April 16, 2018 The Skinny On Fat Grafting Jason R. Bailey, M.D. Breast enhancement and reconstruction are some of the most common procedures a plastic surgeon performs. While most people are familiar with use of breast implants, saline & silicone, physicians have also been using the patient’s own tissue, termed autologous tissue, for cosmetic enhancement and breast reconstruction for over 100 years. In 1895, Dr. Czerny performed the first breast reconstruction when he transplanted a benign fatty growth, also termed a “lipoma” from the dorsal flank to the breast. Unfortunately, the procedure was unsuccessful and initially at the time, autologous options for Breast reconstruction were abandoned. We now know that large pieces of tissue such as fat lipomas are unable to acclimate in a new area unless there is adequate blood flow to penetrate the transplanted tissues to allow for transfer of nutrients to the fat cells. The more modern history of using of autologous fat for cosmetic enhancement of the breast has been performed since the 1950s. This technique was largely relegated to a small number of providers given concerns with cancer screening with use of mammography following the procedure. The technical challenge of differentiating the changes seen in the imaging of a breast being post-surgical and normal, and not concerning for cancer, was historically difficult to differentiate with findings on the mammogram indicative of early formation of cancer. This is because the normal healing of transplanted fat resulted in calcified tissue similar in appearance on plain film mammography to cancer calcifications. The story of breast reconstruction and augmentation with autologous fat continued then accelerated in the last decade. This was in large part due to advances made with the transition to digital mammography from plain film mammography, and then enhanced by 3-dimensional tomography, and decrease cost associated with breast MRI. These modern imaging modalities now allow radiologists and surgeons to more accurately differentiate normal post-surgical changes from the surgical transfer of fat compared to patients who had concerning findings warranting additional workup from precancerous or cancerous lesions to the breast. In addition, we now have a more fundamental scientific understanding of the physiology of fat and its actions when it has been transferred from one body part to another. Sophisticated molecular laboratory studies now allow for the honing of techniques to accomplish better results and retention of the transferred fat. Surgical Techniques have shifted towards harvest and transfer of smaller lobules of fat which are harvested in a low and consistent pressure system and kept outside the patient’s body for a minimal amount of time. Uniform redistribution within the breast tissue by microinjection and “threading” techniques allow for maximal blood flow to support the transplanted fat, thus achieving better take and enhancement of the recipient breast. Understanding of the amount of fat which is safe to transfer is often dictated by the breast envelope of tissue. I like to think of it as a shopping bag. There is a fixed end point of maximal fat transfer volume which each individual breast can accommodate. We use the measurement of venous pressure. This value has been appreciated as an endpoint of transfer to the breast as staying under the peak Venous pressure allows for outflow of blood from the transplanted breast so that used nutrients are still able to circulate out of the tissue. This venous pressure is affected by not only volume of fat transferred but also the breast “envelope”. Patients who are dense breasted, younger and without significant skin envelope stretch, which would be a patient who is typically nulliparous or having had no children, would accommodate much less fat than a multiparous or mother who has breastfeed and had previous breast engorgement, and stretching of the skin envelope. Also Menapausal age coincides with decreased circulating estrogen and the convergence of the breast soft tissue from glandular to fatty tissue, which is able to accommodate 2 to 3 times the amount of fat transfer as a younger more dense breast glandular tissue. To monitor this during surgery, we used sophisticated measuring techniques for internal tissue pressures during the fat transfer to measure and enhance the take of the fat which we transfer to give us a hard endpoint of volume transfer, to avoid unwanted consequences such as degradation and dissolving of the transferred fat, also termed fatty necrosis which can lead to lumps and bumps along with decreased aesthetic appeal. A further advancement in our ability to perform fat grafting procedures for breast reconstruction and cosmetic is the use of negative pressure expansion. This is accomplished with an external device termed BRAVA which is a large suction dome with silicone padding which is connected to a well-known pump brand name, Medela of Switzerland. Many women are familiar with Medela as they make a broad range of breast pumps for milk obstruction during the lactation period. The pump use is a slightly different pressure than the breast pump but the effect of the negative pressure on the breast is that it promotes mild swelling and engorgement of the breast creating a virtual anatomical space along with enhancement of blood flow. In anticipation for a transfer of fat to the breast, patients who are proper candidates for expansion will utilize this device prior to surgery for one week and following surgery for 3 days, to allow greater amounts of fat volume to be transferred, thereby improving the “take” or engraftment of the transferred fat within the breast tissue. Certainly, another advantage of using autologous tissue to enhance the breast is the benefit of allowing liposculpting of the body. Many times, the silhouette of a woman is enhanced not only by breast size and shape but also in contour of the abdomen and flanks as it relates to the size and shape of the breast. As