正常及癫痫状态下杏仁复合体-海马结构的弥散张量成像对比

Comparative study of diffusion tensor imaging of amygdale-hippocampus in patients with temporal lobe epilepsy and normal controls

目的使用磁共振弥散张量成像(DTI)及白质纤维束示踪技术分析杏仁复合体-海马结构在正常生理及癫痫状态下DTI参数及白质纤维束分布变化特点,评价DTI技术在杏仁复合体-海马结构中的应用价值。方法对16例临床诊断颞叶癫痫(TLE)患者和20例正常志愿者进行常规MRI和DTI扫描,分别测量其双侧颞叶杏仁复合体、海马头部、海马体部及海马尾部的部分各向异性(FA)、相对各向异性(RA)、表观弥散系数(ADC)等数值并进行统计学分析,同时观察白质纤维束走向、分布情况;并对两者作对比。结果正常志愿者双侧颞叶杏仁复合体、海马结构DTI参数差异无统计学意义。TLE患者ADC值变异度以杏仁复合体、海马尾部最显著,而FA、RA值变异度则以海马头部、体部较明显。结论 DTI技术能较常规MRI提供更全面及细微的颞叶杏仁复合体-海马结构信息,通过对局部弥散参数和白质纤维束变化特点的研究,进一步了解颞叶癫痫状态下海马与毗邻结构的继发改变;为进一步提高TLE病变的诊断及制定治疗方案提供有用的信息。

Objective To investigate the diffusion tensor imaging （DTI） characteristics of amygdala and hippocampus in patients with temporal lobe epilepsy （TLE） and the normal controls, in order to evaluate the application of the DTI in the diagnosis of TLE. Methods Sixteen patients with TLE and 20 healthy volunteers received conventiorial MRI and DTI scanning. The ADC, FA and RA of bilateral amygdalae and hippocampi were measured, respectively. The distribution of the white matter fiber tracts was observed and compared. Results No significant differences in DTI parameters were noted between the bilateral amygdalae or hippocampi in normal controls. Patients with TLE had increased ADC and decreased FA and RA. While noticed variability of ADC in amygdale and caudal hippocampus, as well as variability of FA and RA in the hippocampus head and body, was observed in patients with TLE. Conclusion DTI provides more comprehensive and detailed structure information in amygdala and hippocampus than the conventional MRI. Through the research of the local white matter fiber tracts and its parameters, DTI can provide useful information for the diagnosis and treatment of TLE.