Our Adrenal Washout Calculator helps clinicians assess adrenal masses using CT Hounsfield Units (HU). Easily calculate both Relative Washout Percentage (RW%) and Absolute Washout Percentage (AW%) to aid in differentiating benign adrenal adenomas from other potentially malignant or indeterminate lesions, supporting accurate diagnostic decisions based on imaging.
Formula:
The Adrenal Washout Calculator utilizes Hounsfield Unit (HU) values from unenhanced, enhanced, and delayed CT images to determine two key percentages:
- Absolute Washout Percentage (AW%):
AW% = ((HUenhanced - HUdelayed) / (HUenhanced - HUunenhanced)) * 100% - Relative Washout Percentage (RW%):
RW% = ((HUenhanced - HUdelayed) / HUenhanced) * 100%
Where:
- HUunenhanced = Hounsfield Units on unenhanced CT imaging
- HUenhanced = Hounsfield Units on post-contrast CT imaging (e.g., 60-second delay)
- HUdelayed = Hounsfield Units on delayed post-contrast CT imaging (e.g., 15-minute delay)