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What is The main vessel involved in bleeding from Juvenile nasopharyngeal angiofibroma: and explain in detail?
Ans: C. Internal maxillary aery(Ref Dhingra 7/e p281-282, 5/261-263)Juvenile Nasopharyngeal Angiofibroma:MC benign tumor of nasopharynx (but overall angiofibroma rare).MC site:Posterior pa of nasal cavity close to the margin of sphenopalatine foramen.Seen exclusively in males of 10-20 years.Testosterone dependent tumor - Seen in pre-pubeal to adolescent males.Features:Locally invasive vasoformative tumor consisting of endothelium lined vessels with no muscle coat.Main feeding vessel in most cases = Internal maxillary aery.Internal maxillary aery - External carotid aery branch.