Pharyngoesophageal Segment Distention Across Volumes and Pathology

Purpose Patients receive multiple bolus trials during a videofluoroscopic swallowing study (VFSS) to assess swallow function, inclusive of narrowing within the pharyngoesophageal segment (PES). While differences in the narrowest and widest segments are visualized, the ratio of distention across boluses is not well understood. Method A retrospective review of 50 consecutive VFSSs with five boluses of varied viscosity and volume was performed. Still images at maximal PES distention were captured and scaled using a 19-mm disk. Measurements of the narrowest and widest segments were obtained, and a distention ratio was calculated. Studies were categorized by PES phenotype as normal, esophageal web, cricopharyngeal bar, or narrow PES. PES distention ratios were evaluated across bolus trials and within PES phenotypes using a mixed-methods repeated-measures analysis of variance. Results Of the 50 studies, there were 11 normal, 16 web, 10 bar, and 13 narrow PES. Quantitative differences were present for the narrowest (p = .01) and widest (p = .002) points across bolus volumes. No difference was present in distention ratio (p = .2) across volumes. Evaluating the PES phenotype, web, normal, bar, and narrow PES distention ratios differed (p = .03). Bar and PES narrow distention ratios were lower compared to that of the normal group (p = .01 for normal vs. bar and p = .02 for normal vs. PES narrow). Conclusions PES distention ratio stability across varying bolus volumes and phenotypes suggests that a reduction in trials during a VFSS may permit an equivalent PES evaluation to traditional exams. Ultimately, this could improve our understanding and accurate diagnosis of PES dysfunction.