Fetal Radiation Dose in Common Diagnostic Radiology Procedures for Pregnant Patients: Findings from In-Phantom Measurements

The diagnosis of emergent conditions during pregnancy can be delayed due to insufficient knowledge of fetal radiation doses in different imaging modalities. The aim of this article is to investigate the ranges of fetal doses in most common diagnostic and interventional radiology procedures. Procedures were carried out on an anthropomorphic phantom, Tena, representing a pregnant woman in the 18th week of pregnancy with the fetus in breech position. Different clinical scenarios using computer tomography (CT), radiography, fluoroscopy and digital subtraction angiography were selected in three teaching hospitals. Measurements were performed using radiophotoluminescent glass dosimeters placed in dedicated holes in the fetal head and fetal body. Measured fetal doses were below 1 mGy when the fetus was not in the primary beam. The highest fetal doses, up to 47 mGy, were measured after a CT scan for polytrauma and up to 24 mGy after a CT scan of the abdomen and pelvis. Significant variability in fetal doses for the same procedure was found between different hospitals but within the same hospital also. All obtained results are below the threshold for deterministic effects given by the International Commission for Radiation Protection but can be reached with two or more imaging procedures employed. The variability in fetal doses for the same procedures highlights the need for the improved optimization of imaging protocols.