An Analysis of Tissue Temperature and Adipocyte Morphology Following External Ultrasound with the MC1 Device

Purpose

      The VASER Shape MC1 is a non-invasive ultrasound (US) and massage system. It received FDA clearance in 2010 for relief of pain, muscle spasms and joint contractures.  The device has been used “off- label” for non-invasive body contouring on the premise that US diathermy may have a reducing effect on adipose tissues.  The purpose of this pre-clinical study is to determine both the time/temperature relationships and document cellular changes following MC1 treatments.

Methods

     The study was conducted under IACUC protocols. Mirror image areas (treatment and control) were marked on the abdomen of 3 anesthetized 70 kg pigs.  Evans Blue was injected to facilitate identification of the lymph system. Thermocouples were placed into the treatment area at different depths 2mm, 14mm and 30mm (confirmed by Touchview US) and a single thermocouple was inserted into the control area (Fig. 1). MC1 treatments were applied at manufacturer's recommended energy settings for 2 consecutive 30 min. intervals. A thermal camera recorded skin surface temperature. Lymphatic massage was performed towards adjacent lymph drainage area. Lymph samples were taken pre-treatment from control side and post treatment from treated side.  Biopsies were taken of the skin, adipose tissues and lymph nodes on both sides. Tissue temperatures were recorded throughout the treatment phase.

Results

     Analysis of the skin biopsies did not reveal any evidence of thermal damage. Electron microscopy studies of the treated adipose tissue revealed alterations in the cellular architecture (without necrosis) as compared to the control side. Lymph analysis revealed a significant increase in the lipid profile of the treated side. In particular, triglycerides were 1598 treated side versus 232 for control. Analysis of lymph node biopsies revealed free vacuoles of fat within the lymph tissue on treated side compared to normal lymph node histology on control side.  Temperature measurements for typical study subject are depicted in Fig. 2.

Conclusion

     The tissue temperatures produced by MC1 US treatments are not associated with thermal tissue damage at energy levels recommended for clinical use. Based on the cellular changes without necrosis as well as the increase in free lipids in the lymph system on the treated side, we conclude that treatment with this device may have a reducing effect on adipose tissue, possibly by altering the permeability of fat cells.