Utilizzo del TEN test per lo studio delle regioni cocleari morte

Recent work using the Threshold Equalizing Noise (TEN) test as a gold standard suggests that the presence of cochlear dead regions ( non –functioning, silent regions) in persons with moderate-tosevere hearing loss may be quite common. In addition, previous data suggest that certain characteristics of hearing loss, such as severe-profound high-frequency hearing loss may be more commonly associated with positive TEN findings. These findings, however, are based largely on studies including a relatively small number of participants or participants that were included based on specific audiometric criteria. There has been less work that has systematically evaluated the relationship between audiometric characteristics and TEN test findings, on a large number of individuals with a wide range of hearing losses and hearing loss configurations. Purpose The purpose of this study was to further examine the effects of audiometric characteristics such as degree of the hearing loss on the rate of positive, negative, and inconclusive findings on the TEN test over a wide frequency range (500-400 Hz) using a new HL calibrated version of TEN test. Given that the functional impact of positive findings may vary with the extent of potential damage, we were also interested in determining the relative occurrence of “patchy” versus multiple positive findings on the TEN. Research Design Twenty - eight persons (56 ears) with a wide range of SNHL participated. To discover the presence of d.c.r. the TEN (HL), was utilized. Thresholds, in both ears, were measured in quiet and in the TEN (HL). Results were categorized as positive (suggestive of a dead region), negative (not suggestive of a dead region), or inconclusive. Results Consistent with past research, positive TEN (HL) results were more common when hearing losses exceeded 60 dB HL; however, there was not a systematic increase in positive results with increases in threshold. In contrast to previous work, however, positive test results among individuals with milder hearing losses (<60 dB HL) were not uncommon, suggesting a potential for false positive results. Although a large proportion of participants had positive results on the TEN (HL), for most participants, these positive findings occurred in isolated (i.e., one frequency) rather than in multiple frequency regions. Conclusions The presence of inconclusive results and the potential for false positive results makes interpreting the functional impact of TEN (HL) results difficult, particularly when positive results are in the high frequencies or affect with frequencies with low to moderate hearing loss. In addition, although a large proportion of study participants had positive findings on the TEN (HL), the functional impact of these findings is not clear as, in the majority of cases, positive findings occurred at only one or two test frequencies.