Comparison of Fat Necrosis between Zone II and III in TRAM Flaps: A Prospective Study

ABSTRACT

Fat necrosis in transverse rectus abdominis musculocutaneous(TRAM) flaps is considered to be primarily affected by blood supply. Unreliability of blood supply in zone II has been claimed for years but no accurate comparison has been reported between fat necrosis in zone II and III. A prospective study about the incidences and extent of fat necrosis in zone II and III was designed, comparing relative vascularity between zone II and III. Immediate breast reconstructions after modified radical mastectomy or skin sparing mastectomy were performed in 150 consecutive patients with unipedicled TRAM flaps and 138 contralateral and 12 ipsilateral rectus muscles were used as pedicles. Twenty-one patients(14 percent) suffered from fat necrosis and 22 fat necroses were diagnosed in total. 17 fat necroses occurred in zone II, 3 in zone III and 2 in zone I. The incidence of fat necrosis in zone II was significantly higher than zone III, which was consistent with previous studies claiming poor vascularity of zone II. Therefore placing zone I and zone III medially and zone II laterally after discarding part of zone II will cause less deformity of reconstructed breast if resection of necrotized tissue is needed.