limited to the eye
 Lesions are biomicroscopically visible in the macula when
symptoms first occur (and in some cases, before symptoms
occur)

31. STARGART DISEASE
 Fundus Flavimaticus and Stargardt’s are the
variant of the same disease.
 Most common Macular dystrophy.
 Accumulation of Lipofuscin within the RPE.
 Types:
1. STGD1- Autosomal Recessive. Most common type.
Mutation in gene ABCA4.
2. STGD3- Autosomal Dominant.
3. STGD4- Autosomal Dominant.
 Presentation in Childhood/Adolescence.
 Prognosis for maculopathy is poor.
 Visual acuity is usually 6/12 to 6/60.
 Patients with flecks in early stages have
relatively good prognosis.

32. Continue...
 SYMPTOMS:
• Slowly progressive
• Gradual impairment of central vision(6/12 to 6/60).
• Reduced color vision & dark adaptation.
 SIGN:
• Non specific motling
• Perifoveal flecks .
• Oval area of atrophy of RPE in the macula, typically
described as “snail slime” or “beaten bronze”
appearance.
• Subsequently Geographic atrophy
• More flecks appear beyond the macula but do not
extend into the periphery.
• The disk and blood vessels remain normal

33. Investigation
 FA-
• Dark choroid .
• Macula-mixed hyper & hypofluorescence.
• Fresh flecks- early hypofluorescence & late
hyperfluorescence
• Old flecks- RPE window defect
 FAF-
• Hyperautofluorescent flecks &
• Peripapillary And macular
hypoautofluorescence
VF-
• Cetral scotoma

34. Cont.
 OCT- Foveal thickness & foveal atrophy
 ERG: Photopic is normal to sub normal ,
scotopic may be normal.
 EOG: Commonly subnormal, especially in
advanced cases.
 ICGA shows fresh hypofluroscent spots.

35. Management
• No specific treatment, condition remains incurable .
• Isotretinoin or Vit A is not recommended.
• Low vision aids can be useful.
• General measurement : protection from excessive high energy light exposure by
UV blocking sunglass.
• Gene therapy.

36. BEST DISEASE/Juvenile onset vitelliform dystrophy
• Best macular dystrophy (BMD) or
Best vitelliform macular dystrophy is
an autosomal dominant condition.
• The first family with this dystrophy
was described by Friedrich Best in
1905.
• It is one of the most common
Mendelian macular dystrophies
• Prognosis is usually good until
middle age, after which VA declines
in one or both eyes.

37. Genetics
• The causative gene is VMD2 (on choromosome11q13)
encoding bestrophin.
• The protein has been localized to the plasma membrane of
RPE and work as transmembrane ion channel. Abnormal
chloride conductance might be the initiator of the disease
process.
Histological Features -
• Increased RPE lipofuscin.
• Loss of photoreceptors
• Sub-RPE drusenoid material accumulation in cells and
material in the subretinal space.

38. Clinical features
• Previtelliform stage. This is evident as a small, round
yellowish dot at the site of foveola.Subnormal EOG.
• Vitelliform stage can lead to appearance of cyst with
fluid level or sometimes clear space in center with
the material situated all round. Sub- retinal
neovascularization (CNVM) is complication.
• Pseudohypopyon may occur when part of the lesion
regresses often at puberty.
• Vitelliruptive: the lesion breaks up and visual acuity
drops
• Atrophic stage can be represented by area of RPE
atrophy or sometimes disciform scar if complicated
by CNVM

39. Investigation:
1. FAF- hyperautoflurorescent, in atrophic stages hypoautofluorescent
2. OCT macula- materials beneath, above & within RPE
3. FFA- central hypofluorescence at vitelliform stage and hyperfluorescence
later due to atrophic RPE .
4. EOG- Typically EOG is affected early in the stage of the disease.
5. ERG- completely normal
Management:
• Treatment for BEST1 disease consists primarily recognizing choroidal
neovascularization and treatment with anti-VEGF therapy.
• Even in the absence of CNV, subretinal hemorrhage can occur in Best disease
following relatively modest head or eye trauma.
• Protective eyewear is recommended for all sports

40. PATTERN DYSTROPHY
• Pigmented pattern dystrophy was originally described with
black pigmentation in the macular area.
• Subsequent reports included yellow, gold and gray
subretinal deposits as well.
GENETICS-
• Mutations in a single gene, PRPH2.
• The condition is autosomal dominant in transmission.
• Peripherin and RDS gene mutations have been identified in
these families.

