• pathologically proven left adrenocortical adenoma, presented as a functioning adenoma with the manifestation of Cushing disease.
• CT protocol in such cases is CT washout which has two types; absolute and relative. The absolute one can only be calculated when you have a non-contrast phase where CT washout = (Enhanced CT - Delayed CT) / (Enhanced CT - unenhanced CT) x 100%.
• relative washout (non-contrast is not done) = (Enhanced CT - Delayed CT) / (Enhanced CT) x 100%.
• the enhanced phase is acquired at 60 sec while the delayed phase is at 15 minutes.
• to diagnose adrenal adenoma according to the above mentioned CT washout rate, we need:
  • >60% absolute washout
  • >40% relative washout
• in our case, the absolute washout was 76%, diagnostic of adrenal adenoma.
• the essential step in obtaining accurate CT washout after adjusting the CT phases is to fix the level and size of ROI (region of interest). To fix the level of measurement, scanning should start from the same level in all phases in order to obtain measurements in the same numbered slice, otherwise, you should adjust the level manually considering the respiratory movement of abdominal organs. The other point is to fix the size of ROI by propagating or duplicating it in the other phases. 
• the made fatty infiltration of the liver is attributed to manifestations of Cushing disease.

Thanks to Dr. Mostafa Ahmed Sayed Hamada