Reliability of The Nasopharyngeal Fiberscope (NPF) for Assessing Velopharyngeal Function

Abstract

Simultaneous side-view nasopharyngeal fiberscopic (NPF) and lateral Cinefluoroscopic (cine) recordings were taken for two normal subjects to determine the stability of NPF placement for the study of velopharyn-geal function, and the reliability and validity of NPF findings. The results indicate that the NPF was highly stable during the several velopharyngeal activities examined, the NPF tip maintaining a rela— tively constant relationship within the vertebral complex. Therefore, it seems likely that similar NPF views are obtained on different occasions with a subject. The findings also indicate that measurements can be made from NPF still photos for several aspects of the velopharyngeal mechanism. However, measurements of the left lateral wall movement were not reliable. Measurement of velar movement from NPF correlated well with cine measures of velar movement, indicating validity of that NPF measure. This is an initial report about the use of the nasopharyngeal fiberscope (NPF) for assessing velopharyngeal function. One kind of NPF instrumentation is considered, as well as sta— bility and positioning of NPF with that technique. Also reported are findings on the reliability and validity of measurements taken from NPF photographs.