title: Electromagnetic Initiation and Propagation of Bipolar Radiofrequency Tissue Reactions via Invasive Non-Insulated Microneedle Electrodes.
abstract: Radiofrequency (RF) energy can be emitted into the skin, either non- or invasively, via a monopolar mode that utilizes an active electrode and a grounded electrode or via a bipolar mode that employs two active electrodes. In this experimental study of RF tissue reactions, bipolar RF energy was emitted in vivo to micropig skin at varying microneedle penetration depths, signal amplitudes, and conduction times. Immediately after RF treatment, skin samples exhibited RF-induced coagulation columns of thermal injury, separately generated around each microneedle in the dermis. In ex vivo bovine liver tissue, the thermal coagulation columns were found to be concentrated maximally around the pointed tips of each electrode. After a RF conduction time of 2 seconds, the individual areas of thermal coagulation began to converge with neighboring RF-induced coagulation columns; the convergence of coagulation columns was found to start from the tips of neighboring electrodes.
authors.affiliation: Department of Anatomy, Soonchunhyang University College of Medicine, Cheonan, Korea.
authors.forename: Jongju
authors.initials: J
authors.lastname: Na
authors.affiliation: Department of Dermatology and Cutaneous Biology Research Institute, Yonsei University College of Medicine, Seoul, Korea.|Department of Dermatology, Yanbian University Hospital, Yanji, China.
authors.forename: Zhenlong
authors.initials: Z
authors.lastname: Zheng
authors.affiliation: Department of Dermatology, University of California, School of Medicine, San Francisco, CA, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Dannaker
authors.affiliation: Department of Dermatology and Cutaneous Biology Research Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sang Eun
authors.initials: SE
authors.lastname: Lee
authors.affiliation: Kangskin Dermatology Clinic, Seoul, Korea.
authors.forename: Jin-Soo
authors.initials: JS
authors.lastname: Kang
authors.affiliation: Department of Dermatology and Cutaneous Biology Research Institute, Yonsei University College of Medicine, Seoul, Korea.|Kangskin Dermatology Clinic, Seoul, Korea.
authors.forename: Sung Bin
authors.initials: SB
authors.lastname: Cho