Videofluoroscopic assessment of pharyngeal stage delay reflects pathophysiology after brain infarction

Abstract

The pathophysiology of dysphagia caused by brain infarction varies with the site of the lesion in the brain. Patients with suprabulbar lesions have demonstrated delayed triggering of pharyngeal stage including delayed laryngeal elevation. Patients with severe pharyngeal stage delay have a high risk of intractable aspiration to the lower respiratory tract. Despite this, few studies have compared the pharyngeal stage delay with the lesion site. We defined a new temporal parameter of the pharyngeal stage delay to assess laryngeal elevation delay against the bolus inflow into the pharyngeal space. This study aimed to elucidate whether this parameter of pharyngeal stage delay is clinically useful to assess the pathophysiology of brain lesions after brain infarction. Case-control study. Videofluoroscopic assessment of swallowing examinations was performed from January 7, 2000 to March 29, 2011 at Kyushu University Hospital. We evaluated the pharyngeal stage delay using motion analysis on videofluoroscopic swallowing examination in patients with normal swallowing and brain infarction patients divided into pathophysiologic lesion groups. Laryngeal elevation delay time and pharyngeal delay time were analyzed. Significant differences in laryngeal elevation delay time were observed between each pathophysiologic lesion group. However, pharyngeal delay time remained similar among groups. Brain infarctions of corticobulbar tract and basal ganglion were significantly associated with laryngeal elevation delay time prolongation. Laryngeal elevation delay time with low-viscosity contrast medium is a recommended parameter to discriminate the corticobulbar tract and the basal ganglion lesion.