Magnetic resonance imaging in obstetrics.

UNLABELLED: Ultrasonography is the primary screening modality for obstetrics imaging. When additional information is needed to care for pregnant patients, computed tomography and magnetic resonance imaging (MRI) can be used. Because MRI provides superior contrast resolution compared with CT, uses no ionizing radiation, and permits imaging in more than one plane, it has been used in feto-maternal imaging. This article presents principles, practical aspects and indications of MRI in obstetrics: diagnosis of fetal anomalies, prenatal counseling and management, placental position and placenta praevia, pregnant patient with associated pathology (e.g. acute abdomen, hydronephrosis, adnexal masses) and pelvimetry. The article presents, also, fetal central nervous system malformations (one of the most frequent indication of MRI in obstetrics) and other fetal anomalies like diaphragmatic hernia or gastroschisis.

CONCLUSIONS: Ultrasound continues to be the screening modality of choice in the evaluation of the fetus. Proper use and interpretation of ultrasound limits the cases in which magnetic resonance is necessitated. However, there are many cases in which MRI alternative imaging is useful, complementary to ultrasounds.