Site of origin of nasal polyps: relevance to pathogenesis and management.

The site of origin of sino-nasal polyps was documented in 113 consecutive patients undergoing functional endoscopic sinus surgery (FESS). These patients were assigned pre-operatively to 4 clinical groups according to the out-patient recorded endoscopic appearance of their nasal cavities; chronic rhinosinusitis without polyps (CRSS) n=35, grade 1 polyps n=28, grade 2 polyps n=30 and grade 3 polyps n=20. In the group of patients diagnosed with polyps pre-operatively, 97.4% had polyps originating in the anterior ethmoid complex, of which 89.7% had polyps originating in the anterior ethmoidal cells and over 60% had polyps specifically originating from each of the following sites: the uncinate or infundibulum, the posterior ethmoid sinus, the frontal recess and the face of the bulla ethmoidalis. In the group diagnosed pre-operatively as CRSS without polyps, polyps were found in 60% of patients within the sinuses during surgery. In summary, our findings suggest that polyps originate from the middle meatus, and may be found at surgery when undetectable at pre-operative endoscopy.