Evaluation of image quality and fetal dose through current modulation CT-scan using pregnancy phantoms.

Abstract

Computed Tomography (CT) is often required in special circumstances during pregnancy to determine internal medicine, specifically when information from other imaging techniques, such as ultrasound and magnetic resonance imaging (MRI), is still inadequate. In CT-Chest, abdomen, and pelvis (CAP) examination, direct irradiation of the fetal is necessary, indicating that the potential for fetal exposure must be considered. Therefore, this study evaluated the effects of current modulation on image quality and fetal absorbed dose in pregnancy CT scan. Calculation using IndoseCT and film dosimeters were used with a 3D-printed anthropomorphic pregnant phantom thorax-abdomen-pelvic during the first and third trimesters of pregnancy. Image quality analysis and image noise were then measured by IndoseCT, while fetal dose analysis was performed using IndoseCT software, as well as through direct measurements with an XR-QA2 film dosimeter. Statistical tests were performed to compare the data obtained using both methods. The results showed that the use of current modulation increased the image noise. The fetal dose can be significantly reduced by adjusting the tube current and patient diameter without affecting image quality in the first and third trimesters. It was also revealed that the smallest diameter received the largest dose in both trimesters for nonmodulation. Although there were differences in the dose values obtained from the IndoseCT and measurements, the data patterns were not significantly different. Furthermore, based on these results, the dosage value was below the tolerance threshold for deterministic effects (i.e., <50 mGy).