Enrico Biagioni | PubMed Health

PubMed2005

Cognitive competence at the onset of West syndrome: correlation with EEG patterns and visual function.

The aim of this study was to evaluate cognitive development at the onset of West syndrome (WS) with regard to electroencephalogram (EEG) patterns and visual function. Twenty-five patients (14 males, 11 females) at the onset of spasms (T0) in WS and 2 months later (T1) underwent a full clinical evaluation, including neuroimaging, cognitive assessment, video-EEG, and visual function. Mean age of the patients at spasm onset was 5.9 months (SD 2.5; range 2 to 13mo). Cognitive development, assessed with Griffiths Mental Development Scales (GMDS), was generally impaired at T0 and was significantly related to visual function (p<0.001) at both T0 and T1. In general, there was a specific major impairment in the eye-hand coordination scale of the GMDS which tended to disappear after 2 months in less severe cases. At the onset of spasms, sleep EEG organization seemed to be better related to cognitive abilities than awake hypsarrhythmia. These results support a close link between visual function and cognitive competence in WS and provide additional information to improve the understanding of possible mechanisms underlying cognitive impairment.

Child Development↗

PubMed2004

Visual function in infants with West syndrome: correlation with EEG patterns.

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 T0. 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.

Brain↗