[Fetal transcerebellar diameter measured in screening ultrasound: Feasibility and reproducibility]

Abstract

Objective: The aim of the study was to evaluate feasibility and reproducibility of fetal transcerebellar diameter measurement during second and third trimester ultrasound mass screening by junior and senior physicians.

Materials and methods: A monocentric prospective study was conducted at the tertiary care teaching hospital in Lyon, including patients undergoing their second or third trimester planned ultrasound exam. For each patient, a resident and a senior practitioner measured each fetal transcerebellar diameter, during a blinded experiment, according to the transcerebellar plane described by the International Society of Ultrasound in Obstetrics and Gynecology. Images have been scored on 4 criteria. The inter-observer variability for transcerebellar diameter and image quality was assessed using an intra-class correlation coefficient. Image quality has been analyzed according to pregnancy term and to fetal presentation.

Results: Sixty-six patients were included, 44 patients before and 22 patients after 30 weeks. Inter-observer variability of transcerebellar diameter measurement was 0.4%. Inter-observer variability of image quality was 13.5%. Image quality was not significantly different between seniors and residents (P=0.06). Gestational age and fetal presentation did not affect significantly image quality (P=0.42) and (P=0.64) respectively.

Conclusion: Transcerebellar diameter measurement during mass screening is simple and reliable. Posterior fossa abnormalities can be explored through its measurement.

Keywords: Biometry and fetal malformation; Biométrie; Cerebellum; Cervelet; Fosse cérébrale postérieure; Malformation fœtale; Posterior fossa.