学术交流 产品简介 诚征代理 联系我们 国内外进展 我们的服务



Cryobiology 1999 May;38(3):250-9                    Related Articles, Links

Imaging of interstitial cryotherapy--an in vitro comparison of ultrasound, computed tomography, and magnetic resonance imaging.

Tacke J, Speetzen R, Heschel I, Hunter DW, Rau G, Gunther RW.


Department of Diagnostic Radiology, University of Technology, Aachen, Germany. tacke@rad.rwth-aachen.de

RATIONALE AND OBJECTIVES: To evaluate the imaging capabilities of ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) in monitoring interstitial cryotherapy and to compare them with visual control. METHODS: An experimental MR-compatible, vacuum-insulated and liquid nitrogen-cooled cryoprobe was inserted under in vitro conditions into a porcine liver, which was kept at a temperature of 37 +/- 1 degrees C, in a water bath with continuous stirring. The freezing procedure was controlled macroscopically, by US (Toshiba Sonolayer, 7.5-MHz linear array transducer), by CT (Siemens Somatom Plus, slice thickness 2-8 mm, 165-210 mA at 120 kV), and by MRI (Philips Gyroscan ACS-NT, FFE TR/TE/FA = 15/5.4/25 degrees, T1-SE 550/20, T2-TSE 1800/100) after the iceball reached its maximum size. RESULTS: The maximum iceball diameter around the probe tip was 12.0 mm by visual control, 12.4 mm by US, 12.7 mm by CT, and within 12.8 mm by spin echo sequences and 11 mm by gradient echo sequence. Due to the nearly signal-free appearance of the frozen tissue on MR images, the ice/tissue contrast on T1-weighted and gradient echo images was superior to T2-weighted images and CT images. Sonographically, the ice formation appeared as a hyperechoic sickle with nearly complete acoustic shadowing. CONCLUSION: Due to the better ice/tissue contrast, T1-weighted or gradient echo MR images were superior to CT and US in monitoring interstitial cryotherapy. Gradient echo sequences generally underestimated the ice diameter by 15%. Copyright 1999 Academic Press.

PMID: 10328915 [PubMed - indexed for MEDLINE]

 

©2009 版权所有 中美医疗有限公司
e-mail: sino-usmed@cryocare.com.cn
设计制作:全程