低辐射剂量脑CTA的应用价值  

Application of Low-dose CTA of Head

作　　者：吕秀华[1] 麻增林[2] 贺丽英[1] 闫玉昌[1] 

机构地区：[1]北京朝阳医院京西院区放射科,北京100043 [2]北京中医药大学东直门医院放射科,北京100700

出　　处：《中国医学影像学杂志》2010年第4期364-367,共4页Chinese Journal of Medical Imaging

摘　　要：目的:对比分析低辐射剂量和常规剂量脑CTA对脑动脉血管的显示效果并进一步探讨低辐射剂量脑CTA的临床应用价值。材料和方法:将80例患者随机分成两组,分别行低剂量与常规剂量脑CTA检查,对横轴图像、容积显示(VR)和最大密度投影(MIP)图像进行观察和对比分析,主要评价CTA图像中脑动脉血管的显影强度、图像噪声以及脑动脉血管结构的显示效果。结果:低剂量组CTA平均辐射剂量(18.58mGy)比常规剂量组(37.17mGy)降低50%,低剂量组CTA脑动脉血管的显影强度与常规剂量组相比无显著性差异(P=0.296),其噪声略大于常规剂量组,但无显著性差异(P=0.235)。两组间VR和MIP图像中的脑动脉结构的显示效果无显著性差异(P=0.128)。结论:同常规剂量CTA相比,低剂量CTA的显影强度、脑动脉结构的显示效果与常规剂量组无明显差异,较大地降低了辐射剂量,具有较好的应用前景。Purpose To compare and analyse the display effect of cerebral arteries by Low --dose and Routine-dose CT angiography（CTA ） and to explore the clinical application of low-dose CTA of brain. Materials and Methods 80 patients were divided into 2 Groups randomly. Low-dose（n = 40） and Routine-dose（ n = 40） CTA was performed respectively. The CTA images including 2D Axial.3D VR and MIP images were compared and analysed by two observers blinded to the symptoms of patients. They were mainly asked to assess the display effect of cerebral arteries on CTA images including enhancement strength, image noise, and structure display. Results Mean radiation dose of the patients was significantly reduced from 37.17 mGy in Routine-dose group to 18.58 mGy in Low-dose group （50%）, but no significant difference was found of enhancement strength of cerebral arteries（P=0. 296）and image noise（P=0. 235）. Structure display of cerebral arteries on VR and MIP images was no significant different （P=0. 128） between groups. Conclusions Mean radiation dose of Low-dose cerebral CT angiography was significantly reduced compared with routine-dose scan, but the image quality of CTA in Low-dose group could reach the standard of imaging diagnosis. Thus, the Low-dose cerebral CT angiography is of great value in future clinic application.

关 键 词：体层摄影术 X线计算机 脑血管造影术 辐射剂量 

分 类 号：R743.045.4[医药卫生—神经病学与精神病学]