Long after questions were first raised about the overuse of powerful CT scans, hundreds of hospitals across the country needlessly exposed patients to radiation by scanning their chests twice on the same day, according to federal records and interviews with researchers.
Performing two scans in succession is rarely necessary, radiologists say, yet some hospitals were doing that more than 80 percent of the time for their Medicare
chest patients, according to Medicare outpatient claims from 2008, the most recent year available. The rate is typically less than 1 percent, or in some cases zero, at major university teaching hospitals.
Next month, the Center for Medicare and Medicaid Services is expected to release figures for 2009, but according to people who have seen the numbers, the practice of double scanning chest patients has continued.
"When I saw the 2009 numbers, they were the same essentially, and I was disquieted by that," said Dr. Michael J. Pentecost, a radiologist and Medicare consultant who also reviews claims for commercial clients.
The overuse of scans has been the subject of growing concern in recent years, but a review of the federal data, focusing on a common procedure performed millions of times a year, offers a rare and detailed snapshot of the problem state by state, hospital by hospital.
In 2008, about 75,000 patients received double scans, one using iodine contrast to check blood flow, and one that did not. "If you do both, you bill for both," Dr. Pentecost said.
Radiologists say one scan or the other is needed depending on the patient's condition, but rarely both. Double scanning is also common among privately insured patients who tend to be younger.
Double scans expose patients to extra radiation while heaping millions of dollars in extra costs on an already overburdened Medicare program. A single CT scan of the chest is equal to about 350 standard chest X-rays, so two scans are twice that amount.
"The primary concern relates to radiation exposure," said Dr. James A. Brink, chief of diagnostic radiology at Yale-New Haven Hospital, where double scans accounted for only a fraction of 1 percent of cases. He added: "It is incumbent upon all of us to limit it to the amount needed to make a diagnosis."
Officials at hospitals with high scan rates said radiologists ordered the extra chest scan figuring that more information is better. In rare instances, the two scans might help a doctor distinguish between tangled blood vessels and a tumor, Dr. Pentecost said.
The Medicare agency distributed the data to hospitals last year to show how they performed relative to each other and to encourage more efficient, safer practices. The review of that data found more than 200 hospitals that administered double scans on more than 30 percent of their Medicare outpatients - a percentage that the federal agency and radiology experts considers far too high. The national average is 5.4 percent.
The figures show wide variation among states as well, from 1 percent in Massachusetts to 13 percent in Oklahoma. Overall, Medicare paid hospitals roughly $25 million for double scans in 2008.
Double scanning is more likely to occur at smaller, community hospitals such as Memorial Medical Center of West Michigan in Ludington. It gave two scans to 89 percent of its Medicare chest patients..
"We aren't radiologists, but as we understand the practice, it was strictly a matter of physicians, independent practitioners who were doing their best to get to the bottom of what was ailing their patients," said Bill Kerans, a spokesman for that hospital.
Since 2008, Memorial Medical Center lowered its rate to 42.4 percent in 2010 and to 3 percent in the first part of 2011. "We have made some dramatic changes in protocols and practices," Mr. Kerans said.
A few large hospitals have had problems as well. St. John Health System in Tulsa double-scanned 80 percent - or 800 of its Medicare outpatients in 2008. "We recognized in late 2008 and early 2009 those numbers were higher than we needed to be," said Charles Anderson, the hospital's president and chief executive.
By changing protocols, the percentage of double scans is now "hovering around 5 percent," Mr. Anderson said. "What that means for us is when a physician orders a scan from a radiology department, the radiologist begins to engage in a conversation with those physicians, talking about what might be a more reasonable and acceptable approach."