Interest in noninvasive body contouring is growing due to the fact that it is effective, affordable, has a short downtime, and is easy to perform. In the United states, in almost three quarters of a million such treatments were delivered during 2018.1 The main caveat is that multiple treatments are often required. The requirement for timing and number of treatments differs according to the specific treatment modality and the desired effects. It is important to ensure patients understand the limitations of these treatments and that they may well need repeating.
Noninvasive treatments for fat reduction have been shown to be effective and are associated with high rates of patient satisfaction. There are three (not two) main types of noninvasive treatment for fat reduction: cryolipolysis, high-intensity focused ultrasound (HIFU), and low-level laser therapy (LLLT). Each has a different mechanism of action and their own individual nuances. Only high-intensity ultrasound works by heating the fat cells to cause damage to them. Noninvasive treatments may be a reasonable alternative to surgical interventions such as liposuction, but they do not represent alternatives to weight loss, which should be encouraged in overweight patients.1,2
Cryolipolysis is a treatment used to reduce fat cells in localized areas of adipose tissue such as the flanks, thighs, abdomen, and neck. The technique involves first marking the areas for treatment and then applying conduction gel to these areas. A cooling applicator is then attached to the skin with a mild vacuum device that has either one or two panels. Tissue is drawn into the cooling panel and treatment is delivered for 30 to 60 minutes. Patients need to understand the process in advance of the treatment and the symptoms they will experience. Erythema posttreatment with cryolipolysis is a very consistent finding and patients must be aware of this. It resolves spontaneously over 7 days. Many patients are likely to also experience minor discomfort during treatment and then go on to experience 2 to 3 days of edema to the treated areas. The pain they experience is usually well controlled with simple topical and oral analgesics. In addition, patients often experience decreased light touch sensitivity and temperature sensitivity to the treated areas after treatment. This completely resolves spontaneously within 8 weeks of treatment. Patients should also understand the potential for undercorrection or overcorrection of fat areas, possible contour irregularities, and undesirable overlying skin changes. As with many interventions, there is no guarantee of a specific aesthetic outcome.1ā3
Cryolipolysis is a noninvasive treatment used to reduce fat volumes in specific body areas such as the arms, bra line, back, abdomen, flank, banana roll, and thighs. There is a large volume of evidence to support its use. For example, a systematic review of cryolipolysis treatment in 2015 showed average reductions in caliper measurement of subcutaneous tissues as high as 28.5% (range: 14.7ā28.5%).1 This evidence supports the clinical effectiveness of this treatment. Another study reviewed results in 53 patients in whom a single cryolipolysis treatment was delivered to the saddlebags. At 6 months posttreatment, mean thigh circumference had decreased 5.6 cm and the mean decrease in fat layer thickness measured by ultrasound was 1.3 cm. Patient satisfaction was also high (94% satisfaction rate).2 The precise mechanism of action by which cryolipolysis works is not well understood; however, it is theorized to be related to apoptosis-mediated cell death and subsequent inflammatory response or through cold-induced thermogenesis.3,4 Preclinical animal studies showed a 33% reduction in thickness of the superficial fat layer with maximal relative loss of nearly 80% with a single treatment.3 Although it is generally accepted that multiple treatments are required with noninvasive body contouring techniques, these data show that with cryolipolysis, single-treatment delivery can achieve beneficial effects.
HIFU is a noninvasive treatment used to reduce fat in specific body areas. It uses focused energy to thermally ablate subcutaneous adipose tissue and to induce neocollagenesis. HIFU increases the local temperature within the mid-lamellar fat layer leading to coagulative necrosis of adipocytes and subsequent reduction of fat layer.1 Apoptosis is programmed cell death and is believed to be one potential mechanism of action for cryolipolysis, a treatment that cools the subcutaneous tissues. The other proposed mechanism for cryolipolysis is cold-induced thermogenesis. Low-level laser energy (LLLT) is a nonthermal approach to fat reduction and the proposed mechanism of action is the induction of a transitory pore into an adipocyte resulting in release of lipids and adipocyte deflation.
