Post-Operative Delirium Masking Acute Angle Closure Glaucoma

Introduction: Acute angle closure glaucoma (AACG) is an ophthalmological emergency, and can lead to the devastating consequence of permanent vision loss if not detected and treated promptly. We present a case of an atypical presentation of unilateral AACG on post operative day (POD) 1, after a prolonged operation under general anaesthesia (GA).
Case presentation: A 65-year-old female underwent a 16 hour long operation for breast cancer and developed an altered mental status with a left fixed dilated pupil on POD 1. She was intubated to secure her airway in view of a depressed consciousness level and admitted to the intensive care unit. Initial blood investigations and brain imaging were unremarkable. On subsequent review by the ophthalmologist, a raised intraocular pressure was noted and she was diagnosed with acute angle closure glaucoma. She was promptly started on intravenous acetazolamide and pressure-lowering ophthalmic drops. Her intraocular pressure normalized in the next 24 hours with improvement in her mental status to baseline.
Conclusion: AACG needs to be consistently thought of as one of the top differentials in any post-operative patient with eye discomfort or abnormal ocular signs on examination. A referral to the ophthalmologist should be made promptly once AACG is suspected.