Assessment of fetal midbrain and hindbrain in mid‐sagittal cranial plane by three‐dimensional multiplanar sonography. Part 2: application of nomograms to fetuses with posterior fossa malformations

Abstract

Objectives To apply fetal midbrain (MB) and hindbrain (HB) nomograms, developed using three-dimensional multiplanar sonographic reconstruction (3D-MPR) in the mid-sagittal cranial plane, to fetuses with known posterior fossa malformations. Methods, persistent Blake's pouch cyst (n = 6) and megacisterna magna (n = 6). In each case and for each subgroup, the MB-HB biometric parameters and their z-scores were evaluated with reference to our new nomograms. Results The new MB-HB nomograms were able to identify the brainstem and vermian anomalies and differentiate fetuses with MB-HB malformations from

Fourth ventricle index: sonographic marker for severe fetal vermian dysgenesis/agenesis

“…Qualitative assessment requires observation of the cerebellar 'butterfly-shaped' structure and the CM 6-8 . However, examination of the 4V has not yet been incorporated routinely into this assessment, despite the fact that its normal anatomic features have been described and its morphological assessment is known to be important for the characterization of MB-HB anomalies 3,5,9,10,14,16 . Bronshtein et al 13 described the normal 4V as having an APD < 2 / 3 of the cerebellar AP diameter and a width < 1 / 2 of the TCD.…”

Assessment of fetal midbrain and hindbrain in mid‐sagittal cranial plane by three‐dimensional multiplanar sonography. Part 1: comparison of new and established nomograms

“…In this study, we present our newly established nomograms for fetal MB and HB parameters in the mid‐sagittal cranial plane assessed by 3D‐MPR. Furthermore, in order to evaluate their accuracy and their ability to diagnose MB and HB malformations, we have applied them to fetuses with established posterior fossa anomalies; these results are provided in a sister paper, in this issue of the Journal.…”

3-D Volume Assessment of the Corpus Callosum and Cerebellar Vermis Using Various Volume Acquisition and Post-Processing Protocols

“…Several studies have shown that selected 3-D volume datasets contain enough anatomic information to evaluate fetal brain anatomy in all three orthogonal planes [2-4, 14, 15, 18, 23]. This approach has been used to identify fetal anomalies [2,7,8]. One collaborative study examining the reliability of 3-D sonography found excellent intercenter agreement in data analysis and the definition of structural CNS anomalies [2].…”