A 54-year-old man, suffering from severe headache and ophthalmoplegia after undergoing endoscopic sinus surgery was referred to a tertiary hospital. Computed tomography (CT) revealed soft tissue density lesions in the left sphenoid sinus. The internal carotid artery was shown to be occluded in brain magnetic resonance imaging (MRI) scans without any other cerebral lesion.

Endoscopic view of left nasal cavity shows whitish hyphae in the ethmoid and the sphenoid sinuses. We diagnosed him with cavernous sinus syndrome caused by mucormycosis and conducted endoscopic sinus surgery to remove remaining lesions and decompress orbit and optic nerves.

After the revision surgery the patient's headache and ophthalmoplegia were improved. However, multifocal cerebral infarctions were newly discovered in a postoperative CT scan. We experienced a case of mucormycosis of sphenoid sinus resulting in occlusion of internal carotid artery and multifocal cerebral infarction, and report it with a brief review of these disease entities.