Sweep visually evoked potentials and visual findings in children with West syndrome.
BACKGROUND
West syndrome (WS) is a type of early childhood epilepsy characterized by progressive neurological development deterioration that includes vision.


AIM
To demonstrate the clinical importance of grating visual acuity thresholds (GVA) measurement by sweep visually evoked potentials technique (sweep-VEP) as a reliable tool for evaluation of the visual cortex status in WS children.


METHODS
This is a retrospective study of the best-corrected binocular GVA and ophthalmological features of WS children referred for the Laboratory of Clinical Electrophysiology of Vision of UNIFESP from 1998 to 2012 (Committee on Ethics in Research of UNIFESP n° 0349/08). The GVA deficit was calculated by subtracting binocular GVA score (logMAR units) of each patient from the median values of age norms from our own lab and classified as mild (0.1-0.39 logMAR), moderate (0.40-0.80 logMAR) or severe (>0.81 logMAR). Associated ophthalmological features were also described.


RESULTS
Data from 30 WS children (age from 6 to 108 months, median = 14.5 months, mean ± SD = 22.0 ± 22.1 months; 19 male) were analyzed. The majority presented severe GVA deficit (0.15-1.44 logMAR; mean ± SD = 0.82 ± 0.32 logMAR; median = 0.82 logMAR), poor visual behavior, high prevalence of strabismus and great variability in ocular positioning. The GVA deficit did not vary according to gender (P = .8022), WS type (P = .908), birth age (P = .2881), perinatal oxygenation (P = .7692), visual behavior (P = .8789), ocular motility (P = .1821), nystagmus (P = .2868), risk of drug-induced retinopathy (P = .4632) and participation in early visual stimulation therapy (P = .9010).


CONCLUSIONS
The sweep-VEP technique is a reliable tool to classify visual system impairment in WS children, in agreement with the poor visual behavior exhibited by them.
['de Freitas Dotto|Patrícia|P|', 'Cavascan|Nívea Nunes|NN|', 'Berezovsky|Adriana|A|', 'Sacai|Paula Yuri|PY|', 'Rocha|Daniel Martins|DM|', 'Pereira|Josenilson Martins|JM|', 'Salomão|Solange Rios|SR|']
D002648:Child D002675:Child, Preschool D005074:Evoked Potentials, Visual D005260:Female D006801:Humans D007223:Infant D008297:Male D012189:Retrospective Studies D013036:Spasms, Infantile D014793:Visual Cortex
Sweep visual evoked potentials West syndrome Childhood epilepsy Grating visual acuity Strabismus Nystagmus Cortical visual impairment