大脑中动脉M1段分叉部的显微解剖及临床意义

Microanatomy of M1 bifurcation of middle cerebral artery and clinical significance

目的:研究大脑中动脉M1分叉部的体表投影及不同头位下M1分叉部与侧裂浅表静脉的关系,为经侧裂入路手术提供空间量化参考数据。方法:在30侧(15例)用甲醛溶液固定的湿性成人头颅标本上,用红色乳胶灌注双侧颈内动脉和椎动脉,分别从左右翼点入路开颅,在标本上确定坐标轴,测量M1分叉部在此坐标系投影的数值。观测不同头位下M1分叉部和侧裂浅表静脉的关系,并测量M1分叉部与侧裂浅表静脉之间的垂直距离。结果:M1分叉部投影左侧x值为(26.56±3.03)mm,y值为(46.71±4.24)mm;右侧x值为(27.03±2.92)mm,y值为(45.48±4.20)mm。在以x=25.0 mm、y=45.0 mm为圆心,10 mm为半径画成圆的范围内共有M1分叉部的投影27侧,占90.00%。尸头向对侧旋转30°时,M1分叉部均在侧裂浅表静脉的额侧,旋转60°时左侧4例、右侧5例M1分叉部位于侧裂浅表静脉的额侧,其余均在侧裂浅表静脉的下方。M1分叉部与侧裂浅表静脉之间的垂直距离左侧为(14.60±2.27)mm,右侧为(15.03±2.36)mm。结论:M1段真正分叉总在岛阈的最高处,M1分叉部与侧裂浅表静脉之间的关系和头位密切相关。

Objective： To research on the surface projection of the bifurcation of M1,and the relationship between the M1 bifurcation and the superficial sylvian veins;on purpose it could offer reference data and space quantification concepts for operations operated trough lateral fissure.Methods： On 30 samples of adult heads fixed with formaldehyde solution,we used red latex to pour into the bilateral internal carotids and vertebral arteries,and undertook pterion approach from the left and right separately.We set a coordinate axe on the samples,and measured the number of the projection of the M1 bifurcation on this coordinate.We observed the relationships between the M1 bifurcation and the superficial sylvian veins under different head positions,and measured the vertical distance between them.Results： The projection of the M1 bifurcation was： x-axis of the left（26.56 ± 3.03） mm;y-axis of the left（46.71 ± 4.24） mm;x-axis of the right（27.03 ± 2.92） mm;y-axis of the right：（45.48 ± 4.20） mm.In a circular range with a center located at x = 25.0 mm and y = 45.0 mm,and a radius of 10 mm,there were 27 samples of projections of M1 segment（90.00%）.When the head was turned by 30° toward the opposite side,the M1 bifurcations all lay in the lateral of the superficial sylvian veins,and when turned by 60°,there were 4 samples that lay in the left and 5 samples in the right of the lateral of the superficial sylvian veins,and the rest all lay below the superficial sylvian veins.The vertical distance between the M1 bifurcation and the superficial sylvian vein was： left（14.60 2.27） mm;right（15.03 2.36） mm.Conclusions： The real bifurcation of the M1 segment always lies on the top of the limen of insula.The relationship between the M1 bifurcation and the superficial sylvian vein is closely related to the head position.