Retina Review

Part 3

50 yo lifelong difficulty with night vision

CSNB

• What is the primary signal transduction defect in congenital stationary night blindness?– Failure of communication between

photoreceptor and bipolar cell– Loss of retinal ‘on-responses’

• What is the most common ERG pattern?– Negative ERG– Large a-wave on scotopic response– Absent or reduced b-wave

Fundus Albipunctatus

• What is the main symptom of fundus albipunctatus?– Nyctalopia

• Describe the pathophysiologic defect and findings on testing?– Disorder of visual pigment regeneration– Delayed recovery of rhodopsin levels after

light exposure– Prolonged dark adaptation– Normal ERG after several hours in dark

Night Blinding Disorders

• What is a variant of RP that has a similar appearance to fundus albipunctatus?– Retinitis punctata albescens

• How is this entity distinguished from fundus albipunctatus?– Attenuated vessels– Severely depressed ERG– No recovery with dark adaptation– Progressive (not stationary)

Retinitis Pigmentosa

• Describe the characteristic fundus appearance of RP– ‘Waxy pallor’ of the disc– Attenuated retinal vasculature– Bone-spicule pigmentation

• What else is seen clinically?– PSC cataract– Cystoid macular edema

• What is commonly seen on GVF and ERG?– ring scotoma– marked reduction of rod and cone function

Retinitis Pigmentosa

• Inheritance– 70% recessive– 20% dominant– 10% X-linked

• Variants– RP sine pigmento– Retinitis punctata albescens– LCA– Ushers

• Rx– Vitamin A may slow progression

30 yo 20/200 OU, nystagmus, no medical problems or meds

Cone Dystrophy

• Describe the symptoms of cone dystrophy– Progressive central visual loss– Dyschromatopsia– Photoaversion

• Describe the clinical findings– Bull’s eye maculopathy– Selective loss of cone function on ERG

25 yo 20/50 OU

Stargardt Disease• What is the typical inheritance pattern of Stargardt

disease?– Autosomal recessive

• What is the condition called if there are peripheral flecks with little macular involvement?– Fundus flavimaculatus

• What is a characteristic pattern on fluorescein angiography?– Dark choroid

• What is the typical range of visual acuity?– 20/50 to 20/200– Most retain 20/70 to 20/100 in at least 1 eye

40 yo 20/60 OD, 20/40 OS

Best Disease

• What is the inheritance pattern of Best disease and what chromosome is involved?– Autosomal dominant– 11

• What are the fluorescein angiographic findings?– Blockage by vitelliform material– Hyperfluorescence in areas of RPE atrophy

• Is the ERG typically abnormal?– No

• What is the typical level of visual acuity?– 20/40 or better

Best Disease

• What is the critical diagnostic test and what findings would one expect?

– EOG– Decreased Arden ratio (<1.5; often 1.1)

50 yo 20/200 OU

Gyrate Atrophy

• What is the mode of inheritance of gyrate atrophy?– Autosomal recessive

• What is the enzymatic defect?– Ornithine aminotransferase

• What is the typical visual acuity in most patients by age 40?– 20/200 or worse

• What is the pathognomonic serum finding and how can this be addressed?– Elevated ornithine– Arginine restriction

30 yo male 20/200 OU

Choroideremia• What is the mode of inheritance of choroideremia?

– X-linked recessive

• What is the typical visual acuity by age 50?– 20/200 or worse

• What are the ERG findings of affected males and female carriers?– Males: subnormal early; extinguished late– Females: normal

• For what enzyme does the abnormal gene encode?– Rab geranylgeranyl transferase

20 yo male 20/40 OU

Juvenile Retinoschisis

• What is the mode of inheritance?– X-linked recessive

• What layer is schisis supposed to occur?– Nerve fiber layer

• FA leakage?– No

• ERG?– Loss of b wave (negative)

Bardet-Biedl Complex

• Describe the clinical findings in Bardet-Biedl syndrome– Obesity– Polydactyly– Hypogonadism– Mental retardation– Pigmentary retinopathy

