Retina and Optic Nerve

What are msot inherited retinopathies?

Autosomal recessive

What are the C/S of progressive retinal atrophy?

Bilateral progressive loss of vision

Decreased night vision

Decrease in PLR

Larger than normal resting pupil

Cataracts late stage

What is nyclatopia?

Decreased night vision

What are the 3 hallmark fundoscopic signs of progressive retinal atrophy?

1. Tapetal hyperreflectivity

2. Thin retinal vessels

3. Optic disc color change

What is SARDS?

Sudden Acquired Retinal Degeneration Syndrome

What causes SARDS?

Acute photoreceptor death

What is the signalment for SARDS?

Middle aged to older dogs that affects all breeds

What is an associated C/S of SARDS?

Cushing’s-like signs for weeks or months prior to vision loss

What are the C/S of SARDS?

Acute vision loss

Variable PLR

Normal fundic abnormalities initially

How do you diagnose SARDS?

Electroretinogram

Cushing’s like changes like elevated ALP

How do you treat SARDS?

No treatment, quality of life for a blind pet is fine

What is the visual deficit of a small retinal detachment?

Nothing

T/F it takes a large retinal detachment to cause a visual deficit or blindness?

True

What is a rhegmatogenous retinal detachment?

Retinal tear which allows for liquefied vitreous to enter sub retinal space

T/F hematogenous retinal detachment is a primary ocular disorder?

True

Describe non-rhegmatogenous retinal detachment

Remains attached at ora ciliaris retinae and optic disc

Caused by systemic disease

Rhegmatogenous retinal tear

Non-rhegmatogenous retinal detachment

What are your differentials for an exudative non-rhegmatogenous RD?

Systemic infection

What are your differentials for a transudative non-rhegmatogenous RD?

Hypertension

Hypoproteinemia

Idiopathic

What should you do every time you have a non-rhegmatogenous retinal detachment?

Systemic work up with

• CBC/UA

• BP

• Chest radiographs

• Titers/antigens tests

What type of retinal detachment can you fix with surgery?

Rhegmatogenous detachments

What procedure can repair a Rhegmatogenous detachment?

Laser retinopexy

What is the etiology of retinal hemorrhage?

Systemic hypertension

Systemic infections that cause vasculitis

How do you work-up retinal hemorrhage?

Thorough physical exam

Platelets, chem panel, UA

Blood pressure

What is optic neuritis?

Unilateral or bilateral inflammation of the optic nerve

T/F optic neuritis can involve any segment of the optic nerve?

True

What is optic neuritis associated with?

Sudden blindness, fixed and dilated pupils

Describe intraocular optic neuritis signs

Swollen, elevated disc and hyperemic with indistinct margins

Describe retrobulbar optic neuritis signs

Optic disc appears normal

How do you distinguish retrobulbar optic neuritis from SARDS?

ERG