People who get steroid injections to ease back pain do not need an MRI scan, which does little to help doctors assess and treat patients but adds significant costs, U.S. researchers said on Monday.

Steroid injections in the back are among the most common treatments at pain clinics, and doctors routinely order a magnetic resonance imaging, or MRI, scan before treatment.

At $1,500 each, these scans are a costly addition that may not be necessary, says Dr. Steven Cohen of Johns Hopkins University School of Medicine, whose study appears in the Archives of Internal Medicine.

“Our results suggest that MRI is unlikely to avert a procedure, diminish complications or improve outcomes,” Cohen said in a statement.

Given how often these procedures are done, skipping the MRI beforehand could save significant time and money, he said.

Medical imaging tests have revolutionized health care, giving doctors a way to look inside the body to make better decisions and help avoid unnecessary treatments.

But recently, doctors have come under fire for ordering too many unnecessary imaging tests, adding to the U.S. health care bill.

Cohen and colleagues studied patients with sciatica, a common back problem in which a nerve that starts in the lower back becomes pinched, causing shooting pain and tingling in the spine and down the leg.

Doctors often treat the condition by injecting the long-acting steroid cortisone into the epidural space that surrounds the spinal cord.

Cohen and his colleagues treated 132 patients with this condition. All got an MRI before, but doctors didn’t look at the test results before treatment in half of the patients. Instead, they gave the injections based on their exam of the patients.

In the second group, doctors based their treatment on a physical exam and used MRI to help decide where to place the needle or whether to given an injection at all.

Three months later, there was no difference between the groups. In the MRI-blind group, 23 patients called the treatment an “overall success” compared with 24 patients in the group whose doctors used the MRI to guide their treatment.

Cohen said the findings offer just one example of ways doctors can cut back on costly imaging tests.

Treating spine problems in the United States costs $85.9 billion a year, rivaling the economic burden of treating cancer, which costs $89 billion, according to a 2008 study published in the Journal of the American Medical Association.

The study cited advanced diagnostic tests as a key driver in the cost of treating back pain, along with prescription drugs and frequent outpatient visits.

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(Reuters)