Cryolipolysis, popularly known as CoolSculpting, is a trademark owned by Zeltiq Aesthetics, Inc.. According to the trademark registration file, it refers to a medical device used to destroy fat cells. Its principle relies on controlled cooling for non-invasive local reduction of fat deposits to reshape body contours.The exposure to cooling is set so that it causes cell death of subcutaneous fat tissue without apparent damage to the overlying skin. The procedure is billed as a nonsurgical alternative to liposuction. The name Cryolipolysis is an acronym of Cryogenic Lipolysis. Cryogenic lipolysis is the process of controlled cooling to reduce localised fat deposits used in Cool Sculpting, 3D Lipo and Cryolipo.
In Europe the Cryolipolysis machines are used also in aesthetic clinics and spas. For example 3D-Lipo  and Cryolipo, a registered trademark owned by Cryotech Nordic  Ltd are rapidly expanding in Europe. Cryotech Nordic operates under the product brand CTN, and is the main provider of this technology in Europe, Middle-East and Asia. Cryotech Finland Oy is their research & development unit and runs a chain of Cryoclinics in the region.
Method of action and animal studies
Lipolysis procedures attempt to "dissolve" fat cells by nonsurgical means. A number of methods have been attempted, including the use of laser, ultrasound, and rf current. Popsicle panniculitis is a dermatologic condition that shows that exposure to low temperatures can selectively damage subcutaneous fat while leaving skin intact. Based on this premise, fat cells are more easily damaged by cooling than skin cells, cryolipolysis was developed applying low temperatures to tissue via thermal conduction. In order to avoid frostbite, a specific temperature level and exposure is determined. Physicians Dieter Manstein, MD, PhD and R. Rox Anderson, MD at The Wellman Center at Massachusetts General Hospital originated the concept, explored it in a number of experiments on pigs, and reported their data in 2008.  While the process is not fully understood, it appears that fatty tissue that is cooled below body temperature but above freezing undergoes localized cell death followed by a local inflammatory response, a local panniculitis, that gradually over the course of several months results in a reduction of the fatty tissue layer. When exposed to extreme cold, the body's usual response is to restrict circulation to keep the core of the body at the correct temperature. Cryolipolysis makes use of a powerful vacuum which adds to the inflammatory response by drawing blood up to the surface layers of the skin.
Experience in humans
The first human study appeared in 2009 when Coleman et al. reported results after cryolipolysis had been applied to love handles in a single session to ten patients, each patient being their own control. A session takes less than an hour and does not require anesthesia. With a single treatment subjects had a 20% reduction after two months and 25% reduction at six months in the fat layer as assessed by ultrasound. The lipolytic effect of treatment takes place within about two to four months. It appears primarily applicable for limited discrete fat bulges. With the small number of patients treated clinical data remain scarce, thus it is not known how long the treatment effect will last, or when and if later treatments would be necessary to maintain the result.
Side effect data are based on a limited experience. Transient local redness, bruising and numbness of the skin are common side effects of the treatment and expected to subside. Typically sensory deficits will subside within a month. The effect on peripheral nerves was investigated and failed to show permanent detrimental results. No serious long-lasting side effects were encountered during follow-up time of 6 months. Scarring, ulcerations, or changes in blood lipids or liver functions have not been reported.
In September 2010, the Food and Drug Administration approved two non surgical devices for the purpose of selective fat reduction, one being the Zerona laser, the other the Zeltiq device for “cryolipolysis”. Zeltiq Aesthetics of Pleasanton, California, which developed the cryolipolysis device was founded by Scott Wolf, MD, with funding from venture capital companies including Advanced Technology Ventures, Frazier Healthcare Ventures, Venrock and Aisling Capital. It had already been approved to cool skin for pain reduction in selected applications and was used "off label" prior to FDA approval for cryolipolysis. The term "cryolipolysis" is trademark-protected.
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