Ultrasound Int Open 2016; 02(04): E124-E128
DOI: 10.1055/s-0042-119952
Original Article
© Georg Thieme Verlag KG Stuttgart · New York

Fetal Cerebellar Vermis Circumference Measured by 2-Dimensional Ultrasound Scan: Reference Range, Feasibility and Reproducibility

M. Spinelli
1   Department of Clinical Research, Prenatal Medicine, Inselspital Bern Universitatsklinik fur Frauenheilkunde, Bern, Switzerland
C. Sica
2   Obstetrics and Gynecology, Private Centre "Diagnostica ecografica e prenatale Aniello Di Meglio s.r.l.", Naples, Italy
L. D. Meglio
2   Obstetrics and Gynecology, Private Centre "Diagnostica ecografica e prenatale Aniello Di Meglio s.r.l.", Naples, Italy
D. Bolla
3   OB/GYN, University of Bern, Bern, Switzerland
L. Raio
3   OB/GYN, University of Bern, Bern, Switzerland
D. Surbek
4   OB & GYN, Inselspital, Bern, Switzerland
› Author Affiliations
Further Information

Publication History

received 12 February 2016

accepted 04 October 2016

Publication Date:
24 November 2016 (online)


Purpose: To provide 2-dimensional ultrasonographic (2D-US) normograms of cerebellar vermis biometry, as well as to evaluate the feasibility and the reproducibility of these measurements in clinical practice.

Materials and Methods: A prospective cross-sectional study of 328 normal singleton pregnancies between 18 and 33 weeks of gestation. Measurements of the fetal cerebellar vermis circumference (VC) in the mid-sagittal plane were performed by both a senior and a junior operator using 2D-US. VC as a function of gestational age (GA) was expressed by regression equations. In 24 fetuses 3-dimensional (3D) reconstructed planes were obtained in order to allow comparisons with 2D-US measurements. The agreement between 2D and 3D measurements and the interobserver variability were assessed by interclass correlation coefficients (ICC).

Results: Satisfactory vermis measurements could be obtained in 89.9% of cases. The VC (constant= − 12.21; slope=2.447; r=0.887, p<0.0001) correlated linearly with GA. A high degree of consistency was observed between 2D and 3D ultrasound measurements (ICC=0.846 95% CI 679–0.930) as well as between measurements obtained by different examiners (ICC=0.890 95% CI 989–0.945).

Conclusion: 2-dimensional ultrasonographic measurements of cerebellar vermis throughout gestation in the mid-sagittal view seem to be feasible and reproducible enough to be potentially used in clinical practice. Such measurements may supply a tool for accurate identification of posterior fossa anomalies, providing the basis for proper counseling and management and of these conditions.