片側声帯麻ひにおける誤えんのメカニズム 特に梨状陥凹部の機能に関して

Abstract

The pathogenetic mechanism of aspiration accompanying unilateral vocal cord paralysis was assessed from the function of the piriform sinuses examined by fluoroscopy and manometry in 31 patients who complained of subjective swallowing difficulty and/or aspiration. The types of aspiration and pharyngeal clearance was determined by fluoroscopy. Swallowing pressures were measured simultaneously in the esophageal inlet, the piriform sinus on the paralyzed side, the vallecula and the oropharynx and compared with the corresponding pressures in normal subjects. The swallowing pressure in the piriform sinus on the unaffected side was measured when possible and compared with the pressure in the piriform sinus on the affected side.Fluoroscopy showed aspiration in 20 patients. Two (10%) showed aspiration in the elevating phase of laryngeal movement, 11(55%) in the falling phase, 7 (35%) in both phase. Bolus retention in the piriform sinus on the affected side and then in the inflow from the arytenoid into the larynx after swallowing was observed in 18 (90%) of the 20 patients. The swallowing pressure in the piriform sinus on the affected side was significantly decreased in 15 (75%) of the 20 patients with aspiration. Swallowing pressure could be determined in both piriform sinuses of 16 patients. It was significantly lower on the affected side in 14 (88%) of them. Eleven patients without aspiration showed good clearance and no decrease in swallowing pressure on the affected side.These result suggest that the impaired clearance accompanying decreased contraction of the piriform sinus on the affected side is partly responsible for aspiration in patients with unilateral vocal cord paralysis.