Willis环磁共振血管成像与血管造影对比研究

目的：对比分析Ｗｉｌｌｉｓ动脉环的ＭＲＡ和ＣＡ表现，探讨ＴＯＦ法ＭＲＡ评价Ｗｉｌｌｉｓ环解剖与功能的价值。材料与方法：选择４３例颅脑血管和肿瘤疾病的ＴＯＦ法ＭＲＡ和ＣＡ资料。ＭＲＡ应用１．０Ｔ超导ＭＲ系统的３Ｄ或２ＤＦＩＳＰ序列扫描，原始血管图像用ＭＩＰ重建。ＣＡ西门子１２５０ｍＡＤＳＡ系统和岛津１０００ｍＡ造影造系统，采用Ｓｅｌｄｉｎｇｅｒ技术导管法股脑血管造（至秒摄取双侧颈动脉和一侧椎动脉造有

Evaluation of Willis' Circle: A Comparison of MRA and Conventional Angiography

Objective:To evaluate TOF MRA in assessing the anatomy and functions of Willis' circle by comparing with conventional angiography (CA). Materials and Methods: Cerebral MRA and CA were performed in 43 patients with cerebral vascular or tumorous diseases. MRA was conducted with a 1.0T MR unit (Magnetom Impact, Siemenz) using 3D (n=41) or 2D (n=2) FISP sequences and MIP post processing algorithm. With Seldinger technique, CA was done on a Siemenz 1 250mA DSA unit (n=36) or on a Shimadzu 1 000mA angiography system (n=7), carotid arteries and at least unilateral vertebral artery were serially filmed. Two experienced radiologists viewed MRA and CA pictures independently, assessing the patency and collateral flow of Willis' circle, also consulted with another radiologist when they had different opinions.Results:MRA accurately demonstrated the collateral flow of Willis' circle. Compared to CA, the sensitivity of MRA was 100%, 97.7%, 100%, 100% and 100% for ICA, ACA, MCA, BA and PCA, respectively, with a specificity of 100%. The sensitivity for AcomA and PcomA was 97.6% and 64.1%, respectively, while the specificity was 50% and 62.5%, respectively. Four false positive and 29 false negative were encountered in this study.Conclusion: TOF MRA is a reliable and non invasive method for assessing the patency and collateral flow of Willis' circle.