Quantitative videofluoroscopic analysis of penetration-aspiration in post-stroke patients

Background : Dysphagia is a common complication of stroke and is a potential cause for aspiration and malnutrition and is also associated with poor outcome. Videofluoroscopic Swallowing Study (VFSS) is the most objective method for evaluation of swallowing disorders.
Aim : To investigate the incidence and characteristics of penetration-aspiration in post-stroke patients, and to study the relationship between penetration-aspiration and kinematic parameters of swallow.
Materials and Methods : We prospectively studied swallowing function in 105 consecutive post-stroke patients and 100 normal adults by videofluoroscopic swallowing studies. The severity of airway invasion, penetration-aspiration, was studied quantitatively and kinematic parameters of swallow i.e. oral transit time, pharyngeal transit time (PTT), pharyngeal delay timem (PDT), maximal extent of vertical and anterior movement of larynx and hyoid bone for four kinds of boluses were also studied. Logistic regression was used to analyze the association between aspiration and kinematic parameters of swallow.
Results : Stroke patients scored significantly higher scores on penetration-aspiration scale than the normal subjects (P < 0.001) during four bolus swallows. Logistic regression analysis showed that PTT, PDT, maximal extent of vertical laryngeal and hyoid movement were statistically associated with the prevalence of aspiration (P < 0.05).
Conclusion : Penetration-aspiration is common in stroke patients. Several kinematic parameters of swallow are associated with the presence of aspiration on fluoroscopy. These data demonstrate that VFSS may be helpful for objective identification of dysphagia in stroke patients.

Keywords
Stroket, dysphagi, kinematic analysis, penetration-aspiration, videofluoroscopic swallowing study