Ptosis; Third Nerve Palsy; Fixed Dilated Pupil; SubnuclearPtosisThe patient is a 76 year old woman who woke one morning unable to see out of her right eye because of ptosis. She came to the Massachusetts General Hospital emergency room and was admitted. Neurological Examination: Right third nerve palsy involving the pupil Ataxia of the left hand on finger-nose test Diagnosis: Claude's Syndrome - a lesion of the third nerve fascicle in the midbrain with involvement of the superior cerebellar peduncle. Fascicular third nerve palsies are rare. Lesions of the third nerve fascicle can present as an isolated complete or incomplete third nerve palsy, in association with other neurologic signs due to involvement of adjacent midbrain structures. F...