T2 relaxometry of the hippocampus at 3T
T2 relaxometry of the hippocampus at 3T
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DOI：
10.3174/ajnr.a0505
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发表时间：
2007-06-01
影响因子：
3.5
通讯作者：
Duncan, J. S.
中科院分区：
文献类型：
--
作者：
Bartlett, P. A.;Symms, M. R.;Duncan, J. S.
背景和目的：T2标测有助于识别和量化海马和杏仁核的异常。这是特别有用的术前评估颞叶癫痫患者和识别双侧海马硬化（HS）。本研究的目的是实施和验证一种双回波方法，用于在3 T MR成像扫描仪上产生完全覆盖海马和大脑其余部分的冠状T2图。材料和方法：T2弛豫时间在3次质量评估Eurospin II上估计了10次（诊断声纳，Livingstone，Scotland）在3 T Excite MR成像扫描仪上使用常规自旋回波（CSE）、快速自旋回波和快速恢复快速自旋回波（FRFSE）序列的测试对象（GE Healthcare，密尔沃基，威斯康星州）。然后测量15名健康受试者和20名有明确HS的受试者的海马T2弛豫时间，这些受试者在1.5T下使用先前验证的双回波CSE序列和3 T下使用FRFSE序列进行扫描。健康志愿者和HS受试者海马T2测量的可靠性良好。FRFSE图像适用于定性放射学报告，并具有完整的脑覆盖，因此不需要额外的T2加权序列。3 T海马T2测量值与先前验证的1.5T技术获得的值之间存在良好的相关性，可可靠识别所有HS受试者。使用FRFSE 30/80序列的T2标测可以容易地在3 T下应用，并且可以在体内产生可靠的T2值，扫描时间为3分1秒，而1.5T下CSE序列的扫描时间为10分30秒。
BACKGROUND AND PURPOSE: T2 mapping is useful for identifying and quantifying abnormalities of the hippocampus and annygdala. It is particularly useful in the presurgical evaluation of patients with temporal lobe epilepsy and for the identification of bilateral hippocampal sclerosis (HS). The purpose of this study was to implement and validate a dual-echo method for producing coronal T2 maps with complete coverage of the hippocampus and the rest of the brain on a 3T MR imaging scanner.MATERIALS AND METHODS: T2 relaxation times were estimated on 10 occasions on 3 quality assessment Eurospin II (Diagnostic Sonar, Livingstone, Scotland) test objects with the use of conventional spin-echo (CSE), fast spin-echo, and fast recovery fast spin-echo (FRFSE) sequences on a 3T Excite MR imaging scanner (GE Healthcare, Milwaukee, Wis). Hippocampal T2 relaxation times were then measured in 15 healthy subjects and 20 subjects with clear-cut HS who were scanned at 1.5T with a previously validated dual-echo CSE sequence and 3T with an FRFSE sequence.RESULTS: 3T FRFSE data were as reliable as CSE data at 1.5T. Reliability of hippocampal T2 measures was good on healthy volunteers and subjects with HS. FRFSE images were suitable for qualitative radiologic reporting and with complete brain coverage, so no additional T2-weighted sequences were required. There was good correlation between the 3T hippocampal T2 measurements and values obtained with the previously validated technique at 1.5T, with reliable identification of all of the subjects with HS.CONCLUSIONS: T2 mapping with an FRFSE 30/80 sequence may be readily applied at 3T and can produce reliable T2 values in vivo with contiguous 5-mm sections and in a much reduced scan time of 3 minutes 1 second compared with 10 minutes 30 seconds for the CSE sequence at 1.5T.