Round Window Membrane Visibility and its Implications in Cochlear Implant Surgery

Area of Science:

• Otolaryngology
• Neurosurgery
• Biomedical Engineering

Background:

• Increasing cochlear implant (CI) surgeries in patients with residual hearing necessitate less traumatic electrode insertion methods.
• The round window (RW) is a preferred insertion route to minimize intracochlear trauma.
• Round window membrane (RWM) visibility and orientation can challenge RW accessibility.

Purpose of the Study:

• To identify factors influencing the accessibility of the RW for electrode insertion.
• To evaluate the feasibility of RW electrode insertion in pediatric CI candidates.

Main Methods:

• Surgical assessment of RW membrane visibility and accessibility in 30 pediatric CI candidates.
• Standard posterior tympanotomy technique used for all procedures.
• RWM visibility graded from I to IV before niche drilling.

Main Results:

• RW insertion was successful in 66.7% of cases; extended RW in 33.3%.
• No cases required bony cochleostomy.
• No significant association found between RWM visibility grade and electrode insertion route.

Conclusions:

• RW insertion is achievable in most cases with normal cochlear anatomy.
• RWM visibility grades did not impact the electrode insertion route.
• Meticulous surgical technique, including careful bone removal in the RW niche, enhances visualization and insertion, making RW a viable, less traumatic option.