Placental MRI: Developing Accurate Quantitative Measures of Oxygenation

Area of Science:

• Biomedical Imaging
• Obstetrics
• Physiology

Background:

• Noninvasive monitoring of placental function is crucial for managing pregnancy-related pathologies.
• Magnetic resonance imaging (MRI) offers potential for real-time assessment of placental health.
• Oxygen transport is a key placental function influenced by MRI signal intensity.

Purpose of the Study:

• To review current MRI techniques for quantifying placental oxygen transport and content.
• To highlight the challenges and future directions in validating placental MRI methods.
• To emphasize the need for robust and standardized MRI techniques for clinical use.

Main Methods:

• Overview of existing MRI techniques, including blood oxygen level-dependent (BOLD) imaging and MRI relaxometry.
• Discussion of ex vivo and animal studies for validating placental MRI methods.
• Exploration of oxygen quantification using MRI signal changes.

Main Results:

• BOLD imaging during maternal hyperoxia correlates with twin pregnancy outcomes, indicating MRI's potential for monitoring oxygen transport.
• MRI relaxometry methods are being developed to quantify baseline placental oxygenation.
• Direct validation of placental MRI techniques remains a significant challenge.

Conclusions:

• Current MRI techniques show promise for assessing placental oxygen transport and function noninvasively.
• Robustness, reliability, and standardization across individuals are essential for developing predictive diagnostic models.
• While clinical benefits are still several years away, the potential for personalized diagnosis and real-time monitoring of placental disease is a strong motivator.