Anaesthesia
Because of the large quantities of fat required, the vast majority of patients benefit from fat transfer performed under general anaesthesia. In reconstructive breast surgery, most often, in the context of breast reconstruction after mastectomy for breast cancer, the lipomodeling is performed at the same time as the reconstruction of the nipple-areolar plate and / or contralateral breast symmetry.
Conventional prophylactic antibiotic therapy is usually prescribed intra-operatively, as we always do in the various plastic surgery procedures (a 2nd generation cephalosporin flash injection at the beginning of the procedure). There is no specific antibio-therapy prescribed because of the lipomodeling.
Local anaesthesia can only be performed for small lipomodeling, corresponding to a retouching to correct a localized residual defect.
Incisions
On the harvesting sites the incisions are made with a #15 scalpel blade. For abdominal harvesting, 4 peri-umbilical incisions are performed; one lateral incision on each side, to collect the latero-abdominal and supra-iliac fat. For harvesting from the thighs, we make an incision in the gluteal fold on each side, an incision in the middle part of the thigh, an incision in the upper iliac area and an incision on the inside of the knees. We infiltrate the area with saline containing adrenaline (1 mg adrenaline in 500 ml of saline).
On the mammary recipient site, if there are already incisions, we try to incise on it. In order to cross the transfer tunnels, it is necessary to have 2 to 3 incisions, 2 of which are in the inframammary fold, and 1 in the areola. The incisions are usually made with the cutting edge of a 18G trocar in order to limit the length of these incisions.
Fat harvesting
Recent works on fat transfer have helped to standardise the fat harvesting and transferring technique, thus limiting the hazards of each step. The improvements in the various stages of the fat harvesting and transferring allows the survival of the fat in the short, medium and long term.
The harvesting cannula is a single-use cannula, or a 3.5 mm harvesting cannula dedicated to this procedure (see Doctors section). The tip of the cannula is blunt, which can go through 4 mm incisions made with the #15 blade. The harvesting is performed with syringe in order to preserve the fat, and to avoid irregularities of the harvested areas. A 10 ml Luer-lock syringe is directly attached onto the harvesting cannula. The aspiration is performed with a moderate depression, in order to reduce the trauma of the adipocytes. A strong mechanical suction could cause damage to the adipocytes and reduce the survival rate of the adipocytes.
Some practitioners use a conventional aspiration, such as a liposuction cannula connected to a vacuum assisted device to save time, however this practice will most likely damage the fat and the results won’t be as successful. The amount of fat harvested must be large enough to account for the loss associated with centrifugation and the necessary over-correction (if it is possible) while transferring the fat.
The surgical technique is delicate and must be extremely precise and comply with the surgical principles that we recommended +++ in order to obtain the desired result. In order to perfect the morphological result, at the end of the procedure, the harvesting areas are made uniform using a 4 mm harvesting cannula. The incisions are closed with fine and fast resorption thread (fast Vicryl 4/0). A simple dressing is placed on the incision at the end of the procedure and is left in place for 5 days.
Fat processing
As the fat is harvested, the scrub nurse will process the syringes in order to centrifugate the fat: a cap is screwed onto the syringe, and the syringes are then spun in batches of 6, for 15 seconds at 3200 revolutions / min.
The centrifugation will separate the harvested fat in three layers:
- a superficial layer containing oil (oily liquid rich in chylomicrons and triglycerides) resulting from cell lysis;
- a lower layer, containing the blood residues and the serum, as well as the infiltration liquid;
- a medium layer, containing the purified fat which is the useful part of the sample. This medium layer will be transferred, the other layers are discarded (the lower layer is simply discarded by taking the cap off, the upper layer is discarded by letting oil on top of the fat flow through the top of the syringe).
The staff needs to be well organized to prepare the fat efficiently and quickly. Thanks to a 3-way valve, it is possible to transfer the purified fat in 10 ml syringes, transferring from one syringe to another.
