Ocular Dz 4: Retinal Dystrophies I

Front 1

What's the management of Albinism?

Back 1

Ocular Problems:
1. Most require HIGH refractive error
2. Tinted lenses helpful for light sensitivity
3. Low Vision (LV) services
- May benefit MANY albino patients

Systemic Problems:
1. Oculocutaneous albinos have increased risk of BCC & SCC
2. Several systemic syndromes associated with tyrosinase + oculocutaneous albinism, such that hematologic consultations, etc. may be indicated.
3. Genetic counseling may be appropriate.

Front 2

What's the management of Retinitis Pigmentosa (RP)?

Back 2

1. NO effective treatment at this point
- Vitamin A controversial, gene therapy?
2. Prognosis varies (with inheritance pattern)
- some read throughout life, many end up 20/400.
3. Yearly review for treatable vision loss.
- Cataract or CME (responds to oral acetazolamide)
4. Genetic counseling may be indicated
5. Many eventually benefit from LV services.

Front 3

What's the management of Stargardt's Disease?

Back 3

1. NO effective treatment at present
2. Prognosis generally poor
- initial gradual loss of VA tends to accelerate once hits 20/40 (often stabilizing around 20/200)
- those in whom macula initially unaffected may retain good vision until macula becomes involved.
- in rare instances, CNV may develop with devastating affect on vision.
3. LV services may be beneficial when there is significant visual loss.

Front 4

What's the management for Progressive Cone Dystrophy?

Back 4

OD Management:

1. Correct diagnosis important (despite lack of effective tx) for:
- accurate prognosis
- avoidance of unnecessary testing/procedures

2. Coordination of low vision services when become necessary for these patients.

Front 5

What's the management for Congenital Stationary Night Blindness?

Back 5

OD Management?

1. Only requires proper diagnosis
- usually evident from symptoms & signs (if any)
- unique ERG may help to confirm

2. NO treatment available

3. Functional impairment primarily limited to scotopic vision (GOOD VA the norm)

4. NO need for further testing or referrals.

Front 6

What are some diagnostic methods for Retinitis Pigmentosa (RP)?

Back 6

Diagnosis is based on characteristic collection of signs & symptoms, aided by the following:

1. Visual Fields
- Initial mid-peripheral scotoma expands over time

2. Electroretinography (ERG)
- Scotopic function reduced early (extinguished late)

3. Dark Adaptometry
- prolonged DARK adaptation

Front 7

What are some diagnostic methods for Albinism?

Back 7

1. Oculocutaneous albinism usually apparent, as is ocular albinism after SLE & DFE.

2. Hair bulb incubation reveals tyrosinase activity:
- Only reliable AFTER age 5.

Front 8

What are some diagnostic methods for Stargardt's Disease?

Back 8

1. Presentation of typical macular changes and/or surrounding "flecks" is suggestive

2. FA reveals characteristic "dark choroid" overall, with window defect at macula.

3. EOG usually abnormal (in advanced cases)

NOTE: Stargardt's Dz has a characteristic appearance, but if unsure, then use FA.

Front 9

What are some diagnostic methods for Leber's Congenital Amaurosis?

Back 9

Must be suspected when infants presented with roving eye movements or nystagmus.

1. Pupils - show little or NO response to light

2. Fundus - may initially appear normal

3. ERG - severely reduced or extinguished

Front 10

A devastating genetic disorder which affects both rods & cones from birth.

- The MOST common genetic cause of vision loss in infants & children.

- Blindness at birth (or shortly thereafter)
- Diagnosis usually made when parents seek care after noticing "wandering eyes"
- Associated with neurological, renal, bone, & endocrine abnormalities

Back 10

Leber's Congenital Amaurosis

Front 11

What are some diagnostic methods for Progressive Cone Dystrophy?

Back 11

Diagnosis based on course of macular/visual deterioration, assisted by:

1) FA may display RPE changes before seen clinically

2) ERG shows abnormal photopic responses

Front 12

A genetic defect affecting CONE photoreceptors primarily.

- Rods are UNAFFECTED or affected less/later than cones (Cone-Rod Dystrophy)
- Universally, leads to severe central vision loss (to 20/200 or worse)
1) Color vision also gradually deteriorates
2) Photophobia may follow visual loss
3) NO effective tx present

Back 12

Progressive Cone Dystrophy

Front 13

What are some SIGNS/SYMPTOMS for Progressive Cone Dystrophy?

Back 13

1. Presents in a child/young adult as gradual loss of central/color vision.

2. Macula (normal initially) develops subtle pigmentary changes which may progress to a "Bull's Eye" appearance --> geography atrophy

Front 14

A group of genetic disorders characterized by defective night vision.

Back 14

Congenital Stationary Night Blindness

Front 15

What are some signs/symptoms for Congenital Stationary Night Blindness?

Back 15

- Presents very early in life
- Non-progressive (stable throughout life)
- May occur with either a normal/abnormal appearing fundus:

1. Oguchi's Disease
- Gold-yellow appearance due to rhodopsin regeneration
2. Fundus Albipunctatus
- pinpointed gold dots on fundus