Orbital Compartment Syndrome After Pterional Craniotomy for Removal of Meningioma of the Frontal Lobe Without Evidence of Orbital Mass or Ocular Compression: A Case Report and Literature Review.

A 76-year-old male whose brain MRI demonstrated an anterior right frontal broad dural based homogenously enhancing mass measuring 6.0x3.1x6.3cm. after presenting with a one year progressive cognitive dysfunction. A right sided pterional craniotomy and resection of mass was performed under general anesthesia with an uncomplicated intraoperative course. Postoperatively, the right eye was noted to have an afferent pupillary defect, complete ophthalmoplegia, ptosis, and significant resistance to retropulsion. Emergent ophthalmologic consultation confirmed the ocular exam and the diagnosis of right orbital compartment syndrome was suspected. A right lateral canthotomy and cantholysis was performed by the ophthalmologist at the bedside. The fundoscopic retinal evaluation was normal. Non-contrast CT of the head demonstrated expected postoperative changes and mild edema of the right frontal lobe without evidence of acute hemorrhage. There was no retro-orbital hematoma but the right extra-ocular muscles appeared edematous compared to the left. No light perception and opthalmoplegia continued in the right eye. This case demonstrates that although very rare, orbital compartment syndrome can occur without compression of the eye or an intra-orbital mass. Visual loss is a devastating complication and preoperative informed consent of this complication is imperative. Constant vigilance to ensure adequate arterial and venous supply to the orbit, with great care to prevent external compression on the eye, hopefully, will continue to make this complication rare.