Medical Policy: 01.01.25 

Original Effective Date: May 2014 

Reviewed: March 2021 

Revised: March 2020 



This policy contains information which is clinical in nature. The policy is not medical advice. The information in this policy is used by Wellmark to make determinations whether medical treatment is covered under the terms of a Wellmark member's health benefit plan. Physicians and other health care providers are responsible for medical advice and treatment. If you have specific health care needs, you should consult an appropriate health care professional. If you would like to request an accessible version of this document, please contact customer service at 800-524-9242.


Benefit Application:

Benefit determinations are based on the applicable contract language in effect at the time the services were rendered. Exclusions, limitations or exceptions may apply. Benefits may vary based on contract, and individual member benefits must be verified. Wellmark determines medical necessity only if the benefit exists and no contract exclusions are applicable. This medical policy may not apply to FEP. Benefits are determined by the Federal Employee Program.


This Medical Policy document describes the status of medical technology at the time the document was developed. Since that time, new technology may have emerged or new medical literature may have been published. This Medical Policy will be reviewed regularly and be updated as scientific and medical literature becomes available.



A non-contact low-frequency US device has been developed that does not require use of a coupling gel or other direct contact. In 2005, the MIST Therapy™ System (Celleration, Inc.) received marketing clearance (K050129) through the FDA's 510(k) process, “to promote wound healing through wound cleansing and maintenance debridement by the removal of yellow slough, fibrin, tissue exudates and bacteria.” The MIST Therapy™ System delivers a saline mist to the wound with low-frequency US (40 KHz); it includes a generator, a transducer, and a disposable applicator for discharge of prepackaged saline. Several wound drainage and wound vacuum systems were listed as predicate devices.


In 2007, the AR1000 Ultrasonic Wound Therapy System (Arobella Medical) received marketing clearance, listing the Celleration MIST system and several other ultrasonic wound debridement and hydrosurgery systems as predicate devices. The AR1000 system uses a combination of irrigation and US with a contact probe to debride and cleanse wounds. The indications are similar to that of the MIST system, listed as: “selective dissection and fragmentation of tissue, wound debridement (acute and chronic wounds, burns, diseased or necrotic tissue), and cleansing irrigation of the site for the removal of debris, exudates, fragments, and other matter.”


Other ultrasound therapy that may be used includes the Qoustic Wound Therapy System, the Sonoca 180/185 Wound Care System, VERSAJET II Hydrosurgery System, SonicOne O.R.. Jetox ND, AS1000 Ultrasound Wound Therapy System.


Low frequency ultrasound is used as an adjunct (supplement) to wound care. A noncontact low frequency ultrasound device is intended to provide debridement and cleansing to a wound. The device is held 0.5 to 1.5 cm from the wound and saline is delivered to the wound bed, which purportedly promotes healing through stimulation of cellular activity. Therapy is usually given in three-to-twelve minute sessions, three times per week.


Practice Guidelines and Position Statements

Association for the Advancement of Wound Care 

In 2014, the Association for the Advancement of Wound Care (AAWC) published guidelines on the care of pressure ulcers.16, Noncontact low-frequency ultrasound therapy was included as a potential second-line intervention if first-line treatments did not result in wound healing.


The AAWC guidelines on the treatment of venous ulcers, updated in 2015, stated that low-frequency ultrasound treatment requires additional evidence before it can be considered an appropriate treatment.


American Podiatric Medical Association

The American Podiatric Medical Association in collaboration with the Society for Vascular Surgery and the Society for Vascular Medicine developed a 2016 clinical practice guideline for the management of diabetic foot. Their recommendations do not include warming therapy, noncontact normothermic wound therapy or low frequency ultrasound for the treatment of wounds.


The Society for Vascular Surgery

The Society for Vascular Surgery in collaboration with the American Podiatric Medical Association published joint guidelines on the management of diabetic foot in 2016. The guidelines recommended adjuvant therapy for diabetic foot ulcers that fail to demonstrate more than 50% wound area reduction after 4 weeks of standard wound therapy. The adjunctive wound therapy options listed in the guidelines included negative pressure therapy, biologics (platelet-derived growth factor, living cellular therapy, extracellular matrix products, amniotic membrane products), and hyperbaric oxygen therapy. Ultrasound therapy was not mentioned as a recommended adjuvant option.


Regulatory Status

Examples of low-frequency ultrasound devices include, but may not be limited to:

  • AR1000 Ultrasonic Wound Therapy System
  • AS1000 Ultrasound Wound Therapy System
  • Jetox ND
  • MIST Therapy System
  • SonicOne OR
  • SONOCA-185
  • VERSAJET II Hydrosurgery System


Several other devices have been approved as being substantially equivalent to the earlier devices. FDA product code: NRB.


Prior Approval:

Not applicable.



Use of low-frequency, non-contact, non-thermal, ultrasound therapy is considered investigational for wound care and all other applications.


