Kidney stones are small, hard deposits that form inside your kidneys. The stones are made of mineral and acid salts. Kidney stones have many causes and can affect any part of your urinary tract — from your kidneys to your bladder. Often, stones form when the urine becomes concentrated, allowing minerals to crystallize and stick together.

Passing kidney stones can be quite painful, but the stones usually cause no permanent damage. Depending on your situation, you may need nothing more than to take pain medication and drink lots of water to pass a kidney stone. In other instances, surgery may be needed. We recommend preventive treatment to reduce your risk of recurrent kidney stones.

A patient with pain consistent with a kidney stone, or any of the other symptoms listed above will be imaged to determine if a kidney stone is present, where it is located, and how large it is. Several different diagnostic imaging techniques are available to accomplish these goals:

• X-ray imaging is able to see calcium that is in the majority of stones.
• Ultrasound is an easy to use and relatively inexpensive technology that can detect the swelling of the kidney caused when a stone obstructs flow of urine.
• A CT scan without contrast is the gold-standard (best) diagnostic test for detecting kidney stones.