purpose We examined trends in utilization of computed tomography (CT) among Medicaid enrollees in North Carolina, the clinical setting in which those CT scans were performed, and the number of enrollees known to have undergone 10 or more scans in a given year. methods North Carolina Medicaid claims were analyzed to determine the number of CT studies performed between January 1, 2007, and December 31, 2012. We assessed the number of "high exposure" patients-those who received 10 or more CT scans in a given calendar year-and divided this group into patients with a diagnosis of cancer and patients without a diagnosis of cancer. We also determined the type of site at which each CT scan was performed. conclusions Although the number of CT scans performed annually in the North Carolina Medicaid population stabilized in the late 2000s (as did CT use nationally), the percentage of high-exposure patients has continued to rise. Physicians and patients need to be further educated in order to promote radiation safety and to decrease unnecessary radiation exposure.

background Patients are being exposed to increasing levels of ionizing radiation, much of it from computed tomography (CT) scans. methods Adults without a cancer diagnosis who received 10 or more CT scans in 2010 were identified from North Carolina Medicaid claims data and were sent a letter in July 2011 informing them of their radiation exposure; those who had undergone 20 or more CT scans in 2010 were also telephoned. The CT scan exposure of these high-exposure patients during the 12 months following these interventions was compared with that of adult Medicaid patients without cancer who had at least 1 CT scan but were not in the intervention population. results The average number of CT scans per month for the high-exposure population decreased over time, but most of that reduction occurred 6-9 months before our interventions took place. At about the same time, the number of CT scans per month also decreased in adult Medicaid patients without cancer who had at least 1 CT scan but were not in the intervention population. limitations Our data do not include information about CT scans that may have been performed during times when patients were not covered by Medicaid. Some of our letters may not have been received or understood. Some high-exposure patients were unintentionally excluded from our study because organization of data on Medicaid claims varies by setting of care. conclusion Our patient education intervention was not temporally associated with significant decreases in subsequent CT exposure. Effecting behavior change to reduce exposure to ionizing radiation requires more than an educational letter or telephone call. 103NCMJ vol. 75, no. 2 ncmedicaljournal.com their risks [22,23]. Recently a large hospital system also launched a program that allows patients and physicians to get information from the patient's electronic health record about his or her radiation exposure within that hospital system [24]. However, the literature does not include any largescale efforts by insurers to reach high-exposure patients, nor are there any follow-up studies of the effect of such outreach efforts.Community Care of North Carolina (CCNC) is a nonprofit organization that partners with the North Carolina Division of Medical Assistance (DMA), which operates the state's Medicaid program. One of CCNC's goals is to promote wellness by reinforcing each Medicaid recipient's relationship with his or her primary care medical home [25]. Through 14 regional networks consisting of physicians, nurses, pharmacists, care managers, and other staff, CCNC has ongoing care improvement projects including state-level efforts, region-specific pilots, and projects focused on specific patient populations.In one state-level project, a team of physicians, nurses, analysts, and DMA staff members review outlier claims to see whether unusual billing patterns indicate a need for changes in policies or care pathways. A physician on this team had seen a patient who questioned the safety of the high number of CT scans he had received during the past ye...

A dual radionuclide subtraction technique for external detection of tumours has been evaluated to determine the viability of the method for use with radioisotope labelled antibodies. A number of external scintigraphic investigations have been carried out with 131I-labelled antibodies to carcinoembryonic antigen (CEA). The investigations were performed on patients with metastatic disease known to produce CEA. The dual radionuclide subtraction technique was used to account for the blood and tissue background. The 131I-labelled antibodies were found to localise in the metastatic lesions, but the subtraction technique using 99Tcm-labelled HSA and pertechnetate gave ambiguous results, which included the production of artefacts. The ambiguities noted in the clinical results were substantiated by experimental data, which highlight the unreliability of this technique.