颅内血肿的低场MRI表现--转

老*驼

【摘要】  目的：探讨颅内血肿的低场MRI表现。方法：对67例颅内血肿患者MRI片进行回顾性分析。结果：急性期血肿于T1WI呈低、等信号，T2WI呈高、等信号。GRET2*WI序列均呈低信号。亚急性早期血肿T1WI仍呈等、低信号，T2WI均呈高及略高信号。亚急性中期T1WI出现典型外周环状高信号，中间等、低信号，T2WI仍呈高及略高信号。亚急性晚期T2WI呈明显均匀高信号，T1WI多数为外周环状高信号，中间等低信号或均匀高信号。慢性期血肿逐渐演变成液化灶，呈均匀长T1、长T2信号。结论：颅内血肿急性期、亚急性各期及慢性期在低场MRI上均能较好显示病变特点，具有特征性。
【关键词】  颅内血肿 低场 磁共振 影像
　　Study on Low Field MRI Image on Intracranial Hematoma


    Abstract: Objective：To study the low field MRI image on intracranial hematoma. Method: We reviewed MRI datas on 67 cases intracranial hematoma. Result: MRI exhibited signal intensity of acute and subacute or chronicity premature hematoma. That's hematomas during acute period shoued hypointense and equal signal intensity on T1-weighted images and hyperintense and T2-weighted images equal signal intensity. GRE T2*WI was hypointense. Insubacute period which showed hypointense and equal signal intensity on T1WI and hyperintense on T2WI.In the mid-term of subacute period showed T2WI hyperintense typical hyperintense in pe**heral annular, equal and hypointense in central area. In late subacute period showed obviously hyperintense on T2WI, most of hpyerintense on T1WI in pe**heral annular, equal signal intensity or hyperintense in central area. Hematomas resulted in liquefaction in chronicity, with long T1,T2 signal. Conclusion: There's typical feature on MRI of intracranial hematorma in acute and subacute or chronic period.
    Key words:  Intracranial hematoma;  Low field;  MRI;  Image
　　影像学检查是诊断颅内血肿的重要方法，其中CT对于急性颅内血肿的诊断有重要价值。由于血肿在高低场强磁共振中的表现有较大差异，笔者总结本院67例颅内血肿的各期在低场磁共振中不同序列的表现特点，探讨其信号演变规律，以提高低场磁共振对于此类疾病的诊断价值。
　　1  材料与方法
　　1.1  材料：搜集自2004年4月至2007年3月我院收治的67例颅内血肿患者的CT和MRI资料。男45例,女22例,年龄18～84岁,平均年龄51岁。本组资料中超急性期0例。急性期（＜48h）24例，亚急性早期（3～5d）17例，亚急性中期（6～10d）11例，亚急性晚期（10～21d）9例、慢性期（21d至数月）6例。
　　1．2  方法：急性期病例行MRI检查并与CT结果比对确认。亚急性各期、慢性期病例均单行MRI检查。有两位副主任医师阅片，意见一致为诊断标准。


　　美国GE0.35T signa ovation MRI机,常规扫描程序为  横轴位FSET2WI, T1FLAIR  FSE—IR GRET2*WI序列


　　CT扫描采用：岛津—4500T,扫描层厚10mm,共扫十层,疑为后颅窝病变做2～5mm薄扫。