Combined Electric and Acoustic Stimulation With Hearing Preservation: Effect of Cochlear Implant Low-Frequency Cutoff on Speech Understanding and Perceived Listening Difficulty.

Only 11 participants (13 ears) were tested, and participant 4 was excluded from averaged analyses because of electrode tip fold-over, so the sample is small. All participants had standard-length conventional electrodes, not hybrid or electric-acoustic stimulation electrodes, so findings may not apply to shorter hybrid electrodes. All participants had aidable acoustic hearing in both ears, so findings may not apply to patients with electric-acoustic stimulation in one ear without acoustic hearing in the other. The testing used restaurant noise and specific speech materials, and the speech and noise spectra were not perfectly matched, so results may not generalize to other noise types or talkers. Noise reduction was enabled in all programs, so results may not apply to patients programmed without noise reduction. Acute and chronic testing was checked in only 3 participants (5 ears), so longer-term adaptation to cutoff changes is uncertain. For adaptive thresholds, values above +5 dB signal-to-noise ratio were affected by processor saturation, so those results should be interpreted cautiously.

Do not choose the low-frequency cutoff from patient preference alone. Five of the 13 ears had poorer speech understanding at their preferred cutoff than at their best cutoff.