Fetal MRI Study on Posterior Fossa Abnormalities

USA: Fetal MRI provides the most accurate diagnosis of suspected abnormalities of the posterior fossa (PF), finds a recent study in the journal Pediatric Neurology. This facilitates pregnancy management decision-making.

"Timing of fetal imaging may impact the accuracy of the diagnosis," wrote the authors.

Anomalies in the posterior fossa can be diagnostic dilemmas during the fetal period. There is a wide variation in the prognosis for different diagnoses of the PF. Sarah D. Schlatterer, Children's National Hospital, Washington, DC, and colleagues, therefore, aimed to:

• Determine whether fetal MRI (feMRI) and prenatal neurology consultation lead to alternate diagnoses for maternal-fetal dyads referred due to concern for a fetal PF anomaly.
• Determine how often the pre- and postnatal diagnoses differed.

For this purpose, the researchers performed a retrospective study of cases referred to the Prenatal Pediatrics Institute at Children's National Hospital from January 2012 to June 2018 due to concern for PF anomaly.

Cases were scored for change in prognosis based upon clinical and feMRI report. Postnatal imaging was compared with prenatal imaging, where available.

Key Findings of the Study

• In total, 180 cases were referred for fetal PF anomalies based on outside obstetric ultrasound, underwent feMRI, and had a neurology consultation. FeMRI and neurology consultation resulted in a change in fetal prognosis in 70% of cases.
• The most common referral diagnosis in our cohort was Dandy-Walker continuum, but it was not often confirmed by feMRI.
• In complex cases, PF diagnosis and prognosis determined by feMRI impacted choices regarding pregnancy management.
• Postnatal imaging was obtained in 57 (47%) live-born infants.
• Fetal and postnatal prognoses were similar in 60% of cases.

"Fetal diagnosis impacts pregnancy management decisions," wrote the authors.

"Fetal-postnatal imaging agreement was 60% overall, highlighting the conundrum of balancing the timing of feMRI to provide the most accurate diagnosis in time to make pregnancy management decisions regarding suspected abnormalities of the posterior fossa."

The study titled, "The Role of Fetal MRI for Suspected Anomalies of the Posterior Fossa," is published in the journal Pediatric Neurology.

DOI: https://www.pedneur.com/article/S0887-8994(21)00002-3/fulltext