Transantral endoscopic orbital floor exploration: a cadaver and clinical study.

A cadaver and clinical study was performed to determine the value of transantral endoscopy in diagnosis and treatment of orbital floor fractures. Six fresh cadaver heads were dissected using a 30 degree, 4-mm endoscope through a 1 cm2 antrotomy. In the cadaver, the orbital floor and the course of the infraorbital nerve were easily identified. The infraorbital nerve serves as a reference point for evaluation of fracture size; three zones of the floor are described that are oriented relative to the infraorbital nerve. In the clinical study, nine patients with orbital floor fracture initially underwent endoscopy at the time of fracture repair: three patients had comminuted zygomatico-orbital fractures, five had monofragmented tetrapod fractures, and one had an isolated orbital blowout fracture. Endoscopic dissection of the orbital fractures revealed seven fractures with an area > 2 cm2 and two fractures with an area of < 2 cm2. The isolated orbital floor blowout fracture had entrapped periorbital tissue, which was completely reduced endoscopically. A separate patient with a < 2 cm2 displaced fracture also had stable endoscopic reduction. In the remaining seven patients, the endoscopic technique assisted with the floor reconstruction by identifying the precise fracture configuration as well as identifying the stable posterior ledge of the orbital floor fracture. There have been no complications in any of our patients to date. We conclude: (1) Transantral orbital floor exploration allows precise determination of orbital floor fracture size, location, and the presence of entrapped periorbita. The information obtained through endoscopic techniques may be used to select patients who would not benefit from lid approaches to the orbital floor and may possibly eliminate nontherapeutic exploration. (2) Transantral endoscopic orbital floor exploration assists the reduction of complex orbital floor fractures and allows precise identification of the posterior shelf for implant placement. (3) Transantral endoscopic techniques can completely reduce entrapped periorbital tissue caught in a trapdoor type of fracture.