Australian researchers are warning about the potential additional radiation risk and financial cost to patients who undergo multiple CT scans, which may be avoidable or unnecessary, according to a study published online on 5 February in the Journal of Medical Imaging and Radiation Oncology.
The retrospective study, led by Dr. Penni Blazak from Sunshine Coast University Hospital in Birtinya, Queensland, reviewed clinical records of 247 trauma and neurosurgical patients who were transferred to its tertiary intensive care unit from other hospitals for CT scans over a 13-month period from June 2013 to June 2014.
The researchers estimated the additional effective radiation dose the patients received and costs associated with CT scans based on the Australian Medicare Benefits Schedule.
Of the 247 transferred patients, 144 people (58%) had undergone CT imaging at the referring hospital. Repeat CT scans were performed in 60 of those cases (42%; 24% of all transferred patients), most frequently for changes in clinical indications.
Follow-up CT scans at Sunshine Coast University Hospital resulted in changes in care management for 11 patients (18%), while Blazak and colleagues determined that repeat scans were potentially avoidable in 13 cases (22%).
The researchers also calculated the median cost of a repeat scan was $250 Australian dollars (160 euros) and the median additional effective radiation dose was 2.74 mSv per patient.
"Repeat CT scans for patients already imaged prior to transfer were relatively common, occurring mostly for apparently valid clinical reasons," Blazak and colleagues wrote in their abstract. "However, the additional radiation risk and financial cost of these repeat scans appeared on retrospective audit to be potentially avoidable in approximately one in five cases."
