Olfactory Outcomes After Endoscopic Transsphenoidal Pituitary Surgery

Background: Olfaction has been demonstrated to have a great impact on patients' lives. Transsphenoidal endoscopic pituitary surgery is associated with potentially significant damage to olfactory tissues, but to date this issue has been only poorly documented in the literature. Study Design: Prospective cohort study comparing olfactory outcomes pre- and postpituitary surgery. Method: Patients were administered the University of Pennsylvania Smell Identification Test (UPSIT) preoperatively and again at 6 months postoperatively. The endoscopic transsphenoidal pituitary surgery was carried out using a full middle turbinate preservation protocol. A Hadad-Bassagasteguy (HB) vascularized septal flap was raised in each case. Secondary outcomes included Lund-Kennedy endoscopy scores (LKES) and patient self-report of olfactory disturbance. The results were analysed using a paired t-tests. Results: Seventeen patients met inclusion criteria for the study. Mean preoperative UPSIT value was 37.2 (normosmia), and mean postoperative UPSIT value was 30.8 (moderate hyposmia) (P < .001). All patients were fully healed with normal LKES scores by 6 months. All patients complained of their olfactory dysfunction. Conclusions: This study is the first to describe postoperative olfactory perturbations suffered by patients undergoing endoscopic transsphenoidal pituitary surgery. We hypothesize that olfactory impairment results from use of the HB flap. We recommend that the possibility of permanent olfactory changes be added to routine patient counseling and consent for this procedure, and that HB flaps be raised judiciously during trannssphenoidal endoscopic procedures.