Ultrasound May Be Better Option for Kidney Stone Detection

Ultrasound and computerized tomography were comparable diagnostic tools, but ultrasound spared the radiation

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) CT scans and ultrasounds are both imaging techniques used to find kidney stones, and new research suggests they are both effective. But one option may expose patients to less radiation.

Computerized tomography (CT) scans, the most prevalent method, were found to be just as effective as ultrasounds, which spare the patient exposure to potentially harmful radiation.

The study authors recommended ultrasounds as the first step in diagnosing kidney stones.

"Seek medical care for kidney stones."

When diagnosing kidney stones, doctors most often use CT scans. That method uses X-rays to create a cross-section image of a patient.

Kidney stones form from substances in urine. Symptoms include back pain, blood in the urine, fever, vomiting and a burning sensation when urinating.

Rebecca Smith-Bindman, MD, and colleagues studied the effectiveness of CT scans and ultrasounds in finding kidney stones.

An ultrasound uses sound pressure to see inside a patient. Unlike a CT scan, it doesn’t use radiation.

“Ultrasound is the right place to start,” Dr. Smith-Bindman, a professor at the University of California San Francisco, said in a press statement. “Radiation exposure is avoided, without any increase in any category of adverse events, and with no increase in cost."

Patients thought to have kidney stones were assigned to three groups. The first group of 908 patients had an ultrasound by an emergency room doctor, 893 had an ultrasound from a specialist and 958 had a CT scan.

Outcomes were the similar across all three groups. The risk of complications was less than 1 percent for all groups.

In the ER ultrasound group, 12.4 percent returned to the ER or were hospitalized. That measure was 10.8 percent and 11.2 percent for the specialist group and CT scan group, respectively.

"New technology is developed all the time, and it's hard to know when the new, sophisticated and expensive technology is better — in this case the simpler, cheaper, no-radiation technology is just as good," Dr. Smith-Bindman said.

The study was published online Sept. 17 in the New England Journal of Medicine.

The Agency for Healthcare Research and Quality funded the research. The authors disclosed no conflicts of interest.

Review Date: 
September 17, 2014
Last Updated:
September 18, 2014