Emergent Management of Orbital Compartment Syndrome
Orbital compartment syndrome (OCS) is a true ophthalmic surgical emergency requiring immediate lateral canthotomy with inferior cantholysis (LCIC) at the bedside—even before imaging—to prevent irreversible blindness. 1, 2
Immediate Bedside Intervention
Perform lateral canthotomy with inferior cantholysis immediately when OCS is clinically diagnosed. 1, 2, 3 The diagnosis is entirely clinical and does not require imaging confirmation before treatment. 2 Better visual outcomes are achieved when intervention occurs within the first 2 hours of symptom onset. 3
Clinical Diagnosis
Recognize OCS by the following findings:
- Acute vision loss or rapidly declining visual acuity 1, 2
- Afferent pupillary defect (Marcus Gunn pupil) 1, 4
- Proptosis with resistance to retropulsion (firm, tense globe) 1, 4
- Ophthalmoplegia (limitation or complete loss of extraocular movements) 1, 4
- Elevated intraocular pressure (often >40 mmHg) 1, 2
- Tense, edematous eyelids 2, 5
Lateral Canthotomy with Inferior Cantholysis Technique
The emergency physician must be trained to perform this procedure: 1
- Clamp the lateral canthus with a hemostat for 1-2 minutes to achieve hemostasis 1
- Make a horizontal incision through the full thickness of the lateral canthus extending approximately 1-2 cm 1
- Identify and completely divide the inferior canthal tendon by pulling the lower eyelid away from the globe and cutting inferiorly until the tendon releases with an audible "pop" 1
- Ensure complete division—incomplete cantholysis is a common pitfall that fails to adequately decompress the orbit 1
Additional Decompressive Measures
If LCIC alone does not restore vision or reduce intraocular pressure:
- Incise the orbital septum to allow further decompression 2
- Consider bony orbital decompression in unresponsive cases, though this typically requires ophthalmology or oculoplastic surgery 2, 3
- Treat the underlying cause (evacuate hematoma, drain abscess, address infection) 3, 5
Critical Management Pitfalls to Avoid
Never delay treatment to obtain imaging—CT or MRI should not precede bedside decompression when clinical diagnosis is clear. 1, 2 Imaging can be obtained after initial decompression to identify the underlying cause. 1
Never fail to exclude globe rupture before performing LCIC—if globe rupture is suspected, protect the eye and obtain urgent ophthalmology consultation before manipulation. 1
Never rely on the presence of a retrobulbar hematoma on imaging—OCS can occur without visible orbital mass or hemorrhage due to orbital edema and venous congestion alone. 4
Never assume delayed presentation precludes intervention—although outcomes are best within 2 hours, there are reports of visual recovery even with delayed management, and decompression should still be attempted. 3
Never fail to decrease intraocular pressure medically while preparing for LCIC—administer topical beta-blockers, alpha-agonists, and intravenous acetazolamide or mannitol if available. 1
Post-Decompression Management
- Obtain immediate ophthalmology consultation for definitive management and identification of underlying cause 1, 3
- Document the complete physical examination thoroughly, including visual acuity, pupillary response, extraocular movements, intraocular pressure, and fundoscopic findings before and after intervention 1
- Perform fundoscopic examination to assess for central retinal artery occlusion or optic nerve damage 4
- Obtain imaging after decompression to identify retrobulbar hematoma, orbital fracture, infection, or other underlying pathology 1, 3
Prognosis
Visual outcomes depend critically on time to decompression. 3 Irreversible blindness occurs when treatment is delayed beyond 90-120 minutes in most cases. 2, 3 Even with prompt intervention, permanent vision loss can occur, making this a devastating complication requiring constant vigilance. 4, 5