INTRODUCTION

Ultrasound therapy (US) is a biophysical modality used as an adjunctive treatment for chronic wounds such as pressure ulcers/injuries (PU/PI) and venous leg ulcers (VLU). It may be delivered using different frequencies and contact methods, including low-frequency noncontact systems and high-frequency contact systems.

CLINICAL

Types and Mechanisms

• Noncontact Low-Frequency Ultrasound (NCLF-US)
• Example: UltraMIST® Ultrasound Healing Therapy
• Mechanism: Delivers low-frequency (~40 kHz) ultrasonic energy through a saline mist to promote debridement and cleansing of the wound bed.
• Claimed to aid angiogenesis and growth factor stimulation.
• Contact High-Frequency Ultrasound (HFUS)
• Frequency: In the MHz range.
• Mechanism: Provides thermal effects stimulating macrophage and fibroblast activity, collagen synthesis, and growth factor secretion.

CODING, COVERAGE AND REIMBURSEMENT

Noncontact Low-Frequency Ultrasound (NCLF-US)

Low frequency, non-contact, non-thermal ultrasound (CPT code 97610) describes a system employed in wound care that uses continuous low frequency ultrasonic energy to atomize a liquid and deliver continuous low frequency ultrasound to the wound bed. [1][2][3] 

Noncontact Low-Frequency Ultrasound (e.g. MIST therapy)  is supported by evidence-based guidelines and systematic reviews when indicated; evidence suggests that it may be more comfortable for the patient than surgical debridement. [4] 

CTP codes

• CPT ® Codes 97610: Low frequency non-thermal ultrasound, including topical application(s), when performed, wound assessment, and instruction(s) for ongoing care, per day

HCPCS Level II Codes

Each device  is assigned a different HCPCS Level II code. To find each device's HCPCS: on WoundReference, go to the Product Navigator, open the device of interest, find the “Essentials” table, click on “HCPCS II” tab.

Medicare Coverage and Utilization

Medicare coverage eligibility

MAC coverage policies are subject to change. To ensure compliance, always confirm requirements with your specific MAC or review their LCD and Article. See topic "Medicare Coverage Determinations for Wound Care". For coverage eligibility requirements compiled from existing LCDs and articles, please refer to section ‘Coverage limitations and utilization guidance’ below.

Coverage limitations and utilization guidance

Listed below are coverage limitations and utilization guidance compiled from existing LCDs and local coverage articles on Low frequency, non-contact, non-thermal ultrasound.[1][2][3][4] 

Limitations

• MIST therapy or other similar products are included in the payment for the treatment of the same wound with other active wound care management CPT codes (97597, 97598, 97602, 97607, 97608) or wound debridement CPT codes (e.g., CPT codes 11042-11047, 97597, 97598).
• MIST Therapy or other similar treatments are separately billable only if other active wound management and/or wound debridement is NOT performed.

Billing and Coding Guidance

Below are billing and coding guidance provided by Medicare [4]: 

• Low-Frequency, Non-Contact, Non-Thermal Ultrasound is considered reasonable and necessary wound therapy and therefore eligible for coverage by Medicare when provided for any of the following clinical conditions:
• Wounds and ulcers which are too painful for sharp or excisional debridement and have failed conventional debridement with documentation supporting the same.
• Wounds and ulcers meeting Medicare coverage for debridement but with documented contraindications to sharp or excisional debridement.
• Wounds and ulcers meeting Medicare coverage for debridement where the normal process of healing has not progressed as expected at 30 days.

Utilization parameters

Below are billing and coding guidance provided by Medicare [4]:

• Noncontact Low-Frequency Ultrasound may be provided up to 2-3 times per week to be considered reasonable and necessary. No more than 18 services of low frequency, non-contact, non-thermal ultrasound within a six week period will be considered reasonable and necessary.
• The length of individual treatments will vary per wound size.
• Observable, documented improvements in the wound(s) should be evident after six treatments. Improvements include documented reduction in pain, necrotic tissue, or wound size, or improved granulation tissue.
• Documentation for low frequency, non-contact, non-thermal ultrasound (MIST Therapy) services should include documented improvements of pain reduction, reduction in wound size, improved and increased granulation tissue, or reduction in necrotic tissue. The services should be medically necessary based on the provider’s documentation of a medical evaluation of the patient's condition, diagnosis, and plan.