To explain examination technique, advantages, limitations and indications of fetal magnetic resonance imaging (MRI) on the evaluation of thoracic congenital malformations.
To describe and to illustrate normal thoracic anatomy and thoracic anomalies on fetal MRI, excluding congenital cardiopathies.
Fetal ultrasound scan remains the modality of choice to fetuses’ morphological evaluation in both low-risk and high-risk pregnancies because of its easy accessibility and low cost. This applies especially to the second-trimester scan, considering the late development of many anatomical structures and its anomalies that make early detection inaccessible. However, antenatal ultrasound has some limitations, such as the need for personal experience and training, maternal obesity, severe oligohydramnios, fetal position, limited field-of-view, lower tissue resolution and method-related artifacts.
Unlike ultrasound, fetal MRI is a complementary...
Findings and procedure details
Fetal MRI becomes increasingly helpful after 22 weeks and 1,5T is the most common used field strength. It is a safe procedure, when performed without administration of contrast media. Fast images acquisition protocols minimize fetal, uterine and respiratory motion artifacts. HASTE (half-Fourier acquisition single-shot turbo spin-echo) and True-FISP (fast imaging with steady-state free precession) are examples of fast sequences that we use in our protocol, acquiring T2-weighted images.
The presence of the radiologist is vital to adjust the field-of-view to the target region...
MRI shows improved anatomical detail when compared to ultrasound. This is particularly usefulin scenarios that lead to difficult sonographic evaluations or in complex cases. Fast acquisition sequences allow better images, reducing artefacts. Therefore, recognizing antenatal imaging features of normal anatomy and thoracic abnormalities at fetal MRI is essential for prenatal parental counseling and adequate patient management.
Personal information and conflict of interest
J Fávero Prietto Dos Santos-nothing to disclose; MC Barreto Da Silva Barros-nothing to disclose; L Vieira Targa-nothing to disclose; APVF Benites Sperb-nothing to disclose; F Fagundes Bassols-nothing to disclose; JA Bianchi Telles-nothing to disclose
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