Chemical Shift Mr Imaging Non Enhanced And Washout Contrast Enhanced Ct In Characterization Of Adrenal Masses

The definitive diagnosis of adenomas can be made by; non enhanced CT with attenuation value of less than 10 HU. And in contrast enhanced washout CT: a washout of at least 60% or greater. In quantitative chemical shift MRI using a threshold of more than 20% signal intensity DROP between in phase and opposed phase, and signal intensity index of equal or more than 5%, accurately characterized adenomas. Chemical-shift MR images are justified as the primary technique to distinguish benign from malignant adrenal lesions based on intra cytoplasmic lipid. An adrenal adenoma without abundant intra cytoplasmic lipid may cause the non shifting MR images. At present, chemical-shift MR imaging is still limited for a small number of patients with atypical adrenal tumors. A combination of other techniques, such as dynamic perfusion studies of MR images, seems necessary to improve the predicting accuracy in differentiating unusual adrenal tumors.