|MP 2.01.79||Non-Contact Ultrasound Treatment for Wounds|
|Original Policy Date
|Last Review Status/Date
Reviewed with literature search/10:2011
|Return to Medical Policy Index|
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Low-frequency ultrasound in the kiloherz (KHz) range may improve wound healing. Several devices are available, including the MIST Therapy® system which delivers ultrasonic energy to wounds via a saline mist without direct skin contact.
Ultrasound (US) is defined as a mechanical vibration above the upper threshold of human hearing (> 20 KHz). Ultrasound (US) in the MHz range (1-3 MHz) has been used for the treatment of musculoskeletal disorders, primarily by physical therapists. Although the exact mechanism underlying its clinical effects is not known, therapeutic US has been shown to have a variety of effects at a cellular level including angiogenesis, leukocyte adhesion, growth factor and collagen production, and increases in macrophage responsiveness, fibrinolysis and nitric oxide levels. More recently, the therapeutic effects of US energy in the kilohertz range have been examined. It has been proposed that low frequency US in this range may improve wound healing via the production, vibration and movement of micron-sized bubbles in the coupling medium and tissue.
The mechanical energy from US is typically transmitted to tissue through a coupling gel. Several high-intensity US devices with contact probes are currently available for wound debridement. A non-contact low-intensity US device has been developed that does not require use of a coupling gel or other direct contact. The MIST Therapy™ System (Celleration) 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.
In 2005, the Celleration MIST therapy device 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.” Several wound drainage and wound vacuum systems were listed as predicate devices. In 2004, the U.S. Food and Drug Administration (FDA) had reclassified these devices from class III to class II at the request of Celleration (K032378).
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 removal of debris, exudates, fragments, and other matter.
Non-contact ultrasound treatment for wounds is considered investigational.
A category III CPT code specific to this non-contact ultrasound treatment is available for use:
0183T: Low frequency, non-contact, non-thermal ultrasound, including topical application(s) when performed, wound assessment, and instruction(s) for ongoing care, per day.
BlueCard/National Account IssuesState or federal mandates (e.g., FEP) may dictate that all FDA-approved devices may not be considered investigational and thus these devices may be assessed only on the basis of their medical necessity.
The objective of this review is to evaluate whether the addition of non-contact ultrasound (US) with saline mist improves wound healing in comparison with standard treatment alone. This policy was originally created in 2007 and was updated regularly with searches of the MEDLINE database. The most recent literature search was performed for the period August 2010 through August 2011. Following is a summary of the key literature to date:
Two industry-sponsored randomized controlled trials have assessed the incremental benefit of MIST therapy on wound healing. (1,2)
One double-blind multicenter randomized, controlled trial used MIST therapy for recalcitrant diabetic foot ulcers. (1) Most of the 133 patients (85%) were enrolled and treated at 17 different wound clinics/private practice centers. An additional 15% of patients were enrolled at 6 university medical clinics. Patients with recalcitrant foot ulcers were treated with active or sham saline mist therapy 3 times per week, with debridement as needed and a weekly evaluation by an independent investigator. Twenty-four patients were lost to follow-up, and data from 54 patients were excluded from analysis due to protocol violations (5 centers were found to have inverted the treatment distances for the active and sham devices), leaving 55 patients (41%) for the per-protocol analysis. The investigators reported significant improvement (11 of 27 patients [41%] versus 4 of 28 patients [14%]) in the proportion of wounds healed (defined as complete epithelialization without drainage). However, intent-to-treat analysis showed no difference in wound healing (26% vs. 22%) between the active (n =70) and control (n = 63) groups. In addition to the 59% loss to follow-up, there was a difference in the ulcer area at baseline (1.7 vs. 4.4 cm²) and chronicity of wounds (35 vs. 67 weeks) that favored MIST therapy in the per-protocol groups. Due to the serious limitations of this study, these results are considered inconclusive.
Kavros et al. randomized 70 patients with nonhealing (2 months) foot, ankle, or leg wounds to standard of care alone or standard of care plus MIST therapy for 12 weeks. (2) To participate, patients with documented ischemia (transcutaneous oximetry of 40 mm Hg or less) had to agree to 3 times per week visits for therapy. This open-label (non-blinded) study found that a greater proportion of patients in the MIST therapy group (22 of 35, or 63%) achieved wound healing (defined as a reduction of wound area greater than 50%) in comparison with standard of care alone (10 of 35 or 29% of patients). Non-specific effects of the additional treatment sessions were not controlled for. In addition, although the study reported on the importance of baseline transcutaneous partial pressure of oxygen (TcPO2) on wound healing, patients with low (1–20 mm Hg) and high (21–40 mm Hg) TcPO2 levels do not appear to be equally distributed between the groups. In a retrospective analysis by Kavros and colleagues, wound healing in 163 patients treated with MIST therapy (3 times per week for 90 days) was found to be 53%, compared with 32% from 47 matched controls treated during the same period who were unable to undergo 3 weekly visits. (3)
An industry-sponsored meta-analysis, published in 2011, identified 10 studies evaluating non-contact low-frequency US therapy for treating chronic wounds. (4) To be eligible for inclusion in the meta-analysis, studies had to have at least 4 weeks of follow-up. (4) Two studies were excluded, 1 because data were not in a form suitable for pooling and the other because follow-up time was too short. Of the remaining 8 studies, 1 was a RCT, and the remainder were observational studies (5 retrospective analyses and 2 prospective studies). A pooled analysis of findings from 7 studies (total n =429) found that a mean of 32.7% (95% confidence interval [CI]: 23.3% to 42.1%) of patients had healed wounds by a mean of 6 weeks. A pooled analysis of 4 studies (total n =188) found a mean of 85.2% (95% CI: 64.7% to 97.6%) reduction in wound area by final follow-up. The major limitation of this meta-analysis was that there were no pooled comparisons of non-contact US therapy to optimal wound care alone, or to an alternative intervention. Thus conclusions cannot be drawn about the incremental benefit of non-contact ultrasound treatment over optimal wound care alone.
