Okada S, Kawakatsu M, Suzuki H, Igarashi Y, Ito T, Kato T, Kaieda R, Ming N G
Department of Radiology, Nippon Medical School First Hospital.
Nihon Igaku Hoshasen Gakkai Zasshi. 1990 Aug 25;50(8):938-45.
We performed 67 examinations in 27 patients with intracerebral hemorrhage on a 0.2T permanent magnet system. MR appearance of the hematomas on T-1 weighted and T-2 weighted images (T1WIs, T2WIs) was carefully evaluated according to the chronological course of the lesions after the ictus. The signal intensity of each hematoma was classified into four stages in terms of the degradation process of hemoglobin. Four hematomas examined within 24 hours after the ictus (ultra-acute stage) appeared slightly hypointense or isointense relative to the normal brain tissue on T1WIs and markedly hyperintense on T2WIs. Three of those lesions became partially or totally hypointense on T2WIs at the acute stage (one to three days after the ictus), though all appeared in general isointense on T1WIs. The hematomas at the subacute stage (four days to two weeks after the ictus) were hyperintense on both T1WIs and T2WIs. At the chronic stage (more than two weeks after the ictus) the signal pattern of hematomas became variable: hyperintense on both T1WIs and T2WIs early at this stage; hypointense on T1WIs but mostly hyperintense on T2WIs latter. The results indicate the clinical feasibility of a low tesla system for MR evaluation of intracerebral hematomas.
我们使用0.2T永磁系统对27例脑出血患者进行了67次检查。根据发病后病变的时间进程，仔细评估了血肿在T1加权像（T1WI）和T2加权像（T2WI）上的磁共振成像表现。根据血红蛋白的降解过程，将每个血肿的信号强度分为四个阶段。发病后24小时内检查的4个血肿（超急性期）在T1WI上相对于正常脑组织呈轻度低信号或等信号，在T2WI上呈明显高信号。其中3个病变在急性期（发病后1至3天）T2WI上变为部分或完全低信号，尽管在T1WI上总体呈等信号。亚急性期（发病后4天至2周）的血肿在T1WI和T2WI上均为高信号。在慢性期（发病后超过2周），血肿的信号模式变得多样：在此阶段早期，在T1WI和T2WI上均为高信号；后期在T1WI上为低信号，但在T2WI上大多为高信号。结果表明低场强系统用于脑内血肿磁共振评估的临床可行性。
