Cochlear implants (CIs) are surgically implanted neural prosthetic devices used to treat severe-to-profound hearing loss. Our group has developed Image-Guided Cochlear Implant Programming (IGCIP) techniques to assist audiologists with the configuration of the implanted CI electrodes. CI programming is sensitive to the spatial relationship between the electrodes and intra cochlear anatomy (ICA) structures. We have developed algorithms that permit determining the position of the electrodes relative to the ICA structure using pre- and post-implantation CT image pairs. However, these do not extend to CI recipients for whom pre-implantation CT (Pre-CT) images are not available because post-implantation CT (Post-CT) images are affected by strong artifacts introduced by the metallic implant. Recently, we proposed an approach that uses conditional generative adversarial nets (cGANs) to synthesize Pre-CT images from Post-CT images. This permits to use algorithms designed to segment Pre-CT images even when these are not available. We have shown that it substantially and significantly improves the results obtained with our previous published methods that segment post- CT images directly. Here we evaluate the effect of this new approach on the final output of our IGCIP techniques, which is the configuration of the CI electrodes, by comparing configurations of the CI electrodes obtained using the real and the synthetic Pre-CT images. In 22/87 cases synthetic image lead to the same results as the real images. Because more than one configuration may lead to equivalent neural stimulation patterns, visual assessment of solutions is required to compare those that differ. This study is ongoing.
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