Abstract:

Objective： To investigate changes of swallowing function and associated symptoms in Chiari malformation typeⅠ (CMⅠ) patients with and without dysphagia by the analysis of their clinical and high-resolution manometry (HRM) parameters. Methods: A total of 42 patients diagnosed with symptomatic CMI without atlantoaxial dislocations which were confirmed by clinical manifestations and magne-tic resonance imaging(MRI) findings between January 2010 and July 2015 at Peking University Third Hospital were included in this study. Twenty patients had a history of various dysphagia symptoms, or reported symptoms of choking, coughing after eating or drinking, while the other 22 patients denied symptoms of dysphagia. The data collected from the medical records of these patients included the patient’s age, sex, date of diagnosis, duration of illness, symptoms, results of MRI and HRM, and date of sur-gery. Results: (1) Dysphagia group had 14 female patients, and no-dysphagia group had 8 female patients. Dysphagia usually occurred in female patients, and in addition to dysphagia, we recorded other symptoms and signs in the CMⅠ patients, including numbness, hypoesthesia, limb weakness, neck pain, muscle atrophy, ataxia, hoarseness, symptoms caused by posterior cranial nerve damage, pharyngeal reflex, uvula deviation, and pyramidal signs. A higher percentage of the CMⅠ patients with dysphagia (15/20) had symptoms of posterior cranial nerve damage compared with the control group (5/22; P=0.01). (2)HRM showed a significant difference in upper esophageal sphincter (UES) relax ratio measurement (75.3% vs. 63.1%, P=0.023) and UES proximal margin (17.2 cm vs. 15.7 cm, P=0.005) between the two groups. (3) The percentage of syringomyelia affecting the bulbar or upper cervical region on MRI was significantly higher in the dysphagia group (17/20 vs. 7/22, P=0.001). Conclusion: CMⅠ was usually accompanied by symptoms caused by posterior cranial nerve damage, ataxia, and positive pyramidal signs. Location of the syringomyelia affecting specifically the bulbar or upper cervical region was associated with dysphagia in CMⅠ patients. These findings suggest that the mechanism of dysphagia in CMⅠ may be due to a dysfunction in the neurological pathway of pharyngeal muscle movement. Dysphagia etiology work-up should include CMⅠ in the differential diagnosis.

Key words: Dysphagia, Chiari malformation typeⅠ, High-resolution manometry