title: Noninvasive lifting of arm, thigh, and knee skin with transcutaneous intense focused ultrasound.
abstract: BACKGROUND
  Transcutaneous intense focused ultrasound is a novel Food and Drug Administration-approved technology for noninvasive skin tightening of the face and neck. No studies have reported on its safety and effectiveness on nonfacial areas.
  
  
  METHODS
  Eighteen paired areas (6 each) on the upper arms, medial thighs, and extensor knees were randomly treated with two different transducers (4.0 MHz, 4.5-mm focal depth and 7.0 MHz, 3.0-mm focal depth). One side was randomly assigned to receive a single pass (single plane) of microthermal coagulation zones over the involved area with the 4.0 MHz, 4.5-mm-depth transducer, and the contralateral side was assigned to receive consecutive single passes (dual plane) using both transducers (4.0 MHz, 4.5-mm depth followed by 7.0 MHz, 3.0-mm depth). Two independent masked assessors determined clinical improvement scores using comparative standardized photographs obtained at baseline and 3 and 6 months after treatment. Subjective assessments of clinical improvement and side effects of treatment were obtained.
  
  
  RESULTS
  Global assessment scores revealed significant improvement in all treated areas, with the upper arms and knees demonstrating more skin lifting and tightening than the thighs. Areas receiving dual-plane treatment had slightly better clinical scores than those receiving single-plane treatment in all three sites. Clinical scores from single-plane and dual-plane treated areas continued to improve between 3 and 6 months after treatment. Side effects were mild and transient and included erythema, warmth, and skin tenderness. Rare focal bruising was noted in two patients on the upper arms that resolved within 7 days. No other side effects were reported or observed.
  
  
  CONCLUSIONS
  Transcutaneous intense focused ultrasound can be safely and effectively used to improve the clinical appearance (texture and contour) of the upper arms, extensor knees, and medial thighs.
authors.affiliation: Washington Institute of Dermatologic Laser Surgery, Washington, District of Columbia 20005, USA. talster@skinlaser.com
authors.forename: Tina S
authors.initials: TS
authors.lastname: Alster
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Tanzi
mesh_terms: D000328:Adult; D000368:Aged; D000698:Analgesia / Q000379:methods; D001132:Arm; D003357:Cosmetic Techniques / Q000295:instrumentation*; D005260:Female; D006801:Humans; D007717:Knee; D008875:Middle Aged; D015595:Skin Aging; D013848:Thigh; D014464:Ultrasonic Therapy / Q000379:methods*