Neurological manifestations in Japanese Ama divers.
Repetitive breath-hold (BH) diving can lead to accumulation of nitrogen (N2) in blood and tissues, which may give rise to decompression illness (DCI). An unusual condition is "Taravana", the diving syndrome reported by Cross in the 1960s. That report generated wide discussion as to whether BH diving can cause DCI. Paulev was the first person to suggest the link between DCI and BH diving. He, a submarine medical officer developed symptoms of DCI after a series of BH dives, having proceeded the dives by spending time in a hyperbaric chamber at 20 meters for 8 minutes. Recently four professional Japanese BH divers (Ama) with histories of diving accidents were reported. Magnetic resonance imaging of these divers detected cerebral infarcts localized in the watershed areas of the brain. A survey conducted on their island revealed that many Ama divers had experienced stroke-like events. A clinical feature of DCI in BH diving is that the damage is limited to the brain. Although the mechanisms of brain damage in BH diving are unclear, N2 bubbles passing through the lungs or the heart so as to become arterialized are most likely to be the etiological factor.
Kohshi
K
K
Department of Neurosurgery, University of Occupational and Environmental Health, Japan, Kitakyushu, Japan.
Wong
R M
RM
Abe
H
H
Katoh
T
T
Okudera
T
T
Mano
Y
Y
D000328:Adult; D002493:Central Nervous System Diseases / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy; D003665:Decompression Sickness / Q000209:etiology* / Q000628:therapy; D004242:Diving / Q000009:adverse effects*; D005260:Female; D006610:High Pressure Neurological Syndrome / Q000209:etiology; D006801:Humans; D006931:Hyperbaric Oxygenation / Q000379:methods; D007564:Japan; D008279:Magnetic Resonance Imaging; D008297:Male; D013366:Submarine Medicine; D013997:Time Factors