This study aimed to investigate the impact of residual ethmoidal laminae after endoscopic sinus surgery (ESS) in patients with chronic rhinosinusitis with nasal polyps (CRSwNP).

This retrospective cohort included 66 patients with CRSwNP who received 300mg of dupilumab every 2weeks for 16weeks between August 2020 and March 2022. Patients were categorized into the no-lamina or residual-lamina groups based on postoperative sinus computed tomography scans. Clinical parameters, including the Lund-Mackay score (primary endpoint), nasal polyp score, T&T olfactometer threshold, and SNOT-22 scores (secondary endpoints), were assessed at baseline and 16weeks posttreatment.

Of 66 patients who received dupilumab, 51 met the inclusion criteria. The no-lamina (n=23) and residual-lamina (n=28) groups exhibited similar baseline characteristics. At 16weeks, the Lund-Mackay Score significant improved in the no-lamina group compared with the residual-lamina group (5±4 vs. 9±4; P=0.004). Non-significant differences were observed in nasal polyp score (2.6±1.6 vs. 3.3±2.0; P=0.22), T&T olfactometer threshold test score, (3.2±1.8 vs. 3.3±1.4; P=0.78) SNOT-22 score, (18±11 vs. 24±13; P=0.15).

This study suggests an association between the absence of residual ethmoidal laminae and an enhanced dupilumab response in CRSwNP. Residual laminae in the anterior ethmoid affect the effectiveness of dupilumab in targeting inflammatory pathways. Meticulous clearance, particularly in the anterior ethmoidal region, optimizes the efficacy of dupilumab. Understanding the influence of residual ethmoidal laminae on dupilumab outcomes is crucial for refining post-ESS treatment strategies for patients with CRSwNP.