Nasal polyp

Nasal polyps are polypoidal masses arising mainly from the mucous membranes of the nose and paranasal sinuses. Nasal polyps are usually classified into antrochaonal polyps and ethmoidal polyps. Antrochaonal polyps arise from the maxillary sinuses and the ethmoidal polyps arise from the ethmoidal sinuses. Antrochoanal polyps are usually single and unilateral whereas ethmoidal polyps are multiple and bilateral. Symptoms of polyps include nasal block, anosmia or loss of smell, and secondary infection leading to headache.