Microwave thermolysis of sweat glands.

BACKGROUND AND OBJECTIVES Hyperhidrosis is a condition that affects a large percentage of the population and has a significant impact on peoples' lives. This report presents a technical overview of a new noninvasive, microwave-based device for creating thermolysis of sweat glands. The fundamental principles of operation of the device are presented, as well as the design and optimization of the device to target the region where the sweat glands reside. MATERIALS AND METHODS An applicator was designed that consists of an array of four waveguide antennas, a cooling system, and a vacuum acquisition system. Initially, the performance of the antenna array was optimized via computer simulation such that microwave absorption was maximized near the dermal/hypodermal interface. Subsequently, hardware was implemented and utilized in pre-clinical testing on a porcine model to optimize the thermal performance and analyze the ability of the system to create thermally affected zones of varying size yet centered on the target region. RESULTS Computer simulation results demonstrated absorption profiles at a frequency of 5.8 GHz that had low amounts of absorption at the epidermis and maximal absorption at the dermal/hypodermal interface. The targeted zone was shown to be largely independent of skin thickness. Gross pathological and histological response from pre-clinical testing demonstrated the ability to generate thermally affected zones in the desired target region while providing protection to the upper skin layers. CONCLUSIONS The results demonstrate that microwave technology is well suited for targeting sweat glands while allowing for protection of both the upper skin layers and the structures beneath the subcutaneous fat. Promising initial results from simulation and pre-clinical testing demonstrate the potential of the device as a noninvasive solution for sweat gland thermolysis.