Background: There is an ongoing debate about the reliability of various lower abdominal flaps for breast reconstruction. The authors evaluate in vivo perfusion of these flaps to objectively determine which techniques and which skin island zones had better perfusion.
Methods: A prospective study was performed on 77 single-pedicle breast reconstructions [pedicled transverse rectus abdominis muscle (TRAM), n = 22; muscle-sparing free TRAM, n = 37; deep inferior epigastric perforator (DIEP), n = 18]. Perfusion was measured intraoperatively using indocyanine green angiography following flap harvest and before transfer. Flow quantification was performed at 12 standardized data points in each of the four zones of the skin island. Patient risk factors for flap ischemia were assessed, perfusion was quantified, and comparisons were made between the various flaps and between zones.
Results: Mean perfusion was significantly higher in the 37 free muscle-sparing flaps (24.9) and the 18 DIEP flaps (21.8) when compared with the 22 pedicled TRAM flaps (19.6) (p < 0.001). Zones I and IV had significantly higher and lower perfusion, respectively (28.4 versus 13.9), when compared with the other zones. There was no significant difference in perfusion between zones II and III (20.6 versus 21.6). Differences in flap flow were significant (p < 0.001) independent of zonal differences.
Conclusions: The authors demonstrated objectively that lower abdominal free flaps based on the inferior epigastric system have better perfusion when compared with pedicled TRAM flaps. There is no appreciable difference in perfusion between zones II and III; however, it is likely related to the perforator location and dominance. Clinical correlation between these absolute perfusion values and flap viability is required.
Clinical question/level of evidence: Therapeutic, II.