Purpose: The presence of contrast materials on computed tomography (CT) images can cause problems in the attenuation correction of positron emission tomography (PET) images. These are because of errors converting the CT attenuation of contrast to 511-keV attenuation and by the change in tissue enhancement over the duration of the PET emission scan. Newer CT-based attenuation correction (CTAC) algorithms have been developed to reduce these errors.
View Article and Find Full Text PDFGallium-67 citrate and radiolabeled white blood cells have become standard inflammation/infection-seeking agents whereas other agents, such as (99m)Tc diphosphonates, commonly are used to infer an infectious process. These radiopharmaceuticals reflect physiologic and pathologic function rather than anatomical abnormality. In the clinical setting, it is often necessary to correlate these functional studies with anatomical imaging.
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