Comparison of the T2-star Values of Placentas Obtained from Pre-eclamptic Patients with Those of a Control Group: an Ex-vivo Magnetic Resonance Imaging Study

Abstract

Background: Endotel dysfunction, vasoconstriction, and oxidative stress are described in the pathophysiology of pre-eclampsia, but its aetiology has not been revealed clearly. Aims: To examine whether there is a difference between the placentas of pre-eclamptic pregnant women and those of a control group in terms of their T2 star values. Study Design: Case-control study. Methods: Twenty patients diagnosed with pre-eclampsia and 22 healthy controls were included in this study. The placentas obtained after births performed via Caesarean section were taken into the magnetic resonance imaging area in plastic bags within the first postnatal hour, and imaging was performed via modified DIXON-Quant sequence. Average values were obtained by performing T2 star measurements from four localisations on the placentas. Results: T2 star values measured in the placentas of the control group were found to be significantly lower than those in the pre-eclampsia group (p<0.01). While the mean T2 star value in the pre-eclamptic group was found to be 37.48 ms (standard deviation ± 11.3), this value was 28.74 (standard deviation ± 8.08) in the control group. The cut-off value for the T2 star value, maximising the accuracy of diagnosis, was 28.59 ms (area under curve: 0.741; 95% confidence interval: 0.592-0.890); sensitivity and specificity were 70% and 63.6%, respectively. Conclusion: This study, the T2 star value, which is an indicator of iron amount, was found to be significantly lower in the control group than in the pre-eclampsia group. This may be related to the reduction in blood flow to the placenta due to endothelial dysfunction and vasoconstriction, which are important in pre-eclampsia pathophysiology.

Keywords

• Ex vivo, magnetic resonance imaging, placenta, pre-eclampsia, T2 star

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