Imaging cochlear implantation with round window insertion in human temporal bones and cochlear morphological...

Area of Science:

• Otorhinolaryngology
• Medical Imaging
• Neurosurgery

Background:

• Cochlear implant (CI) surgery requires precise placement of electrode arrays within the cochlea.
• Accurate visualization of intracochlear structures and electrode position is crucial for successful CI outcomes.
• Existing imaging modalities may have limitations in depicting fine details of the cochlea and electrode placement.

Purpose of the Study:

• To assess a novel cone-beam computed tomography (CBCT) system for its ability to define cochlear implant (CI) electrode arrays.
• To evaluate the system's capacity in characterizing morphological variations of the human cochlea.
• To determine the spatial resolution and accuracy of CBCT in visualizing intracochlear anatomy.

Main Methods:

• Human temporal bones were implanted with three types of electrode arrays (standard, Flex28, experimental 36-contact) via atraumatic round window insertion.
• High spatial resolution CBCT imaging was performed using a specialized setup with a Superior SXR 130-15-0.5 X-ray tube and copper-aluminum filtration.
• 900 frames were acquired per cochlea to capture detailed anatomical and electrode information.

Main Results:

• Key cochlear landmarks, including the modiolus, osseous spiral lamina, round window niche, and stapes, were clearly visualized.
• Electrode array contacts were accurately depicted within the scala tympani in all specimens.
• A significant linear correlation was found between the 'A' value and cochlear height, as well as insertion length for the initial 360° depth.

Conclusions:

• The high spatial resolution CBCT system effectively demonstrates critical cochlear landmarks.
• This CBCT setup accurately identifies the position of intracochlear electrode contacts.
• The technology holds promise for clinical application in enhancing cochlear implant surgery precision.