Is your hospital a hotspot for doubling up on CT scans? NYT interactive map makes it easy to see

The hotter the color on this map, the more likely the local hospital is to be doubling up on computerized tomography (CT) scans, part of a phenomenon costing Medicare an extra $25 million a year and exposing patients to radiation without it being medically necessary, according to an analysis of data by The New York Times. Typically, one scan will use iodine to check blood flow and one will not. "Radiologists say one scan or the other is needed depending on the patient’s condition, but rarely both," Walt Bogdanich and Jo Craven McGinty report.

Nationally, 5.4 percent of outpatients on Medicare got two scans in one day during 2008. At major teaching hospitals the rate was usually less than 1 percent, but at more than 200 hospitals the average was more than 30 percent. Those over 25 percent are marked by red dots on the map, those between 15 and 25 percent with yellow dots, and those below 15 percent with blue. Data for 2009, which are very similar, are to be released next month by the Centers for Medicare and Medicaid Services. (Click on map to get interactive version with data for individual hospitals)

"Double scans expose patients to extra radiation while heaping millions of dollars in extra costs on an already overburdened Medicare program," the Times points out. "A single CT scan of the chest is equal to about 350 standard chest X-rays, so two scans are twice that amount. . . . 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," according to Dr. Michael J. Pentecost, a radiologist who reviews claims for CT scans.

The phenomenon appears more prevalent at rural hospitals. "Dr. Harold Smitson, who helps to oversee radiology at two East Texas Medical Center hospitals with high double-scan rates, told the Times, “These are small and rural hospitals, without a complete range of medical services, which are mandated to evaluate patients quickly and efficiently to determine the need for transfer to a higher level of care. ... “Combining these tests expedites the diagnosis and the care to the patient.” (Read more)

East Texas was one of the rural hotspots; ETMC Fairfield's double-scan rate was 88 percent, one of the highest in the nation. Another rural hotspot was in Tennessee and adjoining areas of Virginia and Kentucky. The highest in the region was Livingston Regional Hospital, at 87 percent.