Selection of an Endoscopic Endonasal or Transoral Approach to the Infratemporal Fossa

Both endonasal and transoral approaches can provide minimally invasive access to the infratemporal fossa (ITF); however, the appropriate indications for each corridor have not been sufficiently defined. This study aimed to explore the indication for selection of an endonasal or a transoral approach to the ITF.

Cadaveric dissection was performed on 6 specimens, one side for an endonasal approach and the contralateral side for a transoral approach. A complementary subdivision of the ITF into four quadrants (A-D) based on the crossing line at the lower border of the lateral pterygoid plate was established. Thirty-one patients who underwent endoscopic endonasal (Group 1) or transoral approach (Group 2) to remove tumors in the ITF were retrospectively reviewed. Related indices for each surgical approach were compared.

On cadaveric dissection, both the endonasal and the transoral approaches can provide access to the ITF. In Group 1, 26 patients underwent an endonasal approach, and the main tumor body was located at quadrant A. While patients in Group 2 performed a transoral resection, the tumor was mainly located in quadrant D. No significant difference for indices (e.g., operation length, morbidity) between groups (all p > 0.05), and no recurrence was detected.

The endonasal and transoral corridors are suitable for management of lesions at the medial and lateral or inferolateral aspects of the ITF, respectively. The relative tumor location to the lateral pterygoid plate may constitute an anatomic division tool to determine surgical approach selection.