Ocular disease Pt 2 Flashcards
Asteroid hyalosis
What is it made up of?
associated with aging over 60 yo
made with calcium soaps
What are the signs and symptoms of asteroid hyalosis?
Sx: asymptomatic, no floaters
signs: numerous small, yellow-white refractile particles attached to collagen fibrils in a normal vitreous, unilateral in 75% of cases
Synchysis Scintillans
usually found AFTER a anterior chronic uveitis, vitreous heme or trauma
made up of cholesterol crystals, unilateral golden brown, refractile that are freely mobile in the vitreous cavity and often settle inferiorly?
What’s the difference between asteroid hyalosis and synchysis scintillans?
Asteroid hyalosis - calcium soaps, occurs w/ normal aging
Synchysis scintillans - cholesterol crystal, settle inferiorly, occurs w/ chronic anterior uveitis/vit heme/trauma
BOTH UNILATERAL
PVD
- more common in females
- prevalence ~50 yo (50% by age 50 and 65% by age 65)
- can occur 20 years earlier in myopes
- collagen clumps causing the liberated collagens to contract –> causing PVD. Pockets of liquefaction (syneresis) can travel through the hole in the posterior hyaloid causing separation between the vitreous and the retina
What signs can aid in detecting a RD/break after a PVD?
schafer’s sign (tobacco dust) and vitreous heme (70% increase risk of a break)
What are risk factors for PVD?
diabetes, myopia, age, surgery, inflammation, vitreous heme, trauma
What are the signs and symptoms of a PVD?
Sx: acute floaters, decreased vision, flashes of light
Sign: Weiss ring, anterior displacement of the posterior hyaloid, pigmented cells (shafer’s sign), vit heme
What else can PVD result in?
erm, macular hole, VMT, vitreous and retinal heme, retinal breaks
If you see vitreous heme, what should you ask about?
trauma, diabetes, HTN
What can cause a vitreous heme?
trauma, DR VOS
Diabetes
ROP
Vein occlusion
OIS (ocular ischemic syndrome)
Sickle cell
What are the signs and symptoms of a Vitreous heme/pre-retinal heme ?
Pre-retinal heme: asymptomatic unless the macula is involved, sudden vision loss or VF loss
Vitreous heme can cause sudden, painless vision loss and/or black spots that have corresponding flashing lights
Signs:
Preretinal heme: located between the retina and posterior vitreous, very red and keel shape
Vitreous heme: anterior to the posterior vitreous face (within the vitreous). mild vitreous heme will be characterized by blood that obscures only part of the fundus, severe heme will completely obscure the view of the fundus chronic cases will appear yellow
Whats the most common cause of a spontaneous vitreous heme?
DR (31-54% of cases)
What test should you order if you have a difficult time seeing the fundus through the vit heme
B-scan
What are the 2 types of neo? What causes each of them?
- Preretinal - DR VOS
- Choroidal - CHBALA
CRVO
- 3rd most common vascular cause of vision loss, DR is the most common
- compression of an artery on a vein leading to turbulent blood flow
- venous vessel walla damage, thrombus formation, thrombus at or near lamina cribosa
What are the risk factors for CRVO
HTN, diabetes, cardiovascular dz, open-angle glc
what’s the ocular dz that’s most commonly associated with CRVO?
Glaucoma/POAG (40-60%)
What are the causes of CRVO or BRVO in a young patient?
a young pt with clotting issues
oral contraceptive, protein S/ protein C/ antithrombin III deficiency, factor XII deficiency, antiphospholipid antibody syndrome, collagen vascular dz, and AIDS
What are the signs and symptoms of a CRVO?
sudden, unilateral, painless vision loss in an elderly pt ( 90% of pts are >50 yo)
signs:
thrombus formation leads to ischemia and release of VEGF with characteristic signs including retinal heme in all 4 quads, collaterals, dilated tortuous retinal veins, CWS, optic disc edema
** remember veins drain blood from the retina**
Collateral veins
visible over several weeks to months, often on the disc and permits blood flow between the retina and choroidal circulations
helping to accelerate drainage of excessive fluid (retinal edema) into the choroidal circulation after a CRVO
What are some vision-threatening complications that CRVO can cause?
- Macular edema, macular ischemia, intramacular hemes
- Neo (BAD!!),
- 90-day glaucoma (within first 3 months of diagnosis of CRVO)
ischemic CRVO
-60% of ischemic cases develop iris neo and 30% develop neo glaucoma
- higher risk of neo glaucoma
non-ischemic CRVO
6% of nonischemic cases develop rubeosis or angle neo
ALWAYS DO GONIO
What is the leading cause of vision loss in ischemic and non-ischemic CRVO?
macular edema
What defines ischemic CRVO?
10DD or more of nonperfusion on FA
- 90% of cases are 20/200 or worse
- poor prognosis, final VA CF
16% of nonischemic cases become ischemic