Ocular Compartment Syndrome and Lateral Canthotomy Procedure.

BACKGROUND: Ocular compartment syndrome (OCS) is a serious ophthalmological emergency that should be diagnosed and treated immediately to prevent permanent loss of vision. It is usually caused by a retro-orbital bleed that will subsequently increase intra-orbital pressure and threaten the patient's vision. Lateral canthotomy and cantholysis is a minor bedside procedure using simple equipment that is readily available in emergency departments, and the aim of such a procedure is to free the eye globe from its lateral attachment to the bony orbital wall and allow more eye protrusion and hence reduce intra-orbital pressure and save the patient's sight. The case we present describes a 42-year-old man who presented with facial injuries following an alleged assault and in whom a computed tomography scan of the head showed a retro-orbital hemorrhage. The patient had subtle signs of increased intra-orbital pressure for which lateral canthotomy and cantholysis was indicated. DISCUSSION: OCS is an ophthalmological emergency that can present with subtle signs of increased intraocular pressure that can lead to irreversible loss of vision if not treated with a simple bedside operation called lateral canthotomy and cantholysis within a specific time frame. We explore the pathophysiology and presentation of OCS and how to perform the lateral canthotomy with cantholysis procedure. CONCLUSIONS: The aim of this case presentation is to highlight the importance of diagnosing OCS as an ophthalmological emergency and discuss how to perform the sight-saving procedure.

Canthal cutdown for emergent treatment of orbital compartment syndrome.

This article evaluates the use of a "canthal cutdown" technique in orbital compartment syndrome in a cadaveric model. Twelve cadaver orbits were used to simulate orbital compartment syndrome using a blood analog solution. Two pressure probes, in different orbital locations, were used to monitor orbital pressure. Pressure was monitored during successive procedures: canthotomy, cantholysis, and canthal cutdown. Orbits were then re-injected with solution, simulating an active orbital hemorrhage, and pressure measurements were recorded over a 10-minute duration. No statistically significant difference was found between the two orbital pressure monitoring devices at each measurement point (p = 0.99). Significant pressure reductions, for both probes, were observed after canthal cutdown compared to initial measurement after injection of 20 mL blood analog (p < 0.001 and p = 0.005). When comparing the orbital pressure following canthotomy and inferior cantholysis versus canthal cutdown, the cutdown procedure provided an additional 74% in orbital pressure reduction (p =0.01). After re-injection of 10 mL of solution and 10 minutes of egress, pressure returned to baseline (probe 1: baseline 7 mm Hg vs. post-cutdown at 10 minutes 7 mm Hg; p = 0.83; and probe 2: 5 mm Hg vs. 5 mm Hg; p = 0.83). The canthal cutdown technique provides further reduction in orbital pressure versus canthotomy and cantholysis alone. The technique may be effective for treatment of static orbital compartment syndrome and temporizing treatment of compartment syndrome from active orbital hemorrhages.

Outcomes of medical and surgical management in eyes with idiopathic elevated episcleral venous pressure.

Purpose: Idiopathic elevated episcleral venous pressure (IEEVP) is a rare cause of secondary glaucoma and is a diagnosis of exclusion. The aim of this study was to describe the clinical presentation and analyze the outcomes of medical and surgical management in eyes diagnosed with idiopathic elevated episcleral venous pressure. Methods: A retrospective analysis of eyes diagnosed with IEEVP over a 5-year period between April 2012 and March 2016 was performed. The demographic details, medical history, and clinical course of the cases were obtained from the medical records. Data pertaining to the severity of glaucomatous damage, response to medical management, need for surgical intervention, and their outcomes were analyzed. Results: Fifteen eyes of 13 patients were included. Thirteen eyes (86.6%) had open angle configuration. Among the 13 eyes that had glaucoma, eight eyes (61.5%) had severe glaucoma, four eyes (30.7%) had moderate glaucoma, and one eye (7.6%) had mild glaucoma. The median follow-up was 210 days. Seven of the 15 eyes (46.6%) required a glaucoma filtration procedure, and three underwent prophylactic sclerotomies. 71.4% of these eyes had complete success. One out of the seven operated eyes required choroidal drainage post-operatively. Conclusion: IEEVP is an extremely rare condition and presents with raised intra-ocular pressure and tortuous episcleral vessels. The management of IEEVP is similar to that of primary open angle glaucoma. Uveal effusion is to be anticipated, and hence, combining trabeculectomy with prophylactic sclerotomies is advisable.

The Effect of Periocular Negative Pressure Application on Intraocular and Retrobulbar Pressure in Human Cadaver Eyes.

INTRODUCTION: To investigate the effect of applying negative pressure (vacuum) to the periocular space on intraocular pressure (IOP) and retrobulbar pressure (RBP) by use of the Multi-Pressure Dial (MPD) system (Equinox Ophthalmic, Inc.). METHODS: Two eyes of two full body cadavers were studied. In each subject, the retrobulbar space, posterior segment and intra-goggle space were cannulated to provide direct IOP, RBP and intra-goggle pressure measurements via a pressure transducer data acquisition system. The goggles of the MPD system were placed over the eyes of each subject, and multiple test runs were performed, with negative pressure settings programmed to 5, 10 and 20 mmHg. IOP and RBP measurements were continuously obtained during each run and plotted against time for analysis. RESULTS: For both subjects, the mean reduction (± standard deviation) in IOP was 1.6 ± 0.9 (10%), 3.5 ± 1.8 (23%) and 5.6 ± 2.0 (37%) mmHg at programmed negative pressure levels of - 5, - 10 and - 20 mmHg, respectively. The overall mean change in RBP (mmHg) during negative pressure application was 0.02 ± 0.14 at - 5 mmHg, 0.03 ± 0.19 at - 10 mmHg and - 0.01 ± 0.18 at - 20 mmHg. In both subjects, the magnitude of RBP change during application of negative pressure fell below the uncertainty of the measurement system. CONCLUSIONS: The application of negative pressure to the periocular space with the MPD decreases IOP but does not affect RBP.