Preoperative assessment of the superficial epigastric venous system in large DIEP flaps for breast reconstruction: The role of the midline venous crossover in SIEV selection.

Abstract

Venous congestion remains a clinically relevant determinant of morbidity in deep inferior epigastric perforator flap breast reconstruction, particularly when large flaps are needed and extend beyond the abdominal midline. This study evaluated whether preoperative computed tomography angiography grading of superficial epigastric venous midline crossover could guide superficial inferior epigastric vein drainage when additional venous outflow was required. In this retrospective single-centre series, 200 consecutive delayed unilateral, three-zone, single-pedicled deep inferior epigastric perforator flap reconstructions were analysed. Superficial venous communication was classified on computed tomography angiography as Grade I, indicating poor crossover, or Grades II-III, indicating good crossover, and findings were correlated with intraoperative congestion, superficial inferior epigastric vein anastomosis laterality, and postoperative outcomes. Good crossover was identified in 120 flaps (60.0%) and poor crossover in 80 (40.0%). Additional superficial inferior epigastric vein anastomosis was required in 59 cases (29.5%). Crossover grade did not predict the overall need for additional venous drainage (p=0.841), confirming that this decision remains primarily intraoperative. However, crossover grade strongly predicted drainage laterality: Grade I anatomy was predominantly managed with contralateral drainage (20 contralateral vs 2 ipsilateral), whereas Grades II-III favoured ipsilateral drainage (28 ipsilateral vs 9 contralateral). Among drained flaps, postoperative venous congestion was not associated with anastomosis laterality (p=1.00). Preoperative assessment of superficial midline venous crossover should therefore be considered a planning tool for selecting the most appropriate superficial drainage side, rather than a predictor of whether additional venous drainage will be required.