Foetal radiation exposure caused by mechanical thrombectomy in large-vessel ischaemic stroke in pregnancy

There is overwhelming evidence for the clinical benefits that are derived following mechanical thrombectomy in large-vessel acute ischaemic stroke. The risk of stroke is elevated in pregnancy due to many factors. To date, there have been two reports, totalling five patients, who have undergone mechanical thrombectomy in pregnancy, thus demonstrating the feasibility of the procedure; however, there is no data on the radiation exposure to the mother or foetus related to this therapy.

We highlight the important technical considerations to minimise the risk of the procedure and report the estimated dose received by mother and foetus. We also compare these doses with those received during whole-body CT in trauma and CT pulmonary angiogram (CTPA) examinations.

Three cases of mechanical thrombectomy were performed at separate tertiary referral neuroscience centres in the UK. Following diagnostic CT and mechanical thrombectomy, the total whole-body effective dose to the pregnant patient was significantly higher than in patients undergoing CTPA (p < 0.05), but not significant different compared to whole-body CT imaging in trauma patients. The estimated dose received by the foetus following diagnostic CT and mechanical thrombectomy was significantly lower than in whole-body imaging in trauma patients at p < 0.05, with no difference in estimated foetal dose compared to CTPA imaging.

The estimated doses received by the foetus during diagnostic stroke imaging and mechanical thrombectomy are equivalent to, or less than, purely diagnostic imaging in emergency situations.