MRI in Pregnancy and Precision Medicine: A Review from Literature

Abstract

Magnetic resonance imaging (MRI) offers excellent spatial and contrast resolution for evaluating a wide variety of pathologies, without exposing patients to ionizing radiations. Additionally, MRI offers reproducible diagnostic imaging results that are not operator-dependent, a major advantage over ultrasound. MRI is commonly used in pregnant women to evaluate, most frequently, acute abdominal and pelvic pain or placental abnormalities, as well as neurological or fetal abnormalities, infections, or neoplasms. However, to date, our knowledge about MRI safety during pregnancy, especially about the administration of gadolinium-based contrast agents, which are able to cross the placental barrier, is still limited, raising concerns about possible negative effects on both the mother and the health of the fetus. Contrast agents that are unable to cross the placenta in a way that is safe for the fetus are desirable. In recent years, some preclinical studies, carried out in rodent models, have evaluated the role of long circulating liposomal nanoparticle-based blood-pool gadolinium contrast agents that do not penetrate the placental barrier due to their size and therefore do not expose the fetus to the contrast agent during pregnancy, preserving it from any hypothetical risks. Hence, we performed a literature review focusing on contrast and non-contrast MRI use during pregnancy.

Keywords: MRI; gadolinium; liposomal gadolinium; precision medicine; pregnancy; safety during pregnancy.

Figure 1

Liposomal nanoparticle-based blood-pool gadolinium contrast agent structure. Low molecular-weight gadolinium-chelated (in red) is inserted, both core-encapsulated and surface-conjugated, in liposome structures made of phospholipid bilayer (in light blue). The liposomes are also coated with PEG (in purple) and thus avoid penetration through placental barrier.