Visual outcomes after traumatic retrobulbar hemorrhage are not related to time or intraocular pressure

• Published in: The American journal of emergency medicine Vol. 38; no. 11; pp. 2308 - 2312
• Main Authors: Dixon, Jessica L., Beams, Owen K., Levine, Brian J., Papas, Mia A., Passarello, Brent A.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-11-2020; Elsevier Limited
• Subjects: Acuity; Blindness - prevention & control; Canthotomy; Compartment syndrome; Compartment Syndromes - etiology; Decompression, Surgical - methods; Emergency medical care; Emergency medical services; Emergency Service, Hospital; Female; Hemorrhage; Humans; Injuries; Intraocular; Intraocular Pressure; Male; Middle Aged; Ophthalmology; Optic nerve; Patients; Population studies; Retrobulbar; Retrobulbar Hemorrhage - etiology; Retrobulbar Hemorrhage - surgery; Retrospective Studies; Time Factors; Trauma; Visual Acuity; Wounds and Injuries - complications; Ophthalmology; Intraocular; Retrobulbar; Canthotomy
• ISSN: 0735-6757; 1532-8171
• DOI: 10.1016/j.ajem.2019.10.024

The paucity of literature regarding the role of time and intraocular pressure (IOP) when treating ocular compartment syndrome (OCS) has resulted in limited guidance for emergency physicians (EP).
Our goals were to investigate the ideal time frame for lateral canthotomy, to understand the relationship between IOP and visual outcome, and to determine the impact of EP performance on visual acuity (VA).
The study population included patients presenting over an 18-year period with traumatic retrobulbar hemorrhage (RBH) treated with lateral canthotomy. Efficacy was evaluated using visual outcome and IOP. Patients were grouped by time from injury and arrival to canthotomy. Procedures completed in the emergency department (ED) and by EPs were evaluated regarding visual outcome.
Sixty cases of RBH treated with lateral canthotomy were identified. Over two-thirds (43/60, 71.7%) were discharged with baseline vision. Lateral canthotomy lowered IOP from a median of 50.0 mmHg (IQR: 40.5, 61) preprocedure to 23.0 mmHg (IQR: 18, 27) post-procedure (p-value = 0.000001). No correlation was found between time, IOP, location, specialty of clinician, and visual outcome.
Lateral canthotomy is an effective at lowering IOP. Our data suggest that using time and IOP to predict procedural outcome is flawed. If OCS is suspected, lateral canthotomy should be considered and can be effectively performed by EPs. Neither the time of injury to ED presentation nor degree of IOP elevation should be factored into the decision of when to perform the procedure.