Quality of life and olfactory outcomes following frontal sinus drill-out procedures

Objective: Extensive endoscopic frontal sinus surgery requires drilling of the bone close to the olfactory epithe-lium and exposing the first olfactory fiber. This study assesses long-term quality of life (QoL) and olfactory outcomes following endoscopic endonasal frontal sinus drill-out procedures.Methods: All patients who underwent endoscopic endonasal frontal sinus surgery (Draf IIa or Draf III) for chronic rhinosinusitis (CRS) without nasal polyp in 2017 at a single tertiary center were included in the study. Pre-and postoperative scores of SNOT-22, odor identification, discrimination, and threshold were noted.Results: Of the 31 patients included in this study, Draf IIa and Draf III were performed in 12 (38.7 %) and 19 (61.3 %) patients, respectively. A general assessment of QoL changes was carried out by evaluating pre-and postoperative SNOT-22 scores. A statistically significant difference was found between pre-and postoperative SNOT scores (p < 0.001): SNOT scores decreased by 9.13 units postoperatively. Comparing differences in SNOT -22 and olfactory test scores between Draf IIa and Draf III patients, we did not detect any statistically significant difference between the two procedures (p > 0.05). Draf IIa and Draf III did not display a statistically significant difference in SNOT-22 scores (p = 0.484) and did not have a significant effect on differences in pre-and post-operative identification (p = 0.675), discrimination (p = 0.535), and threshold (p = 0.141) scores. Conclusions: Our study demonstrated that extensive drill-out procedures have not a negative effect on olfactory functions, including threshold scores, in the long term. Patients who underwent frontal sinus procedures for persistent CRS have a better QoL postoperatively. However, more prospective double-blind studies are needed to support our results.