Cerebral White-Matter Lesions in Asymptomatic Military Divers

Introduction: There is some concern that over a period of years, diving may produce cumulative neurological injury even in divers who have no history of decompression sickness. We evaluated asymptomatic divers and controls for cerebral white-matter lesions using magnetic resonance imaging (MRI). Methods: The study enrolled 113 male military divers (34.4 +/- 5.6 yr) and 65 non-diving men (33.1 +/- 9.0 yr) in good health. Exclusion criteria included any condition that might be expected to produce neurological effects. Patent foramen ovale was not assessed, A questionnaire was used to elicit diving history. A 1.5-T MRI device was used to acquire T1, T2-weighted, and fluid attenuated inversion recovery (FLAIR) images of the brain. A lesion was counted if it appealed hyperintense on both T2-weighted and FLAIR images. Results: MRI revealed brain lesions in 26 of 113 divers (23%) and in 7 of 65 (11%) controls, a difference that was Statistically significant. There was no significant difference between the groups with respect to blood pressure, smoking history, or alcohol consumption, and no subject reported a history of head trauma or migraine. There was no relationship between MRI findings and age, diving history, or lipid profile in divers. Discussion: The higher incidence of lesions in the, cerebral white matter of divers confirms the possibility that cumulative, subclinical injury to the neurological system rnay affect the long-term health of military and recreational divers.