Inner ear barotrauma after stapedectomy in the guinea pig.

OBJECTIVE

The safety of scuba diving after stapedectomy is controversial. Stapedectomy is thought to predispose to inner ear barotrauma (e.g., perilymph fistula); however, many individuals continue to scuba dive following stapedectomy without ill effects. The purpose of this study was to evaluate the cochlear effects of barotrauma, similar to that experienced with scuba diving, on inner ears previously treated with stapedectomy.

STUDY

DESIGN

Prospective, controlled.

METHODS

Sixteen Hartley albino guinea pigs underwent unilateral total stapedectomy followed by hyperbaric dives on 5 consecutive days, beginning 3 weeks after stapedectomy. Cochlear effects were determined using click and tone-pip evoked electrocochleographic thresholds and cochlear hair cell counts.

RESULTS

Mean auditory thresholds increased by 29 dB after stapedectomy (P < .001), then remained stable thereafter. Mean thresholds in both the operated and control ears did not change with hyperbaric dives. Evidence of middle ear barotrauma (e.g., hemorrhage or tympanic membrane perforation) was observed in eight poststapedectomy ears and five control ears, but none demonstrated significant threshold elevation greater than or equal to 10 dB. Hair cell counts were not different between operated and control ears.

CONCLUSIONS

Stapedectomy does not appear to predispose to cochlear sequelae in the guinea pig model of diving-related barotrauma.