Endoscopic Endonasal Transethmoidal Supraorbital Approach for Orbitectomy Is a Viable Alternative

by Amy E. Hamaker •

What is the technique of the endoscopic endonasal transethmoidal supraorbital approach during an orbitectomy to the anterior cranial base?

Bottom Line: In the authors’ opinions, an endoscopic endonasal approach (EEA) plus superomedial orbitectomy represents a viable alternative for the resection of some intraorbital tumors with extension to the anterior cranial fossa, malignant sinonasal lesions with extension to the orbital roof, and some anterior cranial base tumors, including those that extend beyond the classic boundaries.

Background: The endoscopic endonasal transethmoidal approach extends from the frontal sinus to the planum sphenoidale and offers the most direct and immediate exposure of the anterior skull base without brain retraction and neurovascular structure manipulation. The limits of this approach are the medial wall of the orbit and the orbital contents.

Study Design: Thirty superomedial orbitectomies via EEA were completed in 15 fresh-frozen heads (all older than 18 years; 12 male, 3 female).

Setting: Department of Neurosurgery, University Hospital Virgen del Rocío, Seville, Spain.

Synopsis: Although good visualization was obtained, lateral extension beyond lamina papyracea was not achieved in zone 0 or sinusal zone. The maximum width of the endonasal superomedial orbitectomy (orbit to orbit) was at the interethmoidal zone, closely followed by the anterior ethmoidal zone. The widest individual segment, as measured from the midline, was the left interethmoidal zone, followed by the right anterior ethmoidal zone. The greatest distance from the lamina papyracea to the lateral edge of the orbitectomy was at the right interethmoidal zone, closely followed by the left interethmoidal zone. Maximal exposure was achieved near the midpoint between the ethmoidal arteries. After statistical analysis, we found that the distance from the midline to lateral edge of the orbitectomy in zone 1 or post-sinusal zone was significantly higher in the right orbit. The mean distance from the lamina papyracea to the free lateral edge of the orbitectomy in zone 4 or posterior ethmoidal zone was significantly higher in the left orbit. The lateral edge unions of all zones after performing the endoscopic osteotomies showed an asymmetrical “parenthesis” shape.

Citation: Ruiz-Valdepeñas EC, Kaen A, González-Martínez E, et al. Endoscopic endonasal superomedial orbitectomy: How far is safe and possible? Laryngoscope. 2020;130:1151-1157.