Clinical characteristics and hearing recovery in perilymphatic fistulas of different etiologies.

Clinical features and hearing recovery were compared between three types of perilymphatic fistula groups; surgically confirmed (PLF-conf, n = 16), suspected (PLF-susp, n = 24) and traumatic (trauma-PLF, n = 11). Initial average hearing level was best in the PLF-susp group (50.9 dBHL), followed by the trauma-PLF (55.7 dBHL) and PLF-conf (59.7 dBHL) groups, though the difference was not significant (ANOVA, p > 0.05). Of 51 patients, 27 cases were operated on and fistula was confirmed in 19 ears (70.4%). Conservative treatment, including bed rest and medication, was given to all patients. After the treatment, meaningful hearing recovery was obtained only at 1 kHz in the PLF-conf group (paired t-test, p < 0.05). However, significant recovery was seen at all frequency ranges (0.125-8 kHz) in the PLF-susp group (average, 16.8 dB; p < 0.01), while hearing improvement was intermediate for the trauma-PLF group. The initial hearing level and the period until the start of treatment strongly correlated with the final hearing level. Although 27 patients (47%) complained of dizziness, the prognosis for vertigo is excellent as noted by other authors. It was concluded that if conservative treatment is started early for PLF patients with mild hearing loss, hearing recovery can be ensured.