<prompt> True about Hybrid PETCT scans:Functional-anatomical mappingProvide images that help to pinpoint the abnormal metabolic activity to respective anatomical structuresCan differentiate benign from malignant lesions as small as 1 cm.All of the above  <response>: Hybrid imaging allows the superimposition of PET and CT images, a technique known as functional-anatomical mapping. Hybrid PETCT scans provide images that help pinpoint the abnormal metabolic activity to anatomical structures seen on CT and provide more accurate diagnoses than the two scans performed separately. FDG-PET : It can differentiate benign from malignant lesions as small as 1 cm. However, false-negative findings can occur in lesions with low metabolic activity such as carcinoid tumors and bronchioloalveolar cell carcinomas, or in lesions 1 cm in which the required threshold of metabolically active malignant cells is not present for PET diagnosis. False-positive results can be seen due to FDG uptake in inflammatory conditions such as pneumonia and granulomatous diseases. Areas of normal physiological uptake in PET CT:- - Brown fat - Thymus - Brain tissue - Myocardium - GI Tract 