Clinical Predictors of Frontal Ostium Restenosis After Draf 3 Procedure for Refractory Chronic Rhinosinusitis.

Background The Draf 3 procedure has been demonstrated to be effective in the treatment of refractory frontal sinus disease. A variety of clinical factors may contribute to the change of frontal neo-ostium (FNO) area after this procedure. Imaging plays a vital role in the evaluation and follow-up after surgery and provides useful prognostic information. Objectives (1) To investigate the influence of local anatomic factors on FNO after a Draf 3 procedure by radiological measurements on imaging software and (2) to explore other predictive factors of FNO restenosis. Methods Twenty-four patients with chronic rhinosinusitis who underwent a Draf 3 procedure and were followed up for more than 12 months (2012-2014) were enrolled in this study. Data on patient demographics, medical history, and computed tomography scans were collected. Anatomic dimensions were measured with OsiriX® (Pixmeo, Geneva, Switzerland). Stenotic ostium was defined as a loss of more than 50% of the original intraoperative area. Multivariate linear regression was used to assess independent factors linked to frontal neo-osteogenesis 1 year after the surgery. A receiver operating characteristic curve was built for the cutoff value of preoperative dimension to predict restenosis of FNO area. Results A significant association was demonstrated between the minimum anteroposterior diameter (FOAP) of the frontal ostium preoperatively and FNO area 1 year postoperatively. Multivariate linear regression showed that FOAP of the frontal ostium preoperatively and the percentage of serum eosinophils (EOSs) correlated with the contour area of the FNO 1 year postoperatively. FOAP ≤ 3.592 mm yielded a sensitivity of 95% and a specificity of 75% for the diagnosis of FNO restenosis. Conclusions Both FOAP and EOS are independent predictors of the contour area of the FNO 1 year postoperatively. Patients with a higher risk of developing frontal ostium restenosis can be identified preoperatively by measurements of the frontal sinus anatomic dimensions.