Impact of Dorsal Preservation Rhinoplasty on the Internal Nasal Valve.

[BACKGROUND] The internal nasal valve (INV) is the airway's narrowest segment and main regulator of nasal resistance. Dorsal preservation rhinoplasty (DPR)-push-down (PD), let-down (LD), and spare roof (SR)-preserves dorsal structures, but its effect on INV angle is unclear. This study systematically evaluated INV angle changes after DPR.

[METHODS] We searched PubMed and Google Scholar (through April 2025) for studies reporting pre- and postoperative INV angles in DPR. Data were synthesized in RevMan 5.4 following PRISMA guidelines. The primary outcome was a change in the INV angle.

[RESULTS] Nine studies met inclusion criteria; 4 clinical studies (N = 118) were pooled. Meta-analysis showed a significant postoperative INV angle increase (standardized mean difference [SMD] = 0.52; 95% confidence interval [CI]: 0.02-1.02; = 0.04;  = 63%). Removing 1 outlier reduced heterogeneity to 0% and preserved significance (SMD = 0.43; 95% CI: 0.16-0.69; = 0.002). Cadaveric analysis (N = 46) demonstrated the greatest INV widening with SR (SMD = 1.42; = 0.02); PD showed a nonsignificant decrease (SMD = -1.65; = 0.15), and LD showed a positive, nonsignificant trend (SMD = 0.86). Technique-based subgroup differences were significant ( = 0.02).

[CONCLUSIONS] SR and LD techniques provide modest but meaningful INV angle improvement, supporting DPR as a functional alternative to traditional dorsal hump reduction. PD appears less reliable for valve patency. Larger, long-term studies with standardized functional measures are needed to refine technique selection.