• What is the mode of inheritance – Autosomal recessive

• How is the ERG affected?– Undetectable or severely impaired

1 mo old baby

Tay-Sachs Disease

• What is the enzyme deficiency in Tay-Sachs disease?– Hexosaminidase A

• Explain the pathophysiology– Glycolipid accumulation in the brain and retina leads

to mental retardation and blindness– Death occurs between 2 and 5 years

Bietti’s crystalline retinopathy

• What is mode of inheritance? – Autosomal recessive

• Clinical findings?– Pigmentary and crystalline retinopathy– Corneal crystals– Progressive decrease in vision starting in 40s

• Treatment?– No effective treatment

Medications

• Crystals?– Tamoxifen– Canthoxanthine– Talc

• Pigmentary retinopathy?– Thorazine– Mellaril

• Bullseye?– Plaquenil (6.5 mg/kg/d)– Chloroquine (250 mg/d)

20 yo hit in OS

Day One Post-injury

One Month Post-Injury

Commotio Retinae

• Describe the pathophysiology– Damage to outer retinal layers caused by shock

waves– Retinal whitening within hours of injury– Proposed mechanisms:

• Extracellular edema• Glial swelling• Photoreceptor damage/disorganization of outer

segments

• What is the typical time for resolution?– 3 to 4 weeks

• What are 2 causes for limited visual recovery?– Macular pigment epitheliopathy– Macular hole formation

18 yo s/p trauma to right eye

Choroidal Rupture

• Describe the mechanism– Anterior-posterior compression– Stretching in horizontal axis– Tearing of Bruchs membrane along with RPE and

choriocapillaris

• What is the most visually threatening complication?– Choroidal neovascularization

16 yo shot with BB

Intraocular Foreign Body

• What is caused by retained copper foreign bodies?– Chalcosis

• What are the findings of chalcosis?– Deposits in Descemets membrane– Greenish aqueous particles– Green iris discoloration– Sunflower cataract– Vitreous opacities– Metallic retinal flecks

Intraocular Foreign Body• What condition is caused by retained iron

foreign bodies?– Siderosis bulbi

• Describe the findings?– Corneal stromal staining– Iris heterochromia– Pupillary mydriasis & poor reactivity– Anterior lens deposits and cataract– Peripheral and diffuse retinal pigmentation– Narrowed vessels– Optic atrophy

• What are ERG findings?– Increased a-wave and normal b-wave early– Progressive diminution of b-wave amplitude

40 yo s/p ruptured globe OS; OD 20/40, AC cell

Sympathetic Ophthalmia

• What is the reported range of time interval from initial injury to development of SO?– 5 days to 66 years

• What uveitic entity most closely resembles SO and how can they be differentiated?– VKH– History of ocular trauma or multiple surgical interventions– VKH involves choriocapillaris; SO spares it

Sympathetic Ophthalmia

• What are possible extraocular manifestations shared with VKH?– Vitiligo– Poliosis– Alopecia– Dysacusis– Meningeal irritation– CSF pleocytosis

• What are the fundus lesions called and how do they appear on fluorescein angiography?– Dalen-Fuchs nodules– Early hypofluorescence with late hyperfluorescence

Sympathetic Ophthalmia

• What is the treatment for SO?– Corticosteroids– Cyclosporine A– Azathioprine/Methotrexate

3 mo old; consult from PICU

Shaken Baby Syndrome

• What are the ocular signs?– Retinal hemorrhages– Cotton wool spots– Retinal folds– Schisis cavities

• What disorders can lead to hemorrhage in the vitreous cavity, sub-ILM space, subretinal space, and sub-RPE space?– Shaken baby syndrome– Trauma– Exudative AMD– Retinal arterial macroaneurysm

20 yo s/p MVA; NLP OD

Valsalva Retinopathy

• Describe the pathophysiology– Sudden rise in intra-abdominal pressure (cough, etc)– Corresponding rise in intraocular venous pressure– Rupture of macular capillaries– Hemorrhage

• What is the typical location of hemorrhage?– Sub-ILM

• What is the typical visual prognosis?– Excellent– Spontaneous resolution within months

Purtschers Retinopathy

• What are the etiologies? – Acute compression injury to thorax or head – Acute pancreatitis– Fractures

• Describe the pathophysiology– Activation of complement with granulocyte

aggregation and leukoembolization– Complement-mediated leukostasis and obstruction– Formation of cotton wool spots, hemorrhage, & edema– Fat embolization for fractures

• What is seen on fluorescein angiography?– Arteriolar obstruction– Vascular leakage