Impact of Dorsal Preservation Rhinoplasty Versus Dorsal Hump Resection on the Internal Nasal Valve: a Quantitative Radiological Study

Abdelwahab MA, Neves CA, Patel PN, Most SP.

PubMed 32016500 Publisher (DOI)Free full text (PMC)

What this paper says

In a cadaver study of six heads, the push-down preservation technique significantly narrowed the internal nasal valve, while conventional hump removal with midvault reconstruction and the let-down technique did not.

Overview

Dorsal preservation lowers the bridge by dropping the whole roof rather than removing it, and the two variants differ in whether bone is removed from the side wall. This study measured what each does to the narrowest part of the airway, using imaging on cadaver specimens before and after each procedure.

Sections of note

Cadaveric study of six heads, randomly divided between conventional hump resection with midvault reconstruction and dorsal preservation techniques.
Group A: conventional hump resection, 6 sides. Group B: push-down, 6 sides. Group C: let-down performed subsequently on the same heads, 6 sides.
A validated radiological method measured the internal nasal valve angle and cross-sectional area in a modified coronal plane before and after each procedure.
Group A showed no significant reduction in valve angle or cross-sectional area, p 0.068 and p 0.156.
Group B, push-down, showed a mean change of 2.05 degrees in angle and 0.3 square centimeters in cross-sectional area, p 0.0163 and p below 0.001.
Group C, let-down, showed no significant reduction in angle or area, p 0.437 and p 0.331.
Level of evidence III.

What it means for a patient

The two preservation variants are not equivalent for breathing: push-down narrowed the airway, let-down did not.
Push-down pushes the whole nasal roof down into the surrounding bone, which the measurements suggest compresses the valve.
Conventional hump removal, when the middle vault is rebuilt, did not narrow the valve.
Limits: six cadaver heads, so this measures anatomy rather than breathing, and no living patients or symptom outcomes are involved.

Why this paper matters

Dorsal preservation is often presented as a single technique, and this shows one of its two variants carries an airway cost the other does not. That is directly relevant to technique selection. Cadaver measurements do not establish that patients experience obstruction.

Terms

Dorsal preservation rhinoplasty: Lowering the bridge by dropping the whole nasal roof rather than shaving it off.
Push-down: Dropping the nasal roof straight down into the face.
Let-down: Removing a wedge of bone so the roof settles lower.
Internal nasal valve: The narrowest part of the nasal airway.
Cross-sectional area: The measured area of the airway at a given point.

Summary written by rhinoplasty.cc from the abstract, 2026-09-09; not medical advice. The authors' own abstract follows.

Abstract

Background: This study evaluates the impact of different hump takedown techniques, namely the conventional hump resection with midvault reconstruction, the push-down (PD) and the let-down (LD) procedures, on the INV dimensions.

Methods: In this cadaveric study, six heads were divided randomly into either the conventional hump resection technique (Group A; n = 6 sides) or DPR techniques (n = 6 sides). This latter group was subdivided such that initially a PD procedure was performed (Group B; n = 6 sides), followed by a LD procedure on the same heads (Group C; n = 6 sides). A validated radiological method was used to measure the INV angle and cross-sectional area (CSA) in a modified coronal plane both pre- and post-procedurally.

Results: Group A did not show significant reduction in the INV angle nor in CSA (p = 0.068 and p = 0.156, respectively). In the push-down group (B), we observed a mean change of 2.05° in the angles and 0.3 cm2 in the CSA (p = 0.0163 and p < 0.001, respectively). The LD group (C) did not show significant reduction in the INV angle nor in CSA (p = 0.437 and p = 0.331, respectively).

Conclusion: Neither the conventional hump resection nor the LD DPR technique reduced the INV dimensions. However, the PD preservation technique significantly reduced the INV dimensions.

Level Of Evidence Iii: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Abstract as indexed by PubMed; the article is open access (PubMed Central).