Harvesting and processing with the Macrofill kit
For those who are fortunate enough to have the Macrofill kit (adipsculpt.com), it is mandatory to precisely follow the protocol created by the Adipsculpt company. This French company develops innovative solutions to improve the fat graft uptake. Today, the Macrofill Kit is probably the most advanced process to obtain the best results, specially for surgeons still in process to obtain good results in lipomodeling.
The Macrofill kit includes all the required elements to perform a lipomodeling with single-use cannulas dedicated to this procedure. The infiltration cannula allows to infiltrate the saline and adreanline, infiltrating the tumescent at a ratio of 1 to 1 (infiltration equivalent to the fat quantity to be harvested). The harvesting is then performed with patented 60 ml incremental syringes designed to precisely control the negative pressure during the harvesting (not to exceed 10 ml of negative pressure in the 60 ml syringe) in order to preserve the adipose tissue. The harvested fat is then washed and softly spun following the provided protocol, with a dedicated centrifuge (Adip’Spin) which allows purification of the fat without traumatizing it. The scrub nurse processes the fat while the surgeon continues to harvest.
This kit has the advantage of being single-use and combines all the elements required to ensure an optimal preparation of the fat, ensuring the preservation of the fat and an optimal graft uptake (3D studies conducted by Dr. Xavier Nelissen – Liège confirmed the high rate of fat uptake).
Once the fat is processed the scrub nurse packages the purified fat in 10ml Luer-lock syringes and the surgeon injects the fat with the disposable injection cannulas provided in the Macrofill kit.
Fat transfer
After processing the fat, we then have numerous 10 ml syringes of purified fat available. The injection of fat in the breast is directly performed with the 10 ml syringes on which are connected dedicated injection cannulas specially designed for this procedure with a diameter 2 mm, slightly longer and stronger than the injection cannulas used in the facial area due to mechanical constraints, which are more important in the breast due to the recipient tissues being firmer and more fibrous.
The incisions in the breast are performed using an 18 G trocar, which allows a sufficient incision and limits the scarring that will be punctiform and almost invisible. Several incisions must be made allowing to multiply and cross the transfer micro-tunnels. The fat is injected in a small quantity forming fine cylinders of fat, resembling “spaghetti” of fat. It is necessary to perform multidirectional micro-tunnels. The injection is performed from the deeper plane to the more superficial plane (from the ribs to the skin). It is necessary to have a good spatial vision and to form a sort of three-dimensional mesh to avoid fat zones in puddles, which would lead to a fat-necrosis. On the contrary, each micro-tunnel must be designed as being wrapped in well vascularised tissue. The injection is performed under low pressure, gently withdrawing the cannula.
It is necessary to over-correct, if the recipient tissues permit +++ (if they do not allow it, we will have to consider a second session later ++), because we must consider a resorption of about 20 to 30% of the volume transferred. We must therefore apply the rule of 140%, that is to say, we must inject 140 ml of fat when we expect to obtain 100 ml.
When the recipient tissues are saturated with fat, and they no longer accept adipose tissue, there is no point in insisting otherwise there is a risk of inducing areas of fat-necrosis +++ (respect of the principle of the recipient tissue saturation+++). It is better to perform a complementary session, which will then be much easier and can be carried out a few months later. The sutures on the breast are made using very fine and fast resorption thread (fast Vicryl 4/0), and a simple small dry dressing is set up for a few days on the breast. A Tulle-gras type dressing added if fasciotomies were performed at the same time (see this chapter).
Additional gestures
Liposuction of the inframammary fold
In some cases, for patients with a relatively fatty inframammary zone and a barely visible fold, it is useful to perform a liposuction of the inframammary region, 7 to 8 cm high in order to mark the inferno limit of the breast, and increase its projection and the definition of the inframammary fold. The liposuction is performed by making an inframammary incision, and is very effective in patients with good inframammary adiposity. This technique also makes it possible to define the V below the junction of the two inframammary folds on the inter-mammary valley.
