正常国人Willis环形态的MRA研究

MRA Study of the Morphology of Willis' Circle in Healthy Chinese

目的 联合运用多种MRA序列和 /或 3DFSPGR序列观察正常国人的Willis环形态及其类型。资料与方法 行MRA检查的正常国人 16 7例。图像分析采用联合分析方法 ,根据Willis环完整情况将Willis环形态分为Ⅰ型 (Willis环完整 )、Ⅱ型 (Willis环前循环完整后循环不完整 )、Ⅲ型 (Willis环前循环不完整后循环完整 )、Ⅳ型 (Willis环前、后循环均不完整 ) ,然后根据组成血管发育情况 ,各类型又分成典型型、变异型、发育不良型和混合型 4种亚型。结果 16 7例正常国人中 ,Ⅰ型占 44 .31%(74/16 7) ,Ⅱ型占 41.92 %(70 /16 7) ,Ⅲ型占 6 .5 9%(11/16 7) ,Ⅳ型占7.19%(12 /16 7)。后交通动脉显示率为 6 4.97%(2 17/334 ) ,前交通动脉显示率为 87.43%(146 /16 7) ,A1段发育不良者占 5 .6 9%(19/334 ) ,未显示者占 1.80 %(6 /334 )。P1段发育不良者占 12 .87%(43/334 ) ,未显示者占 1.2 0 %(4/334 )。结论 利用MRA对正常国人Willis环形态进行分型 ,可为今后有关研究提供依据。

Objective To observe the morphology and patterns of Willis' circle in healthy Chinese by using multiple MRA sequences and/or 3D FSPGR.Materials and Methods MRA and/or 3D FSPGR was performed in 167 healthy Chinese. According to its integrity, Willis' circle was divided into four types. (1) Type Ⅰ, showing an intact circle. (2) Type Ⅱ, having a complete anterior circulation but an incomplete posterior circulation. (3) Type Ⅲ, having an incomplete anterior circulation with a complete posterior circulation. (4) Type Ⅳ, both anterior and posterior circulation being incomplete. Based on the development of the components of the circle, each type was subdivided into four subtypes: typical, variation, hypoplastic and mixed. Results Of 167 cases, type Ⅰ, Ⅱ, Ⅲ and Ⅳ was found in 74 (44.31%), 70 (41.92%), 11 (6.59%) and 12 (7.19%), respectively. The displaying rate of the posterior and the anterior communicating arteries was 64.97% (217/334) and 87.43% (146/167), respectively. Hypoplastic A 1 segment and unrevealed A 1 segment of the anterior cerebral artery were respectively found in 5.69% (19/334) and 1.80% (6/334). Hypoplastic P 1 segment and unrevealed P 1 segment of the posterior cerebral artery were respectively found in 12.87% (43/334) and 1.20% (4/334).Conclusion To classify the patterns of Willis' circle of normal Chinese with MRA can provide useful information for the related studies.