【摘要】 目的　探讨多层面螺旋CT图像后处理血液铸型 (fly around)技术诊断脑动脉瘤特别是微小动脉瘤 (瘤体直径≤ 2mm)的临床应用价值。方法　对 10 4例临床怀疑脑动脉瘤病人 (其中蛛网膜下腔出血者 86例 )的多层面螺旋CT三维血管造影 (MS 3D CTA)后处理图像、DSA图像和手术结果进行回顾性对比研究。用多层面螺旋CT扫描仪 Aquilion(Toshiba)采集原始数据。扫描和图像重建的主要技术参数是 :原始数据采集层厚 1 0mm、螺距 3 5、每周扫描时间 0 5s、延迟时间 15～ 2 3s;静脉注射非离子型对比剂 ,剂量 2 0ml/kg ,高压注射器注射 ,流率 3 0～ 5 0ml/s。图像后处理工作站SGI O2 ,软件Alatoview版本 1 4 2 ;三维图像后处理技术采用血液铸型 (fly around)、遮盖容积重建 (SVR)和最大密度投影 (MIP)。后处理图像与DSA图像分别由 3位放射科医生用双盲法进行分析和评价 ,其结果做H检验。10 4例病人中有 6 8例接受DSA检查 ,6 5例经手术治疗。结果　经DSA和手术证实的脑动脉瘤 70个。瘤体最大直径 2 4 0mm ,最小直径 1 0mm ,其中 :大动脉瘤 5个 ,小动脉瘤 4 0个 ,微小动脉瘤 2 5个。fly around检出微小动脉瘤 2 5个 ,SVR和MIP各检出 2 3个 ,DSA检出 2 1个。经确定诊断性试验fly around诊断微小动脉瘤的准确度为 95 71更多还原

【Abstract】 Objective To exploring the clinical value of multislice helical CT fly around as a new method for diagnosing micro intracranial aneurysms(≤2 mm in diameter) Methods In this retrospective study, we compared the usefulness of multislice helical computed tomographic three dimensional angiography (MS 3D CTA ), digital substraction angiography (DSA) and surgery for the detection and assessment of clinical suspected intracranial aneurysms in 104 patients, 86 patients who presented with acute, nontraumatic SAH Row data was acquired by Multislice helical CT Aquilion (Toshiba) The parameters of scanning and images reconstructing were: slice thickness 1 0 mm, helical pitch 3 5, scan speed was 0 5 s per rotation, delay time was 15-23 s; Nonionic contrast medium was injected intravenously (2 0 ml/kg) at speed of 3 0-5 0 ml/s Source images were processed using a workstation SGI O2, images post processing software was Alatoview,ver: 1 42 The reconstructed images were then processed into fly around and shaded volume rendering (SVR) and maximal intensity projection (MIP), and Entire brain DSA was performed Images of MS 3D CTA and DSA were analyzed by 3 radiologists at double blinded Results 70 aneurysms were proved at DSA and surgery, largest aneurysms was 24 0 mm in diameter and smallest aneurysms was 1 0 mm in diameter Five of 70 aneurysms was large aneurysms, 40 was small aneurysms and 25 was micro aneurysms: fly around found out 25 micro aneurysms, SVR and MIP found out 23 of them, DSA found out only 21 of them For detected micro aneurysm, accuracy of fly around was 95 71%, sensitivity was 100.0% and specificity was 93 33%,positive predictive value was 89 29, negative predictive value was 100 0%, accuracy of SVR and MIP was 95 71%, sensitivity was 92 0% and specificity was 97 78%,positive predictive value was 95 83%, negative predictive value was 95 65%, accuracy of DSA was 94 29%, sensitivity was 84 0% and specificity was 100.0%,positive predictive value was 100 0%, negative predictive value was 91 84% Statistic t test values of aneurysms diameter in images of fly around and DSA was 1 52, P >0 05 There was non distinct deference Kruskal Wallis test value for interobserver was 57 04, P <0 01 Conclusion Accuracy and sensitivity and specificity for fly around was higher than SVR and DSA in integrated establish, so fly around is a new and reliable MS 3D CTA method for detecting intracranial aneurysms and micro intracranial aneurysms更多还原