Profiling Objective Quantitative Videofluoroscopic Measures of Swallowing in Children

Abstract

Swallowing, as one of the critical life-skills for newborn infants and brain-developing children, is one of the most complex physiological mechanisms involving the upper aerodigestive system. Due to increased survival rates of infants with complex medical etiologies, prematurity, and severe disabilities, the prevalence of infants and children diagnosed with swallowing disorders is rising. Videofluoroscopic study of swallowing (VFSS) provides visualization of oral, pharyngeal, and esophageal phases of swallowing, as well as airway during swallowing. It is one of the most common instrumental swallowing assessment tools. However, the current practice of pediatric VFSS is non-standardized and subjective, both in choice of the administration protocol and in the assessment of recorded images, resulting in limited reliability and credibility. Given that VFSS entails radiation exposure and is an expensive instrumental assessment, we believe it should be optimized to obtain maximal clinically significant information on swallowing biomechanics in children. In this thesis, we obtained objective quantitative VFSS measures in a large cohort of children from 0-21 years (n=553). Our aims were to (1) study the potential of these measures to determine the risk of swallow impairments in children such as penetration-aspiration and post-swallow residue, (2) provide clinicians with threshold scores/ reference values of objective quantitative swallow measures to identify children at risk of swallowing impairments and (3) develop a standard protocol of objective quantitative swallow measures for children, which will aid objective VFSS interpretation in children. We identified vital measures including bolus clearance ratio (BCR), pharyngeal constriction ratio (PCR), total pharyngeal transit time (TPT), coordination of airway closure with bolus transit (BP1AEcl), maximum opening of PES during a swallow (PESmax) and duration to maximum hyoid elevation (Hdur) to describe swallow biomechanics with satisfactory rater-reliability. The protocol for objective interpretation of pediatric VFSS will aid clinicians in describing swallow biomechanics in children. Further, the threshold scores can be used to identify children at risk that will require closer observation and potential intervention before sequelae of swallow impairments are seen. Through utilizing VFSS to its full potential, meaningful comparison of swallowing skills over time and treatment effects can be made and will lead to clinicians offering more individualized treatment for children with swallowing disorders.