What it means
Some CT and MRI scans take pictures at several moments after a contrast injection. Washout describes a lesion that brightens and then fades faster than expected. In the liver, it means the lesion looks darker than the surrounding liver on the later pictures. In the adrenal glands, it is often a percentage, worked out from the nodule's density before contrast, about a minute after, and 15 minutes after.
When it matters
In an adrenal nodule, strong washout supports an adenoma, a very common benign growth, though your doctor may still check hormone levels. In a liver at risk, such as one with cirrhosis, it is read differently. Together with early bright enhancement, it is one of the main signs LI-RADS uses to judge the chance of liver cancer. Further imaging or a specialist review often follows. In breast MRI, a washout pattern also draws a closer look.
Questions to ask your doctor
- Which organ showed washout, and what does it mean there?
- Does the washout point to a harmless growth, or does it need more tests?
- Do I need blood tests or a different scan to confirm what it is?
