title: Evaluation of clinical effectiveness of MIST ultrasound therapy for the healing of chronic wounds.
abstract: OBJECTIVE
  (1) To determine the incidence of wound closure for chronic nonhealing lower extremity wounds of various etiologies using MIST ultrasound therapy, a 510(K)-approved, low-frequency, noncontact ultrasound device indicated for the cleansing and debridement of chronic wounds. (2) To determine the optimum treatment duration for therapy with this low-frequency, noncontact ultrasound device, quantifying end points that correlate with a maximal clinical response and identifying potential synergistic therapies that could be used in conjunction with this therapy. (3) To analyze the impact of low-frequency noncontact ultrasound therapy on the microcirculatory flow patterns within the wound bed.
  
  
  METHODS
  A noncomparative clinical outcomes trial utilizing low-frequency, noncontact ultrasound.
  
  
  METHODS
  A tertiary-referral hospital-based wound clinic.
  
  
  METHODS
  Twenty-three patients from a single tertiary-referral hospital-based wound clinic. Control data were obtained from a previously published, prospectively collected database from the same clinic.
  
  
  METHODS
  During an 8-month period, a total of 29 lower extremity wounds in 23 patients who met criteria for inclusion were treated with low-frequency, noncontact ultrasound therapy. Standard of care was provided for 2 weeks for all wounds screened for the study. A failure to achieve an area reduction greater than 15% qualified the patient for enrollment to the trial and the addition of low-frequency, noncontact ultrasound therapy to the current treatment regimen.
  
  
  METHODS
  Wound healing, area and volume reduction, and laser Doppler-derived mean voltage (a marker for microcirculatory flow) are the main outcome measures for the study.
  
  
  RESULTS
  Overall, 69% of the wounds in the study were healed using an intent-to-treat model. When low-frequency, noncontact ultrasound was used as a stand-alone device, median time to healing was 7 weeks. Historic controls were healed with a median time to healing of 10 weeks; however, a statistically significant number of these patients required wound-related hospitalization and surgical procedures to achieve closure compared with the wounds in the present study.
  
  
  CONCLUSIONS
  Treatment with low-frequency, noncontact ultrasound achieved healing in chronic wounds when used as a stand-alone device or in combination with moist wound care in 69% of cases. Response to low-frequency, noncontact ultrasound was evident within 4 weeks of therapy. Earlier transition to secondary procedures and decreased utilization of inpatient care might result in more cost-effective wound healing than the current standard of care. A well-designed health economic-based trial is warranted to assess this technology.
authors.affiliation: Comprehensive Wound and Disease Management Center, St. James Olympia Fields Hospital, Olympia Fields, IL, USA.
authors.forename: William J
authors.initials: WJ
authors.lastname: Ennis
authors.forename: Wesley
authors.initials: W
authors.lastname: Valdes
authors.forename: Marianne
authors.initials: M
authors.lastname: Gainer
authors.forename: Patricio
authors.initials: P
authors.lastname: Meneses
mesh_terms: D000368:Aged; D001784:Blood Gas Analysis; D002908:Chronic Disease; D003362:Cost-Benefit Analysis; D003646:Debridement; D004867:Equipment Design; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D017078:Laser-Doppler Flowmetry; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D018919:Neovascularization, Physiologic; D011446:Prospective Studies; D017592:Skin Care / Q000379:methods; D013997:Time Factors; D016896:Treatment Outcome; D014464:Ultrasonic Therapy / Q000191:economics / Q000295:instrumentation / Q000379:methods*; D014945:Wound Healing; D014947:Wounds and Injuries / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*