What can ultrasound show?
Ultrasound uses sound waves to examine the kidneys and parts of the urinary tract without ionising radiation. It can show stones or enlargement caused by urine collecting behind a blockage. Small stones and stones in some parts of the ureter may be difficult to see. A scan that does not show a stone therefore does not exclude one in every clinical situation. [1]
When is CT considered?
Non-contrast computed tomography can give detailed information about stone size and location. A clinician may consider it when ultrasound leaves uncertainty or another cause of pain needs investigation. CT involves radiation, so age, previous examinations and possible pregnancy matter. Imaging during pregnancy requires a separate assessment of the available methods. [1]
Why are blood and urine tests needed?
Blood tests provide information about kidney function and certain minerals. Urinalysis may identify blood, inflammatory cells or crystals; a culture may be needed when infection is suspected. Finding crystals in urine does not necessarily mean that a stone will be visible on imaging. These findings are interpreted alongside symptoms and scans. [1, 2]
Location matters as well as size
Two stones with the same diameter can require different follow-up because of their location. The side, whether the stone is in the kidney or ureter, and any widening of the urinary tract are separate findings. When comparing reports, consider the imaging method and location as well as the measurement in millimetres. A number copied from a report does not provide the full clinical picture.
Questions for the follow-up visit
Useful questions include where the stone is, whether it obstructs urine flow, whether infection is suspected and how follow-up will confirm progress. Bringing previous images as well as written reports helps the team compare findings and avoid unnecessary repetition. Fever, inability to pass urine or severe uncontrolled pain warrants urgent assessment rather than waiting for a scheduled visit. [1, 3]
References
This article provides general health information. Consult your clinician for individual diagnosis and treatment decisions, and your pharmacist for questions about medicine use.
Published by Aymed İlaç · 17 October 2026