Gas bubble motion artifact in MDCT
Gas bubble motion artifact in MDCT
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DOI：
10.2214/ajr.07.2702
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发表时间：
2008-02-01
影响因子：
5
通讯作者：
Kinahan, Paul E.
中科院分区：
文献类型：
--
作者：
Liu, Franklin;Cuevas, Carlos;Kinahan, Paul E.
OBJECTIVE.我们研究的目的是描述由气泡运动引起的MDCT伪影的成像特征。在2002-2006年期间，10名患者的CT图像显示了被认为是由于CT采集期间气泡移动引起的曲线伪影，由主治身体放射科医生进行了回顾性识别和审查。在MDCT扫描仪上获得临床图像。设计、构建含有水和移动气泡（气体注入速率为0.1和0.5 mL/s）的体模，并使用16-MDCT扫描仪进行扫描。计算机模拟被用来测试我们的假设，这些观察到的文物起源于移动的气体气泡。10例CT均表现为半圆管状伪影，密度接近空气。从体模和计算机模拟获得的MDCT图像显示管状空气衰减半圆形伪影，与10例临床病例的成像结果密切匹配。气泡注入速率的增加使伪影倍增。基于计算机模拟，伪影的精确外观取决于气泡相对于CT扫描仪旋转的位置和速度。气泡运动在CT产生一个半圆形的空气衰减伪影，还没有以前描述我们的知识。伪影通常出现在肠和其他含液体的结构中，其中在CT期间气泡通过液体介质漂浮。
OBJECTIVE. The purpose of our study was to characterize the imaging features of an MDCT artifact caused by gas bubble motion.MATERIALS AND METHODS. For the period 2002-2006, the CT images of 10 patients that revealed a curvilinear artifact thought to be due to a gas bubble moving during CT acquisition were retrospectively identified and reviewed by an attending body radiologist. The clinical images were acquired on MDCT scanners. A phantom containing water and moving air bubbles (gas injection rates of 0.1 and 0.5 mL/s) was designed, built, and scanned using a 16-MDCT scanner. Computer simulation was used to test our hypothesis that these observed artifacts originated from moving gas bubbles.RESULTS. Semicircular tubular CT artifacts with attenuation close to that of air were observed in all 10 clinical cases. The acquired MDCT images from the phantom and the computer simulations showed tubular air-attenuation semicircular artifacts that closely matched the imaging findings on the 10 clinical cases. Increased rates of bubble injection multiplied the artifact. Based on the computer simulation, the precise appearance of the artifact depends on the bubble location and velocity relative to the rotation of the CT scanner.CONCLUSION. Gas bubble motion during CT generates a semicircular air-attenuation artifact that has not been previously described to our knowledge. The artifact is typically found in bowel and other liquid-containing structures in which a bubble of gas floats up through a liquid medium during CT.