The Anatomic Features and Role of Superficial Inferior Epigastric Vein in Abdominal Flap

Abstract

In lower abdominal flap representing transverse rectus abdominis musculocutaneous (TRAM) flap or deep inferior epigastric perforator (DIEP) flap, superficial inferior epigastric vein (SIEV) exists as superficial and independent venous system from deep system. The superficial venous drainage is dominant despite a dominant deep arterial supply in anterior abdominal wall. As TRAM or DIEP flaps began to be widely used for breast reconstruction, venous congestion issue has been arisen. Many clinical series in regard to venous congestion despite patent microvascular anastomosis site were reported. Venous congestion could be divided in two conditions by the area of venous congestion and each condition is from different anatomical causes. First, if venous congestion was shown in whole flap, it is due to the connection between SIEV and vena comitantes of DIEP. Second, if venous congestion is limited in above midline (Hartrampf zone II), it is due to problem in venous midline crossover. In this article, the authors reviewed the role of SIEV in lower abdominal flap based on the various anatomic and clinical studies. The contents are mainly categorized into four main issues; basic anatomy of SIEV, the two cause of venous congestion, connection between SIEV and vena comitantes of DIEP, and midline crossover of SIEV.

Keywords: deep inferior epigastric perforator flap; superficial inferior epigastric vein; transverse rectus abdominis musculocutaneous flap; venous congestion.

Fig. 1

General configuration of superficial inferior epigastric vein: ( A ) typical, symmetric configuration, ( B ) asymmetric configuration, and ( C ) large inverted V-shaped midline crossover arborized below inguinal ligament; arrow heads depict prominent midline crossovers.

Fig. 2

Venogram in half transverse rectus musculocutaneous flap shows communication between superficial inferior epigastric vein and vena comitantes of deep inferior epigastric artery. Right picture shows sagittal-cut venogram of yellow rectangular area in left hemiabdomen specimen. Communicating vein is anastomosed with vena comitantes of deep inferior epigastric perforator (VC-DIEP) via polygonal venous network. Red arrow depicts VC-DIEP. AB, ascending branch; DB, descending branch; SIEV, superficial inferior epigastric vein; U, umbilicus.

Fig. 3

Venogram shows difference of polygonal venous networks in supraumbilical area and in infraumbilical area. The distance between the bilateral superficial inferior epigastric veins is shorter in supraumbilical area and passing only one to two short polygonal venous networks is needed for midline crossing in supraumbilical area. U, umbilicus.

Fig. 4

Injection of Microfil via deep inferior epigastric perforator shows venous flow proceeding in superficial inferior epigastric vein (SIEV) which has passed through capillaries.

Fig. 5

Angiographic images acquired using soft tissue X-ray and three-dimensional computed tomographic angiography (3DCTA) from the same specimen. 3DCTA can simply show three-dimensional reconstructed image. Magnified image shows loss of fine vascular structure in 3DCTA which can be identified in soft tissue X-ray system (yellow arrow head).