Pupil's problems BQ'

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Pupil's problems BQ'

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Believe
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12/01/05 - 11:40 AM

A 48-year-old man comes to his physician because his wife noticed that his right pupil is "small." Physical examination shows that the right pupil is constricted and does not react to light. His left pupil is normal. These findings are most likely due to a lesion involving which of the following structures on the right?<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

A) Cervical spinal cord

B) Frontal eye fields

C) Lateral geniculate nucleus

D) Optic tract

E) Visual cortex

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roopashri
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12/01/05 - 01:59 PM

its A... horners syndrome

reet
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12/01/05 - 02:00 PM

A) ???? PUPIL IS CONSTRICTED CUZ NO SYMPATHETIC SUPPLY. (IN HORNER SYNDROME)

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Believe
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12/05/05 - 12:34 PM

all lesions past the chiasm produce contralateral defects, thus cancel c)d)e); frontal eye field regulates voluntary contralateral horizontal gaze, not involved in pupil's reaction.

A)cervical spinal cord -- most likely related with Horner's syndrome whic is due to lesion on cervical sympathetic nerves.

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roopashri
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12/05/05 - 12:57 PM

wow, great pics, keep up the gr8 job

Musuq
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10/19/06 - 07:36 PM

horner 4 sure

MRMAVERICK
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10/20/06 - 05:54 PM

YUP A

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ManuNastai

11/05/06 - 01:55 AM

from the answers given I agree A even if it's not the exact answer. The presynaptic Sy. neurons in the circuit that is damaged here originate in the thoracic spinal cord; they ascend and make synapse in the upper cervical Sy. ggl.

ssrpk
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11/05/06 - 02:02 AM

cervical spinal cord contains descending hypothalamic fibers which descend down to the level of the thoracic spinal cord and emerge to synapse in the cervical ganglion!

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Ig F
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12/04/06 - 01:54 AM

#10

itz A ....HYPOTHALAMIC FIBERZ PRODUCE IPSILATERAL HORNER'S SYND.

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