FIG. 11.

Cochlear sensitivity changes measured during 60 min injections of artificial perilymph (Control, n = 3), of fluorescein (n = 8) or of mDex (n = 9) at the concentrations used in the kinetic studies. Sensitivity was assessed by CAP thresholds at the 4 frequencies indicated using an automated procedure with a criterion of 10 μV. Measurements were made at 2 min intervals but SD error bars are only shown at 20 min intervals for clarity. Threshold changes produced by mDex were almost identical to those induced by control injections. Fluorescein caused substantial elevations of CAP thresholds.