Tohoku J. Exp. Med., 2023 February, 259(2)

Bipolar Radiofrequency Ablation of the Adrenal Gland: In Vivo and Ex Vivo Experiments

Tomo Kinoshita,¹ Kazumasa Seiji,^1,2 Sota Oguro,¹ Yoshikiyo Ono,³ Ryo Morimoto,³ Fumitoshi Satoh³ and Kei Takase¹

¹Department of Diagnostic Radiology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
²Department of Diagnostic Radiology, South Miyagi Medical Center, Ogawara, Miyagi, Japan
³Department of Nephrology, Endocrinology and Vascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan

Laparoscopic adrenalectomy is currently the standard treatment modality for unilateral aldosterone-producing adenoma (APA); however, a less-invasive treatment is needed for its treatment. A new bipolar ablation system that poses a lower risk of complications has been recently developed. This study aimed to evaluate the safety and performance of a novel bipolar radiofrequency ablation (RFA) system for the treatment of APAs. Ablations were performed in an ex vivo study using bovine adrenal glands [group A: n = 6, single-probe; group B: n = 6, two probes, interprobe distance (ID) = 12 mm; group C: n = 6, two probes, ID = 20 mm]. The in vivo study was conducted in groups A and B (n = 2 each) using porcine adrenal glands. For the ex vivo study, the mean vertical diameter (Dv) of the coagulative necrosis area and the mean transverse diameter (Dt) values were 11.99 mm and 10.96 mm for group A, 12.66 mm and 10.0 mm for group B, and 23.37 mm and 22.10 mm for group C, respectively. For the in vivo study, the mean Dv and Dt values were 12.23 mm and 9.03 mm for group A, and 16.38 mm and 9.52 mm for group B, respectively. No heat-induced damage to the adjacent organs was observed. To our best knowledge, this is the first study to evaluate the performance of the bipolar system in RFA of the adrenal gland. RFA using the new bipolar ablation system is safe and produces a sufficient coagulation area to treat APAs.

Keywords —— aldosterone-producing adenoma; animal study; primary aldosteronism; radiofrequency ablation; secondary hypertension

© 2023 Tohoku University Medical Press

===============================

Tohoku J. Exp. Med 2023, 259, 127-133.

Correspondence: Sota Oguro, Department of Diagnostic Radiology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8574, Japan.

e-mail: sota.oguro.c8@tohoku.ac.jp