Anderson G B, Ashforth R, Steinke D E, Findlay J M
Division of Neurosurgery, University of Alberta, Edmonton, Canada.
AJNR Am J Neuroradiol. 2000 Jun-Jul;21(6):1011-5.
Digital subtraction angiography (DSA) is the standard of reference for detecting cerebral vasospasm after subarachnoid hemorrhage (SAH). CT angiography (CTA) is a relatively recent method for depicting the intracranial arterial vasculature. The purpose of this study was to compare CTA and DSA in the detection and quantification of cerebral vasospasm.
Seventeen patients with SAH underwent initial CTA with or without DSA and follow-up CTA and DSA. The follow-up CTA and DSA studies were performed within 24 hours of each other and 5 to 10 days after SAH. Maximum intensity projection images were produced for each CTA. Six arterial locations were examined for spasm: the suprasellar internal carotid artery (ICA), the M1 and M2 segments of the middle cerebral artery, the A1 and A2 segments of the anterior cerebral artery, and the basilar artery. Vasospasm was categorized as none, mild (<30% luminal reduction), moderate (30% to 50% reduction), or severe (>50% reduction).
The overall correlation between CTA and DSA was 0.757, but was better for proximal than distal locations (0.88-1.00 versus 0.152-0.446). Agreement between CTA and DSA was greater for no spasm (92%) and severe spasm (100%) than for mild (57%) or moderate (64%) spasm. CTA was highly accurate for no spasm or severe spasm in proximal locations (96%, and 100%, respectively); it was less accurate (90% and 95%, respectively) for mild or moderate spasm in these locations. For distal locations, the accuracy for absent, mild, moderate, or severe spasm was 78%, 81%, 94%, and 100%, respectively.
CTA is highly sensitive, specific, and accurate in detecting no spasm or severe cerebral vasospasm in proximal arterial locations; it is less accurate for detecting mild and moderate spasm in distal locations.
数字减影血管造影（DSA）是检测蛛网膜下腔出血（SAH）后脑血管痉挛的参考标准。CT血管造影（CTA）是一种用于描绘颅内动脉血管系统的相对较新的方法。本研究的目的是比较CTA和DSA在检测和量化脑血管痉挛方面的差异。
17例SAH患者接受了初始CTA检查（有或无DSA）以及后续的CTA和DSA检查。后续的CTA和DSA检查在彼此24小时内且在SAH后5至10天进行。为每个CTA生成最大强度投影图像。检查六个动脉部位有无痉挛：鞍上颈内动脉（ICA）、大脑中动脉的M1和M2段、大脑前动脉的A1和A2段以及基底动脉。血管痉挛分为无、轻度（管腔缩小<30%）、中度（缩小30%至50%）或重度（缩小>50%）。
CTA和DSA之间的总体相关性为0.757，但近端部位的相关性优于远端部位（0.88 - 1.00对0.152 - 0.446）。CTA和DSA在无痉挛（92%）和重度痉挛（100%）方面的一致性高于轻度（57%）或中度（64%）痉挛。CTA对近端部位无痉挛或重度痉挛的诊断准确性很高（分别为96%和100%）；对这些部位轻度或中度痉挛的诊断准确性较低（分别为90%和95%）。对于远端部位，无、轻度、中度或重度痉挛的诊断准确性分别为78%、81%、94%和100%。
CTA在检测近端动脉部位无痉挛或重度脑血管痉挛方面具有高度敏感性、特异性和准确性；在检测远端部位轻度和中度痉挛方面准确性较低。
