Breast and chest asymmetries: classification and relative distribution of common asymmetries in patients requesting augmentation mammoplasty

Asymmetries of the breast and chest wall are common but a comprehensive classification of these asymmetries and their relative distribution is lacking in the literature. These asymmetries can be primarily due to breast size and shape or nipple areolar complex size or level discrepancy respectively. Breast asymmetries may also arise secondarily due to abnormalities of the underlying bony or soft tissues. A prospective recording of 312 augmentation mammoplasties performed by the author, from January to December 2007, were reviewed to assess breast and chest wall deformities together with an incidence and their relative distribution. From January to December 2007, 312 augmentation mammoplasties were performed. Mean age of the patients was 30.4 ± 9.1 years (range 18–58). Mean size of the implant was 325 ± 53 cm³ (range 200–620). Different size implants were used in 9% patients with a mean difference of 56.3 ± 33.7 cm³ (range 20–180). Patients were assessed for asymmetry of breast, chest, distance between jugular notch to nipple areolar complex and nipple areolar complex to inframammary crease. Breast Volume Asymmetries: Breasts were symmetrical in 53.5% (n = 167). Left breast was larger in 29.8% (n = 93) as compared to 16.7% (n = 52) on the right, and the difference was significant (P value < 0.001). Chest Wall Asymmetries: Chest wall was symmetrical in 89.7% (n = 280) and thoracic deformities or asymmetries were seen in 8.6% (n = 27). Chest wall and ribs were more prominent on the left side in 6.7% (n = 21) as compared to 1.9% (n = 6) on the right, and the difference was significant (P value < 0.003) Pectus excavatum and carinatum was seen in 0.6% (n = 2) and 1% (n = 3), respectively. Jugular Notch to Nipple Areolar Complex Distance Differences: Jugular notch to nipple areolar complex (NAC) distance was same on two sides in 67.2% with a mean distance of 19.7 cm (n = 207). In group (21.4%) with the left breast NAC lower (n = 66) the mean left NAC was 20.7 cm when compared to 19.04 cm on right. In group (11.2%) with right NAC lower than the left (n = 35), the mean NAC on the right was 21.2 cm as compared to 20.4 cm on the left. The left breast NAC (n = 66) was measured almost twice as low as the right (n = 35), and the difference between the two groups was significant (p value < 0.001). Nipple Areolar Complex to Inframammary Crease Distance Differences: Nipple to inframammary crease (IMC) distance was similar in 77.1% of patients with a mean of 6.69 cm. The group (n = 40) with higher measured distance on the left (13.1%), left mean nipple to IMC crease distance was 6.9 cm as compared to 6.17 cm on the right. The group (n = 30) with a higher measured nipple to IMC distance on the right (9.8%), the mean distance on the right was 7.12 cm as compared to 6.52 cm on the left. Though the incidence of the measured nipple to IMC distance was more common on the left (n = 40) than to the right (30), the difference between the two groups was without any statistical difference (p value = 0.2). A tuberous breast were seen in 3.9% (n = 12). Breast and chest wall asymmetries are common and majority of hyperplasias is seen on the left side. The majority of these patients may not require additional surgical manipulation or intervention however proper documentation is essential.