Foetal Radiation Dose During Prophylactic Occlusion Balloon Placement for Morbidly Adherent Placenta

Objective: To assess foetal absorbed radiation dose (FAD) during prophylactic occlusion balloon catheter (POBC) placement before surgery for morbidly adherent placenta (MAP). Methods: Retrospective cohort study of women with MAP undergoing POBC before surgery. Women were divided into two groups. Group 1 treated between 2008 and 2011, Group 2 between 2012 and 2014 when fluoroscopy pulse rate reduced from 7.5 to 2 pulses per second. Median and interquartile range (IQR) of dose area product (DAP) and FAD were compared using the Mann-U-Whitney test. FAD was calculated using the PCXMC Monte-Carlo calculation. All procedures were performed using the same equipment (Siemens Axiom Artis dTA) by the same experienced interventional radiology team. Results: Thirty-four women underwent POBC. 16 procedures were performed in Group 1 and 18 in Group 2. Median DAP overall was 1025.10 µGym2 (IQR 532.1–1775.3): Group 1, 1713.25 µGym2 (IQR 1164.5–2274.5) and Group 2, 660.70 µGym2 (IQR 440.9–1020.9) (p = 0.027). Median FAD overall was 4.65 mGy (IQR 2.7–8.2): Group 1, 6.25 mGy (IQR 4.4–10.6) and Group 2, 3.05 mGy (IQR 2.0–5.4) (p = 0.031). Conclusions: FAD during POBC insertion is low overall. The only change between the two groups was in pulsed fluoroscopy rate which resulted in a significant reduction in FAD. This reinforces the importance of implementation of dose reduction techniques.