Fat necrosis in free transverse rectus abdominis myocutaneous and deep inferior epigastric perforator flaps.

A series of 310 breasts reconstructed by a single surgeon using free transverse rectus abdominis myocutaneous (TRAM) and deep inferior epigastric perforator (DIEP) flaps was reviewed to see if there were any differences in the incidence of fat necrosis and/or partial flap loss between the two techniques. During the study period, 279 breasts were reconstructed with free TRAM flaps and 31 breasts were reconstructed with DIEP flaps. In the breasts reconstructed with free TRAM flaps, the incidence of partial flap loss was 2.2 percent and the incidence of fat necrosis was 12.9 percent. The DIEP flaps were divided into two groups. For the first eight flaps, patients were selected using the same criteria normally used to choose patients for free TRAM flaps. In this unselected early group, the incidence of partial flap loss was 37.5 percent and the incidence of fat necrosis was 62.5 percent. Because of the high incidence of partial flap loss and fat necrosis in the first eight flaps, subsequent selection was modified to limit the use of DIEP flaps to patients who had at least one sufficiently large perforator in each flap (a palpable pulse and a vein at least 1 mm in diameter) and who did not require more than 70 percent of the flap to create a breast of adequate size. In this later (selected) group, fat necrosis (17.4 percent) and partial flap loss (8.7 percent) were reduced to a level only moderately higher than that found in the free TRAM flap group. From these data, it can be concluded that the incidence of partial flap loss and fat necrosis is higher in DIEP flaps than in free TRAM flaps, probably because the blood flow to the former flap is less robust. This difficulty can be circumvented to some extent, however, by careful patient selection. Factors that should be considered include tobacco use, size of the perforators (especially the vein), and (in unilateral reconstructions) the amount of flap tissue across the midline needed to create an adequately sized breast. If these factors are properly considered when planning the operation, fat necrosis and partial flap loss can be reduced to an acceptable level. For selected patients, the DIEP flap is an excellent technique that can obtain a successful, autologous tissue breast reconstruction with minimal donor-site morbidity. For patients who are not good candidates for reconstruction with this flap, the free TRAM flap remains a good alternative.