Combined CT pulmonary angiography and venography for diagnosis of pulmonary embolism and deep vein thrombosis: Radiation dose

A major concern about combined pulmonary CT angiography (PCTA) and CT venog raphy (CTV) refers to the additional radiation exposure to the patient. The purpose of this paper is to analyze the organ dose, the effective dose, an d the gonadal dose of combined PCTA and CTV. Effective dose and gonadal dos e in PCTA and CTV were calculated. Also measured was the organ doses with t hermoluminescence dosimeters in six patients who underwent combined PCTA/CT V. The risk from the effective dose and gonadal dose in combined PCTA/CTV i s low. Nevertheless, additional CTV increases the gonadal dose by a signifi cant factor and use of this procedure should be limited in younger patients .