丘脑长度比例法定位丘脑腹中间核的核磁共振成像解剖学研究

A MRI anatomic study of locating ventro-intermediate nucleus based on thalamic length-ratio

目的通过对正常人丘脑解剖特征的测量与分析,探讨采用丘脑长度比例法测量、计算丘脑腹中间核(Vim)坐标的可行性。方法采用1.5T高清晰核磁共振成像仪(MRI)仪测量了82例正常成人大脑前后联合间径(AC-PC)、大脑长度与宽度、丘脑长度与宽度、两侧丘脑间的夹角,分析AC-PC与大脑长度、大脑宽度、丘脑长度、丘脑宽度及两侧丘脑间夹角之间的相关性,分别通过丘脑长度比例法和原点法(根据AC-PC中点)测算Vim核的坐标,并比较两种方法所得结果的差异。结果AC-PC22.5±1.1mm,丘脑长33.1±1.4mm,丘脑宽17.5±1.2mm,两侧丘脑间的夹角51.0±6.0°;左右丘脑长、宽无统计学差异,但个体差异明显:不同个体丘脑长度的最大差为7.4mm,丘脑宽度的最大差为5.9mm;AC-PC与脑长、丘脑长呈正相关;两侧丘脑间的夹角同脑形、脑宽呈正相关性;原点法测得的Vim核位置偏后,而丘脑长度比例法确定的Vim核的Y值变异较大。结论可根据丘脑长度来测算Vim核坐标,丘脑长度比例法较原点法确定的Vim坐标更加个性化。

Objective To analyze the possibility of locating the ventro-intermediate nucleus （Vim） based on thalamic length-ratio. Methods The thalamic lengths and width, cerebral length and width, the angle between left and right thalamus were measured in the plane 4 mm above the AC-PC line in axial proton MR image, and the inter-commissural line （AC-PC） was measured in Tl-weight sagittal MR image, and the relations between thalamic parameters and cerebral parameters and AC-PC were analyzed in 82 healthy Chinese volunteers, aged from 20- 69 years old. The Y-coordination of Vim based on thalamic length-ratio was compared with that based on the middle point of AC-PC line. Results The AC-PC was 22. 5±1.1 mm （19. 8±24. 5mm） ; The thalamic length was 33. 1±1.4 mm （29.1±36. 5mm） and the thalamic width was 17. 5±1.2 mm （14. 2±20. 1 mm） ; The angle between left and right thalamus was 51.0±6.0 degree; There are no significant differences in the thalamic length and width between the left and right; and there is no significant difference between different age groups. But the individual differences are significant： the max difference between different individuals was 7. 4 mm in thalamic length and 5.9 mm in thalamic width. There are positive correlations between AC-PC and thalamic lengths as well as cerebral length. The Y coordinate of Vim nucleus was more posterior （2.0!l. 7ram,P=0. 000） located according the middle of AC-PC line, while it was more variation located with thalamic length-ratio. Conclusion The new method for locating Vim nucleus based on thalamic length-ratio is convenient and accurate, and more individualization.