应用CTA图像分析颈椎钩突及上关节突对椎动脉的影响

目的：分析椎动脉与相邻颈椎（C）钩突及上关节突的关系,对钩突增生影响椎动脉的程度进行初步判定.方法：按纳入标准选取行颈CTA检查的患者61例.沿椎动脉走行方向分别对左、右侧椎动脉行多平面重组,在冠状面观察钩突与相邻椎动脉的关系,通过旋转重组后图像的角度得到上关节突的矢状面图像并观察上关节突与邻近推动脉的关系.C3～C7处冠状面测量钩突突向椎动脉最外点到颈椎中线的距离（L）、钩突所在稚体中份宽度一半（M）,并计算L/M值.依据椎动脉移位情况将C3～C6处钩突增生程度分为Ⅲ度,Ⅰ度：椎动脉无移位;Ⅱ度：椎动脉移位距离≤2.5 mm;Ⅲ度：椎动脉移位距离＞2.5 mm.结果：（1）所观察的610处钩突中,因钩突增生对椎动脉造成影响的有68处（11.1％,68/610）,以C6钩突最为多见（48.5％,33/68）,C3钩突最为少见（4.4％,3/68）.上关节突对椎动脉造成影响的共41处（6.7％,41/610）,以C4、C5上关节突多见（92.7％,33/41）,因钩突增生对椎动脉造成影响多于因上关节突增生对椎动脉造成的影响（x2=12,P＜0.01）.（2）除C3之外,C4～C7左右侧L/M值无差别.（3）右侧钩突增生程度为Ⅰ度共140处,L/M值为0.996±0.104;Ⅱ度共13处,L/M值为1.084±0.080;Ⅲ度共11处,L/M值为1.252±0.124.左侧钩突增生程度为Ⅰ度共130处,L/M值为0.980±0.060;Ⅱ度11处,L/M值为1.044±0.056;Ⅲ度15处,L/M值为1.200±0.060,3种程度的增生左右侧钩突个数均无差别.结论：颈部CTA检查可以准确地判定椎动脉与周围骨质结构的关系,钩突增生较关节突增生更易影响椎动脉.L/M的计算可用于判定钩突增生对相邻椎动脉的影响程度.

Influence of uncinate process and superior articular process on vertebral artery in CTA image

Objective： To investigate the relationship between vertebral artery and its adjacent uncinate process as well as superior articular process and to determine the influence of uncinate processes hyperplasia on the vertebral artery. Methods： Sixty one patients were selected who underwent cervical artery CTA, and the CT angiography of the left and right vertebral artery was obtained by the method of muhiplanar reconstruction on the direction of the vertebral artery. The relationship between uncinate process and its adjacent vertebral artery was observed on coronal plane. By the rotation angle of the image on the reorganization, sagittal images of the superior articular process was obtained and the relationship between superior articular process and adjacent vertebral artery was observed. The distance of the uncinate processes protruding to the outmost point of the vertebral artery to the midline of the cervical spine was measured on the coronal plane （L）, and half width of the middle part of vertebral body was measured （M）, on which L/M values was calculated. The C3-C6 uncinate process hyperplasia was divided into three types based on shift distance of the vertebral artery. Type I ：the vertebral artery with no shift; Type Ⅱ ：shift distance of the vertebral artery less than 2.5 mm;Type m ：shift distance of the vertebral artery more than 2.5 mm. Results：（ 1 ） In the observed 610 uncinate processes, the number of influence on the vertebral artery due to uncinate process hyperplasia was 68,most commonly seen in the 6th cervical vertebra while most rarely seen in the 3rd cervical vertebra. The number of influence on the vertebral artery due to superior articular process hyperplasia was 41, most commonly seen in the 4th and 5th cervical vertebxa. Uncinate processes hyperplasia were more likely to influence the vertebral artery than the superior articular processes （X2=12,P〈0.01）. （2）In addition to the third cervical vertebra, C4-C7 left and right sides of L/M values were not significantly different. （3）The number of type I right uncinate processes hyperplasia of C3-C6 was 140 and I/M value was 0.996±0.104; and the number for type Ⅱ was 13 and L/M value was 1.084±0.080; type Ⅲ was 11 with I/M value of 1.252±0.124. The number of type Ⅰ left uncinate processes hyperplasia of C3-C6 was 130 and L/M value was 0.980±0.060 while type Ⅱ was 11 with UM value of 1.044±0.056;type m was 15 and L/M value was 1.200±0.060. The numbers of right and left uncinate processes were not significantly different in the three types of hyperplasia. Conclusion：Cervical artery CTA can precisely determine the relationship between vertebral artery and the surrounding bone structures. And uncinate processes are more likely to influence the vertebral artery than the superior articular processes. Calculated L/M values can determine the degree of influence of uncinate professes on lhe vrrlebral arlery.