Anatomic and physiological fundamentals for autologous breast reconstruction

Abstract

The success of autologous tissue transfer is reliant on adequate blood supply and as we endeavour to tailor our reconstructive options through our flap choices and design. Autologous breast reconstruction has made substantial progress over the years and the evolution of refinements over the last 30 years has allowed flaps to be based on specific perforators. The ultimate goal of breast reconstruction following mastectomy is to match optimal tissue replacement with minimal donor-site expenditure. In parallel surgeons will seek ways to ensure safe flap design and harvest while maintaining predictability and reliable tissue perfusion. Better understanding of the vascular anatomy and physiology of the cutaneous circulation of soft tissues, and that of patterns of blood flow from individual perforator has provided insight to advance perforator flap harvest and modifications in flap design. The aim of this article is to review the principles of blood supply and flap design exemplified through common flaps used in autologous breast reconstructive surgery, to better understand approaches for safe flap harvest and transfer of well perfused tissue.

Keywords: Autologous reconstruction; anatomy; blood supply; breast reconstruction; flap design; free flaps; pedicled flaps; perforasome; perforator flaps; vascular territory.

Figure 1

Communication between adjacent perforators through direct linking vessels and indirect communications via the subdermal plexus. (Permissions requested for Re-print) (6).

Figure 2

Illustration to demonstrate the direction of principal linking vessels and the axiality of flow from perforators dependent on anatomical site. (Permissions requested for Re-print) (6).

Figure 3

Illustrative example of DIEP flap for breast reconstruction, with preservation of the underlying rectus muscle and postoperative reconstruction following inset and anastomosis to the internal mammary vessels. DIEP, deep inferior epigastric perforator.

Figure 4

Location of dominant perforators in DIEP flap harvest, identified as a “hot spot” in the lower abdomen. DIEP, deep inferior epigastric perforator.

Figure 5

Representation of the traditional Hartrampf zones of perfusion for TRAM flaps which has still been used with reference to DIEP flap harvest. TRAM, transverse rectus abdominis myocutaneous; DIEP, deep inferior epigastric perforator.

Figure 6

Micro computed tomographic studies following a single perforator injection to demonstrate the presence of direct linking vessels in a DIEP flap and recurrent flow via the subdermal plexus, with communication with adjacent perforators. DIEP, deep inferior epigastric perforator.

Figure 7

Intraoperative use of indocyanine green fluorescence laser angiography and quantitative analysis of flap physiology in a left hemi-DIEP flap. Marker to show position of medial row perforator and colour map overlay applied. DIEP, deep inferior epigastric perforator.

Figure 8

Alternative perforator zones of perfusion territories based on a medial row perforator in the lower abdomen in DIEP flap harvest. DIEP, deep inferior epigastric perforator.

Figure 9

(A) Intraoperative clinical recognition of venous congestion following hemi-DIEP flap harvest prior to flap transfer, provides a good indication to augment venous drainage with the SIEV or the MSIEV, which have both been dissected out; (B) dissection of the SIEV and MSIEV during DIEP flap harvest. DIEP, deep inferior epigastric perforator; SIEV, superficial inferior epigastric vein; MSIEV, medial superficial inferior epigastric vein.

Figure 10

DIEP donor site closure using progressive tension sutures and limited dissection of the abdominoplasty to preserve the lateral perforators of the anterior abdominal wall. DIEP, deep inferior epigastric perforator.

Figure 11

(A,B) Intraoperative preoperative marking of a “tri-lobed” skin paddle design in TUG myocutaneous flap for breast reconstruction. TUG, transverse upper gracilis.

Figure 12

Preoperative marking of “S” shaped skin paddle design for TUG myocutaneous flap in breast reconstruction. TUG, transverse upper gracilis.

Figure 13

Cadaveric injection study of the perforator territory of the dominant pedicle of the gracilis myocutaneous flap. (A) Medial thigh flap harvest from a fresh frozen cadaver and demonstration of dominant pedicle; (B) iodinated contrast injection study demonstrating the cutaneous vascular territory of the main pedicle extends more posteriorly in the thigh.

Figure 14

(A) Donor site resultant scar at 6 weeks post procedure following TUG flap for breast reconstruction using a transverse skin paddle; (B) preoperative (left) and postoperative (right) results following TUG breast reconstruction. TUG, transversus upper gracilis.

Figure 15

Potential orientation of skin paddles in a muscle sparing LD flap reconstruction based on the descending branch of the thoracodorsal artery. LD, latissimus dorsi.

Figure 16

Preoperative planning for LD breast reconstruction and orientation of the skin paddle along natural skin tension lines and maximal size designed following the pinch test in a high pinch BMI patient (A) and a slim patient (B). LD, latissimus dorsi.

Figure 17

(A,B) Illustration of surface anatomy of MSLD flap and design of skin paddle, and flap harvest; (C) intraoperative photograph following MSLD flap harvest prior to flap transfer and inset. MSLD, muscle sparing latissimus dorsi.

Figure 18

(A) Preoperative and (B) postoperative following MSLD for a lumpectomy contour defect of the left breast. MSLD, muscle sparing latissimus dorsi.

Figure 19

The intraoperative dissection of the PAP flap for breast reconstruction (left image) and the identification of large perforators on preoperative imaging (center image); intraoperative picture of the flap raised but not transferred, demonstrating the posterior position of the donor site scar. PAP, profunda artery perforator.

Figure 20

(A) High resoltion CTA following injection of a posterior midline perforator of the PAP and demonstration of bi-directional flow to the medial and lateral aspects of the upper posterior thigh flap in cadaveric studies; (B) CT imaging of a poosterior thigh flap with a proximal profunda artery perforator injected with iodinated contrast and demonstration of the individial perforator vascular territory; (C) a perforator injected in the posterior midline of the thigh with an extended territory towards the lateral thigh. CTA, computed tomographic angiography; PAP, profunda artery perforator.

Figure 21

Illustration of anatomical landmarks of the superior gluteal perforator flap for autologous breast reconstruction. SGAP, superior gluteal artery perforator; IGAP, inferior gluteal artery perforator.