**5. Aesthetic buttock enhancement options**

 There are surgical and non-surgical therapies to correct deformities of the buttocks and to enhance its shape and size. The least invasive way to enhance gluteal deformities and irregularities is by injection of fillers such as poly-l-lactic acid (Sculptra by Galderma Laboratories, L.P.) which is a synthetic material that is naturally absorbed by the body over time. Sculptra® is indicated for healthy patients who are looking for correction of irregularities and small areas of atrophy. In the gluteal area is used off label since his FDA approval is for correction of facial wrinkles and deep nasolabial folds. The injection technique is considered subcutaneous to deep dermal in a cross-hatch pattern. It is recommended to ovoid overcorrection because the product is expected to gradually improve the contour deficiency after treatment of the area.

 Surgical enhancement of the gluteal region depends largely on the amount of available fat to be harvested with liposuction and fat transfer. It also depends on the degree of skin laxity of the buttocks. Liposculpture (liposuction and fat transfer) is the preferred method of buttock augmentation on those female patients how have excess amounts of fat in the lower back, waist and/or abdominal area. This technique of liposculpture is popularly known and marketed as a "Brazilian butt lift" (BBL) procedure. The necessary amount of fat harvest needed varies on a case by case basis but on average 200–1000 cc of fat is micro-grafted into each side of the buttocks. In a recent reviewed survey of 100 board certified cosmetic surgeons who perform BBLs routinely, the average was 600 cc of fat inject per side. If the patient does not have enough excess fat available and is not willing to gain weight, then gluteal silicone implants are the treatment of choice (**Figure 16**).

#### **Figure 16.**

*Gluteal implants can be a great option for patients who desire significant gluteal enhancement but has very little excess fat. However, sometime even with implants, a Hispanic patient may want additional fullness laterally that can be performed simultaneously if at least some fat is available.* 

#### **Figure 17.**

*In the massive weight loss patient with severe skin laxity, a traditional incisional butt lift is the treatment of choice. The enhancement in projection for those patients can be performed with auto-augmentation via use of a dermofatty pedicle as shown. Regrettably, it is limited to an isolated area and often additional fat injection laterally is required or implants if no extra fat source exist.* 

 In the massive weight loss patient or patients with limiting amounts of fat and severe skin laxity, a traditional incisional butt lift is on treatment of choice. The enhancement in projection for those patients may be performed with micro-fat grafting and/or silicone gluteal implants (**Figure 17**). Auto-augmentation via use of a dermofatty pedicle during a formal butt lift adds bulk and projection, but unfortunately it is limited to an isolated area and often additional fat injection laterally is required or implants if no significant fat source exist.

 The other type of patient that is often encountered is the patient that lacks projection in the gluteal region and desires an improved shape but are too thin for autogenous fat transfer. They usually have an athletic build and little to no gluteal ptosis. These patients have one option for aesthetic gluteal enhancement which is the surgical placement of a gluteal implant. Historically, one of the first ways surgeons started to augment the buttocks was with round silicone gel breast implants. However, surgeons quickly realized that breast implants were problematic in the buttock region [2]. Over the years, multiple techniques have been described for gluteal augmentation using prosthesis in three anatomical planes: submuscular, intramuscular and subfascial [3–5]. The submuscular placement is considered unfavorable because of the increased risk of injury to the sciatic nerve. This potential risk was minimized, but not eliminated, by placing the implant in an intramuscular plane. The subfascial technique virtually eliminates the morbidity of sciatic nerve injury but comes with other limitations such as a more visible and palpable implant.

### **6. Technical steps**

## **6.1 Liposculpute technique (liposuction with autologous fat grafting, "Brazilian butt lift")**

First, the fat donor sites are established. Common areas for fat harvest include, but are not limited to, the abdomen, chest, lateral thorax, waist, hips, back, arms,

 and/or thighs. For the best aesthetic outcomes, the lower back, sacrum, waist and hips are areas that are almost always treated with liposuction to narrow the waist and accentuate the curves and lower the hip/waist ratio.

Next, pre-surgical markings are preformed while the patient is in an upright position. Deep depressions or areas that need to be grafted are outlined in red and areas that need to be liposuction are marked in blue. Once the patient has been put under general anesthesia, foot pumps are applied for deep vein thrombosis prophylaxis and 2 g of cefazolin (Ancef) is given. If allergic to penicillin, clindamycin 600 mg IV is given as antibiotic prophylaxis.

 Next, the skin is prepared in a sterile fashion with 4% chlorohexidine diluted with sterile 0.9% normal saline with sterile gauze to clean all areas that will be treated with liposuction or fat grafting. Then, a 20 gauge spinal needle connected to a Wells Johnson® infiltration pump is used to superficially inject the tumescent anesthesia solution. Next, a #11 blade is used to make punctures in all planned liposuction sites. Lastly, a blunt infiltration cannula attached to the infiltration pump is used to infiltrate with majority of the tumescent solution into the deep and superficial fat layers until the tissues have a tense feel to them due to the increase hydrostatic pressure. The tissues area left undisturbed for ~20 min to allow for vasoconstriction by the epinephrine within the tumescent anesthesia infiltrated. During this time, the patient is prepared and draped in a sterile fashion for a second time but this time using a ChloraPrep™ stick. In addition, a lap sponge soaked in betadine solution is placed and secured over the anus with one 3-0 prolene suture at the level of the sacrum and a 3 M ioband dressing to completely seal off the anus from potentially contaminating the sterile field (**Figure 18**). The maximum concentration of lidocaine used is 35 mg/kg and all cases are done under general endotracheal anesthesia.

Next, 3 or 4 mm liposuction cannulas are used to harvest the fat from all areas to be treated. The fat is collected sterile into a 3 L, glass, and reusable sterile canister. Excess fluid and blood settles on the bottom of the canister and fat micro-grafts float to the top of the canister via continuous vibration table. The excess fluid is decanted to isolate only the fat grafts. The fat is then treated with an antibiotic solution

#### **Figure 18.**

*A lap sponge soaked in betadine solution is placed and secured over the anus with one 3-0 Prolene suture at the level of the sacrum and covered with a 3M ioband dressing to completely seal off the anus from the sterile field. Drains are commonly used and punctures sealed sterilely in an effort to prevent post op infections.* 

#### **Figure 19.**

*The fat infiltration technique used by the authors is a superficial grafting technique above the muscle in a parallel plane to the back which keeps the cannula well above the superior and inferior gluteal veins. Injection should be keep out of the inner bowl of the pelvis and essentially stay above the boney crest.* 

 containing 80 mg gentamicin and 600 mg of clindamycin mixed in a saline solution of 250 ml. Right before the fat is about to be injected back into the patient, 5–6 cc of platelet rich plasma (PRP) from the patient's own blood is mixed with the fat. A 4 mm infiltration cannula with a single hole is used to pump the fat back into the patient's buttocks. The fat infiltration technique most often used by the authors is a superficial grafting technique above the muscle in a parallel plane to the back and far from the superior and inferior gluteal veins to avoid injury which could lead to fat emboli (**Figure 19**). A pressure-controlled injection system by Wells Johnson is used which cuts off automatically if it senses pressures higher than central venous pressure. The preferred infiltration system is a closed loop injection system that includes a vibrating table to help with separation of the fat from the supernatant. The advantages of this system when compared to previous methods of fat grafting include efficiency, perfect micro-droplet size, more sterile or cleaner, and low pressure of injection.
