Nasal obstruction is a common condition that significantly impairs nasal breathing and reduces patients’ quality of life. It can result from various anatomical and physiological abnormalities, including septal deviation, turbinate hypertrophy, and mucosal inflammation [1]. Beyond breathing difficulties, nasal obstruction also affects sleep quality, physical activity, and overall well-being, often prompting patients to seek medical intervention [2].

The septal swell body (SSB), a distinct anatomical structure located in the anterior nasal septum, has been identified as an important contributor to nasal obstruction [3]. This dynamic tissue, which contains rich vasculature and glandular components, can undergo physiological changes in size that correspond to fluctuations in nasal airflow [4,5]. Septal swell body volume reduction (SSBVR) was developed as a targeted intervention to address this anatomical contributor to nasal obstruction. Various techniques, such as radiofrequency ablation and coblation, have shown promise in reducing SSB volume while preserving mucosal function [6,7]. Early studies have reported improvements in nasal breathing and patient satisfaction, along with the advantage of being less invasive than traditional surgical approaches [2,8].

Traditional surgical treatments for nasal obstruction, including septoplasty and turbinate reduction, aim to correct structural deviations or reduce hypertrophic tissue narrowing the airway [9,10]. While septoplasty reshapes a deviated septum to improve airflow, and turbinate reduction targets hypertrophic inferior turbinates to decrease nasal resistance, addressing the SSB may be critical for managing persistent obstruction after these procedures [11]. Although SSBVR appears promising, comprehensive data on its long-term efficacy, safety, and patient-reported outcomes remain limited, emphasizing the need for further research into its role in nasal airway function [3,12].

This meta-analysis investigated the clinical impact of SSBVR by assessing its effects on nasal obstruction, cross-sectional area, and nasal resistance. Outcomes in patients undergoing SSBVR were compared before and after treatment. Additionally, we explored the potential benefits of combining SSBVR with turbinate surgery versus performing turbinate surgery alone. Subgroup analyses evaluated variations in outcomes based on follow-up duration and treatment modalities, such as topical decongestants, coblation, and radiofrequency.

As shown in Fig. 1, data from 232 patients across seven studies were ultimately included. The characteristics of each study are summarized in Table 1. Overall patient characteristics could not be pooled because not all studies completely reported patient information. Study bias was summarized in Supplementary Tables 1 and 2.

The findings from this meta-analysis suggest that SSBVR is highly effective for improving nasal obstruction, cross-sectional area, and nasal airway resistance, while incurring minimal adverse effects. The incidence of complications—septal perforation, synechia, and epistaxis—was relatively low, between 1.3% and 1.72%. Significant improvements in nasal obstruction scores were evident at all follow-up points, increasing up to 12 months posttreatment. Furthermore, although data were only confirmed at 3 months, patients who underwent SSBVR in addition to turbinate surgery showed greater improvement in nasal obstruction than those who had turbinate surgery alone, indicating that SSBVR could offer benefits as a supplementary procedure.

The SSB is a convex, anterosuperior structure on the nasal septum, located above the inferior turbinate and anterior to the middle turbinate [14,15]. It consists of soft tissue protruding from the perpendicular plate of the ethmoid or septal cartilage and is covered by thickened mucosa. Originally identified in 1662, it has been referred to by several names, including the septal turbinate, septal cavernous body, and Kiesselbach’s ridge [4,16,17]. Although it can be clearly seen on computed tomography and magnetic resonance imaging, the SSB has received relatively little clinical attention [18].

