A 60-year-old woman receiving an intraorbital injection for retrobulbar anaesthesia suddenly develops severe orbital pain, proptosis, subconjunctival chemosis, and a tight orbit with IOP measured at 48 mmHg. Vision drops to no perception of light. What is the most urgent immediate management?

• A Intravenous acetazolamide 500 mg
• B Anterior chamber paracentesis
• C Urgent CT orbit to confirm retrobulbar haemorrhage
• D Immediate lateral canthotomy and inferior cantholysis ✓

Explanation

This is acute orbital compartment syndrome from retrobulbar haemorrhage. Lateral canthotomy with inferior cantholysis rapidly decompresses the orbit and is sight-saving. It must be done within minutes. Intravenous acetazolamide and mannitol are adjuncts but do not replace surgical decompression. Imaging delays definitive treatment.

Reference: AAO BCSC Section 7: Orbit, Eyelids, and Lacrimal System, 2023-2024 ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.