Endoscopic Endonasal Approach and Endoscopic Supraorbital Keyhole Approach to the Sellar Tubercle Region—Alternative or Combinatory Approaches: Anatomic Study for Surgical Freedom

Background: The endoscopic endonasal approach and the supraorbital keyhole approach are the minimally invasive accesses to the sellar tubercle region. The exposures of the operative field are often compared. However, no anatomic study has examined the operative maneuverability of both approaches. We compare the surgical freedom to determine which approach provides a superior operative maneuverability.

Methods: Five neurovascular injected cadaver heads were used for the study. The endoscopic endonasal approach to the sellar tubercle region was performed on five heads, and the endoscopic supraorbital keyhole approach was done on the both sides of the five heads receiving EEA. Surgical freedom was determined with stereotactic image guidance. Six points were selected: leading edge of sphenoid sinus, the edge of dorsum sellae, ipsilateral and contralateral medial OCR, ipsilateral and contralateral lateral OCR. The results are presented as angular surgical freedom in the axial and sagittal planes and the area of surgical freedom of each points.

Results: The endoscopic supraorbital keyhole approach provided superior surgical freedom on the point of the ipsilateral lateral OCR. The endoscopic endonasal approach provided superior surgical freedom on the rest points. The combination of the both approaches provided complementary of surgical freedom.

Conclusion: The endoscopic endonasal approach is suitable for the tumors located in the midline area (between bilateral OCRs). The endoscopic supraorbital keyhole approach is suitable for the tumors located in the lateral area (lateral extension of the ipsilateral lateral OCR). The combination of the both approaches can provide best surgical maneuverability, which is suitable for the giant lesion of the sellar tubercle region.

Fig. 1 The surgical freedom of the endoscopic endonasal approach and the supraorbital keyhole approach.

Fig. 2 Operative images of the combination of the endoscopic endonasal approach and the supraorbital keyhole approach.