Traditional Anthropometrics versus Computerized Photograph Manipulation in Rhinoplasty Planning

Overview

Rhinoplasty planning traditionally uses measurements and ideal ratios to determine what should change, such as nasal length and tip projection. Computer manipulation of photographs has more recently been used to show patients the planned result and improve communication. It was unknown whether the changes prescribed by measurement match those an experienced surgeon produces when editing photographs toward an aesthetic ideal.

Sections of note

• Analysis of preoperative photographs from 97 consecutive rhinoplasty or septorhinoplasty patients; level of evidence IV.
• Mean patient age 35.4 years; 68 percent female.
• Facial and nasal measurements were taken from the photographs, and the Byrd and Hobar analysis was used to calculate ideal values.
• Separately, the senior author manipulated the same photographs by computer toward an aesthetically pleasing nose, and those images were measured.
• Average proportions from the manipulation were nasal length at 76.1 percent of midfacial height, tip projection at 57.7 percent of nasal length, and radix projection at 24.3 percent of nasal length.
• Computer manipulation changed nasal length minimally, 100.3 percent of original, against Byrd's 88.2 percent, P less than 0.01.
• It prescribed a greater decrease in tip projection, 97.7 percent against 99.9 percent, P equals 0.05.
• It prescribed a lesser increase in radix projection, 100.5 percent against 109.3 percent, P less than 0.01.

What it means for a patient

• The two planning methods disagree, most sharply on nasal length, where measurement analysis calls for a 12 percent reduction and the surgeon's edit calls for none.
• Simulated images shown in consultation may therefore not reflect what classical measurement would prescribe.
• The manipulations came from one surgeon, so they represent that surgeon's aesthetic rather than a general one.
• Neither method was checked against actual surgical results or patient satisfaction.

Why this paper matters

Planning and simulation are both used routinely, and this study shows they can point in different directions. It quantifies the divergence on three key dimensions. Which method better predicts a satisfying result is not addressed.

Terms

• Anthropometrics: measurement of body dimensions, here of the face and nose.
• Byrd and Hobar analysis: a published system of ideal nasal proportions used for planning.
• Nasal length: the distance from the root of the nose to the tip.
• Radix projection: how far the root of the nose stands forward.
• Midfacial height: the vertical distance across the middle third of the face.