Background:
Videofluoroscopy swallowing studies (VFSS) have identified features contributing to dysphagia in patients following head and nek cancer (HNC) treatment. High-resolution pharyngeal manometry (HRPM) is a novel technology that can reveal altered swallowing biomechanics. Accordingly, this study aimed to compare VFSS functional outcome measures with novel HRPM analysis of swallowing biomechanics in patients following multi-modal treatment for HNC.
Methods:
Retrospective swallow data analysis was conducted in adults referred for simultaneous VFSS and HRPM studies, presenting with moderate-severe dysphagia following HNC treatment. Pharyngeal residue and aspiration status were quantified on VFSS using the Normalised Residue Rating Scale, Penetration-Aspiration Scale, and the Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) grades. HRPM recordings were analysed using the online Swallow Gateway application and referenced to normative ranges. Spearman rank correlations determined the relationships between VFSS and HRPM continuous variables.
Results:
Swallow studies were available for fourteen patients (13 male, mean age 63y, ranging 48-74y). Reduced pharyngeal pressures were evident in 57% (8/14) of patients, and 43% (6/14) presented with upper oesophageal sphincter (UOS) dysfunction. Only two patients presented with both abnormalities. Increased UOS relaxation pressure was associated with increased DIGEST Safety and Summary Grades (r=0.600, p <0.005 and r=0.605, p <0.05, respectively). Reduced UOS opening was associated with increased DIGEST Safety Grades (r=-0.533, p <0.005). Prolonged UOS relaxation time correlated with increased DIGEST Efficiency and Summary Grades (r=0.698, p <0.005 and r=0.585, p <0.05, respectively). Abnormal pharyngeal contractility measures did not correlate significantly with any quantifiable VFSS outcomes.
Conclusion:
Moderate-severe dysphagia in patients following multi-modality HNC treatment is associated with two distinct HRPM biomechanical patterns: reduced pharyngeal contractile pressures, and UOS dysfunction. Pharyngeal residue and aspiration observed on VFSS were associated with UOS dysfunction measures but not pharyngeal contractile pressures. This study illustrates that HRPM swallow analysis can enhance VFSS assessment.