Question: A 28 year old woman with cystic fibrosis undergoes revision endoscopic sinus surgery for chronic rhinosinusitis.  Mega-antrostomies are created due to persistent maxillary sinus disease.  On postoperative day 2 she experiences brisk left sided epistaxis emanating from the posterior edge of the maxillary antrostomy near the floor of the nose.  What artery is the most likely culprit?

[Answer will be posted with next week's new question]

Answer to last week's question, "What Looms Beneath" (July 16, 2018)

Sturge-Weber syndrome.