Isolated Dysphagia Caused by Failure of Cricopharyngeal Muscle Relaxation after Left Lateral Medullary Lacunar Infarction: A case report

ABSTRACT

Dysphagia can be caused by various mechanisms such as impaired tongue movement, delayed swallowing reflex, decreased pharyngeal peristalsis, incomplete closure of epiglottis and cricopharyngeal dysfunction. Cricopharyngeal muscle, forming the upper esophageal sphincter, acts as a muscular sling between the pharynx and the esophagus. Normally, it closes constantly at rest and opens during laryngeal elevation through active relaxation on the one hand and passive traction by the antero-cephalad laryngeal movement on the other. If its incoordination or hypertonicity happens, dysphagia can develop. Cricopharyngeal muscle dysfunction is caused by various situations such as neuromuscular diseases, postoperative changes and stroke, particularly after brainstem stroke. We report a case of isolated dysphagia caused by failure of active relaxation of cricopharyngeal muscle without aspiration after left lateral medullary lacunar infarction.