Comparative Analysis of Anterior and Posterior Nasal Compartments in Patients with Symptoms of Nasal Obstruction

Introduction: Nearly half of patients report persistent nasal obstruction after surgeries targeting the anterior nasal valve (i.e., septum, inferior turbinate). Currently, the posterior nasal cavity is neither routinely assessed nor medically or surgically addressed. In this study, we tested novel computed tomography (CT) measures of posterior nasal narrowing on nasal symptoms.

Methods: This cross-sectional study evaluated a cohort of patients presenting to a PAP alternatives clinic from 2023 to 2025 who had documented Nasal Obstruction Symptom Evaluation (NOSE) scores and available CT imaging. CT measurements were performed at 4 coronal cross-sections from anterior to posterior. Specifically, at each coronal cross-section, bony wall-to-wall, turbinate neck-to-neck, and septal widths were measured. Pearson correlation coefficients were calculated to assess the relationship between anatomic characteristics and nasal obstruction.

Results: Patients (n=50) were, on average, middle-aged (48.2±13.3 years), male (70%), overweight (28.6±3.7 kg/m2), and had severe obstructive sleep apnea (AHI 34.4±19.8 events/hr) and moderate nasal obstruction (NOSE 37±25.7). Among patients without prior surgery on the anterior nasal compartment (n=36), decreased piriform width was moderately correlated with increased NOSE score (r=-0.45, p=0.007). Among patients who had previously undergone anterior nasal surgery (n=14), decreased width between the middle turbinates at the level of the descending palatine artery moderately trended with increased NOSE score (r =-0.44, p=0.12).

Conclusions: Our findings confirm that anterior nasal narrowing is significantly associated with symptoms of nasal obstruction. However, posterior nasal narrowing may also contribute to symptoms of nasal obstruction, particularly in patients who have undergone prior septoplasty or inferior turbinate reduction. These findings may help explain why roughly half of patients continue to experience symptoms despite prior anterior nasal surgery. Thus, our results highlight the need to further characterize posterior sources of nasal obstruction.