is cryolipolysis treatment safe ?
Clinical efficacy and safety of cryolipolysis
The clinical efficacy and safety of cryolipolysis has been studied in both human and animal models. In two separate studies, animal models demonstrated a reduction of up to 1 cm or 40% of the total fat layer thickness after a single exposure without harming the overlying skin. Manstein et al found lipid-laden mononuclear inflammatory cells and local thickening of fibrous septae at 2 weeks post-procedure, implicating apoptosis and phagocytosis as contributing factors in the mode of action. Evaluation of lipids over a 3-month period following treatment showed normal cholesterol and triglyceride levels.
Several studies in humans have shown comparable results. One study published in 2009 involving ten subjects reported a 20.4% and 25.5% reduction in the fat layer 2 months and 6 months after treatment, respectively.More recently, a retrospective multicenter study using patient surveys, photographic documentation, and caliper measurements, was published by Dierickx et al.These investigators reported that 86% of 518 subjects showed improvement. The body sites at which cryolipolysis was most effective were the abdomen, back, and flank. Patients completed a satisfaction questionnaire, with 73% reporting being satisfied and 82% being prepared to recommend cryolipolysis to a friend. The majority described minimal to tolerable discomfort during the procedure. Eighty-nine percent of respondents reported a positive perception of the treatment duration. In a report on the clinical and commercial experience with cryolipolysis in a private plastic surgery practice, only six of 528 patients were dissatisfied with the clinical outcome; four of these six patients were satisfied when treated a second time.A study by Garibyan et al used a three-dimensional camera to evaluate the amount of fat loss after cryolipolysis. Mean fat loss between baseline and the 2-month follow-up visit was 56.2±25.6 cc on the treated side and 16.6±17.6 cc on the control side (P<0.0001). Two months post-treatment, the mean difference in fat loss between the treated and untreated sides was 39.6 cc.In an uncontrolled study by Ferraro et al, cryolipolysis was combined with acoustic waves to achieve possible synergistic effects. These authors reported significant reductions of up to 6.7 cm in circumference and up to 4.5 cm in thickness of the fat layer 12 weeks after 3–4 treatments.However, it should be pointed out that body contouring studies are difficult to perform because natural variability is high and the reproducibility of many measurements is low.
The long-term duration of effect of cryolipolysis has not been evaluated as yet. Only one small case study of two subjects who were treated unilaterally on one flank and followed photographically for up to 5 years post-procedure has been published. In this study, fat reduction was found to be durable despite fluctuations in body weight.Although little to nothing is known about the durability of fat loss induced by selective cryolysis, there is no evidence that the fat lost after cold exposure could regenerate.
With regard to the safety profile, several publications including two systematic literature reviews have failed to identify any significant adverse events that could be attributed to cryolipolysis, including scarring, ulceration, or disfigurement. Although cold temperatures are known to induce subcutaneous panniculitis, no cases of nodule formation have been reported.xpected side effects are temporary erythema, bruising, and transient numbness that usually resolve within 14 days after treatment.With more than 850,000 procedures performed worldwide, only 850 adverse events have been reported. The most common complaint is late-onset pain, occurring 2 weeks post-procedure, that resolves without intervention. Paradoxical adipocyte hyperplasia, a condition where additional fat grows at the treatment site and occurs approximately 6 months postoperatively, has been reported in 33 cases.The pathogenesis of this phenomenon is unknown, but several hypothesized mechanisms are under discussion. Possible treatments rely on liposuction or abdominoplasty, because spontaneous resolution has not been reported as yet. Sensory alteration was investigated by Coleman et al in nine subjects by clinical neurological examination and biopsy for nerve staining.Six of the nine patients had a transient reduction in sensation, which returned to normal after a mean of 3.6 weeks. There were no neural changes on the biopsies. Potential changes in lipid levels after treatment were assessed in the two studies without any significant findings.Further, no notable changes in liver function were found in 40 patients followed for 12 weeks after cryolipolysis.