Diffusion-weighted imaging
Read Your Scan Editorial Team·Last updated
Written from published radiology references and reviewed for plain language. Not written or signed by a physician, and not a diagnosis. How we write these pages →
In plain language
An MRI sequence that measures how freely water molecules drift through tissue. Where that drift is blocked, the sequence lights up — which is why it is the fastest way to see a stroke and a standard part of many cancer protocols.
Where you’ll see this
The technique section of brain, abdominal and whole-body MRI reports.
Your report may word it “DWI” or “Diffusion imaging”. These mean the same thing.
Questions worth asking your doctor
- Did this scan use the right technique to answer my question?
- Would contrast, or a different sequence, show something this one could not?
- Do I need another scan, or is this one enough?
How the scan was taken
Where this word comes up
See this word on your own scan
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