DALLAS – While cryolipolysis and high-intensity focused ultrasound are both effective at reducing subcutaneous fat in the flank region, cryolipolysis appeared to be less painful and more effective in a small, randomized trial.
Noninvasive subcutaneous fat reduction is becoming increasingly popular, study author Farhaad R. Riyaz, MD, observed at the annual conference of the American Society for Laser Medicine and Surgery. “High-intensity focused ultrasound seems to be less popular than cryolipolysis. It uses sound waves to create heat and is similar in technology to light traveling through a magnifying glass to create heat at a focal point. But the two technologies really haven’t been rigorously compared in the literature,” he added.
Dr. Riyaz and his associates in the division of cutaneous and aesthetic surgery at Northwestern University, Chicago, enrolled 12 healthy female participants with a body mass index between 18 and 30 kg/m2 and moderate fat in the abdomen flanks. In the split-body, parallel-group trial, the subjects were randomized to cryolipolysis on one flank and to high-intensity focused ultrasound (HIFU) on the contralateral side. Study participants were asked to maintain their weight throughout the 12-week study. Treatments were performed at baseline, week 4, and week 8, with a follow-up visit at week 12. The primary outcome was thickness of subcutaneous fat as measured by ultrasound; secondary outcomes included pain, patient-reported improvement, and total circumference of the abdomen and flanks.
The mean age of the 12 participants was 39 years, 8 were white, and most had Fitzpatrick skin types II and IV (33% and 42%, respectively). Dr. Riyaz reported that (P = .0007 and P = .0341, respectively), as measured by diagnostic ultrasound. The researchers noted significantly less fat in the flanks on the sides treated with cryolipolysis, compared with the sides treated with HIFU (P = .007). Study participants reported significantly more pain with HIFU compared with cryolipolysis (P = .0002).
“Although participant-reported improvement in the appearance of their flanks was significant for both treatments [P less than .0001], patients couldn’t appreciate a difference between the side that was treated with HIFU and the side that was treated with cryolipolysis,” Dr. Riyaz said. “In addition, the total abdominal circumference did not change throughout the study for either group.”
He reported having no financial disclosures.