-Original-

Practical and Cost-Effective Use of Open-Surgery-Type Ultrasound Probes in Laparoscopic Hepatectomy: A Single-Center Experience with over 150 Cases

Yoichi Kawano¹, Yukio Ohshiro², Tetsuya Shimizu¹, Junji Ueda¹, Takahiro Murokawa¹, Yuto Aoki², Takashi Ono¹, Akira Hamaguchi¹, Toshiyuki Irie², Akihisa Matsuda¹, Akira Matsushita¹, Masato Yoshioka³, Nobuhiko Taniai³ and Hiroshi Yoshida¹

¹Department of Gastrointestinal Surgery, Nippon Medical School, Tokyo, Japan
²Department of Gastrointestinal Surgery, Nippon Medical School Chiba Hokusoh Hospital, Chiba, Japan
³Department of Gastrointestinal Surgery, Nippon Medical School Musashikosugi Hospital, Kanagawa, Japan

Background: Laparoscopic hepatectomy (Lap-H) is increasingly being performed in Japan, but the high cost and handling complexity of laparoscopic ultrasonographic (US) probes remain a barrier to its wider adoption. Intraoperative ultrasonography is essential for safe liver resection; however, specialized laparoscopic probes are expensive, have a limited field of view, and are difficult to manipulate.
Methods: To overcome these limitations, we developed a practical technique using an open-surgery-type microconvex US probe in Lap-H. The probe is inserted via an umbilical incision using a Lap Protector mini™ and EZ Access™, and probe manipulation is achieved through a cord-based control system. We applied this method in over 150 Lap-H cases before the introduction of a dedicated laparoscopic US system.
Results: This technique enabled the acquisition of axial and sagittal images with a wide and deep field of view, enhancing anatomical orientation and lesion visualization. There were no complications such as air leaks or equipment failure. The method allowed for the use of contrast-enhanced ultrasound and minimized interference with the operative field.
Conclusions: The use of open-surgery-type US probes in Lap-H offers a cost-effective, safe, and practical alternative to expensive laparoscopic US systems. This innovation may lower the barrier for institutions initiating Lap-H programs and promote the broader adoption of high-quality intraoperative ultrasonography in minimally invasive liver surgery.

J Nippon Med Sch 2026; 93: 60-66

Keywords
laparoscopic hepatectomy, intraoperative ultrasound, microconvex probe, surgical innovation, cost-effective technique

Correspondence to
Yoichi Kawano
y-kawano@nms.ac.jp

Received, July 24, 2025
Accepted, October 17, 2025