Acute Monocular Blindness Due to Orbital Compartment Syndrome Following Pterional Craniotomy

We present a case of orbital compartment syndrome (OCS) leading to monocular irreversible blindness following a pterional craniotomy for clipping of an anterior communicating artery aneurysm. OCS is an uncommon but vision-threatening entity requiring urgent decompression to reduce the risk of permanent visual loss. Iatrogenic orbital roof defects are a common finding following pterional craniotomies. However, complications related to these defects are rarely reported.

A 65-year-old female who underwent an anterior communicating artery clipping via a pterional approach 4 days before developed proptosis, ocular movement paresis, and irreversible visual impairment following an orthopedic surgery. Computed tomography images revealed an intraorbital cerebrospinal fluid (CSF) collection, which was evacuated via an acute recraniotomy. The next day, proptosis and intraorbital CSF collection on computed tomography images reoccurred and an oral and maxillofacial surgeon evacuated the collection via a blepharoplasty incision and blunt dissection. In addition, the patient was treated with acetazolamide and an external lumbar CSF drainage during 12 days. Hereafter, the CSF collection did not reoccur. Unfortunately, monocular blindness was persistent. We hypothesize the CSF collection occurred due to the combination of a postoperative orbital roof defect and a temporarily increased intracranial pressure during the orthopedic surgery.

We plead for more awareness of this severe complication after pterional surgeries and emphasize the importance of 1) strict ophthalmologic examination after pterional craniotomies in case of intracranial pressure increasing events, 2) immediate consultation of an oral and maxillofacial surgeon, and 3) consideration of CSF-draining interventions since symptoms are severely invalidating and irreversible within a couple of hours.