20 Omentum reconstruction of the breast
Skin preservation in the treatment of breast cancer enables breast reconstruction with autologous tissue, differing from the traditional myocutaneous flaps. Implants are often an option for these cases, but when autogenous tissue is desired and skin not required, the omentum is an excellent choice. We have used videolaparoscopic total mobilization of the omentum since 1995. It has proven to be an excellent option to reconstruct total breast volume, in reoperations of inadequate reconstructions, reconstructing the soft tissues which cover silicone prostheses, and for bilateral use in prophylactic surgery to reduce the risk of breast cancer.
Use of an omental flap to reconstruct the breast after cancer surgery was first reported by Kiricuta in 1963.1 Since then, the omentum has been widely used in reconstructive surgery to cover extensive thoracic defects associated with radionecrosis and tumor extirpation.2–13 This flap, whose main blood supply includes the gastroepiploic vessels, was initially used in breast reconstruction to cover an implant, and final coverage was obtained by skin grafting. The aesthetic result was unsatisfactory due to the final shape and quality of the skin coverage. The omentum has previously been employed by Erol14 as a pedicle to vascularize the lower abdominal skin flap, allowing its rotation into the mastectomy site. This was accomplished by a staged procedure, in which the omentum was rotated into the subcutaneous plane and allowed to grow into the subcutaneous fat of the lower abdominal panniculus. The flap was then rotated in a secondary procedure into the mastectomy defect. However, as creative as this technique was, it had the disadvantages of requiring multiple stages and potential complications and risks related to laparotomy.
Our technique was developed based on the experience of the senior author with skin-sparing mastectomy and the use of mesh support in breast surgery. This procedure follows the basic principles of breast reconstruction in an original way. First, the new breast’s volume is obtained by insetting the laparoscopically harvested omental flap, based on the gastroepiploic vessels. Breast shape is defined and supported by an internal bra consisting of synthetic mixed mesh that wraps and fixates the flap to the thoracic wall. Finally, the skin-sparing mastectomy technique offers high-quality coverage with native skin and reduced and well-positioned scars.
Later, we started using the omentum to cover silicone implants, creating a protection tissue layer underneath the skin, partially conjugating it with the pectoralis major muscle and mixed mesh, whenever required. This composition of tissues covering the mesh and the silicone prosthesis creates a structure which simulates mammary tissue and does not enable skin adherence to the muscular plane, providing good aesthetic results in the reconstruction of skin sparing mastectomy similar to those obtained in augmentation mammoplasty. This tissue structure also creates an excellent protection for the mammary prosthesis, enabling good scarring adaptation and low complication rates.
Another advance of this technique was the use of mixed mesh to partially cover and support the lower hemisphere of the silicone prosthesis, which is then sutured to the lower edge of the pectoralis major muscle and to the inframammary fold (IMF). The pectoralis major is then released on the sternal region to decrease function, avoiding lateral projection without losing coverage of the upper hemisphere of the implants. The use of omentum flap is flexible, safe, and provides several solutions. Videolaparoscopic approach is very safe, takes 60–90 min, and provides good postoperative recovery.
The following points are important when selecting patients for this procedure. The patient needs to have enough good quality skin for the reconstruction; the omentum flap and the implant will provide the new breast volume. Abdominal cavity conditions for laparoscopic harvesting must be evaluated prior to surgery. Unfortunately, it is not possible to evaluate the volume of the omentum before surgery, but with the anatomical characteristics of the patient is possible to get an idea of the amount that may be used for the reconstruction. History of previous abdominal surgery near the omentum should be considered and any impact on the integrity of the pedicle.
With the patient appropriately positioned, the abdominal cavity is inflated with CO2 until intra-abdominal pressure is 10 mmHg. A Veress needle is then inserted through the umbilicus, followed by a 0-degree fiberoptic camera. Under direct visualization, two 12-mm trocars are symmetrically inserted 6 cm from the midline and 4 cm above the umbilicus. Two accesses for the surgeon’s instruments and one for the assistant are established 4 cm caudal to the costal margin, at the level of the right midclavicular line.
The surgeon, positioned between the patient’s legs, mobilizes the omentum using a forceps and an ultrasound-assisted dissector. Metallic clips are employed for hemostasis of vessels whose diameter exceeds 1 mm. Dissections between the omentum and colon progresses from left to right exposing the posterior portion of the stomach (from the duodenum to the gastric fundus), keeping the omentum connected to the stomach by its gastroepiploic pedicles (Fig. 20.1). The left gastroepiploic pedicle is ligated using a 30-mm linear endoscopic stapler.
The omentum is exteriorized through a 5–6 cm midline incision in the upper epigastric region. The gastric branches of the gastroepiploic arcade are ligated from left to right until the right gastroepiploic pedicle is completely isolated. Extreme care must be taken when exteriorizing the flap to avoid torsion or kinking of the pedicle. The flap is then tunneled subcutaneously toward the mastectomy site (Fig. 20.2). Aponeurosis is closed in the epigastric region using 0 Prolene sutures, leaving a 2 cm opening for the flap’s pedicle. At this moment, the pedicle must be checked once more for kinking, compression, or torsion. The subcutaneous layers and skin are finally closed using Monocryl 4-0 sutures.
Immediate post-mastectomy reconstruction is performed by placing the omental flap anterior to the pectoralis major muscle and fixating it with Monocryl 4-0 sutures. Factors such as the breast’s volume, limits, and projection are determined, and more volume is concentrated in the inferior hemisphere.
The synthetic mesh is then placed over the omentum to shape and support the new breast. Fixation of the mesh to the pectoralis major muscle is carried out using titanium clips or interrupted nylon 4-0 sutures (Fig. 20.3). Skin closure is performed using a Mersilene 3-0 purse-string suture to completely cover the new breast cone, define its limits and complete the shaping process. Suction drains exteriorized at the level of the anterior axillary line are kept for 5 days or until drainage is <20 mL/day. Figure 20.4 shows the preoperative condition for comparison purposes and Figure 20.4B demonstrates the immediate postoperative shape created.