High-resolution intraoperative guide for cochlear implant surgery using optical coherence tomography

Area of Science:

• Otolaryngology
• Biomedical Engineering
• Surgical Technology

Background:

• Cochlear implantation (CI) surgery faces challenges with intra-cochlear trauma due to limited visualization, potentially impacting hearing outcomes.
• The round window membrane (RWM) approach, while less invasive, still carries risks of mechanical injury in the cochlea's complex anatomy.

Purpose of the Study:

• To evaluate the utility of intraoperative Optical Coherence Tomography (OCT) for real-time visualization during cochlear implantation.
• To assess OCT's potential in reducing intra-cochlear trauma and improving surgical precision.

Main Methods:

• Eight human temporal bones were used, with micro-CT scanning for baseline anatomy and OCT-micro-CT co-registration.
• A microscope-integrated OCT system visualized intra-cochlear structures through the RWM and an anteroinferior cochleostomy.
• Electrode insertions were guided by OCT, and feasibility was assessed under fluoroscopic control.

Main Results:

• Successful OCT imaging of the RWM and scala tympani (ST) was achieved, demonstrating its reliability for micro-anatomy evaluation.
• OCT provided crucial visualization for guiding electrode selection, approach, and insertion trajectory, supporting preoperative planning.
• The technology enhanced assessment of proximal cochlear anatomy, aiding in modification of the electrode array course.

Conclusions:

• Intraoperative OCT imaging significantly improves the precision of cochlear opening site and electrode insertion axis.
• Integrating OCT into CI surgery can transform it from a blind procedure to one with enhanced visual guidance.
• This approach promises to reduce surgical trauma and preserve postoperative hearing function.