Image-based measurement of post-swallow residue: the normalized residue ratio scale

Dysphagia. 2013 Jun;28(2):167-77. doi: 10.1007/s00455-012-9426-9. Epub 2012 Oct 23.

Abstract

Post-swallow residue is considered a sign of swallowing impairment. Existing methods for capturing post-swallow residue (perceptual and quantitative) have inherent limitations. We employed several different perceptual and quantitative (ratio) methods for measuring post-swallow residue on the same 40 swallows and addressed the following questions: (1) Do perceptual and quantitative methods demonstrate good agreement? (2) What differences in precision are apparent by measurement method (one-dimensional, two-dimensional, and circumscribed area ratios)? (3) Do residue ratios agree strongly with residue area measures that are anatomically normalized? Based on the findings of this series of questions, a new method for capturing residue is proposed: the Normalized Residue Ratio Scale (NRRS). The NRRS is a continuous measurement that incorporates both the ratio of residue relative to the available pharyngeal space and the residue proportionate to the size of the individual. A demonstration of this method is presented to illustrate the added precision of the NRRS measurement in comparison to other approaches for measuring residue severity.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Deglutition / physiology*
  • Deglutition Disorders / diagnostic imaging*
  • Deglutition Disorders / physiopathology
  • Fluoroscopy*
  • Humans
  • Manometry / methods
  • Pharynx / diagnostic imaging*
  • Pharynx / physiopathology