Magnetic resonance imaging in the evaluation of the fetal spinal canal contents.

Ultrasonography (US) remains the first method in the evaluation of fetal central nervous system (CNS) abnormalities but in case of the spinal canal and cord it is often insufficient since the bony structures may obscure these structures. Prenatal magnetic resonance imaging (MRI) is therefore the final noninvasive tool for the assessment of these malformations allowing for correction of sonographic findings, revealing the full extent of complex lesions and choosing the candidates for in utero treatment. The authors present the most frequent anomalies of spinal canal and spinal cord in the consecutive phases of pregnancy, illustrated with their own MR images, with reference to the literature and own experience. In 58 out of 252 fetuses examined due to suspicion of CNS anomalies (23.0%) the spinal canal and spinal cord abnormalities were found on MRI. The cases of diastematomyelia, myelomeningocele, tethered cord, caudal regression syndrome, anterior meningocele, cystic sacrococcygeal teratoma and syringohydromyelia are demonstrated.