Setting the inframammary fold
In rare cases the inframammary fold is barely visible or non-existent. We consider the inframammary fold as the foundation of the breast +++. It is then useful to create or recreate the inframammary fold using the technique of the de-epithelialized flap. This technique consists in locating the level of the inframammary fold, making a cutaneous ellipse of 5 or 6 cm wide by 2 or 3 cm high, which is de-epithelialized, then the high part of the ellipse is incised, and this de-epithelialized flap is attached to the chest wall making the inframammary fold obvious. The main advantage of this technique is to give a well-defined and well-marked inframammary fold. The disadvantage of the technique is a 5 to 6 cm scar, which is usually hidden in the inframammary fold.
In the cases where this technique is necessary, we usually start with the fixation of the inframammary fold, then we perform the lipomodeling of the breast.
Fasciotomies
During lipomodeling, fibrous areas often appear which prevent the fat transfer. In these areas it is useful to release these flanges and fibrous adhesions using the fasciotomies technique. This technique involves putting the tissues under tension, using a double hook, and sectioning through the skin “blindly”, with an 18 G needle. This cut of fibrous flanges must be done in a staged manner, in order to achieve a real mesh to accommodate the grafts of fat tissue between the mesh gaps. Be careful not to detach the area because the fat uptake would not be as good and this action could lead to devascularization at the recipient site.
The technique of fasciotomy is very effective and very powerful: on a series of 1000 cases treated with fasciotomies, we showed the effectiveness of this technique. In 1 case, we had a cutaneous cut of a few millimeters which required the establishment of two stitches. However, these fasciotomies should not be abused as this may increase the rate of fat-necrosis. The experience here is important +++ to assess the need, and the quantity of fasciotomies to perform to achieve the best result without compromising tissue engraftment, nor taking any vascular risk on the skin. These gestures of fasciotomy are interesting in almost all situations of lipomodeling, but more especially in the case of breast reconstructions with fibrous zones, particularly post-radiotherapy, the sequelae of conservative treatment +++, tuberous breasts +++, pectus excavatum ++, and Poland syndrome ++. In some cases of pure aesthetic surgery, there may also be small fibrous areas, which are useful to release by the technique of fasciotomies.
Post-operative care
On the harvesting site:
The pain on the harvesting site corresponds to those observed during a typical liposuction procedure. Patients complain of a fairly sharp pain for up to 48 hours, which can be treated with simple analgesics (pain relievers). We infiltrate diluted Naropin (ropivacaine), long-acting powerful local anesthetic after harvesting, which limits the pain of the harvesting site ++++during the first 24 hours. Moderate pains subside within a few days. There is then an uncomfortable sensitivity, which can persist for 1 to 3 months. At the end of the procedure, a simple dressing is put in place and is left for ten days. Class 1 paracetamol analgesics are prescribed for about 2 weeks.
The bruises are very marked and can persist for around 2 to 3 weeks. Postoperative edema disappears in 3 to 4 months. To promote the resorption of edema, we ask patients to perform circular self-massages of the harvesting areas. An abdominal compression belt can be recommended for one and a half months, however is not prescribed in a systematic way. In rare cases, if the edema is prolonged more importantly, then we advise to carrying out a dozen sessions of endermology (LPG, cellu-M6), or manual lymphatic drainage.
On the breast:
There are bruises that disappear within two weeks. The edema associated with the procedure disappears in about a month. The evolution of the volume is towards a progressive loss of about 20 to 30% of the volume injected, however the patient, because of the edema, can have the impression of losing about 50% because the patient sees the result the day following the intervention when the edema is maximal. The volume is stable after about 3 to 4 months. When the harvested fat is very oily (very high percentage of oil after centrifugation), the fat is then of poorer quality and the resorption may be higher, of the order of 50%, and may last longer, up to 5 to 6 months.