Sphenopalatine arteriovenous fistula complicating transsphenoidal pituitary surgery: A rare cause of delayed epistaxis treatable by endovascular embolization

BACKGROUND Vascular injuries in transsphenoidal surgery for pituitary adenomas are uncommon but can result in serious disability or death. CASE DESCRIPTION A 46-year-old man, who underwent resection of a pituitary adenoma with suprasellar extension via a transsphenoidal approach, presented with massive epistaxis five days postoperatively. Angiography revealed an arteriovenous fistula (AVF) between the right sphenopalatine artery and a deep vein draining to the right internal jugular vein, as well as contrast agent extravasation at the fistula point. The AVF was catheterized and successfully occluded with N-butyl-2-cyanoacrylate. CONCLUSIONS Transsphenoidal pituitary surgery can be complicated by massive epistaxis from a lesion of a small branch of the external carotid artery. Airway protection through intubation and investigation with conventional digital subtraction angiography is recommended. The treatment of choice is endovascular embolization because it can be done immediately at the angiography suite.