Helium Plasma Subdermal Tissue Contraction Method of Action
Diane Irvine Duncan MD, FACS and Shawn Roman
Background and Purpose:
The principle of thermally-induced contraction of collagen through denaturation and coagulation of soft tissue is well known in medicine and is used to achieve beneficial results in ophthalmology, orthopedics, varicose vein ablation, and cosmetic plastic surgery procedures. Once tissue is heated to the appropriate temperature, protein denaturation and collagen contraction occur resulting in a reduction of volume and surface area of the heated tissue. Recently, a helium-based plasma technology has been introduced for the percutaneous delivery of plasma energy for the purpose of soft tissue coagulation and contraction. The purpose of this research was to understand the internal and external tissue temperatures resulting from treatment with the helium plasma device and the impact of device settings on temperature during the coagulation and contraction of subcutaneous soft tissue.
Simulated use of the helium plasma device was performed on the abdomen of a live domestic cross pig following Klein solution infiltration and liposuction. Incisions through the epidermis and into the subcutaneous tissue plane were used as visualization windows to allow a FLIR camera to capture internal and external tissue temperatures simultaneously during activation. Internal and external tissue temperatures were recorded for various power and helium gas flow settings.
For all but one treatment combination, the external tissue temperatures did not increase more than 3.6°C from baseline over the course of six treatment passes. Maximum internal tissue temperatures for 60% and 80% power settings exceeded 85°C for approximately 0.08 seconds while maximum temperatures for 40% power settings remained below 85°C.
Helium plasma power settings between 60% and 80% produce soft tissue coagulation and contraction by rapidly heating the treatment site to temperatures greater than 85°C for approximately 0.08 seconds. A power setting of 40% does not heat the tissue above 85°C and therefore is not adequate for soft tissue contraction at typical treatment speeds of 1cm/s used in a clinical setting. There were no distinguishable trends between the helium flow rate setting and internal and external tissue temperatures.