Does Septoplasty Interfere with Sense of Smell?
Septoplasty does not interfere with the sense of smell; rather, it typically improves olfactory function in patients with nasal obstruction due to septal deviation. 1, 2
Evidence for Olfactory Improvement
Multiple high-quality studies demonstrate that septoplasty leads to measurable improvements in smell:
A 2021 systematic review and meta-analysis of 996 patients found significant improvement in all olfactory test scores following septoplasty, with pre- and postoperative differences showing improvements of 0.63 for BSIT, 0.80 for CCCRC test, 1.16 for odor threshold, 1.43 for odor discrimination, and 1.18 for odor identification. 1
A 2023 prospective study of 47 patients demonstrated that septoplasty and/or turbinoplasty produce significant improvements in both lateralized and bilateral olfactory function, with patients showing worse smell function on the more obstructed side preoperatively, which improved significantly 12 months after surgery. 2
A 2019 prospective study of 60 patients confirmed that smell was significantly compromised due to septal deviation, especially in the more obstructed nasal cavity side, and improved significantly after septoplasty along with increased nasal patency. 3
Mechanism of Improvement
The improvement in olfaction following septoplasty occurs through several mechanisms:
Increased nasal airflow allows better delivery of odorant molecules to the olfactory epithelium, with studies showing significant correlation between increased nasal cavity volume and improved olfactory thresholds. 3
Improved nasal patency enhances the perception of nasal airflow, which contributes to better smell perception beyond just anatomical changes. 4
Septoplasty improves the internal nasal valve area, which is responsible for more than two-thirds of nasal airflow resistance and directly impacts olfactory function. 4, 5
Subjective vs. Objective Outcomes
There is an important distinction between subjective and objective olfactory measurements:
Subjective olfactory scores consistently improve after septoplasty, with patients reporting better smell perception on visual analog scales and olfaction-specific quality of life questionnaires. 6, 3
Objective testing (such as UPSIT) may not always show statistically significant changes, though other validated tests like Sniffin' Sticks demonstrate measurable improvements. 6, 4
The degree of improvement in subjective smell correlates moderately with the extent of improvement in nasal obstruction symptoms (r = 0.51-0.55), suggesting that patients who experience greater relief from obstruction also report better olfactory function. 6
Clinical Implications
Patients should be counseled preoperatively that septoplasty is likely to improve rather than harm their sense of smell, particularly if they have pre-existing olfactory impairment related to nasal obstruction. 3
Normosmic patients who maintain or improve their smell after surgery report higher personal benefit from septoplasty than patients with remaining olfactory deficits. 3
The improvement in smell is not equal for all patients, with the outcome being discrete and variable, though the overall trend is toward improvement rather than deterioration. 1
Assessment of olfactory function prior to nasal surgery is important from a medico-legal perspective, as patients may have concerns about potential changes to their sense of smell. 7