Low-tone perceptive hearing loss

Perilymph fistula: the Stanford experience

Seventy-eight tympanotomies were performed to determine the presence of perilymph fistulas (PLFs); of these, 51% were found. The oval and round windows of all patients were grafted, whether PLFs were present or not. Of those patients with PLFs, 64% had resolution of their major symptom; when no PLF was found, 44% had a similar outcome. We concluded that 1) PLFs often behave as if they are epiphenomena in relation to hearing and balance, 2) PLFs can be intermittent, 3) PLF surgery is disappointing for restoration of hearing in sudden hearing loss when compared to the rate of spontaneous recovery, 4) stabilizing a fluctuating or progressive loss is a more realistic goal, and 5) establishing preoperative criteria for exploration is still a problem.

Meniere's disease: a long-term follow-up study of hearing loss

Twenty patients suffering from Meniere's disease or Lermoyez syndrome were studied with respect to the time course of their hearing loss. Careful history-taking as well as repeated audiometry over long time spans (5-20 years) resulted in a longitudinal study of hearing loss at the standard audiometric frequencies. From these time series, correlation coefficients were computed between the changes in both ears at identical frequencies, and for changes in the same ear at different frequencies. Correlations between changes in hearing loss in both ears were more obvious in bilateral Meniere's disease than in unilateral disease. Correlations between changes in hearing loss at different frequencies were also more pronounced in Meniere's disease ears than in normal ears. If was found that recovery of hearing loss after an attack was nearly identical each time it occurred in the same ear, but differed between ears and patients. This deterministic finding in the otherwise random course of the hearing loss as a function of time may be important in deciding what mechanisms cause fluctuating hearing loss in Meniere's disease.