Fig. 1: Electrophysiological effects of a locally applied AC102 hydrogel 24 h prior to cochlear implantation (CI) compared to a vehicle-treated control group.

a Normal auditory function was assessed 1 week prior to inclusion in the study by auditory brainstem responses (ABR). Twenty-four hours prior to cochlear implantation (Gel), a baseline compound action potential (CAP) measurement was carried out before the administration of 10 μL of the respective hydrogel via a retroauricular approach. On day 0 (CI), cochlear implantation was performed, and postoperative CAP and impedance measurements were carried out. Auditory function was assessed on days 0, 3, 7, 14 and 28 by CAP and impedance measurements. After the last experimental timepoint (End), animals were sacrificed, and their cochleae extracted for whole mount analysis. b–e CAP threshold shifts (dB) over the course of 28 days after cochlear implantation, treated with AC102 (n = 9, orange) or Vehicle hydrogel (n = 9, black) 24 h prior to implantation. Measured frequencies were grouped into (b) 0.5–1.5 kHz, (c) 2.0–5.0 kHz, (d) 6.3–12.6 kHz, and (e) 16–32 kHz. Error bars = SEM, *p < 0.05, **p < 0.01.