Monitoring the Outcome of Phonosurgery and Vocal Exercises with Established and New Diagnostic Tools

Abstract

Instrument-assisted measuring procedures expand the options within phoniatric diagnostics by quantifying the condition of the voice. The aim of this study was to examine objective treatment-associated changes of the recently developed vocal extent measure (VEM) and the established dysphonia severity index (DSI) in relation to subjective tools, i.e., self-evaluation via voice handicap index (VHI-12) and external evaluation via auditory-perceptual assessment of hoarseness (H). The findings for H (3 raters’ group assessment), VHI-12, DSI, and VEM in 152 patients of both sexes (age range 16–75 years), taken before and 3 months after phonosurgery or vocal exercises, were compared and correlated. Posttherapeutically, all of the recorded parameters improved (p<0.001). The degree of H reduced on average by 0.5, the VHI-12 score sank by 5 points, while DSI and VEM rose by 1.5 and 19, respectively. The correlations of these changes were significant but showed gradual differences between H and VHI-12 (r = 0.3), H and DSI (r = −0.3), and H and VEM (r = −0.4). We conclude that all investigated parameters are adequate to verify therapeutic outcomes but represent different dimensions of the voice. However, changes in the degree of H as gold standard were best recognized with the new VEM.

Validation and Classification of the 9-Item Voice Handicap Index (VHI-9i)

“…However, the VHI-9i did not correlate well with the two objective parameters DSI and VEM, and had only slightly higher correlations with GRB. This supports recent studies that all these vocal parameters measure different aspects of a patient’s voice and are neither mutually interchangeable nor redundant [ 31 , 36 , 41 , 43 ]. Due to the weak correlations, poor discriminating performance and sometimes impossible cut-off points, DSI, VEM and G ultimately had no part in our recommendation for the revised VHI-9i cut-off points.…”

“…The means were used for further exploration. While the degree of G serves as the overall indicator of dysphonia in the original GRBAS scale, it is regarded as gold standard for hoarseness evaluation in the GRB system presented here [ 31 ].…”

“…A small vocal capacity is described by a low VEM, a large VRP by a high VEM. The VEM emphasizes the vocal abilities and enables a classification of voice performance as a positive criterion [ 21 , 31 , 41 ]. Based on Müller’s investigation of 994 subjects [ 36 ], the resulting VEM scores were divided into percentiles, distinguishing a normal vocal capacity (≥108) from mildly reduced (<108 to ≥93), moderately (<93 to ≥69) and severely reduced (<69) vocal capacities.…”

Pathology-Related Influences on the VEM: Three Years’ Experience since Implementation of a New Parameter in Phoniatric Voice Diagnostics

“…Phoniatric voice diagnostics require sophisticated and highly specialized investigation methods, including objective and subjective measuring procedures [ 1 – 3 ]. Within this multifactorial approach, the recording of a voice range profile (VRP) under standardized conditions represents an established objective and noninvasive tool for the examination of vocal function [ 4 – 6 ].…”

“…Four studies analyzed the VEM to assess treatment outcomes. Three investigations dealt with benign organic changes of the vocal folds (VF: 61 polyps [ 12 ], 37 nodules [ 14 ], and 60 edema [ 15 ]), another one included 152 patients with various laryngeal pathologies ( n = 101) and functional dysphonia ( n = 51) [ 1 ]. All of these clinical trials revealed significantly increased VEM values after phonomicrosurgery or conservative treatment.…”