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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Transtentorial uncal herniation compresses which cranial nerve -
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The correct answer is  Ans. is 'a' i.e., III * Uncal herniation can compress the third nerve, compromising the parasympathetic supply to the pupil, so that unopposed sympathetic activity produces an enlarged and sluggish pupil, which then, if the compression continues, becomes fixed and dilated.