Other studies include a systematic review, published in 2008, that identified the 2 randomized trials described above and no additional studies. (5) Non-contact US for treating wounds has also been evaluated in case series, such as a retrospective chart review involving 76 patients. (6) In addition, use of non-contact ultrasound for burns has been reported in a small uncontrolled case series. (7)
Currently available scientific evidence does not permit conclusions concerning the effect of this technology on health outcomes. There are two RCTs that report benefits on some outcomes, but both trials have substantial methodologic flaws that limit the validity of the findings. Well-designed, blinded studies that have adequate numbers of patients and that include all relevant outcomes are needed to further evaluate the efficacy of this treatment. Therefore, non-contact ultrasound treatment for wounds is considered investigational.
Practice Guidelines and Position Statements
In 2010, the Association for the Advancement of Wound Care (AAWC) published a guideline on care of pressure ulcers. (8) Non-contact ultrasound therapy was included as a potential second-line intervention if first-line treatments did not result in wound healing.
Medicare National Coverage
No national coverage determination.
- Ennis WJ, Foremann P, Mozen N et al. Ultrasound therapy for recalcitrant diabetic foot ulcers: results of a randomized, double-blind, controlled, multicenter study. Ostomy Wound Manage 2005; 51(8):24-39.
- Kavros SJ, Miller JL, Hanna SW. Treatment of ischemic wounds with noncontact, low-frequency ultrasound: the Mayo clinic experience, 2004-2006. Adv Skin Wound Care 2007; 20(4):221-6.
- Kavros SJ, Liedl DA, Boon AJ et al. Expedited wound healing with noncontact, low-frequency ultrasound therapy in chronic wounds: a retrospective analysis. Adv Skin Wound Care 2008; 21(9):416-23.
- Driver VR, Yao M, Miller CJ. Noncontact low-frequency ultrasound therapy in the treatment of chronic wounds: A meta-analysis. Wound Rep Reg 2011; 19(4):475-80.
- Ramundo J, Gray M. Is ultrasonic mist therapy effective for debriding chronic wounds? J Wound Ostomy Continence Nurs 2008; 35(6):579-83.
- Bell AL, Cavorsi J. Noncontact ultrasound therapy for adjunctive treatment of nonhealing wounds: retrospective analysis. Phys Ther 2008; 88(12):1517-24.
- Samies J, Gehling M. Acoustic pressure wound therapy for management of mixed partial- and full-thickness burns in a rural wound center. Ostomy Wound Manage 2008; 54(3):56-9.
- Association for the Advancement of Wound Care (AAWC). Association for the Advancement of Wound Care guideline of pressure ulcer guidelines. Malvern, PA. Available online at: www.guideline.gov. Last accessed September 2011.
|CPT||See Policy Guidelines|
|ICD-9 Diagnosis||Investigational for all codes|
|ICD-10-CM (effective 10/1/13)||Investigational for all diagnoses|
|E08.621, E08.622, E09.621, E09.622, E10.621, E10.622, E11.621, E11.622, E13.621, E13.622||Various types of diabetes with skin complications (foot ulcer or other skin ulcer) code list|
|I83.001-I83.029; I83.201-I83.229||Varicose veins with ulcer code range|
|L00 – L08.9||Infections of the skin code range (includes cellulitis – L03)|
|L89.00-L89.95||Pressure ulcer code range|
|L97.10-L97.929||Non-pressure chronic ulcer of skin code range|
|L98.41-L98.499||Non-pressure chronic ulcer of skin not otherwise classified code range|
|L99||Other disorders of skin and subcutaneous tissue in diseases classified elsewhere|
|ICD-10-PCS (effective 10/1/13)||ICD-10-PCS codes are only used for inpatient services. There is no specific ICD-10-PCS code for the initiation or application of this therapy.|
|12/13/07||Add policy to Medicine Section||New policy|
|10/07/08||Replace policy||Policy updated with literature review through August 2008; reference numbers 4 and 5 added; policy statement unchanged|
|10/06/09||Replace policy||Policy updated with literature review through August 2008; references renumbered and references 5 and 6 added; policy statement unchanged|
|10/08/10||Replace policy||Policy updated with literature review through August 2010; rationale re-written; references renumbered and reference number 5 added; policy statement unchanged|
|10/04/11||Replace policy||Policy updated with literature review through August 2011; references 4 and 8 added; other references renumbered or removed; policy statement unchanged|