The Thoracodorsal Artery Perforator flap (TDAP) flap and the Intercostal Artery Perforator (ICAP) flap are both innovative pedicled techniques in which excess skin and fat are removed from the back (TDAP) or the side of the chest (ICAP) to reconstruct all or part of the breast or axilla. Most commonly, the TDAP flap or ICAP flap is used in the following situations:
- Partial breast defects
- Hydroadenitis suppurativa of the axilla
- Contraindication for microvascular free flap due to medical comorbidities
- Preference for use of back fat and skin due to excess tissue
In both cases, the scar is located in the back or on the side of the chest. The difference between the TDAP and the ICAP flap is the size of the flap and the choice of blood vessels that nourish the flap tissue.
The TDAP flap is nourished by the thoracodorsal artery and vein, which supplies the latissimus dorsi muscle on the back. Obtained from the same area of the back as the more common latissimus dorsi flap, the TDAP flap is different because the TDAP is a perforator flap so that it completely preserves the muscle. The TDAP flap is composed of skin and fat that is rotated from the upper back to a position on the chest wall or axilla for use in breast reconstruction or wound coverage. Since the TDAP flap is rotated and kept on its vascular "pedicle" without having to divide and reattach blood vessels, an operative microscope is not needed. Instead, the TDAP flap is meticulously dissected under high-powered loupe magnification. Since no muscle is sacrificed, there is usually less postoperative pain. Most patients only require one night of hospitalization. the muscle function is preserved. Unfortunately, these flaps are not widely offered as an option to women undergoing breast reconstruction.
Depending on a woman's body shape, many women may have enough tissue on the upper back to enable the surgeon to use TDAP flaps alone for breast reconstruction after mastectomy. For women without adequate back tissue, TDAP flaps can be an excellent way to supplement an existing breast reconstruction with additional volume without the need for breast implants or other kinds of flaps. TDAP flaps can also be used as an alternative to implants in the correction of tubular beast deformity and as an option for women who want to undergo breast augmentation using their own tissue. The scar that results from TDAP flaps can generally be placed horizontally along the bra line so that it can be covered up by a bra.
The ICAP flap is nourished by the intercostal artery perforator, which supplies the muscle between the ribs. The tissue for the ICAP flap is taken from the skin and fat on the lateral chest wall under the arm, next to the breast. Like the TDAP flap, the ICAP is a pedicled flap, meaning that the blood supply stays connected so that there is no need for an operative microscope. The ICAP flap is also a perforator flap, which means that no muscle is sacrificed. The ICAP is a smaller flap than the TDAP flap, and is used to augment the breast or to repair smaller defects.
For some women, an added benefit of the TDAP or ICAP flap is that it removes excess back or lateral chest tissue. A scar is left in the area of the donor site tissue, but it removes the fat roll in the back or lateral chest.
What is special about the back or lateral chest flaps?
The TDAP and the ICAP flaps are both pedicled flaps that require specialized care when used for breast restoration. Tiny blood vessels are carefully isolated and dissected from the muscles in the back or lateral chest, and then the tissue is rotated around while preserving the blood vessels and muscle. While the initial investment of surgical time and effort is greater than with traditional procedures that sacrifice the muscle, the reward of preserving the muscle is decreased morbidity. Multiple studies have indicated that traditional latissimus dorsi flaps that sacrifice the muscle can lead to increased weakness that makes it difficult to swim or climb ladders.
We believe it is very important to have a tight, cohesive team that works together safely and efficiently. In our practice, breast restoration with the TDAP or ICAP flap is performed by two experienced board-certified microsurgeons with specialized expertise. We often obtain preoperative imaging of the blood vessels to map out the surgical plan before the operation. In our hands, the average TDAP or ICAP flap breast reconstruction takes about 3-4 hours for a unilateral reconstruction and 4-6 hours for a bilateral reconstruction.
Postoperatively, the flaps are monitored overnight while the patient is in the hospital. Patients are allowed to get out of bed, walk, and eat anything they want postoperatively. Most patients stay in the hospital one night. Drains are placed in the reconstructed breast(s) and the donor site. At home, daily drain output needs to be measured, and most drains are removed in 1-2 weeks. Patients should take at least 2 weeks off of work, and avoid heavy lifting and strenuous activities for 4-6 weeks. Most patients are fully recovered without any physical limitations in 6-8 weeks.