Test-bolus、K空间中心填充法及并行采集技术在颈部动脉3DCEMRA中的应用  

The Application of Test-bolus,Central K space and Parallel Imaging in 3DCEMRA of Neck Arteries

作　　者：毕永民[1] 张挽时[1] 方红[1] 宋云龙[1] 樊红霞[1] 王东[1] 祝红线[1] 

机构地区：[1]中国人民解放军空军总医院磁共振科,北京100142

出　　处：《临床放射学杂志》2010年第11期1539-1543,共5页Journal of Clinical Radiology

摘　　要：目的 探讨Test-bolus法、K空间中心填充法及并行采集技术在颈部动脉三维对比增强磁共振血管成像（3DCEMRA）中的应用。资料与方法对87例可疑颈部动脉病变的患者行3DCEMRA,步骤为：（1）确定扫描延迟时间：用Test-bolus法测量对比剂到达主动脉弓的峰值时间,扫描数据采用K空间中心填充法,得到扫描延迟时间=峰值时间。（2）用GRAPPA并行采集技术缩短扫描时间。（3）3DCEMRA扫描。（4）对图像用最大信号强度投影（MIP）法三维重组,将图像质量分为3个等级,Ⅰ级为动脉信号均匀,显影清晰,静脉几乎不显影;Ⅱ级为动脉信号均匀,显影清晰,静脉轻度显影（信号强度小于动脉信号）;Ⅲ级为动脉信号不均匀,静脉明显显影（信号强度等于或高于动脉信号）。评价图像质量及病变显示情况。结果 以2ml/s的流率注射对比剂,到达主动脉弓的峰值时间为11~28s,平均为19s。87例患者颈动脉图像质量分级：Ⅰ级者82例（94.25%）,Ⅱ级者5例（5.75%）,Ⅲ级者0例。87例患者中15例（17.24%）显示颈部动脉无异常。72例（82.76%）共186个血管段有病变,其中动脉轻度狭窄占26.88%（50/186）,中度狭窄占23.12%（43/186）,重度狭窄占41.94%（78/186）,椎动脉迂曲占1.61%（3/186）。结论 利用Test-bolus技术、K空间中心填充法确定最佳扫描延迟时间,用并行采集技术缩短扫描时间,能获得高浓度、高分辨率、大范围的高质量颈动脉图像,对颈动脉疾病的诊断和治疗有重要意义。Objective To assess the The application of Test bolus,central K-space and parallel imaging in 3DCEMRA of neck arteries.Materials and Methods Eighty-seven patients suspected with neck artery diseases performed 3DCEMRA examination.The steps as follows：（1）confirming the optimal time to delay（Td）：measuring the time to peak（Tp）of contrast medium arrival to aortic arch with Test bolus（injection rate 2ml/s,dose 2ml）,data centrally filled in K-space,so we got Td=Tp.（2）using parallel imaging（GRAPPA）with acceleration factor of 2 to reduce the scan time.（3）3DCEMRA scanning.（4）reconstruction of the images with MIP,the quality of the images were divided into 3 degrees-degree I：excellent arterial signal intensity without venous signal intensity;degree II：good arterial signal intensity（venous signal intensity lower than arterial signal intensity）;degree III：poor arterial signal intensity（venous signal intensity equal to or greater than arterial signal intensity）.The quality of images and the diseases of arteries were analysed.Results Peak time of contrast medium to aortic arch is 11-28s,average 19s.Of all the 87 patients,percentage of degree I,II and III of the images were 94.25%,5.75% and 0%,respectively.As the arteries,72 patients with 186 segmental arteries were abnormal,including mild stenosis 26.88%,moderate stenosis 23.12%,severe stenosis 41.94%,and tortuous arteries 1.61%,respectively.Conclusion Using Test bolus and data centrally K-space filling to confirm the optimal delay scan time,and parallel imaging method to reduce scan time,the highest signal intensity,high spatial resolution,and large volume coverage arterial images can be obtained,which are very useful for clinical diagnosis and therapy.

关 键 词：磁共振血管造影术 颈动脉 椎动脉 对比剂 

分 类 号：R445.2[医药卫生—影像医学与核医学]