Lateralising paraumbilical medial row perforators: Dangers and pitfalls in DIEP FLAP planning: A systematic review of 1116 DIEP flaps

SummaryBackgroundThe DIEP flap remains the gold standard for autologous breast reconstruction. Recently, the ‘perforasome concept’ has advanced our understanding of DIEP flap physiology and planning. This study highlights a patient sub-population that produces anomalies to the perforasome hypothesis: those with paramedian, paraumbilical perforators.MethodsOperation notes and pre-operative CT angiograms from 1116 consecutive DIEP flaps were reviewed retrospectively. Patients with paramedian, paraumbilical perforators (n = 153) were contrasted against a control group whose perforators were not paraumbilical (n = 963). Further sub-group analysis was performed within the study group, comparing paraumbilical perforators that held a lateral course within the flap (n = 25) versus those that held a medial course (n = 128).ResultsRates of post-operative DIEP flap partial necrosis was greater in the study population compared with the control group (6.54% vs. 3% p = 0.032). When analysis was made contrasting paraumbilical perforators that held a lateral course in the flap versus perforators that held a median course, flap necrosis was significantly greater in those with a lateral course (24% vs. 3.13%).ConclusionThe perforasome concept has improved our understanding of perfusion from perforators in DIEP flaps. However when the umbilicus presents a physical barrier to blood vessel passage resulting in lateralizing paraumbilical medial row perforators it appears an exception to the “perforasome” rule. Our experience suggests that when a paraumbilical perforator is harvested, a hemi-flap is safe but caution should be exercised when further volume is needed from the contralateral side.