Zika Virus Congenital Microcephaly Severity Classification and the Association of Severity with Neuropsychomotor Development

Abstract

<jats:p>Objectives: We propose and evaluate a system for assessing severity of ZikV-related microcephaly brain abnormalities called RaRe (Radiological Reading score). The system is a combination of neuroradiologist evaluation scores; we also propose and evaluate its semi-automated version, which is generated from MRI indices. Design: We carried out a cross-sectional study with retrospective data collection at birth and 13-39 months; data collection includes radiologists evaluation of MRI images and a semi-automated system for analyzing MRI images from ZikV-related microcephaly patients; we also evaluated the association of severity and RaRe scores with developmental outcomes. Setting: Brain Institute of Rio Grande do Sul and Memorial Hospital Arthur Ramos, both in Brazil. Participants: 42 infants with ZikV-related congenital microcephaly (age at second evaluation M = 24.83 months; SD = 5.82). Mothers were infected by Zika Virus during pregnancy and were symptomatic or asymptomatic. Main outcome measures: Clinical and radiological outcomes (blindly reviewed); severity classification system (semi-automated - RaRe-Auto or based on neuroradiological evaluation - RaRe-Clin) and association with developmental outcomes (Bayley-III scales). Results: RaRe-Clin positively correlated with RaRe-Auto (r = 0.892; p &lt; 0.001). Severity negatively associated with neurodevelopment scores assessed by Bayley-III scales in all three domains: cognition, language and motor skills. There was no association between trimester of infection and head circumference at birth (r = 0.160; p = 0.338) but there was an association between trimester of infection and RaRe-Clin (r = -0.355; p = 0.029). Conclusions: The clinical and semi-automated RaRe scores predicted Bayley scores. RaRe-Clin and RaRe-Auto can predict the trimester of infection and severity of outcomes and should be investigated in their further application with other congenital and infection-related brain abnormalities.</jats:p>