[Subclinical swallowing disorder in patients with abnormal sensation in the throat].

Measurement of swallowing pressure was done in 75 patients who complained of abnormal sensation such as obstructive sensation, difficulty in swallowing, etc. in the throat without noticeable cause. Abnormal swallowing pressure curves were observed in 33 patients (44%), and 76% of them showed abnormal elevation of the pressure at the hypopharyngeal or cervical esophageal region. These results indicated that subclinical swallowing disorder, particularly abnormal high swallowing pressure, can be a possible cause of their complaints. The author assumed that abnormal elevation of swallowing pressure is due to hypertonicity of the hypopharyngeal and cervical esophageal muscles. By the animal experiments using dog, a muscle relaxant, eperizone hydrochloride, revealed to change muscle tonus of the hypopharyngoesophageal muscles. Intravenous administration of the drug decreased swallowing pressure and prolonged the relaxation time of the cricopharyngeal muscle. Clinically the muscle relaxant showed to be effective in ameliorating the complaint of the patients with abnormal high swallowing pressure at the hypopharyngeal or cervical esophageal region. Based on the above results, the author proposed that the clinical entity, hypopharyngeal-cervical esophageal hypertonicity, causes a subclinical swallowing disorder leading to the abnormal sensation in the throat.