"Fou rire prodromique" as the presentation of pontine ischaemia secondary to vertebrobasilar stenosis

"Fou rire prodromique" (prodrome of crazy laughter) is a rare form of patho logical laughter of uncertain pathophysiology. A patient is presented with pathological laughter as the first manifestation of pontine ischaemia due t o vertebrobasilar stenosis. A 65 year old man developed uncontrollable and unemotional laughter for almost an hour followed by transient right facial- brachial paresis. He had fluctuation of laughter, right facial brachial par esis, and occasional crying. Magnetic resonance imaging, magnetic resonance angiogram (MRA), and an angiogram showed small left pontine and cerebellar infarcts, left vertebral artery occlusion, and right vertebral and basilar artery stenosis. His condition deteriorated to bilateral brain stem infarc tion and he died. Necropsy confirmed the extensive brain stem infarction. P athological laughter can be the very first presenting manifestation of isch aemia of the ventrotegmental junction of the upper pons. It is hypothesised that the pathological laughter in this patient was secondary to ischaemic ephaptic stimulation of the descending corticopontine/bulbar pathways.