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Updated: Nov 4, 2025
Stimulus-specific Cortical Visual Evoked Potential Morphological Patterns
Published on: May 12, 2019
Pattern-Reversal Visual Evoked Potential in Children With Congenital Zika Syndrome
Insights
Children with congenital Zika syndrome often show abnormal pattern-reversal visual evoked potentials (PR-VEP), indicating visual impairment. PR-VEP results were linked to visual acuity but not head size or eye exam findings.
Area of Science:
- Ophthalmology
- Neuroscience
- Pediatrics
Background:
- Congenital Zika syndrome (CZS) is a severe condition affecting infants exposed to the Zika virus in utero.
- Visual dysfunction is a common but not fully characterized manifestation of CZS.
- Objective assessment of visual pathways is crucial for understanding the impact of CZS.
Purpose of the Study:
- To objectively evaluate visual function in children with CZS.
- To utilize pattern-reversal visual evoked potential (PR-VEP) for assessing visual pathways.
- To correlate PR-VEP findings with clinical parameters in CZS.
Main Methods:
- Cross-sectional study comparing CZS children (18-24 months) with age-matched healthy controls.
- Comprehensive ophthalmologic examination and binocular PR-VEP with 60' arc stimuli.
- Correlation analysis of P100 peak time with visual acuity, birth cephalic perimeter, and funduscopic findings.
Main Results:
- PR-VEP was abnormal in 75.6% of CZS children (prolonged latency or no response).
- Significant correlation found between visual acuity and P100 peak time (P < .001).
- PR-VEP abnormalities persisted even without visible funduscopic changes or severe microcephaly.
Conclusions:
- Children with CZS exhibit characteristic PR-VEP abnormalities, suggesting cortical visual impairment.
- PR-VEP is a valuable tool for diagnosing visual dysfunction in CZS, independent of funduscopic findings.
- Visual pathway dysfunction is a key feature of congenital Zika syndrome.
Purpose:
To objectively evaluate the visual function in children with congenital Zika syndrome using pattern-reversal visual evoked potential (PR-VEP).
Methods:
This was a cross-sectional study composed of two patient groups: children aged between 18 and 24 months who were positive for the Zika virus (congenital Zika syndrome group) and age-matched healthy children (control group). All patients underwent a comprehensive ophthalmologic examination and PR-VEP was performed binocularly in a room with constant dim illumination. The P100 peak time in the 60' arc stimuli was used, and the results were correlated with visual acuity, cephalic perimeter at birth, and funduscopic findings.
Results:
Thirty-seven children were included in the congenital Zika syndrome group and 15 in the control group. The mean age was 18.5 ± 0.9 months (range: 17 to 20 months) in the congenital Zika syndrome group and 24.3 ± 1.6 months (range: 21 to 28 months) in the control group. The P100 response was normal in 7 patients (18.9%) with congenital Zika syndrome, borderline in 2 (5.4%), abnormal with prolonged latency in 18 (48.6%), and abnormal with no response in 10 (27.0%). A significant correlation between the visual acuity and P100 peak time was observed (P < .001). The P100 values were not correlated significantly with the cephalic perimeter at birth (P = .412) or the funduscopic findings (P = .510). PR-VEP in children with congenital Zika syndrome and no funduscopic findings was significantly worse than in the control group (P = .001).
Conclusions:
Children with congenital Zika syndrome have characteristically abnormal PR-VEPs regardless of the funduscopic findings and severe microcephaly. The PR-VEP findings supported the diagnosis of cortical visual impairment in these children. [.
