Computed tomography and magnetic resonance imaging findings in infants with microcephaly potentially related to congenital Zika virus infection

Abstract

The recent association between the increase in the number of neonates with microcephaly in northeastern Brazil and the outbreak of infection with the Zika virus, which has been occurring in the Americas, has been declared a public health emergency of international concern. The evidence that implicates the virus as the cause of this public health emergency has been demonstrated ever more consistently. This pictorial essay illustrates the imaging characteristics seen on computed tomography and magnetic resonance imaging scans of infants admitted to a rehabilitation hospital with a diagnosis of microcephaly and a maternal history of rash during pregnancy.

Congenital Zika syndrome and neuroimaging findings

“…In conclusion, as presented by Peixoto Filho et al (19) , the neuroimaging aspects of congenital ZIKV syndrome are becoming increasingly more consolidated. It is of fundamental importance for radiologists to have knowledge of those aspects because, although they are not pathognomonic, they can raise the diagnostic suspicion of the syndrome.…”

“…The article authored by Peixoto Filho et al (19) , published in this issue of Radiologia Brasileira, clearly illustrates the main aspects of computed tomography and magnetic resonance imaging of the skulls of children with CNS malformations likely related to ZIKV infection. In that article, nine children were examined and the main imaging aspects were as follows: microcephaly; occipital protuberance with excessive scalp skin; reduced volume of the cerebral parenchyma, with gyral simplification; ventriculomegaly; parenchymal calcifications, predominantly located at the cortico-subcortical junction, agenesis/dysgenesis of the corpus callosum, and changes in the posterior fossa, such as cerebellar and pontine hypoplasia.…”

What We Can Find Beyond the Classic Neuroimaging Findings of Congenital Zika Virus Syndrome?

“…Unlike the classic TORCH infections Eur Neurol 2020;83:17-24 DOI: 10.1159/000505834 (toxoplasmosis, other agents [e.g., HIV, syphilis] rubella, cytomegalovirus, and herpes simplex), in which calcifications are periventricular and cortical, ZIKV involvement tends to appear with cortical-subcortical transition, leading to the suggestion that it has a vascular infection component, as other processes that affect mainly this region are associated with vascular alterations [21,[24][25][26][27][28][29][30][31][32]. The infratentorial region is the least common site of involvement, affected in only 4-18% of cases; calcifications are seen more frequently in the basal nuclei/thalamus (29-65%), periventricular region (14-65%), and cortical region (14-24%) [21,[24][25][26][27][28][29][33][34][35]. According to Oliveira-Szejnfeld et al [21], infratentorial calcifications are present in more severe cases associated with brainstem dysmorphia, aqueduct stenosis, and secondary hydrocephalus.…”

“…They are characterized by a sharp, atrophic, encephalic trunk with preferential bridge involvement ( Fig. 1), commonly related to greater disease severity and possibly related to a reduction in the number of descending fibers and direct viral damage [21,[24][25][26][27][28][29][30][31][32][33][34][35]. Other posterior fossa abnormalities include cerebellar hypoplasia (Fig.…”

“…Other posterior fossa abnormalities include cerebellar hypoplasia (Fig. 2), which is usually diffuse and symmetrical and occurs in 27-82% of cases, and mega cisterna magna, which is related to greater disease severity; no direct relationship between these 2 manifestations has been established [21,[24][25][26][27][28][29][30][31][32][33][34][35]. Aragão et al [31] reported that the presence of arthrogryposis was related to more severe brain damage, with a greater chance of cerebellar and cerebellum hypoplasia.…”