双能CT血管成像对颈内动脉狭窄及闭塞的诊断  

Dual-energy CT Angiography for Evaluation of Internal Carotid Artery Stenosis and Occlusion

作　　者：陈钰[1] 薛华丹[1] 金征宇[1] 刘炜[1] 孙昊[1] 王萱[1] 赵文敏[1] 王沄[1] 牟文斌[1] 

机构地区：[1]中国医学科学院北京协和医学院北京协和医院放射科,北京100730

出　　处：《中国医学科学院学报》2009年第2期215-220,共6页Acta Academiae Medicinae Sinicae

摘　　要：目的将双能CT血管成像(CTA)与时间飞跃法磁共振血管成像(TOFMRA)进行比较,评价双能CTA去除颈内动脉骨骼、钙化斑块的能力。方法对32例怀疑头颈部动脉粥样硬化的患者进行双源双能CTA及TOFMRA扫描。在CTA检查前或后1d～1月内行MRA检查。依据Fischer(1938)分段法将颈内动脉颅内段分为5段。采用4分评分系统评价双能头颈部CTA图像质量,评分≥3的血管为可以进行诊断的血管。血管节段狭窄程度分为轻度狭窄(0～29%)、中度狭窄(30%～69%)、重度狭窄(70%～99%)和完全闭塞(100%)。比较双能CTA与TOFMRA对颈内动脉狭窄程度诊断的一致性。结果99%动脉节段的评分≥3分。双能CTA与MRA诊断狭窄程度分级一致的血管占98%。对于轻度狭窄与闭塞的血管,双能CTA与MRA诊断的一致性达100%。对中、重度狭窄的血管节段,双能CTA显示7段血管的狭窄程度大于MRA,Wilcoxon检验显示两者诊断的差异具有显著性(Z=-3.071,P=0.002)。结论双源双能CTA扫描能去除骨骼与钙化对图像的影响,是评估颈内动脉颅内狭窄的有效方法。在诊断血管重度狭窄时,相对于MRA存在过评估。Objective To compare the feasibility of bone and calcified plaque subtracted dual-energy CT angiography （CTA） with time of flight magnetic resonance angiography （ TOF MRA） in evaluation of internal carotid artery atherosclerosis. Methods Totally 32 patients received a dual-energy CTA scan, along with a cerebral TOF MRA scan before or after CTA examination from one day to one month. Dual-energy software was used for bone and calcified plaque subtraction. Five anatomical segments were described for each internal carotid artery according to Fischer （1938）. Ratings were based on a 1-4 scale for the dual-energy CTA maximum intensity projection （MIP） image ： 1 not diagnostic, 2 partially diagnostic, 3 diagnostic, and 4 excellent. Lesions were categorized as mild （0-29%）, moderate （ 30% -69% ）, severe （70% -99 % ）, or occluded （ no flow detected）. Ste- nosis of internal carotid artery was evaluated based on post-subtracted CTA images and TOF MRA images. Results In 320 arterial segments, 99% of arterial segments were ≥ 3 score. Grading of stenosis on dual-energy CTA agreed with grading of stenoses on MRA images in 98% of arteries. In the mild and occlusion group, the agreement was 100% respectively. In the moderate and severe group, dual-energy CTA showed more severe stenosis than MRA in 7 vessels and there was significant difference between the results from the two different modalities （Z = -3.071, P = 0. 002）. Conclusion Dual-energy CTA can be used to assess the stenosis of internal arteries around skull base, but may exaggerate the severe stenosis of cerebral arteries compared with TOF MRA.

关 键 词：颈内动脉 双能CT 磁共振血管成像 图像质量 

分 类 号：R814.42[医药卫生—影像医学与核医学] R816.1[医药卫生—放射医学]