Prepectoral Breast Reconstruction Prompts Revisiting the Anatomic Boundaries of the Breast: A Radiographic and Cadaveric study

Background: This study aimed to determine the location of superficial fascial system (SFS) condensations in relation to classic anatomic breast boundaries. Cadaveric studies have provided some understanding, but knowledge about the precise location of these condensations remains limited. Methods: Preoperative breast MRI was conducted to assess the fascial condensations defining the breast footprint relative to landmarks like the latissimus, clavicle, sternal border, and inframammary fold (IMF). Concurrently, cadaveric mastectomies were performed to measure the breast borders in relation to these landmarks for comparison. Results: 290 breasts underwent preoperative MRI. Eight cadaveric breast dissections were completed. Radiographically, the lateral breast fascial condensation was 3.9 cm medial to the latissimus dorsi, while cadaveric measurements were 4.5 cm. The medial condensation was 2.1 cm lateral to the sternal border radiographically and 4.8 cm to midline in cadavers. The superior fascial condensation was 2.3 cm inferior to the clavicle radiographically and 5.5 cm by dissection. The inferior condensation was above the IMF in 82.7% of breasts by MRI and 100% of cadaveric breasts. MRI and cadaveric investigation showed similar patterns of breast tissue fascial condensations relative to standard breast boundaries. Breast skin flap thickness was greater peripherally (MRI: 11.5 mm, cadaver: 11.1 mm) than centrally (MRI: 6.6 mm, cadaver: 5.5 mm). Conclusions: MRI and cadaveric analysis demonstrated a close correlation between SFS and standard breast boundaries, although variations existed among subjects. Collaborating with breast oncologists and utilizing preoperative imaging to identify individual fascial condensations may enhance the camouflage of prepectoral implants after mastectomy.