Dissociated deviation.: A strabismus of cortical origin

Background: We undertook this study to determine the cortical alterations related to the origin of dissociated deviation. Methods: This was a prospective, descriptive and observational study that included 10 children with diagnosis of dissociated horizontal deviation, without previous evidence of neuronal damage. Manual, cerebral and ocular dominance were determined, as well as sensorial state and visual perceptual profile. Cortical response to different stimuli was analyzed: luminous, hyperventilation, slow and saccadic movements of pursuit, gaze and stare through cerebral mapping and neurometric EEG. The biochemical composition to the visual cortex by means of magnetic resonance spectroscopy was also investigated. Results: The following alterations were demonstrated: a) neuroelectric: dysynchronic, paroxysms and/or lentification; b) neurometabolic: elevation of lactate, decrease of N-acetylaspartate and loss of the creatine/choline relationship; c) sensorial: suppression and amblyopia; d) perceptual vision: underyield in visual abilities; e) motor: horizontal and vertical dissociated deviation; f) optometric: hyperopic astigmatism. Conclusions: The study suggests that dissociated deviation has a cortical origin and is related to epileptogenic disease.