What does “Hydronephrosis” mean on a radiology report?
Swelling of the urine-collecting part of a kidney because urine is not draining freely, for example because of a stone or narrowing further down.
How "Hydronephrosis" is used in radiology reports
Urine is made in the kidneys and collects in a funnel-shaped space inside each one (the renal pelvis) before draining down the ureter to the bladder. If drainage is held up — by a kidney stone, a narrowing, pressure from outside, an enlarged prostate, or in pregnancy — urine backs up and that collecting space swells. That swelling is hydronephrosis. If the ureter is widened too, reports may say hydroureteronephrosis.
Radiologists usually grade it as mild, moderate or severe, and look for the cause. Ultrasound shows it well and is often the first test; CT can show both the swelling and a stone causing it. The sentence "no hydronephrosis" is one of the most common reassuring negatives on a kidney scan.
Mild hydronephrosis can be temporary — a full bladder or pregnancy can cause it — and the significance always depends on the cause and on kidney function, which is checked with blood tests. Your doctor decides what, if anything, needs doing.
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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.
Does this mean something is wrong?
Not on its own. A radiology report describes what the images show, in language written for the doctor who ordered the scan. One term is rarely the whole picture — what it means for you depends on why you were scanned and what else the report says.
If the report worries you, the person who can actually answer that is the doctor who referred you. Understanding the words first usually makes that conversation a better one.
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Other pathology terms
- AbscessA pocket of pus that forms due to infection. Appears as a fluid-filled cavity on imaging.
- AdenopathySwollen or enlarged lymph nodes, often indicating infection or disease.
- AtelectasisPartial collapse of the lung tissue, preventing normal air exchange.
- AtrophyWasting away or decrease in size of tissue or organs.
- BenignNot cancerous. A benign growth is non-life-threatening.
- BronchiectasisAbnormal widening of the airways in the lungs, often from chronic infection.
This explains a term as it is commonly used in radiology reports. It is not a diagnosis and not medical advice. Discuss your own results with your doctor.