Vestibular effects of diving — a 6-year prospective study

Background Permanent injuries to the vestibular end organs may occur in diving due to decompression illness (DCI) or barotraumas. This may lead to distressing long-term symptoms, including dizziness and disequilibrium. Aims To look for evidence of vestibular disorders in working divers and to relate this to diving exposure or injuries. Methods A cohort of 67 men aged 28 ± 5 years (mean ± SD) completing a basic course for working divers answered a questionnaire and underwent clinical otoneurological examination, electronystagmography (ENG), including alternate bithermal caloric tests and platform posturography. The procedure was repeated after 3 and 6 years. Results At follow-up, none of the divers had experienced inner ear barotraumas or inner ear DCI. Two cases of untreated probable DCI were diagnosed retrospectively in 27 232 dives. Middle ear barotrauma was reported by 36%. There was no correlation between diving frequency and postural sway at follow-up. Transient dizziness during or shortly after a dive was reported by 63 and 15%, respectively. The prevalence of dizziness on land and ENG abnormalities did not change during follow-up. No vestibular disorders were diagnosed. Conclusions Transient vestibular symptoms and middle ear barotraumas are common in diving. This study found no evidence of long-term vestibular effects. Vestibular disorders in divers are probably related to singular events, like inner ear barotraumas or inner ear DCI, rather than frequent diving per se.