An Exploratory Study of Hyoid Visibility, Position, and Swallowing-Related Displacement in a Pediatric Population.

Hyoid position and swallowing-related displacement has been studied in healthy adults and adults with dysphagia, but research is limited in children. The aim of this study was to investigate feasibility of visualizing and measuring position and swallowing-related displacement of the hyoid bone in children. We explored relationships between hyoid displacement, age and aspiration risk scores. Pediatric swallowing data were extracted from a videofluoroscopy database containing recordings from 133 children aged 9 days to 21 years (mean 36 months, SD 3 years) referred for videofluoroscopy due to concerns regarding their feeding. Children presented with varying etiologies: neurological, structural, respiratory, and other diagnoses. Still shot images were extracted for the frame of hyoid peak position and a frame showing the hyoid at rest. Pixel-based image analysis software was used to measure hyoid position in three directions (X = anterior, Y = superior, XY = hypotenuse) relative to C4 vertebra. Difference between rest and peak position was used to measure hyoid displacement (X, Y and XY). The hyoid was not visible in children < 9 months, but could be reliably visualized and measured in 49 children. Descriptive statistics were collected for hyoid parameters. Age was significantly associated with rest (Y and XY) and peak (Y and XY) hyoid position parameters as well as anterior displacement. No significant associations were observed between hyoid parameters and aspiration risk scores. This study successfully explored hyoid visibility, position and swallowing-related displacement in a pediatric population. Hyoid can be reliably visualized and tracked through videofluoroscopy in children > 9 months of age.