中文摘要：

目的：通过研究脊髓小脑共济失调3型（SCA3/MJD）患者小脑蚓部、桥臂、小脑皮质、齿状核的氢质子磁共振波谱（1H-MRS）的特点,探讨1H-MRS评估SCA3型疾病严重程度的价值。方法：对36例SCA3/MJD患者与27例性别、年龄与之匹配的健康对照进行单体素1H-MRS测定,比较2组间小脑上述各脑区N-乙酰天门冬氨酸（NAA）/肌酸（Cr）,胆碱（Cho）/Cr,NAA/Cho比值的差别;同时对34例患者进行MJD1基因中（CAG）n重复次数的测定,应用共济失调等级量表（SARA）对其进行评分,并结合上述各脑区代谢物比值进行相关性分析。结果：SCA3/MJD患者的SARA评分与其病程、发病年龄、CAG重复次数呈正相关,与发病年龄呈负相关;SCA3/MJD患者上述各脑区NAA/Cr值及齿状核、蚓部NAA/Cho值较正常对照明显降低（P〈0.01）;SCA3/MJD患者小脑各区的1H-MRS与病程、发病年龄、CAG重复次数、SARA评分存在相关性。结论：1H-MRS技术可以检测SCA3/MJD患者小脑的神经代谢改变,且可较好地反应SCA3/MJD的疾病严重程度。

英文摘要：

Objective To evaluate the metabolite pattern and the severity in patients with spinocerebellar ataxia type 3/ Machado-Joseph disease（SCA3/MJD） by 1H magnetic resonance spectroscopy（1H-MRS） on different cerebellar regions,including cerebellar vermis,cerebellar peduncles,cerebellar cortex,and dentatum.Methods Thirty-six SCA3/MJD patients,and 27 sex,age-matched healthy controls were scanned with 1H-MRS for N-acetylaspartate（NAA）,choline（Cho） and creatine（Cr）.We made cerebellar vermis,cerebellar peduncles,cerebellar cortex,and dentatum as the region of interests（ROI）,and finally got access to NAA/Cr,Cho/Cr,and NAA/Cho ratios.We also examined the CAG repeat numbers of MJD1 gene,scored the 36 patients by the scale for the assessment and rating of ataxia（SARA）,analyzed the differences in ratios between SCA3/MJD patients and the control group,and explored whether relevance existed between these ratios and duration of the disease,age of onset,CAG repeat times,and SARA scores respectively.Results The ratio of NAA/Cr in SCA3/MJD patients showed a significant reduction in the cerebellar cortex,dentatum,cerebellar vermis and medipeduncle（P0.01） compared with the controls.The ratio of NAA/Cho also showed significant reduction in the dentatum and cerebellar vermis（P0.01）.A number of correlations were found between the metabolite ratios of 1H-MRS and duration of the disease,age of onset,expanded CAG and SARA score in SCA3/MJD patients.Conclusion 1H-MRS,which shows the neural metabolic changes in the cerebella of SCA3/MJD patients,provides useful information about the severity of SCA3/MJD.