Do UVJ stones look bigger on ultrasound?

Stone Fighter #2EEB2FMay 10, 2026

My ultrasound said my stone was 6mm. Then my urologist got back to me and said it was probably closer to 3mm—ultrasounds always overestimate the size.

Stone Fighter #72299FMay 10, 2026

Absolutely. Ultrasound mainly relies on acoustic shadows, which is kind of like making hand shadows on a wall—the shadow looks way bigger than your actual hand. Ultrasound has its uses in imaging, but accurately diagnosing small stones or measuring kidney stone size isn't one of them. It tends to overestimate size—sometimes by double—and misses a lot of smaller stones. For small stones, the average overestimate is more than 2mm. The gold standard for kidney stone imaging is CT-KUB, both for...