Kidney Stones

Diagnosis

X-ray shows both kidneys full of large stones.

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The urogram and the CT scan are the preferred ways at Mayo to diagnose kidney stones. Ultrasound is an option but may not detect small stones.

Intravenous Pyelography (Excretory Urogram)

A contrast dye is injected into the patient's vein, and a series of X-rays is taken as the dye moves from the bloodstream into the kidneys, ureters and bladder. If abnormalities are seen, the doctor may follow up with a CT scan — a series of thin X-ray beams that produce two-dimensional images of the organs.

Spiral CT Scan

This high-speed imaging test is used for patients who cannot tolerate contrast dye. A CT scan checks the abdomen in three minutes, and can reveal the presence of very small kidney stones that do not appear on conventional X-rays.

Ultrasound

These high-frequency radio waves allow physicians to look at a patient's internal organs. This test is painless and noninvasive, but it may not detect small stones, especially those outside the kidneys.