Access to the medial orbit traditionally has been gained transcutaneously, with potential for associated soft tissue and lacrimal disruption. Endoscopic transnasal approaches to the medial orbit may be limited in certain scenarios by tumor presence or patient-specific factors. The medial transconjunctival approach, or transcaruncular approach, has been recently described for access to the medial orbit in orbital decompression and repair of medial blowout fractures. The aim of this study is to determine the utility of this minimally invasive external approach in the endoscopic management of advanced sino-orbital disease.
This is a cadaver study with additional clinical correlations. The transcaruncular approach was combined with a transnasal endoscopic approach in cadaver dissections performed on eight sides. Five cases are described in which the transcaruncular approach was used as an adjunctive technique in advanced endoscopic sinus surgery.
In cadaver dissection, the transcaruncular approach is a simple, reliable method to ligate the ethmoid arteries and place bony cuts along the medial orbital wall. In certain anatomic configurations, supraorbital dissection into the frontal sinus or anterior fossa may be achieved. In the cases examined, exposure of the medial orbital subperiosteal plane allowed for ligation of ethmoid arteries, assessment of periorbital invasion of disease, assistance in tumor dissection, and placement of a malleable retractor for protection of orbital contents.
The transcaruncular approach to the medial orbit has certain advantages over the traditional open approach. Ligation of the ethmoid arteries, assessment of the lacrimal sac and periorbita for tumor invasion, protection of orbital contents, and en bloc resection of the periorbita and lamina papyrecea are possible through this route.