MRI TOOLS FOR FOCAL SPOT VISUALIZATION DURING FUS BREAST TREATMENT

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 介绍 在乳腺MRI引导聚焦超声治疗的计划阶段，病灶的实际位置是 通过使用质子共振频率（PRF）测温法对低温测试点进行可视化验证。但在 胖PRF变得不可靠。替代方法基于快速自旋回波（FSE）的T1加权成像[1] 和位移成像与MR-ARFI。本研究的目的是评估这两种方法在人类离体乳腺癌 组织. 方法 对于6个病灶位置，使用MR-ARFI和FSE进行超声成像。对于FSE，重复时间（TR）为 各种各样。在配备有HIFU系统的3T MRI扫描仪上进行成像，并且定时使得声处理 扫描同时结束使用MR-ARFI位移图分析焦点处信号的SNR， FSE幅度差图像。 要了解卢卡斯中心正在进行的其他项目，请访问www.example.com （卢卡斯年度报告和 ISMRM 2011摘要）

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Introduction During the planning stage of MRI-guided focused ultrasound treatments in breast, the actual location of the focus is verified by visualization of a low temperature test spots using proton resonance frequency (PRF) thermometry. However, in fat PRF becomes unreliable. The alternative approaches are based on T1-weighted imaging with fast spin-echo (FSE) [1] and on displacement imaging with MR-ARFI. The goal of this study was to evaluate both methods in human ex vivo breast tissue. Methods For six focal locations, imaging was performed with ultrasound, using MR-ARFI and FSE. For FSE, repetition time (TR) was varied. Imaging was performed on a 3T MRI scanner equipped with a HIFU system, and timed such that the sonications and the scans ended at the same time. SNR of the signal at the focus was analyzed using MR-ARFI displacement maps and FSE magnitude difference images. To read about other projects ongoing at the Lucas Center, please visit http://rsl.stanford.edu/ (Lucas Annual Report and ISMRM 2011 Abstracts)