What does Restricted diffusion mean on an imaging report?
Restricted diffusion is an MRI finding where water movement in tissue is limited. It can be seen in some tumors but also in other conditions like inflammation. Radiologists read it together with the rest of the scan.
Also written as
- diffusion restriction
- DWI
Please read: This page explains general report language and cannot interpret your personal report, diagnose a condition, judge how serious a result is, or recommend treatment. Only your care team can do that.
How to read scan & imaging results
An imaging report is a radiologist's description of what a scan showed, written in careful, hedged language because a picture can suggest but rarely prove what something is. Words like 'suspicious,' 'indeterminate,' or 'cannot exclude' describe how a finding looks, not a diagnosis, and many findings that need a closer look turn out to be harmless after follow-up. Comparing a scan with earlier ones and, when needed, confirming with a biopsy is often what settles the question. The doctor who ordered the scan puts the report together with your history and exam.
Questions to ask your care team
- What does this finding most likely represent?
- Does it need a follow-up scan, a biopsy, or just watching?
- How does it compare with my earlier scans?
- Does this change my diagnosis or treatment plan?
Related scan & imaging terms
- LesionA lesion is a general word for an area that looks different from the tissue around it on a scan or exam.
- MassA mass is an area of tissue that looks thicker or denser than usual on a scan.
- NoduleA nodule is a small, rounded spot seen on a scan.
- Ground-glass opacityA ground-glass opacity is a hazy area on a lung scan where you can still see some detail through it.
- OpacityAn opacity is an area on a scan that blocks more of the imaging beam than usual, so it looks lighter.
- EnhancementEnhancement means an area lights up after contrast dye is given during a scan.
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