41. Cont.
Butterfly-shaped:
Foveal yellow and melanin pigmentation,
commonly in a spoke-like or butterfly wing-like
conformation. Drusen- or Stargardt-like flecks
may be associated with any pattern dystrophy .
FA
Shows central and radiating hypofluorescence
with surrounding hyperfluorescence

42. Cont.
Multifocal pattern dystrophy:
• Simulating fundus flavimaculatus:
• Multiple, widely scattered, irregular
yellow lesions;
• They may be similar to those seen in
fundus flavimaculatus .
FA -
Shows hyperfluorescence of the flecks; the
choroid is not dark

43. Cont.
Macroreticular (spider-shaped):
• Initially pigment granules are seen at
the fovea
• Reticular pigmentation develops that
spreads to the periphery
• Fluorescein angiography reveals the
patterns more clearly.
• ERG is normal while EOG can be
variable.

44. NORTH CAROLINA MACULAR DYSTROPHY
• North Carolina macular dystrophy was
originally described in a family in North
Carolina.
• Now identified all over the world and in
various ethnic groups.
• Non progressive condition
• Transmit as autosomal dominant trait.
• Characterized by drusen in the posterior
pole leading to disciform scar .
• Sometimes staphylomatous chorioretinal
scars in the posterior pole.

45. Sorsby pseudoinflammatory Dystrophy
• This condition was first described in five British families.
• Autosomal dominant condition.
• Mutations in the tissue inhibitor of metalloproteinase-3 (TIMP- 3) have
been identified as a possible cause of the disease.
 SYMPTOMS:
• The disease presents as reduced central vision along with night blindness.
 SIGNS:
• Choroidal neovascular membrane (CNVM) formation .
• subretinal haemorrhage followed by disciform scar formation
• sometimes extending to the periphery as well.

46. Cont.
Confluent flecks
nasal to the disc
Exudative
maculopathy
Subretinal Scarring
in end-stage
disease

47. DOMINANT FAMILIAL DRUSEN
 Familial Dominant Drusens (Doyne honeycomb
choroiditis) represents a early onset variant of ARMD.
 Autosomal Dominant. Mutation in EFEMP1 gene
 Asymptomatic yellow-white, elongated, radially
oriented drusen develop in the second decade.
 With age the drusens increasingly become dense
and acquire a honeycomb pattern
 Described as ‘stars in the sky’ or ‘milky way’ they
seen in clusters in the posterior pole.
 Visual symptoms may occur in 4th to 5th decade
due to RPE degeneration, geographic atrophy or
occasionally CNV.
 ERG is normal, EOG is subnormal.

48. Dominant Cystoid Macular Dystrophy
• Dominant cystoid macular dystrophy (DCMD) was
described in 1976 ..
• Autosomal dominant condition.
• Chromosomal location of the gene to the short arm of
chromosome 7
• Characterized by EARLY leaking perimacular capillaries,
whitish punctate deposits in the vitreous,
• In the LATE stages of the disease, an atrophic changes
• Central “beaten-bronze” macula is common.
• A normal ERG, subnormal EOG, and hyperopia .

49. Central Areolar Choroidal Dystrophy
• This disease has a characteristic fundus
picture with punched out area of
chorioretinal atrophy in the macular area.
• Barring large choroidal vessels, all other
layers are atrophic in the affected area in the
late stages.
• In the early stages, non-specific granular
pigmentation can be seen that can be
confused with other conditions such as
Stargardt’s disease. central areolar choroidal
dystrophy.

