FIG. 2.

Hearing outcomes of HB-EGF treatment of chronic tympanic membrane perforations. The ABR and DPOAE thresholds in decibels (db) during the study. At baseline, both the treatment and control ears are not significantly different. As would be predicted, the treatment ears show a hearing loss after creation of a chronic perforation. This hearing loss returns in the treatment ear after 2 months as measured by the ABR and within 2–6 months as measured by the DPOAE. At the 6-month measurement, there is no significant difference between the treated ears and the control ears. ABR, auditory brainstem response; DPOAE, distortion product otoacoustic emission.