Classification of sequential swallowing types using videoendoscopy with high reproducibility and reliability.

Objective: This study aimed to classify sequential swallowing types using videoendoscopy (VE) avoiding radiation exposure and compare the results using videofluoroscopy (VF).

Design: Twenty-one healthy adults simultaneously underwent VF and VE during sequential straw drinking. Each discrete swallow was classified into an L-segmental type (laryngeal vestibule opens after swallow) or L-continuous type (laryngeal vestibule closure continues after swallow) using VF and a V-segmental type (velopharynx opens after swallow) or V-continuous type (velopharynx closure continues after swallow) using VE. Test-retest reproducibility and interrater and intrarater reliability were evaluated in ten healthy adults.

Results: Of 128 swallows, 94 were L-segmental and 34 were L-continuous types as per VF, whereas 95 were V-segmental and 33 were V-continuous types as per VE. The leading edge of the bolus at swallow onset was significantly deeper in L-continuous types (P = 0.001). Laryngeal vestibule closure on VF images corresponded to velopharyngeal closure on VE images for 127 of 128 swallows (κ = 0.98, P < 0.001). All subjects showed the same types of swallows in the first and the second studies. Both interrater and intrarater reliability were high.

Conclusion: VE showed high reproducibility and reliability in the classification of sequential swallowing types.