50. Sjogren-Larsson syndrome
 Inheritance-Autosomal Recessive.
 It is a neurocutaneous disorder characterized
by congenital ichthyosis and neurological
problem.
 Pathology- Defective enzyme Fatty Aldehyde
Dehydrogenase.
 Presentation- Photophobia, Poor vision,
Glistening yellow-white crystalline deposits
develop at the macula.
 Presents in first 2 years of life.
 Associated features- Pigmented retinopathy,
Cataract, Colobomatous microphthalmos.

51. Generalized Choroidal Dystrophies

52. Choroideremia
 Also known as Tapeto-choroidal dystrophy.
 Progressive diffuse degeneration of the choroid, RPE and
Photoreceptors.
 Inheritance is XLR with the locus on Xq21.2 (CHM gene).
 Female carriers show mild, patchy peripheral RPE atrophy and
mottling
 Presentation is in the 2nd–3rd decades with nyctalopia, followed
some years later by loss of peripheral vision.
 Signs - 1) Mid-peripheral RPE abnormalities. 2) Atrophy of the RPE
and choroid spreads peripherally and centrally. 3) End-stage disease
shows a few large choroidal vessels coursing over the bare white
sclera, vascular attenuation and optic atrophy. In contrast to primary
retinal dystrophies, the fovea is spared until late

53. ERG- Scotopic is non-recordable;
photopic is severely subnormal.
 FA shows filling of the retinal
and large choroidal vessels but
not of the choriocapillaris. The
intact fovea is hypofluorescent
and is surrounded by
hyperfluorescence due to an
extensive window defect

54. Gyrate atrophy
 Inheritance is AR with the gene locus on 10q26.
 Presentation is in the 1st–2nd decades with myopia and nyctalopia.
 Signs-
1. Mid-peripheral depigmented spots associated with diffuse pigmentary mottling
may be seen in asymptomatic cases.
2. Sharply-demarcated circular or oval areas of chorioretinal atrophy that may be
associated with numerous glistening crystals at the posterior pole
3. Coalescence of atrophic areas and gradual peripheral and central spread
4. The fovea is spared until late
5. Extreme attenuation of retinal blood vessels.
6. Vitreous degeneration and early-onset cataracts are common.
 FA shows sharp demarcation between the choroidal atrophy and normal
filling of the choriocapillaris.
ERG is subnormal is early disease and later becomes extinguished.

55. Cont.
 Treatment
 There are two clinically different subtypes of
gyrate atrophy based on response to pyridoxine
(vitamin B6), which may normalize plasma and
urinary ornithine levels.
 Patients who are responsive to vitamin B6
generally have a less severe and more slowly
progressive clinical course than those who are
not.
 Reduction in ornithine levels with an arginine-
restricted diet is also beneficial.
 Prognosis is generally poor with blindness
occurring in the 4th–6th decades from
geographic atrophy, although vision may fail
earlier due to cataract, CMO or epiretinal
membrane formation.

56. Progressive Bifocal Chorioretinal Atrophy
 Inheritance- AD, with complete penetrance.
Ocular Manifestation-
 An initial focus of atrophic retina and choroid is seen
temporal to the disc.
 The focus enlarges in all directions and temporal
border typically has a serrated edge.
 The atrophy extends to the equator, it does not cross
the vertical midline. The end stage fundus
appearance has the unusual image of two separate
foci of chorio-retinal atrophy, with intervening
segment of normal retina.
Treatment & Course of Disease- present at birth
and is progressive. Visual acuity loss
corresponds to its proximity to fovea. No
effective treatment.

57. Vitreo-Retinopathies

58. X-LINKED JUVENILE RETINOSCHISIS
• This X- linked recessive condition is bilateral maculopathy
with poor prognosis.
• The disease is caused by mutations in the retinoschisis
associated gene (RS1) which is located on the distal arm
of the X chromosome.
• The protein retinoschisin is expressed only in the retina,
in the inner and outer retinal layers.
• Misfolding of the protein, failure to insert into the
endoplasmic reticulum membrane and abnormalities
involving the disulfide linked subunit assembly have been
found to be abnormalities causing retinoschisis.

