Audiometric Gelle test with a new transducer.

Abstract

The audiometric Gelle Test was administered to 10 young adults with normal hearing. Threshold measurements were obtained by air and bone conduction using ±40 cm H 2 O pressure at 250, 500, 750, and 1000 Hz. Positive and negative pressures were varied in steps of 10 cm H 2 O up to 50 cm H 2 O over the frequency range of 100–1000 Hz. This was done to determine the amount of pressure that produced the greatest temporary threshold shift. Results suggested: (1) pressures of ±30 cm H 2 O are satisfactory and optimal for clinical practice; (2) contrary to previous reports, low tones were not found to be more affected than moderately higher frequencies; (3) maximum shift occurs from 250–1000 Hz and reveals a uniform pressure effect over this frequency range; (4) negative pressures are more effective than positive; (5) air conduction is more affected than is bone conduction; (6) bone conduction evaluation continues to be fraught with many difficulties, most prominent being the occlusion effect; (7) an improved pressure transducer has been accomplished; and (8) test norms for air and bone conduction have been established.