What is a DIEP Flap and how does it differ from a free TRAM flap?

What is a DIEP Flap and how does it differ from a free TRAM flap?
A DIEP, or deep inferior epigastric artery perforator flap, represents an important step in the evolution and refinement of the TRAM or transverse rectus abdominis myocutaneous flap. Both the free TRAM and DIEP flaps are microvascular reconstructions, meaning that the tissues used to reconstruct the breast are separated from the abdomen and then reattached at the breast. The big advantage of both of these microvascular reconstructions is that they spare more muscle tissue than other forms of breast reconstruction that do not use implants and provide more freedom for the surgeon to shape and position the breast.

The free TRAM flap still requires that a small amount of abdominal muscle tissue (rectus abdominis) is taken with the flap while the DIEP flap does not take this muscle tissue at all. In some cases, the amount of muscle tissue taken with the free TRAM is so tiny that the patient would never realistically notice its loss. The DIEP flap has been associated with less post-operative pain and a lower risk of abdominal wall weakness in some studies compared with TRAM flaps. The free TRAM flap has been associated with less fat necrosis (hard lumps of fat that develop in the reconstructed breast because of poor blood supply) compared with the DIEP flap.


Here, the pedicled TRAM flap – outlined in green – uses an entire side of the rectus abdominis muscle to provide blood flow to the abdominal skin and fat used to reconstruct the breast. The muscle-sparing free TRAM flap uses only a fraction of the rectus abdominis muscle as denoted in yellow. The DIEP flap, when doable and indicated, preserves the rectus abdominis muscle altogether as outlined in purple.

DIEP flaps are performed when:

  1. Blood vessel anatomy favors a DIEP flap – The surgeon will look for suitable branches of the deep inferior epigastric artery called perforators to determine if this is possible. A combination of exploration in the operating room and possibly a special CAT scan (CT angiogram) before surgery are used to decide this.
  2. The body mass index (BMI) is ≤30.
  3. A small-to-moderate flap is required.

The muscle sparing free-TRAM is performed when:

  1. Blood vessel anatomy favors a muscle-sparing free TRAM.
  2. The BMI is ≥30.
  3. A large flap is required. Of all of the forms of reconstruction using a patient’s own tissues, the free TRAM flap allows the largest amount of tissue to be taken with the least chance of tissue loss or fat necrosis.
  4. Free-TRAM may be safer in a smoker than a DIEP flap.
DIEP Flap Video

New Technologies and Techniques That Have Advanced Breast Reconstruction
At West County Plastic Surgeons, we have taken advantage of several new techniques and medical advances to improve outcomes for our patients. These include microsurgery, fat transfers, alloderm, direct-to-implant breast reconstruction and the Spy device. To learn more about these technologies, please read on:

1. Microsurgery. Microsurgery is an advanced area of plastic and reconstructive surgery whereby microscopes are required to reattach tiny blood vessels and nerves. Microsurgery has had a huge positive impact on breast reconstruction since it provides the plastic surgeon a tremendous amount of flexibility in terms of what tissues can be used from the body to reconstruct the breasts and frequently allows the plastic surgeon to reconstruct a larger breast. Microsurgery may be the only option to reconstruct the breasts in patients whose reconstructions have been unsuccessful with other more conventional forms of reconstruction like breast implants.

The DIEP (deep inferior epigastric artery perforator), SIEA (superficial inferior epigastric artery), free TRAM (free transverse rectus abdominis myocutaneous), TUG (transverse upper gracilis myocutaneous), ALT (anterlateral thigh) and SGAP (superior gluteal artery perforator) flaps require microsurgery for breast reconstruction.


DIEP Flap Video



TUG Flap Video

Microsurgical breast reconstruction requires not only a plastic surgeon trained in microsurgery, but also a hospital with the resources and experience to perform these cases efficiently and to provide excellent aftercare. Microsurgery may be the only reasonable option in certain cases to achieve a breast reconstruction, but it is important to remember that it is not an option for every patient. Every patient considering this procedure needs to be evaluated in person by a plastic surgeon experienced with these techniques.

