Assessment of rhinoplasty techniques by overlay of before-and-after 3D images

Overview

Standard photographs show a nose from fixed angles and cannot measure volume. Three-dimensional imaging captures the whole surface. The authors describe the camera equipment and software used, discuss whether its measurements are valid and repeatable, and set out methods for reading the surgical change when the preoperative and postoperative scans are superimposed.

Sections of note

• Technical and descriptive article; the abstract gives no patient series or outcome figures.
• Covers the hardware and software used to create facial 3D images.
• Discusses validation and reliability of objective measurements made with the equipment.
• Preoperative and postoperative scans are overlaid to show change in three dimensions.
• Methods are given for four technique groups: dorsal augmentation, increasing tip projection, narrowing the nose and nasal lengthening.

What it means for a patient

• Some practices can scan the face in 3D and later show exactly where the nose changed and by how much.
• The same tool can be used to plan and to check whether the planned change was achieved.
• The abstract does not report how accurate the measurements are in numbers or how many patients were assessed.

Why this paper matters

Objective measurement of rhinoplasty results has lagged behind technique. This article, from a group known for structural rhinoplasty, describes a way to quantify outcomes technique by technique. Whether 3D measurements track patient satisfaction is not addressed.

Terms

• 3D imaging: capturing the surface of the face as a digital model that can be rotated and measured.
• Overlay: placing the before and after models on top of each other to see the difference.
• Dorsal augmentation: raising the height of the nasal bridge.
• Tip projection: how far the tip stands out from the face.
• Nasal lengthening: surgery to make a short nose longer, usually by extending the septum.
• Validation: testing whether a measurement method gives accurate and repeatable results.