HIFU is a noninvasive treatment used to reduce fat in specific body areas. It is indicated for waist circumference reduction and the ideal candidate is someone with a body mass index less than 30 and more than 2.5 cm of tissue on caliper pinch. There is a reasonable body of evidence to support its use. Two case series have been reported of 282 and 85 patients treated with HIFU to the abdomen and flank resulting in an average waist circumference decrease of 4.4 and 4.7 cm, respectively.1,2 A multicenter, randomized, sham-controlled, single-blinded trial of 180 patients studying HIFU in trunk aesthetics showed a decrease of 2.5 cm in the treatment group (single treatment) 1142 Part VII ā Aesthetic Surgery compared with 1.2 cm in the sham group.3 A multicenter, randomized, nonblinded study of 118 patients treated with a single HIFU treatment to the abdomen resulted in a decrease of 2.3 cm in waist circumference.4 The results are typically seen between 8 and 12 weeks posttreatment, so it is important to convey this information to patients prior to treatment to help set realistic expectations. The actual treatment involves marking the areas with the patient standing, followed by treatment delivery with the patient supine. Topical anesthetic is applied to the treatment areas. Multiple passes are made with the HIFU transducer to deliver the appropriate amount of energy, with the treatment usually being completed in less than an hour.
LLLT is a noninvasive, nonthermal approach to fat reduction performed with a laser wavelength of 635 nm. The proposed mechanism is mechanical disruption of the adipocyte leading to adipocyte deflation. Treatment involves transdermal delivery of the 635-nm laser which can cause a warming sensation during the procedure. Posttreatment erythema does occur but resolves within 24 hours. No dressings are required following this treatment. Multiple treatments will be required, but these are more frequent than monthly. Studies have reported outcomes after six treatments over 2 weeks or six consecutive weekly treatments. with good results.1ā3 LLLT is not a particularly painful procedure, so opiate medications are not required. More simple oral and topical analgesia should suffice. Moreover, opiate analgesics should be avoided where possible due to their addictive nature.
LLLT is indicated for circumference reduction of the upper arms, waist, hips, and thighs secondary to localized fat deposits. It involves the application of a laser device at 635 nm to target the subcutaneous tissues. The patient is marked standing then placed supine on the treatment table, exposing the area or areas to be treated. Laser diode modules are suspended ~15 cm above the anterior and then the posterior aspect of the treatment area and transdermal delivery of the 635 nm laser can commence. Specific distances, wattage, wavelength, and delivery duration vary depending on the device used. Complications are rare when the laser diode panel is appropriately placed; however, when it is applied directly to the skin, persistent erythema and skin ulceration may occur.1 This technical error is most likely to have occurred in this case and should be managed according to the principles of good wound care combined with an open and honest discussion with the patient. Patient selection is unlikely to be a cause of this problem unless they have a specific skin disorder. Contraindications otherwise are pregnancy, cancer, and large volume weight loss in obese patients. Too lengthy a treatment is also unlikely to cause this if the diode is correctly placed. No dressings are normally required after treatment, although they may be applied for patient comfort if desired.
abdomen? Paradoxical adipose hyperplasia (PAH) is a condition where instead of reducing fat by performing noninvasive fat reduction, a process of hyperplasia ensures, leading to an increase in tissue firmness and fullness. PAH is specifically associated with cryolipolysis and has an incidence of just less than 1%.1,2 When it does occur, it is unlikely to resolve spontaneously, and patients require an additional procedure to correct this. The primary treatment modality would be liposuction, although excisional surgery such as an abdominoplasty may also be considered. The main challenges of managing patients with PAH therefore are not only that they are in a worse position than when they started and will need some further surgical intervention, but they must also wait a number of months for the tissues to soften before any revision treatment can be undertaken. This would normally be at 6 to 9 months. The risk factors for developing PAH include male gender, Hispanic ethnicity, use of a large hand piece, and genetic predisposition.1ā3
There are a number of contraindications to using noninvasive body contouring techniques. Pregnancy is a contraindication across the board for all treatments. Cold urticarial is a contraindication specific to cryolipolysis. Mild skin laxity is not a contraindication to treatment, as a mild skin tightening effect can often be seen as a secondary benefit of these procedures. However, greater amounts of skin laxity are a contraindication to noninvasive treatments because the skin will not retract well following the procedure, leading to a compromised aesthetic result. Age is not a contraindication to any of the treatment modalities for noninvasive fat reduction. Liposuction is a useful surgical intervention for managing specific fat deposits, but it should not always be the first-line choice for every patient. Even if a patient is healthy enough and agreeable to undergo liposuction, if they may benefit from a noninvasive approach this should be considered first.1ā3