[The predictive value of assessing mastoid pneumatization in pre-dive examinations].

Objectives: We investigated the value of assessing the degree of mastoid pneumatization in predicting middle ear barotrauma -the most common problem in sport SCUBA divers- in comparison with that of the conventional pre-dive examination method, the Valsalva maneuver.

Materials And Methods: Thirty-four volunteer sport SCUBA divers having normal pre-dive examination findings were included. The Valsalva test was performed in all the divers. Mastoid pneumatization for each ear was calculated on a Schuller's view radiography. Pneumatization of = or <30 cm2 was accepted as poor (prone to barotrauma) and >30 cm2 was accepted as good (not prone to barotrauma). During the observation period, the divers were monitored with regard to barotrauma symptoms and signs.

Results: The degree of mastoid pneumatization was = or <30 cm2 in 26 ears (38%) of 16 divers (47%). The Valsalva test was negative in eight ears (12%) of six divers (18%). During a total of 1001 dives, symptomatic middle ear barotrauma occurred in 28 dives (2.8%), i.e. in 21 ears (31%) of 16 divers (47%). Of these, the degree of mastoid pneumatization predicted barotrauma in 11 (69%) divers, whereas the Valsalva test was negative in only three (19%) (p<0.05), with sensitivity, specificity, positive and negative predictive values, and efficiency being 69% and 19%, 72% and 83%, 69% and 50%, 72% and 54%, and 71% and 53%, respectively.

Conclusion: The value of assessing mastoid pneumatization in predicting middle ear barotrauma in sport SCUBA divers is higher than that of the Valsalva test.