title: The efficacy of external ultrasound-assisted liposuction: a randomized controlled trial.
abstract: BACKGROUND
  Use of high-intensity, high-frequency external ultrasound before liposuction has been reported to enhance the ease of fat extraction, increase the amount of fat extracted, and decrease patient discomfort during liposuction.
  
  
  OBJECTIVE
  The purpose of this study was to compare the effect of application of high-intensity continuous wave ultrasound to extremely low-intensity ultrasound (placebo) prior to tumescent liposuction.
  
  
  METHODS
  A total of 19 patients (25 sites) completed the double-blind study. We used a split treatment area design so that each patient could serve as their own control. After tumesing the treatment area, a 3 W/cm2 continuous wave 1 MHz ultrasound was applied for 10 minutes. The placebo control was treated with 0.3 W/cm2 1 MHz for 10 minutes. Traditional tumescent liposuction followed ultrasound application. Doctors completed a visual analog scale rating the following: rate of extraction, degree of resistance to cannula movement, and color of fat. Patients also completed a questionnaire after the procedure and at 1 month postoperatively. Histologic samples of the fat treated with external ultrasound were taken from two patients.
  
  
  RESULTS
  In 14 of 19 patients the doctors graded either no difference between treatment and control sides or found a better response on the nontreated side in rate of fat removal and resistance to cannula advancement giving a P value of .0096. Only 5 of 19 aspirates were graded as differing in redness between treatment and control sides. Four of these were more red on the control side and one was more red on the treatment side. Therefore 15 of 19 had no better result with treatment, giving a P value of .0022. Seven patients graded the sensation during suctioning and/or postoperative course as better on the control side, four graded these variables as better on the treatment side, four showed no difference between the two sides, and four had mixed results. This gives only 4 of the 19 patients showing any advantage in treatment with a P value of .0022.
  
  
  CONCLUSIONS
  When the placebo effect is eliminated, there is no advantage to the application of external ultrasound prior to liposuction.
authors.affiliation: Division of Dermatologic Surgery, Cooper Hospital University Health System, Marlton, New Jersey, USA.
authors.forename: N
authors.initials: N
authors.lastname: Lawrence
authors.forename: S E
authors.initials: SE
authors.lastname: Cox
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology; D000328:Adult; D004311:Double-Blind Method; D006801:Humans; D015187:Lipectomy / Q000379:methods; D017060:Patient Satisfaction; D011795:Surveys and Questionnaires; D018084:Ultrasonography, Interventional