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  #1  
Old 03-30-2013
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Neuro Neuroanatomy and cranial nerves

What should I expect in terms of Neuroanatomy? Also, does anyone have any cranial nerve reflex questions they can share? I need more practice on those. I have a tricky one here:
Neurologic examination of a 34-year-old man reveals a direct and a consensual light reflex in his left eye, but neither a direct nor a consensual light reflex in his right eye. Which of the following signs is also likely to be found during his examination?

A. Abbucted right eye
B. Absence of the right corneal reflex.
C. Absence of touch sensation of the right face
D. Hyperacusis of the right ear
E. Inability to close the right eye
F. Visal field defect of the right eye
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A. Abbucted right eye
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A is the correct answer.
Here is another question:

Lateral conduction on Right ear - Weber
Air>bone on right and Air>bone on left -Rhine

Answer?
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Quote:
Originally Posted by OMGStep View Post
A is the correct answer.
Here is another question:

Lateral conduction on Right ear - Weber
Air>bone on right and Air>bone on left -Rhine

Answer?
Sensorineural hearing loss on left
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Yes! You are correct! If you can find some cranial reflex questions to post that would be great. The problem is that there are not too many of these questions to practice on so it's hard to master them.
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Another question: Light reflexes

1.Right optic nerve is damaged prior to the pre-tectal nucleus (AKA afferent defect). What light reflex will be seen in both eyes?

2.What light reflexes will be seen in both eyes if the right oculomotor nerve is damaged (AKA efferent defect)
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Another question: Light reflexes

1.Right optic nerve is damaged prior to the pre-tectal nucleus (AKA afferent defect). What light reflex will be seen in both eyes?
Light in left both pupils constrict/light in right-neither

2.What light reflexes will be seen in both eyes if the right oculomotor nerve is damaged (AKA efferent defect)
Light in left left left pupil constriction
Light in right left pupil constriction
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Can you explain #2. I don't understand it.
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Quote:
Originally Posted by OMGStep View Post
Can you explain #2. I don't understand it.
When oculomotor nerve is damaged u have no response to light in that eye but as far as pretectal nucleus is functioning impulse is spread to both EW nuclei and u get only CN3 response in unaffected left eye

Similarly when light is shone to left eye both EW nuclei are stimulated but only functioning CN3 (left) causes pupilary constriction
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Another question: Can you please explain the answer
60 y woman
right facial numbness
history of diplopia
PE decreased sensation, decreased messater power, decreased muscle strangth of all muscle at right side

corneal reflex will be:
a- consensual but not direct at left eye
b- consensual but not direct at right eye
c- consensual and direct at right eye
d- consensual and direct at left eye
e- no direct no consensual at right eye
f- no direct no consensual at left eye
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Quote:
Originally Posted by OMGStep View Post
Another question: Can you please explain the answer
60 y woman
right facial numbness
history of diplopia
PE decreased sensation, decreased messater power, decreased muscle strangth of all muscle at right side

corneal reflex will be:
a- consensual but not direct at left eye
b- consensual but not direct at right eye
c- consensual and direct at right eye
d- consensual and direct at left eye
e- no direct no consensual at right eye
f- no direct no consensual at left eye
I dont understand the options given
Is it D ?
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I don't understand them either. I hoped you would know. I saw this on a forum posting back in 2009 and some ppl were saying that the answer is e. But I have nooooo idea.
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Quote:
Originally Posted by OMGStep View Post
Another question: Can you please explain the answer
60 y woman
right facial numbness
history of diplopia
PE decreased sensation, decreased messater power, decreased muscle strangth of all muscle at right side

corneal reflex will be:
a- consensual but not direct at left eye
b- consensual but not direct at right eye
c- consensual and direct at right eye
d- consensual and direct at left eye
e- no direct no consensual at right eye
f- no direct no consensual at left eye
She lost both CN V (afferent) and CN VII (efferent) on the right side, so (e) no direct and no consensual at right eye
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Oops i missed the clues
Lady has both involvement of trigeminal nerve (decreased sensation) + weakness of all muscles (CN7)
So we got destruction of both afferent arm and efferent arm
when u touch right cornea its not going to blink cause trigeminal is affected on that side
When u touch left cornea left eye gonna blink but right eye is unable cause CN7 is affected on right side
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