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

Abstract

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.