Assessment of Oropharyngeal Dysphagia in Patients With Parkinson Disease: Use of Ultrasonography

OBJECTIVE To compare tongue thickness, the shortest hyoid-thyroid approximation (distance between the hyoid bone and thyroid cartilage), and the time interval between the initiation of tongue movement and the time of the shortest hyoid-thyroid approximation, by using ultrasonography in healthy controls and patients with Parkinson disease (PD). METHODS Healthy controls and PD patients with dysphagia were compared. Ultrasonography was performed 3 times for the evaluation of tongue thickness, the shortest hyoid-thyroid approximation, and the time between the initiation of tongue movement and the shortest hyoid-thyroid approximation. RESULTS A total of 24 healthy controls and 24 PD patients with dysphagia were enrolled. No significant differences were demonstrated between the two groups for the shortest hyoid-thyroid approximation (controls, 1.19±0.34 cm; PD patients, 1.37±0.5 cm; p=0.15) and tongue thickness (controls, 4.42±0.46 cm; PD patients, 4.27±0.51 cm; p=0.3). In contrast, the time to the shortest hyoid-thyroid approximation was significantly different between the two groups (controls, 1.53±0.87 ms; PD patients, 2.4±1.4 ms, p=0.048). CONCLUSION Ultrasonography can be useful in evaluating dysphagia in patients with PD by direct visualization and measurement of the hyoid bone. Moreover, ultrasonography might contribute to a greater understanding of the pathophysiology of dysphagia in PD.