超声及磁共振成像法引导的低温外科手术

Ultrasound and Magnetic Resonance Imaging Guided Cryosurgery

实施低温外科手术的一个关键和难点是需要知道降温过程中组织冻结界面的实时位置及该界面上的降温或升温速率，以便及时调整冷刀方位及其冷量大小，从而达到冻伤病灶而保护健康组织的目的。在各种监测方法中，无损方法始终是医学和工程研究人员共同追求的目标。本文介绍了近期在低温外科手术中涌现出的几种主要的无损监测方法即超声成像(又分脉冲回波法和多普勒效应法)与磁共振成像方法，阐述了各方法的探测原理及其有关应用问题，并对其优、缺点进行了评述。

One of the major critical problems in the cryosurgery is to accurately monitor the moving front of the solid-liquid interface as well as the decreasing or increasing rate of the tissue temperatures, which can significantly help to regulate the orientation and the cooling power of the freezing probe and then to destroy the diseased tissues while preserving the healthy tissues from freezing injury. Among various approaches to monitor the cryosurgery, the noninvasive ones have been the objects for many researchers in both clinical and engineering fields. In this paper, several newly emerging methods for noninvasively monitoring the cryosurgery, i.e. the ultrasound imaging method (including pulse echography method and Doppler effect method) and the magnetic resonance imaging method were introduced. The monitoring principle, the advantages, the shortcomings, and the clinical applications for each of the methods are comprehensively compared and reviewed.