多层CT血管成像与数字减影血管造影诊断颅内微小动脉瘤的比较

目的 探讨MSCTA对最大径≤3 mm颅内微小动脉瘤(IMA)的诊断价值.方法 回顾性分析连续826例可疑颅内动脉瘤患者的临床和影像资料.全部患者住院前(发病后2 h～4 d)均采用16层螺旋CT行MSCTA,全部颅内动脉瘤均经DSA、三维旋转数字减影血管造影(3DRA)或手术证实.MSCTA、DSA及3DRA等影像资料由2名放射科医师独立进行分析.以DSA或3DRA为标准,计算MSCTA诊断IMA的敏感性、特异性及准确度,采用Kappa分析,评价DSA或3DRA与MSCTA两种检查方法诊断颅内IMA的一致性.采用X~2检验分析IMA与非IMA患者多发动脉瘤的患病率.结果 826例可疑颅内动脉瘤患者中,788例为颅内动脉瘤患者,单发706例,多发82例,共发现889个动脉瘤,38例MSCTA、DSA或3DRA检查结果均为阴性.经DSA或3DRA检查证实,212例患者(271个动脉瘤)共有232个IMA.MSCTA检出229个IMA,假阳性1例,漏诊4个.以DSA或3DRA为标准,MSCTA诊断IMA的敏感性、特异性、准确度分别为98.3%(228/232)、97.4%(38/39)、98.2%(266/271).两种检查方法有较强的一致性(Kappa值为0.927,P<0.05).IMA与非IMA患者多发动脉瘤患病率分别为21.2%(45/212)、6.4%(37/576),差异有统计学意义(X~2=36.421,P<0.01).结论 MSCTA诊断IMA具有较高价值,鉴于MSCTA对IMA的检出达到≤3 mm水准,提出将颅内IMA影像大小界定从4～5 mm调整为≤3 mm.

Comparative study between multi-slice CT angiography and digital subtraction angiography in detection of intracranial micro-aneurysms

Objective To investigate the value of multi-slice computed tomography angiography (MSCTA)in the detection of intracranial micro-aneurysms(aneurysm≤3 mm in maximal diameter, IMA).Methods The clinical history and images of 826 patients with suspected intracranial aneurysms were retrospectively analyzed.All patients underwent MSCTA on 16-slice row CT before hospitalization(from 2 h to 4 d after symtom onset).All intracranial aneurysms were confirmed by digital subtraction angiography (DSA), three-dimensional rotational angiography (3DRA) or surgery.Two independent radiologists assessed all the images.The MSCTA findings were compared with the DSA/3DRA results.The sensitivity, specificity, and accuracy of MSCTA for diagnosis of IMA was calculated.The diagnostic consistency between DSA/3 DRA and MSCTA was determined by Kappa statistics.The prevalence of multiple aneurysms between the group of patients with IMA and the group of patients without IMA was evaluated by Chi-square test Results A total of 889 aneurysms in 788 of the 826 patients were detected.Among them, 706 patients had single aneurysm and 82 patients had multiple aneurysms.No aneurysms were detected in 38 patients.Among the 212 patients who underwent DSA/3 DRA, 271 aneurysms were found and 232 were IMA.MSCTAdetected 229 IMA.There was 1 false-positive finding and 4 false-negative findings by MSCTA.The sensitivity, specificity and accuracy of MSCTA for IMA was 98.3% (228/232), 97.4% (38/39), 98.2% (266/271).There was excellent agreement between two techniques (Kappa=0.927, P<0.05).The prevalence of multiple aneurysms was 21.2% (45/212) in the patient group with IMA and 6.4% (37/576) in the group without IMA.There was statistically significant difference between the two groups (X~2=36.421, P<0.01).Conclusions The detection value of IMA by MSCTA was high.The cutoff level of diameter of intracranial IMA should be adjusted from 4-5 mm to ≤3 mm.