Radiological findings in mammary autologous fat injections: a multi-technique evaluation

To describe the radiological appearance of normal and pathological findings resulting from mammary autologous fat injections (lipofilling).

Informed consent and institutional review board approval were obtained. From January 2008 to December 2010, all patients that had undergone breast lipofilling at our institution (Catholic University) were consecutively enrolled. The site and amount of autologous fat injections were known. Mammography, ultrasonography, and magnetic resonance imaging (MRI) were prospectively obtained preoperatively, and 6 and 12 months after the procedure. Normal and pathological findings were described.

Twenty-four patients (mean age 50.8 ± 10.5 years; range 26-70 years) were included. Fourteen patients underwent lipofilling after mastectomy, eight after wide local excision, one as a treatment for a congenital asymmetry, and one as a treatment for Poland syndrome. No severe complications were observed after treatment. Normal findings due to lipofilling ("oil cysts") were identified in 23 cases using ultrasound and in 16 using MRI. Liponecrosis, the most frequently observed complication, was detected in four cases using ultrasound and in eight by MRI. In one case mammography showed calcific fat necrosis. Mean amount of fat injected was 114.8 ± 55 ml. The average amount of fat grafted in patients who developed liponecrosis was 158.4 ± 42.7 versus 104.6 ± 52.3 ml (p = 0.0043, t-test). In one case breast cancer recurrence was diagnosed.

Normal findings due to lipofilling are better identified by ultrasound, and pathological findings are best identified using MRI. Liponecrosis most frequently occurs when large amounts of fat are injected. In the authors' experience lipofilling does not interfere with breast cancer early diagnosis.