Skip to Main Content

We have a new app!

Take the Access library with you wherever you go—easy access to books, videos, images, podcasts, personalized features, and more.

Download the Access App here: iOS and Android



  1. There is scarce information regarding the diagnostic criteria of midbrain-hindbrain anomalies in fetuses; cerebellar malformations are better understood, although there are still many overlaps between entities, and the rate of misdiagnosis is still high.

  2. Brainstem anomalies comprise a heterogenous group of malformations and degenerative diseases of different etiologies. In contrast with the postnatal period, when abnormalities are mostly related to insults and vascular anomalies, during the prenatal period these anomalies are usually developmental and present different imaging features at different gestational ages.

  3. The 2009 classification of midbrain-hindbrain anomalies assorts brainstem anomalies to four main groups based upon genetic and embryologic criteria (Table 11–1).1

  4. Prenatal diagnosis is of utmost importance due to the high rate of neurodevelopmental impairment and the genetic implications of these entities.

  5. Dedicated neurosonography is the modality of choice for diagnosis in the first and second trimesters, with accurate characterization of features upon utilization of correct insonation technique. Fetal MRI is an important complementary tool for the assessment of these disorders, contributing significantly when ultrasound has poor technical quality, expert neurosonography is not available, or during the third trimester of pregnancy.



The embryonic structures of the midbrain and hindbrain (MB-HB) and their differentiation process into the brainstem (BS) and cerebellum have been the focus of recent research in the fields of neurogenetics, developmental biology, and fetal neuroimaging. The last classification system proposed and accepted worldwide for MB-HB anomalies (either developmental or acquired) was published by Barkovich et al in 2009, and it is based on genetic and developmental criteria, with an attempt to establish more accurate diagnostic features than those based on imaging, with significant overlap between entities (Table 11–1).1

Prenatal diagnosis of MB-HB anomalies is of the ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.