Impairment of Bilateral Vocal Cord Abduction in Corticobasal Degeneration: A Case Report

<p>Corticobasal degeneration (CBD) is a rare neurological disease in which parts of the brain deteriorate or degenerate. The initial symptoms of CBD are stiffness, shakiness, and slowness in either upper or lower extremities. Other initial symptoms include dysphagia, dysarthria, and difficulty in controlling the muscles of the face and mouth.</p><p>We report the case of a 72-year-old female with CBD and impairment of bilateral vocal cord abduction who had a gastrostomy tube due to a diagnosis of aspiration pneumonia 2 years ago. Her family complained of difficulty in deglutition, therefore we started intervention for evaluating swallowing function in March 2011. We confirmed that she could ingest some jelly without aspiration, so she was followed up every 2 or 3 months. Her dysphagia developed slowly, and the silent aspiration appeared.</p><p>In March 2012, her family found that she was frequently holding her breath with the mouth closed during the daytime, and showed cyanosis under care and snoring at night. We evaluated the state of her larynx using an endoscope during the pharyngeal reflex and breathing, and movement was observed. Impairment of the bilateral vocal cord abduction during expiration appeared for 70 seconds. Thus, we decided to stop her oral intake, and prescribed measurement of oxygen saturation during the daytime and at night. It was observed that her oxygen saturation fell rapidly during the early morning and tube feeding. We contacted her family doctor, and informed that the patient might inhale oxygen when her oxygen saturation fell.</p><p>Symptoms of impaired vocal cord abduction without atrophy of the cricoarytenoid muscle are seen in Parkinson's disease and progressive supranuclear palsy, however, it is unknown for CBD patients. The potential for vocal cord abduction was preserved, and impairment of the bilateral vocal cord abduction was caused by abnormal constriction of some muscles of the larynx. Episodes of respiration difficulty occurred with the progression of dysphagia. Although the occurrence of vocal cord abduction is rare in CBD, we should pay attention to detect this symptom when evaluating swallowing function.</p>