Improving the Safety of DIEP Flap Transplantation: Detailed Perforator Anatomy Study Using Preoperative CTA

Abstract

Background: Deep inferior epigastric perforator and muscle sparing transverse rectus abdominis muscle flaps are commonly used flaps for autologous breast reconstruction. CT-angiography allows to analyse the perforator course preoperatively. Our aim was to compare the different aspects of perforator anatomy in the most detailed study. Methods: CT-angiographies of 300 female patients with autologous breast reconstruction of 10 years were analysed regarding the anatomy of the deep inferior epigastric artery and every perforator. Results: Overall, 2260 perforators were included. We identified correlations regarding the DIEA branching point and number of perforators and their intramuscular course. The largest perforator emerged more often from the medial branch of the DIEA than the smaller perforators (70% (416/595) vs. 54% (878/1634), p < 0.001) and more often had a direct connection to the SIEV (large 67% (401/595) vs. small 39% (634/1634), p < 0.01). Medial row perforators were larger than the laterals (lateral 1.44 mm ± 0.43 (n = 941) vs. medial 1.58 mm ± 0.52 (n = 1304) (p < 0.001)). The larger and more medial the perforator, the more likely it was connected to the SIEV: perforators with direct connection to the SIEV had a diameter of 1.65 mm ± 0.53 (n = 1050), perforators with indirect connection had a diameter of 1.43 ± 0.43 (n = 1028), perforators without connection had a diameter of 1.31 mm ± 0.37 (n = 169) (p < 0.001). Medial perforators were more often directly connected to the SIEV than lateral perforators (medial 56% (723/1302) vs. lateral 35% (327/941), p < 0.001). A lateral perforator more often had a short intramuscular course than medial perforators (69% (554/800) vs. 45% (474/1055), p < 0.001), which was also more often observed in the case of a small perforator and a caudal exit of the rectus sheath. Conclusion: The largest perforator emerges more often from the medial branch of the DIEA and frequently has a direct connection to the SIEV, making medial row perforators ideal for DIEP flap transplantation.

Keywords: CTA; DIEP flap; MS-TRAM flap; autologous breast reconstruction; perforator.

Figure 1

Perforator and DIEA mapping using computed tomographic angiography (CTA) in transversal (A), sagittal, (B) and coronar (C) view (#: connection to SIEV, +: intramuscular course, *: branching of DIEA).

Figure 2

Medial row perforators have a statistically significantly larger diameter than lateral row perforators. *** = p ≤ 0.001.

Figure 3

Boxplot of the diameter and different SIEV connections. SIEV = superficial inferior epigastric vein. The diameter of the perforator had a significant influence on the connection to the SIEV. The different connection types varied significantly among themselves. *** = p ≤ 0.001.

Figure 4

Absolute counts of different SIEV connection types regarding exit of the recuts sheath. Perforators close to the umbilicus were more likely connected to the SIEV.

Figure 5

Medial row perforators were more often directly connected to the SIEV compared to lateral perforators. *** = p ≤ 0.001.

Figure 6

Medial row perforators had a more equally distributed intramuscular course, whereas lateral perforators more often had a short intramuscular course. *** = p ≤ 0.001.

Figure 7

Distribution of the largest perforator versus the remaining perforators regarding the branch of the DIEA.

Figure 8

The largest perforator was significantly more often directly connected to the SIEV compared to the remaining perforators, whereas the remaining perforators were more often indirectly connected or without any connection. *** = p ≤ 0.001.