TRANSANTRAL ENDOSCOPIC ORBITAL FLOOR EXPLORATION - A CADAVER AND CLINICAL-STUDY

A cadaver and clinical study was performed to determine the value of t ransantral endoscopy in diagnosis and treatment of orbital floor fract ures. Six fresh cadaver heads were dissected using a 30 degree, 4-mm e ndoscope through a 1 cm(2) antrotomy. In the cadaver, the orbital floo r and the course of the infraorbital nerve were easily identified. The infraorbital nerve serves as a reference point for evaluation of frac ture size; three zones of the floor are described that are oriented re lative 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 orbita l fractures revealed seven fractures with an area >2 cm(2) and two fra ctures with an area of <2 cm(2). The isolated orbital floor blowout fr acture had entrapped periorbital tissue, which was completely reduced endoscopically. A separate patient with a <2 cm(2) displaced fracture also had stable endoscopic reduction. In the remaining seven patients, the endoscopic technique assisted with the floor reconstruction by id entifying the precise fracture configuration as well as identifying th e stable posterior ledge of the orbital floor fracture. There hale bee n no complications in any of our patients to date. We conclude: (1) Tr ansantral orbital floor exploration allows precise determination of or bital floor fracture size, location, and the presence of entrapped per iorbita. 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 exploratio n. (2) Transantral endoscopic orbital floor exploration assists in til e reduction of complex orbital floor fractures and allows precise iden tification of the posterior shelf for implant placement. (3) Transantr al endoscopic techniques can completely reduce entrapped periorbital t issue caught in a trapdoor type of fracture.