Background Unilateral cleft lip nasal deformity (uCLND) creates multiple sites of potential nasal functional airway obstruction, which impact patients’ overall quality of life. Surgical restoration of function remains technically challenging and complex. Learning objectives To determine if variability in patient outcome is due to incomplete or inadequate surgical intervention, or an incomplete understanding of the anatomic structural causes of obstruction. Study objective This ongoing research is funded by the National Institutes of Health to investigate effectiveness of current septorhinoplasty techniques in improving patient outcomes. Design Type Prospective study involving computational fluid dynamics (CFD) modeling of the uCLND nasal airway to evaluate nasal patency before and after septorhinoplasty. Method Pre- and post-surgery radiographic images of patients with uCLND were obtained for creation of patient-specific nasal models. Airflow simulations were performed in each nasal model using CFD. Localized resistance values at multiple cross-sectional segments were determined and used to identify anatomic sites of greatest nasal obstruction. Results Preliminary analysis on Subject 1 shows these changes after surgery: bilateral nasal resistance decreased from 0.155Pa.s/ml to 0.061Pa.s/ml, cleft-sided resistance decreased from 0.407Pa.s/ml to 0.091Pa.s/ml, and non-cleft-sided resistance decreased from 0.228Pa.s/ml to 0.120Pa.s.ml. On the cleft side, 24 identified sites of obstruction decreased to 15 sites post-surgery; on the non-cleft side, 23 sites of obstruction decreased to 16 sites post-surgery. Post-surgical resistance values were within normative levels. Conclusion Preliminary results suggest improvement in nasal patency after septorhinoplasty to healthy ranges in this subject. However, there exist additional sites of greatest obstruction in the post-surgical airway.