Study Found Brain Abnormalities in Fetuses Exposed to Zika Essay
LAS VEGAS (Jan. 23, 2017)—In a study to be presented Friday, Jan. 27, in the oral concurrent session at 1:15 p.m. PST, at the Society for Maternal-Fetal Medicine’s annual meeting, The Pregnancy Meeting™, researchers with the Baylor College of Medicine Department of Obstetrics and Gynecology, Houston, Texas partnered with the Maternal-Fetal Unit, CEDIFETAL, Centro de Diagnostico de Ultrasonido e Imagenes, CEDIUL, Barranquilla, Columbia and the Unidad De Fertildad Y Genetica De Cartagena, Cartagena de Indias, Columbia, to create the study, Characterization of brain malformations and volume assessment in fetuses with Zika Virus infection using MRI.
Researchers assessed fetal brain findings and volumetric composition with magnetic resonance imaging (MRI) of confirmed Zika virus infected fetuses from the recent outbreak in Barranquilla, Columbia. The fetuses were screened throughout gestation, finding brian anomalies at 29 weeks gestation.
“Up until our study, there have not been any reports focused on detailed brain imaging from the Zika outbreak in Colombia,” stated Magdalena Sanz-Cortes, M.D., Ph.D. with Baylor College of Medicine’s department of obstetrics and gynecology, maternal-fetal medicine specialist at Texas Children’s Pavilion for Women and presenter of the study at the SMFM annual meeting. The researchers found a reduction in brain tissue and increased amount of fluid that was most pronounced in the upper brain. “Microcephaly does not happen in all Zika cases,” Sanz-Cortes explained, referring to the small head size that has been characterized as a Zika symptom. The findings were similar to the findings of infected babies in Brazil.
“This research has filled a gap of knowledge for us,” Sanz-Cortes continued, “these results support the recent notion that we should not rely on microcephaly to determine if a fetus or newborn has contracted the Zika Virus.”
Abstract 73 Characterization of brain malformations and volume assessment in fetuses with zika virus infection using MRI
Magdalena Sanz-Cortes¹ , Alexander J. Zarutskie¹ , Mayel Yepez¹ , Anna Maria Rivera² , Isreal Diaz Yunes³, Arun Mahadev¹ , Anil Shetty¹ , Wesley Lee¹ , Michael Belfort¹ , Kjersti Aagaard¹ , Guido Parra² , Miguel Parra Saavedra² ¹Baylor College of Medicine Department of Obstetrics and Gynecology, Houston, TX, ²Maternal-Fetal Unit, CEDIFETAL, Centro de Diagnóstico de Ultrasonido e Imágenes, CEDIUL, Barranquilla, Colombia, ³Unidad De Fertilidad Y Genetica De Cartagena, Cartagena de Indias, Colombia
OBJECTIVE: To assess fetal brain findings and volumetric composition with MRI in a prospective cohort of confirmed Zika virus (ZIKV) infected fetuses from the current outbreak in Barranquilla, Colombia.
STUDY DESIGN: Between December 2015 and July 2016, 214 pregnant patients with suspected symptomatic ZIKV exposure (and their sexual partner/s) were included. Cases with fetal brain anomalies on ultrasound(US) and confirmed ZIKV (by qRT-PCR) underwent a fetal MRI (1.5 T Phillips Ingenia). In order to create a single 3D volume absent of artifact from inherent motion and intensity corruption, a super-resolution (SR) reconstruction was obtained by coregistering the 3 orthogonal T2 weighted image stacks and iteratively performing voxel-based intensity matching. SR images were postprocessed for volumetric analyses by performing manual segmentation. Total Brain Volume (TBV), supratentorial brain parenchyma (SBP), ventricular volume (VV), brainstem volume (BV), cerebellar volume (CV), and total intracranial volume (TICV) (TBV + volume of CSF in the subarachnoid space) were determined.
RESULTS: A total of 13 cases presented with abnormal brain US findings (microcephaly, ventriculomegaly, callosal dysgenesis, calci- fications and cortical anomalies). Seven of those cases that were ZIKV positive underwent a fetal MRI (29.0+4.4 weeks), and were gestational age matched to 7 healthy controls (CTRLS) (29.87+4.61 weeks; p=0.72). ZIKV infected fetuses significantly differed from controls in TBV (ZIKV: 9422.42+2169.11 vs. CTRLS: 20529.7+7049.95; p<0.01) and TICV (16390.42+3690.41 vs. 35593.42+12281.71; p<0.01). No significant difference was seen in VV (2692.85+540.92 vs. 2967.14+759.74; p=0.45), BV (653.01+211.51 vs. 990.22+369.31; p=0.06) or CV (914.31+414.57 vs. 1416.14+565.85; p=0.08). The CSF/SBP ratio was higher (1.36+0.20 vs. 0.99+0.16; p<0.01) in Zika affected fetuses suggesting microencephaly.
CONCLUSION: In this large cohort of ZIKV infected gravidae, we characterized brain findings using MRI. Microcephaly, callosal dysgenesis, ventriculomegaly and calcifications are common anomalies associated with fetal ZIKV. We observed a significant association between decreased brain volumes (predominantly evidenced by decreased SBP and increased CSF in the subarachnoid space) and ultrasound detected microcephaly.