Clinical evaluation of an image-guided cochlear implant programming strategy
Reviewed by Stephen James Broomfield

This study ingeniously combines two current areas of active research in cochlear implantation (CI), the first is the use of imaging to assess intra-cochlear electrode position. The second, is the optimisation of a programming strategy to prevent current spread between active electrodes resulting in loss of speech discrimination. In this study, pre- and postoperative CT imaging was used to assess the position of the implanted electrodes relative to the cochlear modiolus and spiral ganglion. Using the principle that electrodes will maximally stimulate the closest population of spiral ganglion cells, the authors predicted which frequencies each electrode would stimulate. Current spread was then reduced by switching off electrodes whose predicted regions of stimulation significantly overlapped (when two electrodes were found to stimulate the same frequency regions of the spiral ganglion, one of the electrodes was deactivated). This strategy was applied to 22 bilateral and 46 unilateral CI recipients with an average of 2.9 years of CI use and previously thought to have a stable and optimal CI map. Employing the programming strategy as described led to significantly improved speech recognition, spectral resolution and subjective hearing quality. As new imaging and programming techniques develop, it is likely that future research will increasingly examine techniques that allow for personalised programming strategies rather than a ‘one-size-fits-all’ approach.

Image-guided cochlear implantation programming.
Noble JH, Gifford RH, Hedley-Williams AJ, et al.
AUDIOLOGY NEUROTOLOGY
2014:19;400-11.