The internal nasal valve, formed by the angle between the caudal edge of the upper lateral cartilage and the nasal septum, is the narrowest part of the nasal airway where airflow turbulence occurs during both inspiration and expiration [19]. Known to play a pivotal role in nasal obstruction, the nasal valve can be effectively managed with surgical procedures [20]. Morphometric evaluations from imaging and cadaveric studies show that the point of maximal protrusion in the SSB often aligns closely with the caudal end of the inferior turbinate, overlapping portions of the internal nasal valve [15,21]. Histologically, the SSB contains venous sinusoids similar to those found in the inferior turbinate [4]. Therefore, it shares similar physiological responses, such as sensitivity to antihistamines and decongestants [22,23]. Located near the internal nasal valve, the narrowest segment of the airway, the SSB can influence airflow dynamics, and growing evidence suggests its involvement in nasal obstruction pathophysiology.

Our results revealed statistically significant improvements in nasal obstruction symptoms among patients undergoing SSBVR compared to those who did not. Over time, the SSBVR group displayed a large effect size for improved nasal obstruction, indicating that mucosal contraction may accumulate and offer prolonged benefits. In contrast, substantial heterogeneity was detected during the early postoperative period, likely due to differences in patient populations, surgical methods, and baseline nasal obstruction severity. These complexities highlight the challenges of assessing early postoperative outcomes in diverse patient groups. At 12 months, however, the long-term effects showed the largest effect size with no heterogeneity. Despite employing different surgical techniques (coblation and radiofrequency) in the long-term analysis, the results were highly consistent. Both coblation and radiofrequency produce remodeling effects through submucosal fibrosis, coagulative changes, and a reduction in venous sinusoids, as observed in inferior turbinate surgery [24,25]. Subgroup analyses confirmed notably larger effect sizes for both coblation (SMD, 2.66; 95% CI, 1.71 to 3.60) and radiofrequency (SMD, 3.03; 95% CI, 2.87 to 3.18) compared to the immediate symptom relief from topical decongestants (SMD, 0.47; 95% CI, 0.27 to 0.67). Although early postoperative heterogeneity limits direct comparisons, these findings strongly support the long-term efficacy of coblation and radiofrequency for treating SSB, reinforcing their roles in achieving sustained nasal obstruction improvement.

In our analysis, despite the relatively small patient sample, performing SSBVR alongside turbinoplasty led to a significant improvement in subjective nasal obstruction scores compared to turbinoplasty alone, although objective measures like cross-sectional area and nasal airway resistance did not show corresponding improvements. Notably, the effect size for SSBVR plus turbinoplasty (SMD, 0.47; 95% CI, 0.24 to 0.70) was smaller than that for SSBVR alone (SMD, 2.54; 95% CI, 1.81 to 3.26). It is presumed that the dominant effects of turbinoplasty may overshadow the incremental benefits of SSBVR. Interpreting these findings requires caution due to several factors. First, no study to date has examined the long-term outcomes of adding SSBVR to turbinoplasty beyond 6 months, including cross-sectional area or nasal airway resistance. Second, the discrepancy between marked improvements in subjective nasal obstruction and minimal changes in objective measures may reflect underlying structural and physiological complexities that are not fully represented by cross-sectional area or nasal airway resistance. Additional research is necessary to elucidate these differences, especially through well-designed studies that incorporate both subjective and objective assessments over extended periods.

This study provides valuable insights into the effectiveness of SSBVR for enhancing nasal obstruction, yet certain limitations must be acknowledged. Significant heterogeneity was apparent in some analyses, particularly for nasal obstruction scores at early follow-up. This variability is likely due to differences in patient populations, procedural techniques, and outcome measurement methods across the included studies. Additionally, the absence of I² values in certain analyses restricted full evaluation of variability and consistency. The limited long-term data and generally low quality of included studies further impede definitive conclusions about the cumulative and durable advantages of SSBVR. It is also essential to account for potential alternative explanations for observed improvements, such as reversion to the mean over extended follow-up or placebo effects, which can be especially influential in surgical contexts. Future well-designed, prospective, multicenter trials with longer follow-up periods, standardized methodologies, and thorough evaluations of both subjective and objective measures are critical for formulating reliable clinical recommendations on the long-term safety and efficacy of SSBVR.