Ultrasound detects more Zika-related brain injuries in infants than MRI

Prenatal and postnatal ultrasonography alone—compared to combining the modality with MRI—was found to detect the most abnormal cases of Zika virus-related brain injury in infants and unborn fetuses, according to new research published online Nov. 26 in JAMA Pediatrics.  

For the study, Sarah B. Mulkey, MD, PhD, of the Division of Fetal and Translational Medicine at the Children’s National Health System in Washington, D.C., and colleagues enrolled 82 pregnant women with Zika infection from June 15, 2016 through June 17, 2017. Of the women, 80 were from Columbia and two were from the U.S.  

The women received MRI and ultrasound exams during their second and/or third trimesters. After giving birth, the infants underwent brain MRI and cranial ultrasound and had blood samples tested for the infection.  

Three cases (four percent) of severe fetal brain abnormalities were detected by MRI, in which two of these cases had abnormal ultrasound results.  

In newborns, cranial ultrasonography and brain MRI revealed new mild findings of the congenital Zika infection in 23 of 61 infants.

“For most of our cases, fetal MRI did not add value beyond ultrasound; most of our cases had normal fetal MRI findings and, for pregnant women and their families, MRI provided additional reassurance,” the researchers wrote. “Therefore, normal fetal imaging had predictive associations with normal postnatal imaging or mild postnatal imaging findings unlikely to be of significant clinical consequence.”