For individuals who have any wound type (acute or nonhealing) who receive noncontact ultrasound therapy plus standard wound care, the evidence includes RCTs and systematic reviews. Relevant outcomes are symptoms, change in disease status, morbid events, quality of life, and treatment-related morbidity. The single double-blinded, sham-controlled randomized trial, which included patients with nonhealing diabetic foot ulcers, had substantial methodologic flaws (eg, high dropout rate, baseline differences between groups) that limit the validity of the findings. In the remaining studies comprising the evidence base most studies compare non-contact ultrasound with standard wound care reported improved (statistically significant) results on the primary outcome with non-contact ultrasound. However, these studies also had several methodologic limitations. Complete healing is the most clinically relevant outcome. None of the RCTs evaluating venous leg ulcers reported complete healing as its primary outcome measure, and none had blinded outcome assessment. Another limitation of the body of evidence is that some standard of care interventions involved fewer visits than the non-contact ultrasound intervention, and the differences in intensity of care resulting from this differential in face-to-face contact could partially explain the difference in findings between intervention and control groups. In general, most of the studies did not have many participants, had short follow-up times and had poor study design. The evidence is insufficient to determine the effects of the technology on health outcomes.


Procedure Codes and Billing Guidelines:

To report provider services, use appropriate CPT* codes, Modifiers, Alpha Numeric (HCPCS level 2) codes, Revenue codes, and/or diagnosis codes.

  • 97610 Low frequency, non-contact, non-thermal ultrasound, including topical application(s) when performed, wound assessment, and instruction(s) for ongoing care; per day
  • A6000 Non-contact wound warming wound cover for use with the non-contact wound warming device and warming card


Selected References:

  • National Institute for Health and Clinical Excellence. Medical technology guidance 5. The MIST Therapy system for the promotion of wound healing July 2011.
  • U.S. Food and Drug Administration 510(k) Premarket Notification Database. Celleration MIST Therapy System Summary of Safety and Effectiveness No. K032378. Rockville, MD: FDA. June 25, 2004. No. K050129. May 2005.
  • Association for the Advancement of Wound Care (AAWC). Venous Ulcer Guideline
  • Association for the Advancement of Wound Care (AAWC). Pressure Ulcer Guideline
  • Velez-Diaz-Pallares M, Lozano-Montoya I, Abraha I, et al. Nonpharmacologic interventions to heal pressure ulcers in older patients: An overview of systematic reviews (The SENATOR-ONTOP Series). J Am Med Dir Assoc. 2015;16(6):448-469.
  • Game FL, Apelqvist J, Attinger C, et al. Effectiveness of interventions to enhance healing of chronic ulcers of the foot in diabetes: A systematic review. Diabetes Metab Res Rev. 2016;32 Suppl 1:154-168.
  • Qaseem A, Humphrey LL, Forciea MA, et al.; Clinical Guidelines Committee of the American College of Physicians. Treatment of pressure ulcers: A clinical practice guideline from the American College of Physicians. Ann Intern Med. 2015;162(5):370-379.
  • White J, Ivins N, Wilkes A, et al. Non-contact low-frequency ultrasound therapy compared with UK standard of care for venous leg ulcers: A single-centre, assessor-blinded, randomised controlled trial. Int Wound J. 2015 Jan 25 [Epub ahead of print].
  • Hingorani, Anil, LaMuraglia, Glenn, Henke, Peter, et al. The management of diabetic foot: A clinical practice guideline by the Society for Vascular Surgery in collaboration with the American Podiatric Medical Association and the Society for Vascular Medicine. Journal of Vascular Surgery. February 2016;63(25).
  • Cullum N, Liu Z. Cullum N, Liu Z. Therapeutic ultrasound for venous leg ulcers. Cochrane Database of Systematic Reviews 2017, Issue 5. Art. No.: CD001180. DOI: 10.1002/14651858.CD001180.pub4.
  • Chang YR, Perry J, Cross K. Low-frequency ultrasound debridement in chronic wound healing: a systematic review of current evidence. Plast Surg (Oakv). Feb 2017;25(1):21-26. PMID 29026808


Policy History:

  • March 2021 - Annual Review, Policy Renewed
  • March 2020 - Annual Review, Policy Revised
  • March 2019 - Annual Review, Policy Renewed
  • March 2018 - Annual Review, Policy Revised
  • March 2017 - Annual Review, Policy Revised
  • March 2016 - Annual Review, Policy Renewed
  • April 2015 - Annual Review, Policy Renewed
  • May 2014 - New Policy

Wellmark medical policies address the complex issue of technology assessment of new and emerging treatments, devices, drugs, etc.   They are developed to assist in administering plan benefits and constitute neither offers of coverage nor medical advice. Wellmark medical policies contain only a partial, general description of plan or program benefits and do not constitute a contract. Wellmark does not provide health care services and, therefore, cannot guarantee any results or outcomes. Participating providers are independent contractors in private practice and are neither employees nor agents of Wellmark or its affiliates. Treating providers are solely responsible for medical advice and treatment of members. Our medical policies may be updated and therefore are subject to change without notice.


*CPT® is a registered trademark of the American Medical Association.