Jha Ashish Kumar, Purandare Nilendu C, Shah Sneha, Agrawal Archi, Puranik Ameya D, Rangarajan Venkatesh
Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Parel, Mumbai, Maharashtra, India.
Indian J Nucl Med. 2013 Oct;28(4):232-3. doi: 10.4103/0972-3919.121970.
Artifacts present in computed tomography (CT) image often degrade the image quality and ultimately, the diagnostic outcome. Ring artifact in trans-axial image is caused by either miscalibrated or defective detector element of detector row, which is often categorized as scanner based artifact. A ring artifact detected on trans-axial CT image of positron emission tomography/computed tomography (PET/CT), was caused by contamination of CT tube aperture by droplet of injectable contrast medium. This artifact was corrected by removal of contrast droplet from CT tube aperture. The ring artifact is a very common artifact, commonly cited in the literature. Our case puts forward an uncommon cause of this artifact and its method of correction, which also, has no mention in the existing literature.
计算机断层扫描（CT）图像中出现的伪影常常会降低图像质量，最终影响诊断结果。横轴位图像中的环形伪影是由探测器排中校准错误或有缺陷的探测器元件引起的，通常被归类为基于扫描仪的伪影。在正电子发射断层扫描/计算机断层扫描（PET/CT）的横轴位CT图像上检测到的环形伪影，是由可注射造影剂的液滴污染CT管孔径所致。通过从CT管孔径中去除造影剂液滴对该伪影进行了校正。环形伪影是一种非常常见的伪影，文献中经常提到。我们的病例提出了这种伪影的一个不常见原因及其校正方法，现有文献中也未提及。
