Assessment of feto-placental oxygenation and perfusion in a rat model of placental insufficiency using T2 mapping and 3D dynamic contrast-enhanced MRI

• Published in: Placenta (Eastbourne) Vol. 151; pp. 19 - 25
• Main Authors: Al Darwish, Fatimah M., Coolen, Bram F., van Kammen, Caren M., Alles, Lindy K., de Vos, Judith, Schiffelers, Raymond M., Lely, Titia A., Strijkers, Gustav J., Terstappen, Fieke
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.06.2024
• Subjects: Animals; Contrast Media; Disease Models, Animal; Female; Fetal growth restriction; Hypoxia; Imaging, Three-Dimensional - methods; Magnetic Resonance Imaging - methods; Oxygen - metabolism; Placenta - blood supply; Placenta - diagnostic imaging; Placenta - metabolism; Placenta imaging; Placental Circulation - physiology; Placental Insufficiency - diagnostic imaging; Placental Insufficiency - metabolism; Placental oxygenation; Pregnancy; Rats; Rats, Sprague-Dawley; RUPP; Hypoxia; Placental oxygenation; Placenta imaging; RUPP; Fetal growth restriction
• ISSN: 0143-4004; 1532-3102; 1532-3102
• DOI: 10.1016/j.placenta.2024.04.008

Placental insufficiency may lead to preeclampsia and fetal growth restriction. There is no cure for placental insufficiency, emphasizing the need for monitoring fetal and placenta health. Current monitoring methods are limited, underscoring the necessity for imaging techniques to evaluate fetal-placental perfusion and oxygenation. This study aims to use MRI to evaluate placental oxygenation and perfusion in the reduced uterine perfusion pressure (RUPP) model of placental insufficiency. Pregnant rats were randomized to RUPP (n = 11) or sham surgery (n = 8) on gestational day 14. On gestational day 19, rats imaged using a 7T MRI scanner to assess oxygenation and perfusion using T2* mapping and 3D-DCE MRI sequences, respectively. The effect of the RUPP on the feto-placental units were analyzed from the MRI images. RUPP surgery led to reduced oxygenation in the labyrinth (24.7 ± 1.8 ms vs. 28.0 ± 2.1 ms, P = 0.002) and junctional zone (7.0 ± 0.9 ms vs. 8.1 ± 1.1 ms, P = 0.04) of the placenta, as indicated by decreased T2* values. However, here were no significant differences in fetal organ oxygenation or placental perfusion between RUPP and sham animals. The reduced placental oxygenation without a corresponding decrease in perfusion suggests an adaptive response to placental ischemia. While acute reduction in placental perfusion may cause placental hypoxia, persistence of this condition could indicate chronic placental insufficiency after ischemic reperfusion injury. Thus, placental oxygenation may be a more reliable biomarker for assessing fetal condition than perfusion in hypertensive disorders of pregnancies including preeclampsia and FGR. •The RUPP model shows a decrease in placental oxygenation five days after surgery.•Stable fetal organ oxygenation was observed following RUPP surgery.•The RUPP model insights guide imaging and therapeutic strategies development.•Placental oxygenation metrics may serve as biomarkers for assessing fetal health.