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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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Third nerve palsy with pupillary sparing is seen in all except:
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The correct answer is  Answer is B (Aneurysm of posterior communicating aery): If the pupil is entirely normal, with all other components of an occulomotor palsy present aneurysm is so rare that an angiogram is seldom indicated. - Harrison Isolated pupil-sparing occulomotor palsy Most cases are thought to result from microvascular infarction of the nerve. Somewhere along its course from the brainstem to the orbit Major risk factors are: Diabetes Hypeension Vascular disease Major presentation is with pain. Spontaneous recovery over a period of months is the rule.