Optimisation of multislice computed tomography protocols in angio-CT examinations.
PURPOSE: The aim of this paper is to explain a general procedure for the optimisation of multislice computed tomography (MSCT) protocols. MATERIALS AND METHODS: Four angio-CT protocols with a GE LightSpeed Plus 4-slice CT scanner were considered. Effective doses were computed for a sample of patients. First the dose was optimised for arterial-phase scans on a standard patient and adapted to the weight of individual patients with a scaling factor. RESULTS: The mean effective dose for an angio-CT examination ranged from 18.8 mSv to 28.8 mSv, depending on the protocol adopted. Following the optimisation procedure, we drew up a table indicating tube current values for each patient weight. Calculation of the effective dose before and after the optimisation procedure revealed a dose reduction of about 40%. CONCLUSIONS: Angio-CT examinations deliver high doses, but these doses can be reduced without affecting image quality.