LAS VEGAS While cellulite can be easily identified, the basic science of its makeup remains a mystery.
"We still don't know what the definitive pathologic cause of cellulite is," Dr. Neil Sadick said at the annual meeting of the International Society for Dermatologic Surgery. "There are many aggravating factors such as weight loss that are thought to play a role, but none of them [has] been proven over the past 30 years. We believe that this is a sexual dimorphic secondary trait."
One theory he subscribes to is that cellulite "involves changes in the structure of the adipocyte and the surrounding septa, so that the septa are more vertically oriented, allowing movement of the adipocyte up to the dermis."
Dr. Sadick and his associates in the department of dermatology at Cornell University, New York, plan to launch a series of clinical trials with the New Jersey Medical School, Newark, in an effort to determine the content of fat found in cellulite.
They also plan to study receptors that have been shown to be involved and upregulated in people with cellulite, including peroxisome proliferator-activated receptors, uncoupling protein 1, and androgen receptors α-AR and β-AR. "By understanding more about the basic science of this condition, we hope to be able to introduce better therapies in the future," he said.
The current trend in cellulite therapy is marked by multimodal devices that "attempt to heat adipocytes, remodel adipocytes, and cause dermal remodeling in the septa surrounding the adipocyte cells," Dr. Sadick said. He discussed the following technologies:
▸ VelaShape (Syneron Medical Ltd.). This Food and Drug Administration-approved device combines bipolar radiofrequency power and infrared energy with vacuum and mechanical massage for circumferential reduction.
"There have been a number of publications in the scientific literature showing that there is some degree of efficacy in terms of remodeling the cellulite as well as circumferential fat reduction," he said.
In a study of 40 patients conducted at Dr. Sadick's clinic, 85% had a circumferential reduction of 1 cm or more after 12 treatments and 43% had a circumferential reduction of 2 cm or more.
"Up to 7.2-cm reduction in circumference was achieved" in some cases, he said.
▸ TriActive (Cynosure). This FDA-approved device combines a low-energy diode laser with suction massage that has been shown to achieve a global cellulite improvement in 75% of patients (Am. J. Cosmet. Surg. 2005;224:2335). "This is a very nice technology that can be used in this setting," Dr. Sadick commented.
▸ Accent (Alma). This FDA-approved device uses dual radiofrequency technology for circumferential reduction.
The unipolar setting targets deep dermal and subdermal layers and is used to treat large volumes of tissue, while the bipolar setting delivers energy superficially and is used to treat areas with a thinner dermis such as the face.
One recent study of 30 patients with cellulite grade III-IV who were treated 6 times over a 2-week period found that 27 achieved clinical improvement with a mean decrease in thigh circumference of 2.45 cm as measured by MRI (Dermatol. Surg. 2008;34:2049).
▸ SmoothShapes (Elemé Medical). This FDA-approved device combines a laser and an LED light source with mechanical rollers and a vacuum to "mold the adipocytes and to try and improve the metabolic parameters associated with cellulite," Dr. Sadick said.
One randomized trial of 74 patients treated twice a week for 4 weeks found that 81% had a significant volumetric reduction in subcutaneous fat (J. Lasers Surg. Med. 2004; suppl. 16:32). At 13 months post treatment, five patients underwent MRI and four of the five maintained their result.
In the future, he predicted, more "inside-outside" approaches to treating cellulite are likely to evolve, such as combining external technologies with internal laser lipolysis to "heat adipocytes and eat up septa. That probably will give the most effective results."
Dr. Sadick went on to note that while injectable treatment of cellulitis remains popular in the United States, "there is not a lot of good science behind it. We need to distinguish between true mesotherapy and injectable lipolysis. In true mesotherapy, we are attempting to eliminate some fat [and] have an effect on the metabolism of the adipocytes."
Agents being used for treating cellulite in mesotherapy include aminophylline, isoproterenol, ephedrine, calcium pyruvate, carnitine, and ma huang.
Another approach to cellulite treatment is detergent lipolysis, or mesotherapy, in which phosphatidylcholine and deoxycholate act as detergents, causing adipose cell walls to dissolve and break down.
"This is not FDA approved to date but there are FDA studies underway to determine the optimal solution," Dr. Sadick said.