Superior turbinate management and olfactory outcome after endoscopic endonasal transsphenoidal surgery for pituitary adenoma: a propensity score‒matched cohort study

Abstract

Background: Surgical management of the superior turbinate (ST) is required to access the sella in endoscopic endonasal transsphenoidal surgery (EETS) for pituitary adenoma. Two common ST management techniques include partial resection of the ST (PRST) and intentional lateralization of the ST (ILST). Given the concentrated distribution of the olfactory nerve fibers on the medial surface of the ST, in this study we aimed to ascertain whether PRST worsens the objective olfactory outcome when compared with ILST. Methods: A retrospective, propensity score‒matched cohort study was performed at a tertiary referral center. A total of 232 adult patients undergoing EETS for pituitary adenoma were analyzed. The threshold test (STT) and the 12-item identification test (SIT-12) from “Sniffin’ Sticks” were administered for separate nostrils preoperatively and 6 months postoperatively. Results: Of 232 patients, 109 had right-sided PRST and 123 received right-sided ILST. Propensity score matching—controlling for olfactory-related confounding factors, including gender, age, medical comorbidities, surgical technique, and preoperative olfaction—resulted in 74 matched pairs. When comparing the 6-month postoperative olfactory performance of the right nostril, the STT score was significantly lower in the PRST group than the ILST group (p = 0.036, η2 for effect size estimate = 0.030), but the SIT-12 scores were similar in the 2 groups (p = 0.325). Overall, the olfactory outcomes for the right nostril did not qualitatively differ between the PRST and ILST groups (p = 0.401). Conclusion: Despite its association with threshold impairment, PRST in EETS does not seem to carry an additional risk of postoperative olfactory dysfunction.