Visual Function in Infants with West Syndrome: Correlation with EEG Patterns

Abstract

Summary:Purpose: Several studies have reported behavioral and electrophysiological evidence of visual impairment during the active stage of West syndrome. The underlying mechanisms are, however, poorly understood, and little has been reported about the correlation between visual impairment, EEG patterns, and brain lesions. The aim of the study was to assess visual function at the onset of spasm and 2 months thereafter and relate visual findings to brain lesions and EEG features.Methods: Twenty-five infants with West syndrome were enrolled and studied with (a) a full clinical assessment including a battery of tests specifically designed to assess visual function, (b) a video-polygraphic study, and (c) brain magnetic resonance imaging (MRI). Besides brain neuroimaging and EEG comparison with visual function, an intra-EEG analysis was performed to investigate the possible relation of EEG patterns to fluctuating visual behavior (fixation and following).Results: Twenty-two children had at least one abnormal result on one or more of the tests assessing visual function at T 0 . Visual impairment at the spasm onset was related to the sleep disorganization rather than to the hypsarrhythmic pattern in awake EEG. After 2 months, both EEG features become significantly linked to visual function. Visual function improved in several cases after 2 months, in parallel with the seizure regression. No relation was found between EEG patterns and fluctuating visual behavior.Conclusions: The study supplies new evidence of the involvement of visual function in West syndrome. The presence of abnormal visual findings in infants without lesions on brain MRI suggests that visual abnormalities are due not only to brain injury but also to epileptic disorder per se. New insight is also provided into the possible mechanisms underlying clinical and EEG abnormalities.

Visual development in infants with prenatal post-haemorrhagic ventricular dilatation

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Visual Field Loss in Patients with Refractory Partial Epilepsy Treated with Vigabatrin

“…However, the lower apparent prevalence in these two studies may merely reflect the difficulty in assessing visual field loss in children. The situation is also complicated by possible underlying ocular and visual abnormalities in children with infantile spasms, [19,20] a frequent indication for vigabatrin therapy. However, no study has been undertaken that directly compares the frequency of VAVFL between children and adults.…”

Neuropsychological Deficits in Childhood Epilepsy Syndromes

“…Impaired eye-hand coordination was found to be deficient when infants were evaluated, even in idiopathic patients who appear to be functioning normally otherwise (Rando et al 2005). Impaired visual functioning involving acuity, ocular motility, visual field, visual attention, and visual scanning skills have been found in several studies with infants (Guzzetta et al 2002;Rando et al 2004). Guzzetta (2006) reported an associated deficit in auditory attention, and visual and auditory functions were both correlated with cognitive competence on the Griffith Scales of Infant Development.…”