title: Unilateral pupillary dilatation during focal seizures.
abstract: Pupillary dilatation was observed in a young boy who had a sudden onset of right focal seizures. Clinical and laboratory investigation revealed the presence of a benign left frontal epileptic focus. Lacking signs of third cranial nerve compression, this transient pupillary abnormality could be caused by the contralateral frontal epileptic focus. Such a focus might inhibit dilatation of the homolateral pupil, thus permitting dilatation of the contralateral pupil only. Unilateral mydriasis as described hereby could also represent a pupillary "Todd's Paralysis" caused by the contralateral frontal epileptic focus.
mesh_terms: D000293:Adolescent; D004108:Dilatation, Pathologic; D004292:Dominance, Cerebral / Q000502:physiology; D004569:Electroencephalography; D004828:Epilepsies, Partial / Q000175:diagnosis*; D005625:Frontal Lobe / Q000503:physiopathology; D006801:Humans; D008297:Male; D012025:Reflex, Pupillary; D014057:Tomography, X-Ray Computed