Eye: retinopathies

Question 1

what is the leading cause of NEW cases of legal blindness in adults?

Answer 1

diabetic retinopathy (DR) 
(1/3 of adults >40yo)

Question 2

major risk factor for developing DR

Answer 2

longer duration of DM, >50% of pt with DM >10-15 yrs

Question 3

what is the pathogenesis of DR?

Answer 3

basement membrane thickening of retinal arterial capillaries= dec. metabolic exchange & retinal nutrition = weaken vascular walls = microaneurysm & fluid leakage

• closure of capillaries = hypoxia & ischemia
• neovascular tufts
• hemorrhage in preretinal and vitreous space
• traction retinal detachment

Question 4

what is the earliest clinical sign of DR?

Answer 4

microaneurysms

Question 5

what are the 8 clinical features of DR?

Answer 5

1. microaneurysms (capillary wall outpouch)
2. dot/blot hemorrhage
3. flame heme
4. retinal edema/hard exudate
5. cotton wool spots
6. venous bleeding
7. IRMA- intraretinal microvasc. abnormalities
8. macular edema

Question 6

dot/bot hemorrhage vs flame heme

Answer 6

dot/blot: rupture microaneurysm in deeper layers of retina

flame: rupture in more superficial layer of retina

Question 7

retinal edema/hard exudates

Answer 7

loss of blood brain barrier

- leakage of proteins, serum & lipids from vessels

Question 8

cotton wool spots

Answer 8

nerve fiber layer damage

Question 9

what is the most sig. predictor of progression to PDR?

Answer 9

venous beeding- increasing retinal ischemia

Question 10

IRMA

Answer 10

intraretinal vascular abnormalities- remodeling of capillary beds w/out proliferation

Question 11

what is the leading cause of visual impairment for DR?

Answer 11

macular edema

Question 12

mild vs moderate vs severe nonproliferative DR?

Answer 12

mild- at least 1 microaneurysm
moderate- hemorrhages, microaneurysms, & hard exudates
severe- 4-2-1 hemes: microaneurysms in all 4 quadrants, venous beading in 2 quadrants, IRMA in 1 quadrant

Question 13

CSME- clinically sig. macular edema - 3 qualifiers

Answer 13

1. any edema w/in 500um of fovea
2. hard exudates w/in 500um of fovea w/ retinal thickening
3. retinal edema > 1disc size and w/in 1disc area of fovea

Question 14

4 ways to treat/manage DR? which for proliferative DR and ME? which for CSME? which for PDR, vitreal hemes and tractional detachments?

Answer 14

1. glucose control
2. anti-VEGF (avastin/lucentis) for proliferative and ME
3. laser photocoag-for CSME
4. vitrectomy - for PDR, persistent vitreal hemes, and tractional detachments

Question 15

what is the 2nd most likely cause of retinopathy?

Answer 15

HTN- early, advanced and severe forms

Question 16

early vs advanced vs severe HTN retinopathy

Answer 16

early: vessel wall thickening
advanced: altering caliber of light reflex of arteriorles- “copper wiring”
severe: vessel shunt and A/V compression - “silver wiring”–> hemorrhage, exudate and edema

Question 17

HTN retinopathy grading 1–>4

Answer 17

1. narrowing or sclerosis
2. focal narrowing and arteriovenous crossing, exaggerated arterial light reflex
3. retinal hemorrhages, exudates, cotton spots. sclerosis and spastic lesions of arterioles
4. severe grade 3 & papilledema

Question 18

management/ txt of HTN retinopathy

Answer 18

control BP

- treat edema & hemes: photocoag, anti-VEGF, corticosteroid injections

Question 19

what could be a cause of sudden painless unilateral loss of vision (partial or complete)?

Answer 19

vascular occlusion - blockage of retinal vasc

• central artery- loss of vision
• branch artery- partial loss of vision
• central vein vary in manifestation
• branch vein-unilateral blind spot

Question 20

what would you think if a pt presented with a macular “cherry red” spot and whitening of the retina ?

Answer 20

central retinal artery occlusion (CRAO)

Question 21

APD

Answer 21

afferent pupil defect: affected eye dilates w/ light instead of contstricts
-shows w/ CRVO and most optic nerve disorders

Question 22

CRVO- central retinal vein occlusion

Answer 22

blockage = stagnation of blood w/in retina

- hemes in 4 quadrants, tortuous veins (twisted), cottom wool spots, edema, neovasc.

Question 23

what is the leading cause of irreversible vision loss in adults over 50?

Answer 23

AMD- age-related macular degeneration

• progressive deterioration of central vision due to damage of RPE in macula
• “dry” and “wet”

Question 24

dry vs wet AMD

Answer 24

90% dry (non exudative): less severe but no txt

10% wet (exudative) : more severe- bleeding & swelling but can txt w/ anti-VEGF injection

Question 25

dry AMD

Answer 25

90% of AMD cases
RPE disruption from photoreceptor waste product- drusen
geographic atrophy w/ maturation

Question 26

wet AMD

Answer 26

90% of severe vision loss cases
neovascularization of choroid under macula
hemorrhages & edema
disciform scarring

Question 27

3 types of drug-induced/ toxic retinopathy

Answer 27

1. bull’s eye maculopathy
2. crystalline retinopathy
3. nutritional amblyopia

Question 28

bull’s eye maculopathy

Answer 28

drug: plaquenil
- damages macula leading to scotoma (blindspot)
- rare but loss is permanent

Question 29

crystalline retinopathy

Answer 29

drug: tamoxifen
-crystalline in RPE near macula- hemes and edema
may induce cataract

Question 30

alcohol/nutritional amblyopia

Answer 30

painless bilateral vision loss
retina may appear normal or have optic nerve pallor
-vision improves w/ supplement