age continues truncal obesity due to hormonal changes is common and surgical liposculpting with during the harvest of the fat improves the silhouette and enhances the overall form of the body and shape to a more feminine beautiful appearance. Often, the amount of fat harvested for transfer is 1/2 to 1/5 the amount, which is ultimately taken to allow the wanted improvements in the waistline and flanks. Many patients will ask why fat transfer to the breast is not more of a mainstream treatment. There are various reasons for this. Currently, we are undergoing a large multinational registry for the transfer patients of the breast. There were companies which invested in technology to facilitate this surgical technique by adding enhanced fat along with the regular liposuction fat, by taking a portion of the harvested fat and putting it through a digestion and extraction. This created adipose-derived regenerative cells which were made up of the very small cells which had property similar to stem cells. The regenerative cells, which are present in fat tissue around the capillaries are harvested during the liposuction process and extracted with an automated system. The FDA had initial concerns that involved concentrating these “stem” type cells with potential to expand the various tissue types and introducing them to the breast. It was felt that the presence within the breast of these “stem” type cells, which may be placed near a microscopic precancerous beast lesion may accelerate the growth of that precancerous lesion. This led to a hold from the FDA in utilization “adipose derived regenerative, or “stem” cell concentration” technology. Interestingly, it has been found that no appreciable difference exists by adding the use of adipose-derived “stem” cells to the regular liposuction fat used in the transfer of fat for breast enhancement. The second reason this technique is not widely distributed is because of the economics of aesthetic surgery. While patients come in all shapes and sizes, almost all have the adequate fat needed for transfer to the breast as the relative amount of fat needed to enhance breasts is rather small compared to the amount available in the average body even in a thin individual. In addition, there is no significant industry advantage to the use of patients own tissue for breast reconstruction as this negates the use of much more expensive industry options. For comparison, the use of silicone breast expanders, dermal replacement products to use the slings in the lower portion to cover the expanders following mastectomy and then change out of the expander for permanent implants can gross over 20,000 USD per surgery. In comparison, the total cost of disposable products for transfer the of fat often run under $1000 per patient. Therefore, there exists no organized advertising effort on the part of industry to push fat grafting to the breast, and educating patients about this alternative is left in the hands of doctors to offer educate patients about their suitability for this surgical option. When consulting with my patients, I speak to them about all procedures available. Different patients have different desires. For some patients, a more natural appearing enhancement of the breast is sought, in others a more pronounced and full upper pole of the medial upper portion of the breast is seen as the desired décolletage. Tailoring the procedure to the patient and the patient desires is the job of a plastic surgeon. Other advantages of fat grafting to the breast are the longevity of the procedure, given that there is no artificial product within the patient, long-term complications are typically avoided which is not the case with use of artificial implants. There is less chance that revision surgery may be needed to address the dreaded complication of silicone breast implants, capsular contracture. Artificial pulling up of the breast, and asymmetry are less likely with use of autologous fat. For breast reconstruction, positives of using autologous fat are that sensation is better preserved to the nipple. This is because the breast area nerves are able to grow from deep to superficial following mastectomy, as they do not have a mechanical barriers such as a large breast silicone implant for which they cannot grow through. Cost on average for breast reconstruction with autologous fat are lower and traditional methods used given that expensive implants and prolonged microvascular surgical time is not required. Typically speaking, autologous fat transfer for breast reconstruction does entail 3 to 4 procedures but this is less than the average number of procedures needed for implant and expander. In comparison with free microvascular transfer such as deep inferior epigastric perforator “DIEP” flaps, breast reconstruction with liposuction autologous fat often has an equivalent number of surgeries but the surgeries are outpatient, the patients go home the same day and are able to return to work typically in 3 to 4 days as opposed to 5 to 6 weeks with DIEP microvascular reconstructions. Also pain following fat transfer procedure is often less severe, given that there is no encroachment on the ribs which is needed in DIEP flaps. I hope this has been informative discussion. As a board certified plastic and reconstructive surgeon, the members of our society pride ourselves in continuing to innovate and utilize new techniques to enhance the ability of the surgeon to reconstruct, remake, remote, and enhance our patients personal appearance in an attempt to repair damage caused morphologically from cancer or patient’s desires to enhance themselves for feeling of confidence and fullness. While one technique is not a fix-all for all patient conditions, autologous fat transfer continues to evolve as a tool and has increasingly become more popular as advancements and technology are more available to the surgeon. Speak to your surgeon about the background and comfort level of autologous fat when exploring options for breast reconstruction and enhancement.