断层摄影 duàncéngshèyǐng computed tomography Origin Definitions Defs Strokes Stroke Words Sentences Sents 正电子照射断层摄影 zhèngdiànzǐzhàoshèduàncéngshèyǐng positron emission tomography type of medical imaging (PET) that uses radioactive substances to visualize the metabolic activity of tissues and organs