OBJECTIVE-To evaluate differences in endoscopy exam, olfactory function, and quality-of-life (QOL) status after endoscopic sinus surgery (ESS) for patients with and without bilateral middle turbinate (BMT) resection.STUDY DESIGN-Open, prospective, multi-institutional cohort SUBJECTS and METHODS-Subjects completing enrollment interviews, computed tomography, and endoscopy exam were asked to provide pre-and postoperative responses to the Smell Identification Test (SIT), Rhinosinusitis Disability Index (RSDI), Chronic Sinusitis Survey (CSS), and the Medical Outcomes Study Short Form-36 Health Survey (SF-36). Bivariate and multivariate analyses were performed at the 0.05 alpha level.RESULTS-47 subjects with BMT resection were compared to 195 subjects without BMT resection with a mean follow-up of 17.4 months postoperatively. Patients with BMT resection were more likely to have asthma (p=0.001), aspirin intolerance (p=0.022), nasal polyposis (p=0.025), and prior sinus surgery (p=0.002). Patients with BMT resection had significantly higher baseline disease burden measured by endoscopy, CT, and SIT scores (p<0.001). No significant differences in improvement were found in RSDI, CSS, or SF-36 scores between patients with BMT resection and those with BMT preservation (p>0.050). Patients undergoing BMT resection were more likely to show improvements in mean endoscopy (−4.5±5.2 vs. −1.9±4.3; p=0.005) and olfaction (5.3±10.8 vs 1.3±7.6, p=0.045) compared to those with BMT preservation.CONCLUSION-This investigation found no difference in baseline QOL between or QOL improvement after ESS. Patients undergoing BMT resection did, however, show greater improvements in endoscopy and SIT scores which persisted after controlling for confounding factors.