Influence of image acquisition parameters on CT artifacts and polyp depiction in spiral CT colonography: in vitro evaluation.
Influence of image acquisition parameters on CT artifacts and polyp depiction in spiral CT colonography: in vitro evaluation.
复制标题
螺旋 CT 结肠成像中图像采集参数对 CT 伪影和息肉描绘的影响：体外评估。
DOI：
10.1148/radiology.217.1.r00oc13165
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发表时间：
2000
期刊：
影响因子：
19.7
通讯作者：
Brink,JA
中科院分区：
文献类型：
--
作者：
Whiting,BR;McFarland,EG;Brink,JA
目的：量化螺旋计算机断层扫描 (CT) 采集参数对三维 (3D) 波纹伪影和息肉描绘的影响。 材料和方法：用充气丙烯酸圆柱体构建体外结肠模型，其中包含 3-13 毫米的合成息肉。将模型浸没在液体中并相对于 z 轴以四个倾斜角度放置。图像数据是在准直度和间距组合分别为 3 毫米和 1.67 以及 5 毫米和 1.6 时采集的。通过测量面内模型边缘宽度的纵向变化来量化波纹伪影，并定性评估这些伪影对有蒂和无蒂息肉描绘的影响。 结果：波纹伪影的平面内大小是相对于纵轴的倾斜角和工作台增量的函数。伪影的平面周期性等于工作台增量的二分之一。结论：工作台增量和物体表面相对于 z 轴的倾斜角度决定了 3D 螺旋 CT 结肠成像中波纹伪影的周期性和大小。尽管对小带蒂息肉的描绘并未受到影响，但一些无蒂息肉因伪影而退化。
PURPOSE:To quantify the effects of spiral computed tomographic (CT) acquisition parameters on the magnitude of three-dimensional (3D) rippling artifacts and polyp depiction.MATERIALS AND METHODS:An in vitro colon phantom was constructed with air-filled acrylic cylinders that contained synthetic polyps of 3–13 mm. The phantom was submerged in fluid and positioned at four angles of inclination relative to the z axis. Image data were acquired at collimation and pitch combinations of 3 mm and 1.67 and 5 mm and 1.6, respectively. Rippling artifacts were quantified by measuring the longitudinal variation of in-plane phantom edge width, and the influence of these artifacts on the depiction of pedunculated and sessile polyps was assessed qualitatively.RESULTS:The in-plane magnitude of the rippling artifact was a function of the angle of inclination relative to the longitudinal axis and the table increment. The through-plane periodicity of the artifact was equal to one-half the table increment.CONCLUSION:The table increment and angle of inclination of the surface of the object relative to the z axis determine the periodicity and magnitude of the rippling artifact at 3D spiral CT colonography. Although the depiction of small pedunculated polyps was not compromised, some sessile polyps were degraded by the artifact.