MRI Evaluation of Rectal Carcinoma
Fig. 14.1 Sagittal T2-weighted sequence shows annular, mid rectal tumor (arrows), which is seen at 8 cm from the anal verge. Sagittal sequences are very useful for assessing the site…
Dual-Energy CT and Its Applications in the Abdomen
Fig. 31.1 Schematic of relationship of attenuation of iodine (y-axis) to photon energy (x-axis). Note peak in attenuation that occurs at 33.2 keV, the k-edge of iodine. The k-edge of…
The Appendix
Algorithm 13.1 Algorithmic approach for evaluation of the appendix Normal Appendix A useful landmark for identifying the appendix at CT is the fatty ileocecal valve (Fig. 13.1). When trying to identify…
Cirrhosis and Hepatocellular Carcinoma
Causes of cirrhosis Hepatitis C (55 %) Hepatitis B (16 %) Alcohol (13 %) Cryptogenic nonalcoholic fatty liver disease and nonalcoholic steatohepatitis (16 %) Other causes: hereditary hemochromatosis, constrictive pericarditis,…
Overview of CT Colonography
Algorithm 11.1 Risk of Adenoma to Carcinoma” [3–7] Hence, the success of any diagnostic test as a colorectal cancer screening tool lies in its ability to accurately diagnose polyps measuring 1…
Post-locoregional Therapy Imaging of the Liver
Fig. 4.1 A 64-year-old male with unresectable HCC. The segment II lesion (arrow) demonstrates hyperenhancement on the contrast-enhanced gradient echo MRI images before treatment (a). Immediately after administration of radioembolization…
Overview of CT and MRI Techniques of the Liver
Fig. 1.1 Axial non-contrast CT image shows that the liver measures 10 HU less than the spleen secondary to fatty infiltration The abnormal hepatic accumulation of copper, glycogen, or iron…
Radioactive Decay and Interaction of Radiation with Matter
(1) Cleveland Clinic, Emeritus Staff, Cleveland, OH, USA KeywordsAtomic structureNuclear structureRadioactive decayDecay equation γ Ray interactionAttenuation Atomic Structure Matter is composed of atoms. An atom consists of a nucleus…
Data Acquisition and Corrections
(1) Cleveland Clinic, Emeritus Staff, Cleveland, OH, USA KeywordsPET dataSinogramPET/CTPET/MRAttenuation correctionTime of flightArtifacts PET Data Acquisition Positron emission tomography (PET) is based on the detection in coincidence of the…
Performance Characteristics of PET Scanners
(1) Cleveland Clinic, Emeritus Staff, Cleveland, OH, USA KeywordsSpatial resolutionSensitivityRandom countsScatter fractionQuality controlAcceptance testing Introduction In PET/CT and PET/MR imaging, PET images are of primary interest, whereas CT and…
