The mechanisms underlying tinnitus are still not completely elucidated, but advances in neuroimaging and brain stimulation have provided us with new insights. Evidence suggests that tinnitus might actually be generated by central rather than peripheral structures. To illustrate the importance of brain activity changes in the pathology of tinnitus, we report the cases of 2 patients who experienced a recurrence/worsening of their tinnitus after they had undergone treatment for major depression with repetitive transcranial magnetic stimulation. We suggest that the tinnitus in these 2 patients was induced by changes in brain activity resulting from transcranial magnetic stimulation of the prefrontal cortex. We also review the pathophysiology and other aspects of tinnitus, focusing on associated brain reorganization.
We investigated the prognostic significance of the presence or absence of vertigo and tinnitus, the timing of the initiation of treatment, the type and severity of hearing loss, and age in 72 patients who had experienced sudden hearing loss. We found that the factors associated with a positive prognosis were the absence of vertigo, the presence of tinnitus, initiation of treatment within 7 days, a greater degree of hearing loss in the low frequencies, and a hearing loss of less than 45 dB. Age had no effect on prognosis.
Stapedotomy is primarily performed to treat hearing loss secondary to otospongiosis, although some patients find that the accompanying tinnitus is more bothersome than the hearing loss. We prospectively studied 23 consecutive patients with tinnitus secondary to otospongiosis who had undergone stapedotomy, and we compared their pre- and postoperative medical and audiologic findings. Patients' annoyance with their tinnitus was quantified by means of a visual analog scale, and their air-conduction thresholds were determined by measurements of a 4-frequency pure-tone average (0.5, 1, 2, and 4 kHz). Statistical analysis was performed using the paired Student's t test and Fisher's exact test. In the group as a whole, the mean tinnitus annoyance visual analog scores were 8.34 preoperatively and 1.56 postoperatively, a highly significant difference. Clinically, 22 of the 23 patients (95.7%) achieved satisfactory control of their tinnitus (improvement or complete resolution) following stapedotomy. With respect to hearing loss, all patients clinically improved postoperatively, and audiometry confirmed improvement at all 4 frequencies between 0.5 and 4 kHz. An air-bone gap of less than 10 dB was noted in 17 patients (73.9%). We conclude that in addition to improving hearing, stapedotomy also provides good control of tinnitus.