The Impact of Periventricular Leukoaraiosis in Post-stroke Oropharyngeal Dysphagia: A Swallowing Biomechanics and MRI-Based Study

Oropharyngeal dysphagia is a highly prevalent post-stroke complication commonly associated with topographically specific gray-matter damage. In contrast, the role of damage to the extensive white matter brain network (leukoaraiosis) in post-stroke oropharyngeal dysphagia has not yet been clarified. We aim to assess the role of leukoaraiosis in post-stroke oropharyngeal dysphagia. We designed a cross-sectional study and retrospectively collected from our database patients with dysphagia affected by a recent stroke and on whom both a brain 1.5 T-MRI and a videofluoroscopy had been performed. Leukoaraiosis was assessed in brainstem and in cerebral regions (periventricular or deep) with Fazekas scale. Penetration-Aspiration-Scale and time to laryngeal vestibule closure and to upper esophageal sphincter opening were analyzed. Study population (n = 121; 57% men, 75.5 ± 9.4y) presented mostly supratentorial ischemic PACI-type strokes. Of the patients, 86% had unsafe swallows (PAS = 3.97 ± 2.04); 94.2% had cerebral leukoaraiosis (Fazekas = 3.36 ± 1.7) and 42.1% had brainstem-leukoaraiosis, hypertension being the main risk factor. We found both significant positive associations between degree of periventricular-leukoaraiosis and total-leukoaraiosis and presence of risk of aspirations (p = 0.016 and p = 0.023, respectively); and a correlation between periventricular-leukoaraiosis and PAS scale severity (r = 0.179, p = 0.049). No correlations/associations were found between stroke volume and dysphagia in this study. Our study supports a role for leukoaraiosis in the pathophysiology of dysphagia. Stroke is associated with chronic short-connection/circuit injury and damage to periventricular white matter long connections is a relevant neuro-pathophysiological mechanism contributing to impaired safety of swallow in post-stroke oropharyngeal dysphagia patients.