Answer: This sounds like a difficult question, but it really isn’t. One trick for learning the cranial nerve locations is the 4-4 rule. That is to say, the bottom four brainstem nuclei (12,11, 10, and 9) sit in the medulla, while the next four (8, 7, 6, 5) are in the pons.
Cranial nerve 4 and 3 lie under the inferior and superior colliculi. CN 2 is the optic nerve, and CN is the olfactory.
Knowledge of this brainstem anatomy really helps you localize a lesion. For example, if the patient has a 6th nerve palsy and problems with hearing (CN7), the lesion is probably in the pons. If all the eye nerves 3,4,6 are gone and the patient is otherwise “OK,” then this lesion is probably NOT in the brainstem as any lesion big enough to hit BOTH the pons and midbrain would cause other systemic problems.
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its written over here that “in problems oh hearing(CN7)” while it shud be CN8—-its the auditory nerve concerned with hearing and not the facial nerve which is the 7th cranial nerve….
Comment by akshat goel — August 31, 2009 @ 11:29 am
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its written over here that “in problems oh hearing(CN7)” while it shud be CN8—-its the auditory nerve concerned with hearing and not the facial nerve which is the 7th cranial nerve..
Comment by akshat goel — August 31, 2009 @ 11:31 am
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