What does “No hydronephrosis” mean on a radiology report?
The kidneys are not swollen with backed-up urine, which means there is no sign of a blockage in the urine drainage from them.
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General explanations of common wording, not advice about your own scan. Ask the doctor who ordered it what your results mean for you.
Why the radiologist wrote it that way
Urine drains from each kidney down a tube (the ureter) to the bladder. If something blocks that drainage — a kidney stone, a narrowing, an enlarged prostate — urine backs up and the drainage system inside the kidney swells. That swelling is hydronephrosis. Ultrasound and CT check for it on almost every kidney scan, and stating its absence is one of the most useful negatives in a report about pain in the side or kidney function.
Is this good or bad news?
This is a reassuring finding. It means there is no sign of the urine flow from the kidneys being significantly obstructed at the time of the scan. It does not on its own rule out a small kidney stone: a stone can be present without causing a blockage, so the report usually comments on stones separately. If you are scanned for pain in the side, the overall answer depends on both sentences together.
What it does not mean
- That there is no kidney stone at all. Stones are reported separately.
- That kidney function is normal. Function is measured by blood tests, not by this sentence.
Where you will see it
Words in this phrase
One phrase is not the whole report
What this sentence means for you depends on everything else your report says. Radily reads the whole thing and explains it in plain English — and can talk you through it on video, so you are not reading medical language alone.
Other phrases on your report
- No acute intracranial abnormalityThe scan found nothing new or urgent inside the skull — no bleeding, no swelling, no sign of injury needing treatment today.
- UnremarkableNormal. There was nothing worth remarking on.
- Mild degenerative changesOrdinary age-related wear in the joints or spine — the kind almost everyone develops, to some degree, as they get older.
- No acute cardiopulmonary processThe chest X-ray shows no new problem with the heart or lungs — no pneumonia, no fluid around the lungs, no collapsed lung, and a heart that looks a normal size.
This explains how a phrase is commonly used in radiology reports. It is not a diagnosis, not a reading of your scan, and not medical advice. Only your doctor can tell you what your own report means.