A Simple One # 3

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A Simple One # 3

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new_n_lost
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12/09/07 - 02:33 PM

A 60-year-old man suddenly becomes completely blind in one eye, and angiography demonstrates occlusion of the central retinal artery.

Which of the following is the most likely cause of the occlusion?

A. Atheroma or embolism
B. Cranial (temporal) arteritis
C. Hypertension
D. Polycythemia vera
E. Tumor

I know half of you guys will go yeah right !!

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hope4dabest
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12/09/07 - 06:51 PM

m confused b/w A and B.....
so i will go with B
but i think even embolus causes suddenly

dabears2356
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12/09/07 - 08:16 PM

i would guess B but then..its female dominat..so cant say that for sure.
for A --> emobli in retinal A. would be from L.heart, would have to be a small thrombus but dont know if infarction would only cause blindness and no other cc.

i think if A is right..then D can be right as well..caz polycythemia would produce infarct as well.
so i guess by process of elimination..B would be right..lol. so plz tell us.

keepgoing
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12/09/07 - 11:08 PM

B.(TA)

silver
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12/10/07 - 05:34 AM

A. Atheroma or embolism

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keepgoing
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12/10/07 - 05:40 AM

oh right silver,thanks,yes its emboli,TA not that common and its typical in females and no such description in question so overall cause shud be emboli not TA or PV or others

A.

jean robert
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12/10/07 - 09:14 AM

Why not B?

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Aashi
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12/10/07 - 11:33 AM

Atheroma or embolism is the MCC of central RAO..------->A

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silver
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12/10/07 - 11:38 AM

jean robert wrote:
Why not B?

what's your reason for B?

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doc_clotaire
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12/10/07 - 01:38 PM

#10

BIG TIME

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new_n_lost
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12/10/07 - 02:35 PM

#11

Nice to see some big guns still active.
wink

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new_n_lost
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12/10/07 - 02:36 PM

#12

silver wrote:
A. Atheroma or embolism

new_n_lost
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12/10/07 - 02:38 PM

#13

The correct answer is A.

The point of this question is that sometimes the obvious explanation is the correct one.

Occlusion of the central retinal artery rapidly causes irreversible blindness with loss of the inner retinal layers. (The photoreceptor rod and cone cells are maintained by the pigment epithelium.) The site of occlusion is typically just posterior to the cribriform plate. A garden-variety atheroma or embolism is overwhelmingly the most common cause of central retinal artery occlusion.

Despite all of the teaching about the risk of blindness in temporal arteritis (choice B), this disorder causes only 10% of central retinal artery occlusions.

Hypertension (choice C) is more apt to cause bleeding than thrombosis.

Polycythemia vera (choice D) could (rarely) cause occlusion because of increased blood viscosity and a tendency for thrombosis.

Tumor (choice E) might also cause retinal artery thrombosis, but this would be far rarer than atheroma.

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