[Neurological decompression illness in a Japanese breath-held diver: a case report].

We report a Japanese breath-hold diver (Ama) who presented neurological disorders after diving. He repeated diving into 25-30 meters depth in the sea for 6 hours. After diving, he felt dizziness and unsteady gait. Neurological examination showed left quadrant hemianopia, bilateral limb ataxia and ataxic gait. Head CT revealed gas bubbles in the left parietal lobe. In CT scan on 3 days after onset, gas bubbles disappeared and low density areas were observed in the bilateral parietal lobes. Brain imaging (DWI, T(2)WI and FLAIR) demonstrated high intensity in the parieto-occipital lobes. Neither pulmonary barotrauma nor intracardiac shunt was detected. He was diagnosed as having neurological decompression illness and therefore underwent hyperbaric oxygen therapy. The pathogenesis of this case was considered to be microbubbles induced by decompression. The present case suggests that repetitive rapid surfacing from the deep sea causes neurological decompression illness even in the breath-hold diver.