We report two Japanese male professional breath-hold divers (33 and 39 years of age) who experienced neurological disorders during repetitive dives to over 20 m of seawater. One patient had right homonymous hemianopsia, and the other presented with right hemiparesis with facial involvement and sensory deficit. In addition, they each had a history of neurological problems following such dives. Magnetic resonance images of their brains disclosed multiple T2-weighted hyperintensities corresponding to their neurological symptoms. Their brain lesions suggest a multiple cerebral infarction caused by occlusion of the cerebral arteries. We conclude that the repetitive deep breath-hold dives induced the brain involvement.

Kohshi, Katoh, Abe, Okudera (2000). Neurological accidents caused by repetitive breath-hold dives: two case reports. Journal of the neurological sciences, 2000 Sep;178(1):66-9. https://www.ncbi.nlm.nih.gov/pubmed/11018252