59. Clinical features
• Difficulty in reading.
• VA deteriorates during 1st two decades.
• But remain stable until 5thor 6th decades .
• Squint or nystagmus occurs in infancy
• Associated with peripheral retinoschisis &vitreous
haemorrhage
• Macular RPE atrophy occurs leading to gross loss of central
vision
• Silvery peripheral dendritic figures, vascular sheathing &
flecks are common
• It differs from retinal detachment in being bilateral usually,
with taut dome like elevation without undulations, thin
inner layer.

60. Investigation
• FAF shows spoke like patterns & central
hypoautofluorescence with surrounding
hyperautofluorescence
• OCT cystic space in inner nuclear & outer plexiform
layer.
• FA: window defect

61. Treatment
• Topical or oral carbonic anhydrase inhibitors(dorzolamide 3 times daily)
• Vitrectomy is recommended for vitreous hemorrhage and retinal
detachments.
• Retinal detachment cannot be ruled out .
• When it does not clear in a short period, pars plana vitrectomy can clear
the hemorrhage.
• RD due to breaks in the outer layer in the periphery by scleral buckling.
• Gene therapy

62. Stickler Syndrome
 Disorder of collagen connective tissue.
 Inheritance is AD or AR. The commonest inherited
cause of retinal detachment in children.
 Classification: (STL1-3 = AD, STL4-5 = AR)
1. STL1 is the most common, mutations in the
COL2A1 gene. These subjects have the classic
ocular and systemic features as originally described
by Stickler.
2. STL2 is caused by mutations in the COL11A1 gene.
These subjects have congenital non-progressive
high myopia, sensorineural deafness, and other
features of Stickler syndrome type 1.
3. STL3 is due to mutations in the COL11A2 gene.
These subjects have the typical systemic features,
but no ocular manifestations.
4. STL4- STL5 are extremely rare.
 Systemic features: Facial anomalies, Skeletal
involvement, Sensorineural deafness.

63. Cont.
Presentation is in early childhood with high non-
progressive myopia.
Signs
 In STL1 -optically empty vitreous, a retrolenticular
membrane and circumferential equatorial membranes
that extend a short way into the vitreous cavity
 In STL2 patients the vitreous has a fibrillary and beaded
appearance
 Radial lattice- like degeneration associated with RPE
hyperplasia, vascular sheathing and sclerosis
 Retinal detachment develops in approximately 50% in the
first decade of life, often as a result of multiple or giant
tears that may involve both eyes.
 Associations Presenile cataract, Ectopia lentis, Glaucoma

64. Cont.
Treatment:
1. Prophylactic 360 retinal laser or cryotherapy may reduce incidence of RD.
2. RD repair is challenging and vitrectomy is indicated.
3. In case of cataract preoperative retinal evaluation with treatment should be
done first.
4. Glaucoma can be managed as congenital glaucoma.

65. Wagner Syndrome
 Shows similar vitreous changes to Stickler syndrome
 Not associated with systemic abnormalities.
 Inheritance is AD
 Presentation is in early life with pseudostrabismus
due to congenital temporal displacement of the fovea
with a positive angle kappa, and nyctalopia.
 Signs –
 The vitreous is optically empty with complete absence of
normal scaffolding.
 Avascular greyish-white preretinal membranes extending
from the posterior pole to the periphery
 Progressive chorioretinal atrophy.
 Nyctylopia commonly found
 Cataract and glaucoma

66. Cont.
 FA shows non-perfusion due to gross loss of
the choriocapillaris.
 ERG may initially be normal and then shows
reduction of scotopic b-wave amplitudes and
diffuse cone-rod loss.
 Prognosis is poor.
 Retinal breaks and detachment are treated as
they occur.

67. Take Home Message
• With continious improving technology and increasing experties
of clnician we have gain the ease of diagnosing Retinal
dystrophy
BUT
Considering effective treatment we are still lagging behind
• Recognising the condition timely and proper rehabilitation
should be the approach of management.