Original Research
Copyright ©The Author(s) 1997. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 15, 1997; 3(3): 134-136
Published online Sep 15, 1997. doi: 10.3748/wjg.v3.i3.134
Ultrastructural observation of liver tissue ablation induced by high-intensity focused ultrasound
Shu-Qun Cheng, Xin-Da Zhou, Zhao-You Tang, Yao Yu, Su-Su Bao, De-Chu Qian
Shu-Qun Cheng, Xin-Da Zhou, Zhao-You Tang, Yao Yu, Liver Cancer Institute, Zhongshan Hospital, Shanghai Medical University, Shanghai 200032, China
Su-Su Bao, De-Chu Qian, Biomedical Ultrasound Laboratory, Shanghai Jiaotong University, Shanghai 200030, China
Author contributions: All authors contributed equally to the work.
Correspondence to: Shu-Qun Cheng, MD, PhD, Liver Cancer Institute, Zhongshan Hospital, Shanghai Medical University, Shanghai 200032, China
Telephone: +86-21-65564166-72833
Received: November 1, 1996
Revised: January 8, 1997
Accepted: February 10, 1997
Published online: September 15, 1997
Abstract

AIM: To observe the ultrastructural changes of liver tissues on normal rabbit ablated by high-intensity focused ultrasound (HIFU).

METHODS: A single shot of 1.1 MHz focused ultrasound at an intensity of 500 W/cm2 with 20-s duration of continuous exposure was applied intraoperatively in normal rabbit livers. Ultrastructural changes of the sonoablated lesion, as viewed by light and electron microscopy, were observed.

RESULTS: Liver cells at the center of the sonoablated lesion showed irreversible degeneration immediately after HIFU treatment; electron microscopy showed that although the liver cells appeared normal histologically, irregularly shaped cavities of about 0.3-0.5 μm in diameter were present in the cytoplasm.

CONCLUSION: Thermal damages may be the main mechanism of HIFU-induced ablation of liver tissues besides cavitation effect.

Keywords: Liver/ultrastructure, Ultrasonic therapy, Eletron microscopy