比较阈值调节测量法与常规测量法对评价大脑中动脉狭窄的价值

Comparison on value of threshold adjustment and conventional measurement on middle cerebral artery stenosis

目的探讨阈值调节测量法和常规测量法对容积CT数字减影血管造影(VCTDSA)大脑中动脉狭窄程度评价的准确性。方法用常规测量法和阈值调节测量法对80例大脑中动脉狭窄患者进行分析,评估观察者内及观察者间重复性及一致性,用两种方法测量狭窄处及正常血管管径大小,计算各狭窄处的狭窄率,判定狭窄程度。结果观察者内及观察者间两种方法对狭窄部位判定有良好一致性(K=0.99、0.99),观察者内阈值调节测量和常规测量狭窄程度一致性强(K=0.92、0.89),观察者间阈值调节测量和常规测量狭窄程度一致性强(K=0.98、0.87)。阈值调节测量比常规测量多检出轻中度血管狭窄共9处,分别是M1段轻度狭窄2处,M1段中度狭窄1处,M2段轻度狭窄5处,M2段中度狭窄1处;阈值调节测量优于常规测量(-R阈>-R常),两种测量法对血管狭窄程度的判断差异具有统计学意义(P<0.01)。结论 CT血管造影(CTA)测量在观察者内及观察者间具有良好的一致性,阈值调节测量法可减少轻中度狭窄漏诊率,较常规测量更准确反映血管狭窄,为临床介入治疗提供可靠的血管狭窄影像依据。

Objective To assess the accuracy of middle cerebral artery stenosis with threshold adjustment and conventional measurement using volume CT digital subtraction angiography（VCTDSA）.Methods Eighty patients with middle cerebral artery（MCA）stenosis were analyzed with threshold adjustment and conventional measurement.The consistency through the intra-observer and inter-observer were assessed.Diameters of the stenosis vessels as well as the normal vessels were measured,the rate and degree of stenosis were calculated.Results Intra-observer and inter-observer consistency were good to determinate the narrow area（K=0.99,0.99）,threshold adjustment measurement and conventional measurement methods on the degree of stenosis was highly consistent（intra-observer,K=0.92,0.89,inter-observer,K=0.98,0.87）.The detection of mild to moderate stenosis with threshold adjustment measurement were more than that with conventional measurement,including 2 mild and 1 moderate stenosis on M1 segment,5 mild stenosis and 1 moderate stenosis on M2 segment.Threshold adjustment measurement was superior to conventional measurement（P0.01）.Conclusion The two measurements have good the intra-observer and inter-observer consistency.Threshold adjustment measurement can reduce the rate of missed diagnosis of mild to moderate artery stenosis,reflect the degree of stenosis more accurately,and provide reliable information for clinical intervention.