BACKGROUND: Breast symmetry plays a key role in breast reconstructive surgery. In the healthy population, volume asymmetry is common. This study aimed to better understand how breast symmetry is perceived and to compare subjective estimation with objective measurements of breast symmetry in the healthy participants. METHODS: A retrospective cross-sectional study included healthy participants who underwent VECTRA 3-dimentional breast imaging. Breast volume measurements were obtained using the VECTRA system. Five plastic surgeons and five laypersons assessed volume symmetry subjectively. RESULTS: Of 209 healthy participants, 100 were randomly selected for assessment. Mean left and right breast volumes were 636.8 cc and 664.8 cc, respectively, with a mean relative volume difference of 16.0% (SD 12.7). No clear threshold of relative breast volume difference was found in which the majority of plastic surgeons or laypersons defined breast asymmetry. Even with large volume differences quantified by 3D VECTRA measurement, breasts were perceived as symmetrical by both plastic surgeons and laypersons. Inter-observer agreement was poor for both groups (Fleiss' kappa: surgeons 0.23; laypersons 0.30). Agreement with 3D measurements regarding the larger breast was low (surgeons: accuracy 53.8%, Cohen's kappa 0.08; laypersons: accuracy 48.6%, Cohen's kappa -0.07). CONCLUSIONS: Subjective assessments of breast symmetry by both experts and laypersons poorly correlate with objective 3D imaging volume measurements. Symmetry perception likely extends beyond volume alone, influenced by factors such as breast shape, projection, and nipple position. While 3D imaging provides reliable volume measurements and preoperative consultations, it alone may not enhance patient satisfaction regarding perceived symmetry. LEVEL OF EVIDENCE IV: 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 .
Killaars et al. (Wed,) studied this question.