The role of MDCT and PET/CT in evaluation of adrenal masses

Abstract

Non invasive imaging can be useful in overcoming the challenges of detecting and characterizing adrenal masses. Multi detector computed tomography represents an extremely sensitive imaging tool and used as primary modality as well for recognizing adrenal expansive lesions, being able to detect lesions of a few millimeters in diameter. The intra lesional washout is a very accurate parameter for differential diagnosis between adenomas and non-adenomas and is essential in the characterization of adenomas without intra cytoplasmic lipids. Most imaging techniques were developed to differentiate adenoma from metastases, with CT washout technique as the most sensitive and specific imaging technique. Using CT attenuation value <10 HU on non-contrast series indicates a lipid-rich adenoma, and no further workup is needed, if the attenuation value is >10 HU on non-contrast series so it is indeterminate, and one should proceed with the washout technique. Absolute washout