Threshold sound conditioning in the treatment of sensorineural hearing loss.

OBJECTIVES/HYPOTHESIS: Sensorineural hearing loss is one of the most common human disorders, with increasing incidence in elderly patients, severely restricting normal activities, and lowering quality of life. The introduction of sound conditioning has the potential to activate auditory pathway plasticity and improve basal frequency hearing. Our objective was to evaluate the safety and efficacy of threshold sound conditioning (TSC). The null hypothesis in this study was that TSC does not have a significant effect on auditory threshold amelioration.

METHODS

Pure tone audiometry (PTA) was performed and hearing thresholds were measured once at baseline, and a second time following TSC intervention. Data were analyzed using an intention-to treat design.

RESULTS

The TSC group (78%) significantly differed from the control group (44%) on auditory threshold amelioration; = .008091 in DV1, = .000546 in DV2 by Scheffe's post hoc test. Female subjects (77%) showed a significant difference in DV1 from male subjects (47%); = .025468 in DV1 by Scheffe's post hoc test. Older subjects (75%) showed no significant difference from younger subjects (53%); = .139149 in DV1, = .082920 in DV2 by Scheffe's post hoc test.

CONCLUSIONS

We observed a significant improvement in a narrow band frequency threshold in this randomized controlled prospective clinical study in a broad range of subjects. These data have important clinical implications since there is no current long-term therapy for this widespread and growing disability. Additional physiologic, mechanistic, and molecular studies are necessary to fully elucidate the pathophysiology and mechanism of action of TSC.

LEVEL OF EVIDENCE

1a.