Ultrasonographic evaluation of geniohyoid muscle movement during swallowing: a study on healthy adults of various ages.

Our purpose in this study was to investigate the application of B+M-mode ultrasound (B/M-mode) imaging as a new approach to quantifying activity patterns of the geniohyoid muscles during swallowing and to assess how these patterns differ according to age and gender. Sixty healthy volunteers (30 men, 30 women) were divided into three age groups (20-39, 40-59, 60-79 years). The subjects were then given 10 ml of mineral water. Ultrasonographic imaging was repeated 5 times and measurements were averaged. Simultaneous B/M-mode images were captured at two regions along the lateral geniohyoid muscle wall. All geniohyoid muscle movement was recorded by real-time B/M-mode. In all cases, ultrasonographic images of the geniohyoid muscle movement during swallowing were easily visualized with the use of real-time B/M-mode. The average moving distance and the duration of movement of the geniohyoid muscle during contraction increased gradually with age. There was a significant difference in ultrasonic measurements of the moving distance and the duration of movement during swallowing between males and females in the three age groups (P < 0.05). B/M-mode imaging provides a simple, noninvasive technique for visual assessment of the lateral geniohyoid muscle wall and may provide a clinical method for evaluating swallowing.