2. Fat Transfers. Fat transfers have been added to improve our results with breast reconstruction. Fat transfer is one of the hottest topics in plastic surgery because of its potential benefits, but also because it is controversial. At West County Plastic Surgeons of Washington University, we strive to provide a balanced assessment of all new technologies and techniques.

Currently, we are using fat transfers primarily as a “touch up” procedure after breast reconstruction with implants or your own tissues. Fat is usually harvested from your abdomen, flanks or thighs. The fat cells are separate from the body fluids that bathe them using a technique called centrifugation. The fat cells are isolated and injected into areas that need more volume in tiny packets through tiny incisions that are usually 2-3 mm long. In this way, your own fat may be used to fill contour dips or camouflage areas of implant rippling.


Fat transfers have also been used to reconstruct defects following lumpectomy. In this case, patients need to be cancer-free for over a year after receiving radiation and need to be getting careful monitoring afterwards to be considered for fat transfer. Reconstruction of the entire breast following mastectomy with fat transfers may also be possible but is associated with smaller volume breast reconstructions, has not been rigorously studied, and unlike other procedures, is not covered by insurance.

3. Alloderm. Alloderm is a medical device known as an acellular dermal matrix. It is derived from human skin from which cellular elements have been removed. It is treated with antibiotics to reduce the risk of infection. It can be used to reconstruct the lower component of a breast implant pocket, thereby providing additional support and control of the shape of the reconstruction while eliminating the need to manipulate other muscle or connective tissue that can cause pain, affect function or compromise the aesthetic positioning of a reconstructive breast implant. Alloderm is a tool that is usually used in conjunction with tissue expander or direct-to-implant based breast reconstructions.

4. Direct-to-implant breast reconstruction. A direct-to-implant breast reconstruction may enable a patient to undergo mastectomy and reconstruction with a single general anesthetic. Patients who are eligible for this procedure are typically non-smokers, have moderate-sized breasts, and require a prophylactic mastectomy or have DCIS or a low-stage breast cancer that does not involve the nipple or areola. The patient’s general surgeon needs to agree that a skin or nipple-sparing mastectomy is acceptable, and the patient must still be prepared that the plastic surgeon may still choose to do a tissue expander instead of a direct-to-implant reconstruction during surgery. Alloderm is used to support the breast implant with the direct-to-implant technique.

A direct-to-implant reconstruction can be combined with a nipple-areola sparing mastectomy. When these techniques are options, the patient can preserve their own nipple and areola, retain improved projection of the breast, and have a surgical scar that is well-concealed under the breast.


Click here to review photos of a patient with direct-to-implant breast reconstruction.

5. SPY Intraoperative Angiography. The SPY device is a new technology that allows the plastic surgeon to evaluate blood flow in the reconstructed breast during surgery. A non-toxic dye called indocyanine green (ICG) is administered with the patient under anesthesia. The ICG dye binds to proteins in the blood. So, if the flap has blood flow, the ICG dye – which is harmless – will get into the flap. Then, an 806 nm laser on the SPY device energizes the ICG, which in turn releases energy that can be picked up by sensors on the SPY device. In this manner, the SPY is used to image blood flow in the reconstructed breast tissue. This information can be used to help plan the surgery and also helps to tell the surgeon what tissues from the reconstruction can be safely kept to minimize complications after surgery. A delayed SPY image can also be taken to ensure not only that new blood is getting into the flap, but also that old blood is flowing normally out of the flap. Patients with allergies to iodine or shellfish are allergic to indocyanine green and are therefore not candidates for the SPY device.

A schematic diagram of the SPY intraoperative angiogram procedure is depicted here.

SPY Images

This video shows a real time image of a bilateral DIEP flap performed by West County Plastic Surgeons being imaged by the SPY device to demonstrate normal blood flow. In this black-and-white image, black represents no blood flow and the increasingly bright white color denotes blood supply in the flap reconstruction.

SPY of DIEPS Video
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