Computed Tomography–Based Measurements of the Cochlear Duct: Implications for Cochlear Implant Pitch Tuning

Objectives:

To determine the sources of variability for cochlear duct length (CDL) measurements for the purposes of fine-tuning cochlear implants (CI) and to propose a set of standardized landmarks for computed tomography (CT) pitch mapping.

Design:

This was a retrospective cohort study involving 21 CI users at a tertiary referral center. The intervention involved flat-panel CT image acquisition and secondary reconstructions of CIs in vivo. The main outcome measures were CDL measurements, CI electrode localization measurements, and frequency calculations.

Results:

Direct CT-based measurements of CI and intracochlear landmarks are methodologically valid, with a percentage of error of 1.0% ± 0.9%. Round window (RW) position markers (anterior edge, center, or posterior edge) and bony canal wall localization markers (medial edge, duct center, or lateral edge) significantly impact CDL calculations [F(2, 78) = 9.9, p

Source: Ear and Hearing - May 1, 2021 Category: Audiology Tags: Research Article Source Type: research