TY - JOUR
T1 - Electrical Impedance as a Biomarker for Inner Ear Pathology Following Lateral Wall and Peri-modiolar Cochlear Implantation
AU - Shaul, Chanan
AU - Bester, Christofer W.
AU - Weder, Stefan
AU - Choi, June
AU - Eastwood, Hayden
AU - Padmavathi, K. V.
AU - Collins, Aaron
AU - O'Leary, Stephen J.
N1 - Funding Information:
S.J.O. is funded by the National Health and Medical Research Council (Australia). This research was conducted at the Royal Victorian Eye and Ear Hospital and funded by the National Health and Medical Research Council (Australia). The authors disclose no conflicts of interest.
Publisher Copyright:
© 2019, Otology & Neurotology, Inc.
PY - 2019/6/1
Y1 - 2019/6/1
N2 - Objectives/Hypothesis: Spikes in cochlear implant impedance are associated with inner ear pathology after implantation. Here, we correlate these spikes with episodes of hearing loss and/or vertigo, with a comparison between lateral wall and peri-modiolar electrode arrays. Methods: Seven hundred seventy recipients of Cochlear's slim-straight, lateral wall electrode (CI422), or peri-modiolar (CI512) electrode were investigated for impedance spikes. Impedance fluctuations were defined as a median rise of ≥ 4 kV across all intracochlear electrodes from baseline measurements taken 2 weeks after switch-on. Medical records were analyzed from 189 of the 770 patients. Results: The slim straight, lateral wall electrode was found to spike in impedance at a significantly higher rate than the peri-modiolar array (17% vs 12%). The peri-modiolar electrode tended to spike in impedance earlier than the slimstraight electrode. Impedance spikes were found to significantly correlate with medical events (hearing loss, vertigo, or tinnitus). Overall, in the "spike"group, 42 of 75 patients (56%) demonstrated a clinical event during the impedance spike, whereas 26 of 114 patients (22%) of the "non-spike"group had a clinical event. This significant difference existed with both implant types. Conclusion: These results demonstrate a small, but significant increase in impedance spikes in lateral wall electrodes, and support the relationship between spikes in cochlear implant impedances and postoperative inner-ear events, including the loss of residual hearing and vertigo. Monitoring cochlear implant impedance may be a method for early detection, and so the prevention, of these events in the future.
AB - Objectives/Hypothesis: Spikes in cochlear implant impedance are associated with inner ear pathology after implantation. Here, we correlate these spikes with episodes of hearing loss and/or vertigo, with a comparison between lateral wall and peri-modiolar electrode arrays. Methods: Seven hundred seventy recipients of Cochlear's slim-straight, lateral wall electrode (CI422), or peri-modiolar (CI512) electrode were investigated for impedance spikes. Impedance fluctuations were defined as a median rise of ≥ 4 kV across all intracochlear electrodes from baseline measurements taken 2 weeks after switch-on. Medical records were analyzed from 189 of the 770 patients. Results: The slim straight, lateral wall electrode was found to spike in impedance at a significantly higher rate than the peri-modiolar array (17% vs 12%). The peri-modiolar electrode tended to spike in impedance earlier than the slimstraight electrode. Impedance spikes were found to significantly correlate with medical events (hearing loss, vertigo, or tinnitus). Overall, in the "spike"group, 42 of 75 patients (56%) demonstrated a clinical event during the impedance spike, whereas 26 of 114 patients (22%) of the "non-spike"group had a clinical event. This significant difference existed with both implant types. Conclusion: These results demonstrate a small, but significant increase in impedance spikes in lateral wall electrodes, and support the relationship between spikes in cochlear implant impedances and postoperative inner-ear events, including the loss of residual hearing and vertigo. Monitoring cochlear implant impedance may be a method for early detection, and so the prevention, of these events in the future.
KW - Biomarkers
KW - Cochlear implant
KW - Hearing loss
KW - Impedance
UR - http://www.scopus.com/inward/record.url?scp=85066061718&partnerID=8YFLogxK
U2 - 10.1097/MAO.0000000000002227
DO - 10.1097/MAO.0000000000002227
M3 - Article
C2 - 31083087
AN - SCOPUS:85066061718
SN - 1531-7129
VL - 40
SP - E518-E526
JO - Otology and Neurotology
JF - Otology and Neurotology
IS - 5
ER -