Flashcards in Fundus Deck (30):
What are the components of the fundus?
Retinal pigment epithelium (RPE)
Neurosensory retina (rods, cones, and retinal blood vessel)
T/F: lacking pigmented epithelium or the tapetum from the retina can be a normal variation
Occurs in light blue eyed dogs (husky)
T/F: the optic nerve is myelinated in dogs and cats
Myelinated in dogs
Absent in cats —> optic disc appears dark, round and small
What are hallmarks of retinal disease?
Altered tapetal reflectivity
Altered optic nerve Head appearance
What are possible causes of retinal hemorrhage?
Where can retinal hemorrhage be localized?
Pre- retinal (keel boat)
Within nerve fiber (flame-shaped)
Within retina (dot-blot)
Sub-retinal (diffuse, irregular)
What initial diagnostic work up do you do if you have a patient with retinal hemorrhage?
What are causes of retinal detachment?
Intraocular inflammation — chorioretintitis
Vascular disease — hypertension
What is retinal detachment ?
Separation of neurosensory retinal from RPE
Remains attached at ONH and oral ciliaris
Bulbous detachment of the retinal is an early sign of __________________ disease in cats
Feline hypertensive retinopathy
What is the treatment for bulbous retinal detachment associated with feline hypertensive retinopathy?
Antihypertensive therapy —amlodipine
What is retinal dialysis/
Compete retinal detachment AND tear
No longer attached at ora ciliaris
Retinal dialysis is a common occurrence with primary vitreous degeneration. What breeds are predisposed ?
How does the retina appear with retinal dialysis?
Tapetum is hyper-reflective because no overlying retina is there to absorbed light and the retinal is folded over the optic nerve
What is the treatment for retinal dialysis?
Partial detachments - retinopexy
-poor visual success rate
Increased tortuously of the vascular retina is associated with ??
In what cases can you get increased reflectivity of the tapetum?
In what cases can you have decreased reflectivity of the tapetum?
Increased retinal thickening
What are disorders of retinal degeneration?
Progressive retinal atrophy
Sudden acquired retinal degeneration syndrome
Feline central retinal degeneration
Drug-associated rental degeneration
What is progressive retinal atrophy?
Bilateral and symmetrical degeneration
GRADUAL Photoreceptor degeneration — causing night blindness initially then progressing to gradual loss of vision
What is the treatment for progressive retinal atrophy?
Clinical signs of progressive retinal atrophy?
Narrowing and loss of retinal blood vessels = attenuation
Optic nerve atrophy
Non-tapetal pigmentary changes
Secondary cataract formation
What is sudden aquired rental degeneration syndrome (SARDS)?
Bilateral and symmetrical
ACUTE photoreceptor death
-dilated pupils but fundus appears normal
SARDS is associated with what signalment?
Middle aged/older dogs
CBC and biochem are suggestive of hyperadrenocortisim but most cases do not have cushings
What is feline central rental degeneration?
Initial degeneration confined to ellipical area dorsolateral to ONH
Feline central retinal degeneration may be associated with what nutrional deficiency?
What antibiotic can cause retinal degeneration in cats
—- functional defects in ABCG2 allows drug to cross blood-retinal barrier
What is chorioretintitis?
Inflammation of the chronic (uvea) and retinal
Gray-white ares of edema or cellular infiltrate in the retina
Can aslo have retinal detachment, rentinal hemorrhage, vitreous haze, impaired vision, anterior uveitis
What work up will you do for chorioretintitis ?
Serology (fungal and tick titers)