title: Mesencephalic hemorrhage and unilateral pupillary deficit.
abstract: An isolated dilated and fixed pupil in the absence of other neurological dysfunction usually suggests ciliary ganglion dysfunction or direct pharmacological blockade of the parasympathetic fibers to the pupil. A unilateral dilated pupil as a manifestation of a mesencephalic hemorrhage has not, to our knowledge, previously been reported. We now describe a 35-year-old woman who had a headache and a dilated and nonreactive right pupil. A cranial computed tomography scan showed a small hemorrhage in the midbrain, and a cerebral angiogram was normal. Mesencephalic hemorrhage should be considered in the differential diagnosis of an isolated dilated pupil.
authors.affiliation: Foothills Hospital, Calgary, Alberta, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Shuaib
authors.forename: G
authors.initials: G
authors.lastname: Israelian
authors.forename: M A
authors.initials: MA
authors.lastname: Lee
mesh_terms: D000328:Adult; D002543:Cerebral Hemorrhage / Q000150:complications*; D005260:Female; D006801:Humans; D008636:Mesencephalon; D011680:Pupil / Q000473:pathology*; D012025:Reflex, Pupillary; D014057:Tomography, X-Ray Computed