Synmastia after breast augmentation.

[BACKGROUND] Synmastia after breast augmentation is a condition of aberrant communication of the breasts caused by violation of the chest midline by medial migration of one or both implants. This condition, though rare, has been seen with increasing frequency in the authors' practice.

[METHODS] The records of 20 women with synmastia were reviewed. Data collection for these women included their preoperative repair history, implant sizes, and breast to chest wall proportions.

[RESULTS] All of the previous augmentations were subpectoral. Ten of the patients had undergone multiple augmentation operations. Twelve patients had implants that appeared excessively wide for their chest.

[CONCLUSIONS] Synmastia is a difficult surgical complication to address. Patients with multiple breast operations, excessively large implants, and overaggressive medial dissection are susceptible to developing synmastia. Understanding these potential risk factors leading to synmastia should help prevent its occurrence.