New Zika Research to be Presented at RSNA 2016
Three new studies reporting on the effects of the Zika virus outbreak in Brazil will be presented next week at the RSNA annual meeting in Chicago.
The first study looks at CT findings of the central nervous system in 16 newborns with congenital Zika virus infection confirmed by tests in cerebral spinal fluid. The researchers found a pattern of tomographic findings in the central nervous system associated with the microcephaly outbreak that suggest a new etiology.
Natacha Calheiros de Lima Petribu, MD, from the Department of Radiology at Barão de Lucena Hospital in Pernambuco, Brazil, and colleagues concluded that although etiopathogenesis and associated risk factors have not yet been well established, the data strongly suggest that the Zika virus can cause microcephaly.
“In the face of the increase of microcephaly cases and the possibility of global dissemination of the Zika virus, it’s necessary to recognize these radiologic findings,” the authors write.
In another study, researchers performed a prospective study of seven pregnant patients with the Zika virus infection at different gestational ages. They were subjected to ultrasound (US) and fetal MRI. After birth, the researchers performed transfontanellar US, CT and MRI of the head with posterior 3-D reconstructions of the skull for the newborns.
They found more than half the newborns had microcephaly with almost complete agyria, hydrocephalus, and multifocal dystrophic calcifications in the cortex and subcortical white matter, with associated cortical displacement.
Bianca Guedes Ribeiro, MD, from the Department of Radiology at Clínica de Diagnóstico por Imagem in Rio de Janeiro, and colleagues also found perinatal imaging by MRI and CT scan enabled diagnosis of pachygyria, corpus callosum dysgenesis, and small anterior fontanel with premature closure of cranial sutures.
“All of these aspects are seen in the majority of the intrauterine Zika virus infection with central nervous system involvement and it can be considered on diagnosis criteria,” the authors write.
A third study analyzed the imaging results of three target groups affected by Zika: adults who developed acute neurological syndrome, newborns with vertical infection with neurological disorders and pregnant women with rash outbreaks suggestive of Zika.
Cristina A. Fontes, MD, from the Department of Radiology at Antonio Pedro University Hospital – Federal Fluminense University in Rio de Janeiro, and colleagues found most adult patients presented with symptoms of Guillain-Barré syndrome and variants and a few patients presented with encephalomyelitis. The most common finding was lumbar root enhancement followed by lumbar dorsal ganglia enhancement and facial nerve enhancement.
Other findings included brain stem lesions with high T2-weighted fluid-attenuated inversion recovery (T2/FLAIR) signal, spinal cord lesions with high T2/FLAIR signal and trigeminal nerve enhancement. In newborns, MRI and fetal MRI showed anatomical changes in the brain parenchyma and orbital injuries.
“MRI is a sensitive tool for demonstrating signs of Guillain-Barré syndrome and encephalomyelitis associated with Zika virus. In newborns and fetuses, MRI helped us understand the injuries that occur in the developing brain,” the authors write.