Quantitative classification of pediatric swallowing through accelerometry

Background: dysphagia or swallowing disorder negatively impacts a child's health and development. the gold standard of dysphagia detection is videofluoroscopy which exposes the child to ionizing radiation,and requires specialized clinical expertise and expensive institutionally-based equipment,precluding day-to-day and repeated assessment of fluctuating swallowing function. swallowing accelerometry is the non-invasive measurement of cervical vibrations during swallowing and may provide a portable and cost-effective bedside alternative. in particular,dual-axis swallowing accelerometry has demonstrated screening potential in older persons with neurogenic dysphagia,but the technique has not been evaluated in the pediatric population. methods: in this study,dual-axis accelerometric signals were collected simultaneous to videofluoroscopic records from 29 pediatric participants (age 6.8 ± 4.8 years; 20 males) previously diagnosed with neurogenic dysphagia. participants swallowed 3-5 sips of barium-coated boluses of different consistencies (normally,from thick puree to thin liquid) by spoon or bottle. videofluoroscopic records were reviewed retrospectively by a clinical expert to extract swallow timings and ratings. the dual-axis acceleration signals corresponding to each identified swallow were pre-processed,segmented and trimmed prior to feature extraction from time,frequency,time-frequency and information theoretic domains. feature space dimensionality was reduced via principal components. results: using 8-fold cross-validation,16-17 dimensions and a support vector machine classifier with an rbf kernel,an adjusted accuracy of 89.6% ± 0.9 was achieved for the discrimination between swallows with and with out airway entry. conclusions: our results suggest that dual-axis accelerometry has merit in the non-invasive detection of unsafe swallows in children and deserves further consideration as a pediatric medical device. © 2012 mérey et al; licensee biomed central ltd.