摘要
目的 系统分析主要扫描参数对CT仿真内窥镜 (CTVE)图像质量的影响 ,寻找可获得较好图像质量的扫描参数组合。评价CTVE对不同大小、形态的模拟病变的分辨能力 ,进一步确定图像的真实性。方法 应用不同扫描参数分别对不同组别模拟病变的模型进行扫描 ,观察图像质量及模拟病变的分辨情况。结果 准直器宽度、螺距、重叠重建率及重建方式的变化均会不同程度地影响CTVE图像质量。在准直器宽度≤ 3mm、螺距 1.0～ 2 .0、重叠重建率 6 0 %、标准 (STD)重建方式的参数范围内可获得较满意的图像质量 ,并具有可分辨微小结构及较真实显示结构形态的能力。结论 适当选择扫描参数、有效分辨伪影及变形 ,CTVE技术将成为显示空腔脏器病变及结构的有效方法之一。
Objective To analyze systematically the influence of different scan parameters on CT virtual endoscopy (CTVE) and to explore the optimal scan parameters. Additionally, we evaluated the ability of CTVE in detecting the simulated lesions and discuss the accuracy of the image. Methods The artificial phantom was created by 5 groups of simulated lesions with different size and shape. The special shape of simulated lesion (group 1) was scanned by SCT at different parameters (collimation 1-10 mm, pitch 0.5-3.0, overlapping 0-90%, and reconstruction mode soft lung) to determine the optimal scanning parameters. Subsequently, simulated lesions of different sizes and shapes (group 2-5) were scanned using the optimized parameters. Results The image quality of the virtual endoscopy depends on different scan parameters (collimation, pitch, overlapping, and reconstruction mode). The optimal scanning parameters of the artificial phantom were: collimation≤3 mm, pitch 1.0-2.0, overlapping 60%, and a reconstruction mode of STD. CTVE was feasible for ordinary simulated lesions(height, depth≥1 mm) detection≥3 mm in diameter and flat lesions(height, depth=0.5 mm) detection ≥4 mm in diameter. It delineated the shape of the lesions precisely. Conclusion With proper selection of scan parameters, CTVE could be a useful tool in the visualization of the anatomical structures and detection of luminal lesions of hollow organs.
出处
《中华放射学杂志》
CAS
CSCD
北大核心
2000年第8期563-567,共5页
Chinese Journal of Radiology
关键词
CT仿真内窥镜技术
评价研究
模拟病变
分辨能力
Tomography, X ray computed
Image processing, computer assisted
Evaluation studies
