Oval Window Temperature Changes in an Endoscopic Stapedectomy.

Area of Science:

• Otolaryngology
• Surgical Instrumentation
• Auditory Physiology

Background:

• Endoscopes are increasingly utilized in otologic procedures.
• Concerns exist regarding the thermal effects of endoscopic instruments.
• Temperature increase in the inner ear during surgery requires investigation.

Purpose of the Study:

• To investigate the temperature increase in the perilymph caused by endoscopes and light sources during a simulated stapedotomy.
• To evaluate the thermal impact of different light sources (halogen, LED, xenon) and endoscope diameters (3mm, 4mm) in an animal model.

Main Methods:

• A guinea pig model was used to simulate otologic stapes surgery.
• Temperature sensors were placed at the oval window to monitor perilymph temperature.
• Continuous temperature monitoring was performed during stapedotomy with various endoscopes and light sources.

Main Results:

• Rigid endoscopes, irrespective of diameter, caused a temperature increase in the tympanum when used with xenon and halogen light sources.
• LED light sources resulted in a comparatively smaller temperature increase.
• A measurable temperature increase was documented in the perilymph at the oval window.

Conclusions:

• Endoscopic instruments employed in stapes operations generate heat at the oval window.
• This heat can be transmitted to the cochlea via the perilymph.
• Potential for neurosensorial damage exists due to heat transmission to the cochlea.