Exoscope-Assisted Middle Cranial Fossa Approach for Repair of Tegmental Defects: A Cadaveric and Clinical Study

Area of Science:

• Neurosurgery
• Surgical Technology
• Skull Base Surgery

Background:

• Exoscopes are increasingly used for lateral skull base approaches.
• Middle cranial fossa (MCF) defect repair using exoscopes remains underexplored.
• Surgical microscopes have limitations in MCF surgery, including physical obstruction.

Purpose of the Study:

• To present a proof of concept for exoscope-assisted surgery in repairing middle cranial fossa defects.
• To evaluate the feasibility and effectiveness of exoscopes in MCF defect repair.

Main Methods:

• A step-by-step MCF approach was performed on two cadaveric specimens using exoscopic magnification.
• An illustrative clinical case of an encephalocele secondary to a spontaneous tegmen tympani defect was presented.
• The exoscope-assisted technique was utilized for defect localization, resection, and repair.

Main Results:

• Exoscopic magnification allowed successful exposure of common MCF defect sites (tegmen tympani, arcuate eminence).
• Dissection was performed without damaging critical neurovascular structures or the dura mater.
• The clinical case demonstrated adequate maneuverability, magnification, and comfortable surgeon positioning with no prolonged operative time.

Conclusions:

• Exoscopes provide adequate exposure of the MCF floor, facilitating identification and preservation of key anatomical structures.
• Exoscope-assisted surgery is a valuable alternative to traditional microscopy for MCF defect reconstruction.
• The technique offers high-quality magnification and proven maneuverability for complex skull base procedures.