正常人颈动脉超声的临床意义

Detection of carotid by ultrasound in normal subjects

目的 :研究不同年龄组正常人颈动脉超声的特点。 方法 :将 2 5 0名正常人按年龄分为Ⅰ (31～ 4 0岁 )、Ⅱ(4 1～ 5 0岁 )、Ⅲ (5 1～ 6 0岁 )、Ⅳ (6 1～ 70岁 )、Ⅴ (>70岁 )五组。运用二维彩色多普勒超声技术 (2D CDUS)检测每组受检者左右颈总动脉共 5 0 0支 ,测量颈总动脉管腔内径、内中膜厚度 (IMT)、最大剪切率 (SR)等部分血流动力学参数。 结果 :①正常人颈动脉内径随年龄增长而增宽 ,其中Ⅰ、Ⅱ、Ⅲ组组间比较无明显差异 ,Ⅳ组与Ⅰ、Ⅱ组比较及Ⅴ组与Ⅰ、Ⅱ、Ⅲ组比较差异显著 (P <0 .0 5或P <0 .0 1) ,Ⅳ、Ⅴ组间无明显差异。②当年龄 >5 0岁时 ,IMT出现不同程度的增厚 (P <0 .0 5 ) ,斑块检出率与年龄呈正比。③血流速度Ⅲ组较Ⅰ组 ,Ⅳ组较Ⅰ、Ⅱ组 ,Ⅴ组较第Ⅰ、Ⅱ、Ⅲ组明显下降 (P <0 .0 5或P <0 .0 1)。④颈总动脉最大SR各组右侧略大于左侧 ,但无统计学意义 ,双侧最大SR随年龄增长而减低 ,Ⅳ组较Ⅰ、Ⅱ组 ,Ⅴ组较前三组差异显著 (P <0 .0 5 )。⑤各组间阻力指数 (RI)、搏动指数(PI)无显著差异。结论 :正常人随年龄增长颈动脉内径增宽 ,血流速度下降 ,IMT增加 ,SR降低 ,年龄增长可能是颈动脉粥样硬化的危险因素之一。

Objective:To investigate the ultrasonic characteristics of carotids in the subjects with different age. Methods: According to the age , 250 cases were divided into five groups:group Ⅰ(31-40 y),Ⅱ(41-50 y),Ⅲ(51-60 y),Ⅳ(61-70 y),Ⅴ(>70 y).Five hundred common carotids were assessed in 250 healthy subjects using two-dimentional color Doppler ultrasound (2D-CDUS).The diameter(D),intimal medial thickness(IMT), hemodynamics parameters including shear rate(SR) were recorded. Results:The diameter of normal carotids increased along with age, there was no significant difference among groupⅠ, Ⅱ, Ⅲ and between group Ⅳ, Ⅴ; Respectively compared with group Ⅰ,Ⅱand groupⅢ, the D of group Ⅳ, Ⅴ increase significantly(P<0.05 or P<0.01). For subjects with age more than 50 years,IMT was remarkably thicker than those who were less than 50years(P<0.05) , plaque event rate was in direct proportion to the age.The blood flow velocity decreased gradually in groupⅢ, Ⅳand groupⅤ(P<0.05 or P<0.01). The maximum SR of left carotid was a little higher than that of the right. SR of bilateral carotid reduced by the increasing age. Compared with group Ⅰ,Ⅱ, SR of groupⅣ decreased remarkably. There was also significant difference between group Ⅴ and groupⅠ,Ⅱ,Ⅲ(P<0.05). Resistance index(RI) and pulsatility index(PI) were not significantly different in different age groups. Conclusion: The caliber of carotid was enlarged , the blood flow velocity decreased,the IMT thickened gradually and the maximum SR reduced with increasing age.