Paracanthal “One-Snip” Decompression in a Cadaver Model of Retrobulbar Hemorrhage

Purpose: The authors assess the effectiveness of a modified paracanthal or "one-snip" procedure compared with the traditional lateral canthotomy and inferior cantholysis in the reduction of intraocular pressure (IOP) and proptosis in a human cadaveric model of retrobulbar hemorrhage. Methods: This study comprised a comparative interventional study in a cadaveric model of retrobulbar hemorrhage. Six orbits of 3 fresh cadavers were included in the study. Baseline measurements of IOP and proptosis were recorded for all 6 orbits before and after simulation of retrobulbar hemorrhage as previously described. Right orbits (n = 3) underwent traditional lateral canthotomy and inferior cantholysis. Left orbits (n = 3) underwent modified paracanthal or "one-snip" procedure. The primary outcome measures were reduction in IOP and proptosis between the 2 techniques. Results: Following lateral canthotomy and inferior cantholysis of each right orbit, the average IOP dropped to 14 mm Hg (range of 11–18 mm Hg), corresponding to a mean decrease of 32 mm Hg. Following the "one-snip" procedure of each left orbit, the average IOP dropped to 19 mm Hg with a range of 16 to 23 mm Hg, corresponding to a mean decrease of 22 mm Hg. There was no statistically significant difference in IOP reduction (p = 0.36) or proptosis reduction (p = 0.23) between the 2 treatment groups. Conclusions: Compared with traditional lateral canthotomy and inferior cantholysis, the modified paracanthal or "one-snip" procedure is effective for IOP reduction and led to mild improvement of proptosis in a cadaveric model of retrobulbar hemorrhage. The authors hope this study helps improve orbital compartment syndrome outcomes by providing an option that more providers will feel comfortable performing and therefore decreasing time to surgical decompression. Accepted for publication September 28, 2017. Supported in part by the NIH-NEI P30 Core Grant (IP30EY025585-01A1) and Unrestricted Grant from The Research to Prevent Blindness, Inc., awarded to the Cole Eye Institute. The authors have no conflicts of interest to disclose. Correspondence address and reprint requests to Alexander D. Blandford, M.D., Cole Eye Institute, Cleveland Clinic, 9500 Euclid Avenue, Desk i-13, Cleveland, OH 44195. E-mail: blandfa@ccf.org © 2018 by The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc., All rights reserved.