Introduction
Flexible nasendoscopy (FNE) is the most commonly performed examination
used for assessment of vocal cord movement. It is routinely performed on
patients with voice complaints and management is frequently based on the
findings. FNE is the current gold standard method of evaluation of vocal
cord motion, helping to distinguish between normal and reduced vocal
cord movement. However, this subjective assessment can lead to
inaccuracies and variability in diagnosis, especially in challenging
cases. There is no reliable objective measure of categorising vocal cord
movement from normal to complete paralysis. Furthermore, limited data
exist on how consistent otolaryngologists are at rating vocal cord
movement 1,2.
The reliability of clinicians differentiating between binary categories
of mobile and immobile vocal cords1,2 and the presence
or absence of paresis have been reported3. The former
studies reported a 95% inter-rater reliability and a 99% intra-rater
agreement for binary vocal cord assessment and the latter an inter-rater
reliability of 0.334 (Fleiss’s kappa). A three category scale
(paralysis, paresis, normal) was used in reliability studies in
paediatric patients4. They reported an inter-rater
reliability (Cohen’s kappa) of 0.67 for diagnosis of normal vs impaired
movement, and lesser reliability of 0.49 when identifying the degree of
movement (normal, paresis, paralysis). The intra-rater reliability
ranged from 0.48 to 1 (Fleiss’s kappa). There is currently no reliable
grading system for categorising vocal cord movement from normal to
complete paralysis, for example similar to the House Brackman scale used
to routinely grade facial nerve paralysis.
The aim of this study was to determine if experienced consultant head
and neck surgeons were accurate and consistent with their assessment and
grading of vocal cord movement.