DOES THE USE OF CONTEMPORARY CT SCANNERS ALTER THE RADIATION DOSE DEBATE IN THE IMAGING WORK UP FOR PULMONARY EMBOLISM

: The aim of this study was to compare patient doses from ventilation perfusion single photon emission computed tomography (V/Q SPECT) and computed tomography pulmonary angiography (CTPA) performed on contemporary scanners. Effective dose (ED) for V/Q SPECT was calculated using organ doses per unit administered activity of the radiopharmaceuticals. Organ doses in CT were measured using nanoDot aluminium oxide optically stimulated dosemeters placed within a female adult anthropomorphic phantom. To simulate a larger patient, the phantom was wrapped in three layers of Superflab sheets. The V/Q SPECT resulted in ED of 2.82 mSv and a breast dose of 1.12 mGy. The CTPA dose was 1.82 ± 0.42 and 3.43 ± 0.91 mSv, whilst dose to the breast tissue was 2.86 ± 0.86 and 5.95 ± 0.44 mGy for small- and medium-sized patients, respectively.