CT检出结肠结节状病灶的影响因素  

Factors affecting CT and CTC in detecting colon focus

作　　者：欧阳林[1] 李敏[1] 周水添[1] 林谋固[1] 陈晓武[1] 

机构地区：[1]一七五医院放射科厦门大学医学院附属医院,福建漳州363000

出　　处：《中国临床医学影像杂志》2007年第7期503-505,共3页Journal of China Clinic Medical Imaging

摘　　要：目的:利用仿真模型研究结肠结节状病灶的特征、CT扫描参数、阅片视窗及仿真成像(CTC)对CT检出病灶的影响。材料与方法:利用仿真材料制造30个结节放置到仿真人的结肠内壁上,结节分别为0.5cm隆起形、0.3cm隆起形、0.2cm隆起形、0.2cm扁平形、0.2cm高密度扁平形,每种结节6个。分别应用方案8.0mm/2.5mm/17.5(层厚/准直/螺距)和方案5.0mm/1.0mm/7.0扫描并CTC成像。对横断面扫描图像分别应用3种视窗阅片。检测不同情况下结节的显示情况。结果:窗宽1000HU,窗中心-500HU时,8.0mm/2.5mmm/17.5横断面图像及CTC显示0.5cm、0.3cm所有结节,结节边缘清楚,影像测量值与实物大小相符,而0.2cm结节,横断面图像仅隐约显示1个高密度扁平形结节,CTC图像隐约显示1个高密度扁平形和3个隆起形结节。5.0/1.0/7.0扫描横断面图像及CTC图像除0.2cm低密度扁平形结节未见显示外,其余4种结节均全部显示。窗中心-1000HU时,上述结节边缘模糊,影像测量值略偏大。窗中心0HU时,0.3和0.2cm结节未见显示,0.5cm结节显示暗淡、变小。结论:结肠结节特征、CT扫描参数、阅片视窗及仿真成像均影响CT对结节的检出,CTC对检出小结节的敏感性优于原始横断面扫描图像。Objective： By simulating the characters of colon nodule focus, study the influence of the colon focus characters, CT scan scheme, view window and CT virtual colonscopy （CTC） on CT finding. Materials and Methods： Make 30 nodules by using emulational material, these nodules are made into 5 different types, including 0.Scm size with hunch shape, 0.3cm size with hunch shape, 0.2cm size with hunch shape, 0.2cm size with fiat shape, 0.2cm size with higher density and flat shape, each type includes 6 nodules, then place them at the colon wall. Scan these nodules with different schemes, including 8.0mm/2.5mm/17.5 （slice/collimation/pitch） and 5.0mm/1.0mm/7.0, and reconstruct CTC image. Read these primary scan images with 3 different kinds of view window, then evaluate the display of these nodules. Result： At window wide 1000HU, center level -500HU, primary image and CTC image of scheme 8.0mm/2.5mm/17.5 display all 0.5cm and 0.3cm nodules, with clear brim, and the nodules size accord with their practical size, however, for 0.2cm nodules, the primary image only looms out faintly 1 higher density with fiat shape nodule, CTC only looms out 3 hunch shape nodule, and 1 higher density with fiat shape nodule. Primary image and CTC image of scheme 5.0mm/1.0mm/7.0 display all nodules but nodule of 0.2cm size with lower density with fiat shape. At window center level -1000HU, the brim of these nodules were blurred, with ＂faint margin＂ sign. At window center level 0HU, 0.3cm and 0.2cm nodules were not displayed, 0.Scm nodule displayed dim and smaller. Conclusion： The characters of emulational colon nodule, scan scheme, view window and CTC together influence CT to detect focus, CTC is more sensitive than primary transection image in finding out small focus.

关 键 词：结肠疾病 体层摄影术 X线计算机 

分 类 号：R574.62[医药卫生—消化系统] R814.42[医药卫生—内科学]