正常国人双侧大脑中动脉分叉角度测量及脑动脉瘤形成、发展因素的相关性研究

Measurement of bilateral M1 bifurcation angle of middle cerebral artery and development of cerebral aneurysm

目的：测量双侧大脑中动脉M1分叉角度，探讨其正常值范围及与年龄和性别的相关性研究，分析脑动脉瘤形成、发展因素的相关性。方法以40例大脑中动脉动脉瘤组及195例对照组的MRA资料为研究对象，进行双侧大脑中动脉分叉角度测量，结果采用百分比法和Correlation相关性分析，统计95％可信区间以及夹角和性别、年龄及侧别的相关性。结果因为所测夹角数据呈非正态分布，故采用百分位数法计算95％正常值范围。男性左侧MCA夹角58．52～128．40°，男性右侧MCA夹角60．20～132．20°；女性左侧MCA夹角51．63～127．50°，女性右侧MCA 夹角65．38～155．38°；Correlation 相关性分析结果：双侧MCA夹角（左侧MCA 夹角56．90～128．00°；右侧MCA夹角62．00～144．00°）（ r＝0．321，p＝0．000）差异有统计学意义。秩和检验双侧MCA夹角有差异（ Z＝－2．641，P＝0．008）。 MCA夹角与年龄之间为正相关（左右侧r分别为0．248、0．210，P＜0．01）；与性别之间无相关性（左右侧r分别为0．135、0．085，P＞0．05）。动脉瘤组和对照组秩和检验显示动脉瘤组夹角和对照组夹角间有显著差异（左右侧Z值分别为-6．357、-7．452，P＜0．01），含有动脉瘤的分叉角度明显高于对照组的分叉角度。结论 MCA夹角与年龄有关，呈正相关，年龄越大，夹角有增大趋势；与性别无相关性。左侧MCA夹角大于右侧MCA夹角。动脉分叉角度对分叉部动脉瘤的检出及预测具有重要参考价值。

ObjectiveTomeasuretheangleoftheM1birurcationofmiddlecerebralarteryandinvestigatethe correlation between its normal range , age and gender .Methods The MRA data from 40 cases with the aneurysm of MCA and 195 cases from the control group were investigated ..The bilateral bifurcation angle of middle cerebral artery was measured .The method of percentiles and the correlation analysis were used to determine the 95%confidence interval and the correlations of the angle ,gender,age and side.Results The method of percentiles was used to calculate the 95%normal ranged due to the skewed distribution of the obtained angle data .The left MCA angle was 58. 52°to 128.40°in males.The right MCA angle was 60.20°to 132.20°in males.The left MCA angle was 51.63°to 127. 50°in females.The right MCA angle was 65.38°to 155.38°in females.For the results of correlation analysis , there was significant differences between the bilateral MCA angles （ left MCA angle between 56.90°and 128.00°and right MCA angle between 62.00°and 144.00°） （ r=0.321,P=0.000） .The rank test showed that there were differences in the MCA angles at the two sides （z=2.641, p=0.008）.The result of correlation analysis indicated that there was a positive correlation between the MCA angle and the age （ The left and right side of the r are respectively 0.248, 0.210,p〈0.01） . There was no correlation with gender （ The left and right side of the r are respectively 0.135, 0.085,p〈0.05） .As shown by the rank test results , there was significant differences between the aneurysm group and control group in angle of arterial bifurcation .（ The left and right side of the r are respectively-6.457,-7.452,p〈0.01） The angle is significantly higher in aneurysm containing arterial bifurcations than those in the control group .Conclusion There are positive correlations between MCA angle and age .The angle is expanding with the growing of age .There is no correlation with gender.The MCA angle at the left side is larger than that at the right .The angle of arterial bifurcation is of great value as a reference for the testing and the prediction of aneurysm.