Abstract
Insidious development of high-tone sensorineural hearing loss may be associated with diving, but the evidence is not certain and further research is needed. 'Internal ear barotrauma' can cause an acute or relatively acute onset of hearing loss and/or vertigo, and it may be that 'alternobaric vertigo' provides a link between the insidious and acute forms of labyrinthine injury in diving. With deep diving, decompression sickness and other syndromes can also affect the cochleo-vestibular system. These aetiologies and effects will be discussed, together with evidence from an audiometric survey of naval divers and of 5 experimental deep divers