A species comparison of videofloroscopic metrics of swallowing in healthy dogs and cats
Megan Grobman, Elizabeth Luciani, Carol ReineroAbstract
Background
Videofluoroscopic swallow studies (VFSS) are the criterion standard for diagnosing dysphagia in veterinary species. However, a lack of normative swallowing variables in cats hinders assessment of cats with potential aerodigestive disease. Species variation in swallowing could lead to over- and under-interpretation of findings on VFSS, resulting in misdiagnosis.
Hypothesis/Objectives
Compare differences in objective swallowing metrics between cats and dogs using VFSS. We hypothesize that cats will show differences in objective swallowing metrics on VFSS compared with dogs.
Animals
Healthy adult cats (n = 13) and dogs (n = 12) without clinical signs (CS) of respiratory or alimentary disease.
Methods
Prospective, cross-sectional study. Cats and dogs underwent standardized VFSS. All were evaluated according to 16 objective metrics and compared between species. Between group comparisons were made using Mann–Whitney-U, T-test, or Fischer’s exact test with a P < .05 significance level for all comparisons.
Results
Cats had significantly longer inter-swallow intervals, shorter pharyngeal transit times, and more pharyngeal swallows to generate primary peristalsis compared with dogs (P < .05). Cats were also more likely to have esophageal volume accumulation and slowing of distal esophageal transit time compared with dogs (P < .05). Physiologic reflux was identified in 2 (15.4%) cats vs 6 (50%) dogs. Pathologic penetration-aspiration (P-A score: 7; aspiration without attempt to cough) was found in 1 cat despite a lack of respiratory or alimentary CS.
Conclusions and clinical importance
Species variation should be considered when interpreting VFSS. In 1 cat, occult tracheal aspiration of contrast (P-A score 7) was detected without accompanying cough.