Lesion site in unilateral stroke patients with dysphagia.

The purpose of this retrospective study was to elucidate specific lesion sites associated with deglutition disorders by studying unilateral left- and right-hemispheric stroke patients with dysphagia. We reviewed computed tomography and magnetic resonance imaging scans and videofluoroscopic swallow studies of 16 consecutive patients with unilateral ischemic infarcts and dysphagia. Results suggest that unilateral hemispheric lesions may produce dysphagia and that patients with left- and right-hemispheric strokes may have different dysphagia characteristics. Although right-hemispheric lesions were significantly smaller than left-hemispheric lesions, dysphagia seemed to be clinically more significant in patients with right-hemispheric strokes, because a higher incidence of delayed pharyngeal swallow (consistency specific) and pharyngeal stasis was recorded in this population. Cytoarchitectonic lesion mapping showed that the insular cortex was the commonest lesion site, suggesting that the insula may be important in swallowing. A prospective double-blind study in a larger sample of unilateral stroke patients with and without dysphagia is warranted to confirm these preliminary findings.