This patient has sudden onset diplopia and the Hess's chart is as shown above. a. What is the diagnosis? b. What is the most important physical sign in this patient?
a. What is the diagnosis?
b. What is the most important physical sign in this patient?
Answer a A left third nerve palsy. In Hess's chart, the abnormal eye has the smallest chart ie. the left eye. The underaction of all extraocular muscles except for the lateral rectus and superior oblique suggest a third nerve palsy. Answer b Presence or absence of left mydriasis. A sudden onset third nerve palsy with pupil involvement suggests an intracranial aneurysm until proven otherwise.
