Nasal Polyps By Marvin P Fried, MD, Montefiore Medical Center, The University Hospital of Albert Einstein College of Medicine Reviewed / Revised Dec 2021 | Modified Sep 2022 View Patient Education Treatment Topic Resources Nasal Polyp Nasal polyps are fleshy outgrowths of the nasal mucosa that form at the site of dependent edema in the lamina propria of the mucous membrane, usually around the ostia of the maxillary sinuses.