Peak nasal inspiratory flow is a useful measure of nasal airflow in functional septorhinoplasty.

<bold>Objective: </bold>To evaluate the utility of peak nasal inspiratory flow (PNIF) as a measure of nasal airflow and functional septorhinoplasty (FSRP) outcomes.<bold>Methods: </bold>Patients with nasal obstruction were administered Nasal Obstruction Symptom Evaluation (NOSE) questionnaire and PNIF testing between January 2015 and 2018. Surgical patients repeated these tests at 2, 4, 6, 12, and 24 months postoperatively. Patient demographics and operative techniques were recorded.<bold>Results: </bold>A total of 610 patients were evaluated for nasal obstruction with mean (standard deviation [SD]) NOSE score of 61.5 (23.2) and PNIF of 74.1 (35.4) liters per minute (L/min); correlation -0.16 (P < 0.001). Predictors of lower PNIF were female gender (β = -13.3, 95% confidence interval [CI] 7.7 to 18.2, P < .001) and higher NOSE scores (β = -0.43, 95% CI 0.19 to 0.68, P < 0.001). A total of 281 patients underwent FSRP with statistically and clinically significant improvements in both mean NOSE and PNIF scores that were stable out to 2 years. NOSE scores changed -41.0 (25.5) points, and PNIF improved 20.7 (35.5) L/min at last follow-up. Grafting material did not affect outcomes, whereas spreader grafts improved PNIF values (β = 25.46, 95% CI 5.5 to 45.4, P = 0.013). Clinically significant changes between NOSE and PNIF were concordant, although the correlation was weak (r = -0.26, P = 0.02).<bold>Conclusion: </bold>Peak nasal inspiratory flow is a rapid, cheap, and easily performed test that detects nasal obstruction and clinically significant improvements in airflow following FSRP. Although PNIF does not correlate well enough with the patient experience of nasal obstruction to be used as a diagnostic tool, it does provide unique and complementary information useful for evaluating, understanding, and improving the effects of surgical techniques.<bold>Level Of Evidence: </bold>2C Laryngoscope, 129:594-601, 2019. [ABSTRACT FROM AUTHOR]