The Minimal Important Difference of Acoustic Voice Quality Index in the Treatment of Voice Disorders.

OBJECTIVES: The acoustic voice quality index (AVQI) is a reliable tool that objectively assesses dysphonia levels using six acoustic parameters. Despite its high criterion-related concurrent validity, diagnostic accuracy, and minimal detectable change derived from test-retest reliability, the minimal important difference (MID) of the AVQI has not been tested before. This study aimed to estimate the MIDs of AVQI for improvement audibly perceived by clinicians and self-reported improvement by patients. METHODS: A retrospective study was conducted on 110 patients who received treatment for voice disorders. Patients completed AVQI and Voice Handicap Index-10 (VHI-10) questionnaires before and after the therapy. The MIDs of the AVQI were estimated using the anchor of either auditory-perceptual judgment of total dysphonia levels by clinicians or the VHI-10 questionnaire by patients. A distribution-based approach was also used to complement the results. RESULTS: First, using the auditory-perceptual anchor, a decrease of 0.95 in the AVQI was estimated as the MID for clinicians' perception, as a result of the receiver operating curve. Then, using the patient-reported anchor, an improvement of 1.36 in the AVQI was estimated as the MID for patients' voice-related disability. The distribution-based approach also ensured the anchor-based results of both the MIDs. CONCLUSIONS: The AVQI is a reliable and valid tool for evaluating voice quality, and a 0.95 decrease in the AVQI represents a meaningful improvement for clinicians' perception, whereas a 1.36 decrease in the AVQI influences patients' self-reported disability. This study contributes to understanding the minimal change necessary for clinicians to make informed decisions and ensure patient satisfaction. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:2805-2811, 2024.

Validation of Subharmonics Quantification Using Two-Stage Cepstral Analysis.

OBJECTIVES: Hoarseness is primarily perceived as breathiness or roughness. Despite the various tools that quantitatively assess hoarseness, roughness has been difficult to quantify because of its complex acoustic structure, such as subharmonics. The parameter obtained from the two-stage cepstral analysis is promising for evaluating roughness. Thus, this study aimed to improve the accuracy of the parameter using a customized pitch setting and investigate the relationship between roughness and subharmonics. STUDY DESIGN: The design is a retrospective study. METHODS: Two-stage cepstral analysis was used to analyze the voice recordings of 455 participants, speech impaired and normal controls, using the Analysis of Dysphonia in Speech and Voice and Praat software. For validation, the ground truth of subharmonics was visually quantified using a narrowband spectrogram. The reliability and validity of the two-stage cepstral analysis and subharmonics measures on spectrograms were evaluated. RESULTS: The two-stage cepstral analysis showed a very strong correlation (r = 0.963) between the two software programs. Intra- and inter-rater reliability of the subharmonics measures on spectrograms were also good. Two-stage cepstral analysis showed that even with customized pitch settings, the diagnostic systems and correlations for perceptual roughness and subharmonics were weak to moderate. The subharmonics measures on spectrograms showed a strong correlation with roughness and moderate diagnostic accuracy of subharmonics. CONCLUSIONS: The two-stage cepstral analysis showed some improvement in diagnostic accuracy and correlation with customized pitch settings, but it did not sufficiently detect subharmonics or roughness. The analysis using subharmonics measures on spectrograms proved the high correlation between subharmonics and roughness, indicating that developing acoustic analysis parameters that sufficiently detect subharmonics is necessary.

The Significant Influence of Hoarseness Levels in Connected Speech on the Voice-Related Disability Evaluated Using Voice Handicap Index-10.

OBJECTIVES: This retrospective study examines the influence of voice quality in connected speech (CS) and sustained vowels (SV) on the voice-related disability in patients' daily living documented by Voice Handicap Index-10 (VHI-10). METHODS: A total of 500 voice recordings of CS and SV samples from 338 patients with voice disturbances were included, along with the patients' age, diagnoses, maximum phonation time, and VHI-10. Dataset-1 comprised of 338 untreated patients, whereas Dataset-2 included 162 patients before and after phonosurgeries. As a preliminary study, the concurrent and diagnostic validities based on auditory-perceptual judgments were examined for cepstral peak prominence (CPP) and CPP smoothed (CPPS) for CS and SV tasks. Next, simple correlations and multivariate regression analyses (MRA) were performed to identify which of the acoustic measures for the CS or SV tasks significantly influenced the total score or improvement of VHI-10. RESULTS: The preliminary study confirmed high correlations with hoarseness levels as well as the excellent diagnostic accuracy of CPP and CPPS for both CS and SV tasks. In Dataset-1, the simple correlations and MRA results showed that cepstral measures in both tasks demonstrated moderate correlations with, and significant contribution to the total score of VHI-10, respectively. However, in Dataset-2, the changes of cepstral measures, as well as the median pitch after phonosurgeries in the CS tasks only, showed significant contributions to the improvement of VHI-10. CONCLUSION: The study demonstrated that the hoarseness levels in both the CS and SV tasks equivalently influenced the VHI-10 scores, and that the post-surgical change of voice quality only in the CS tasks influenced the improvement of voice-related disability in daily living.

Assessment of the Progression of Vertical Semicircular Canal Dysfunction and Increased Vestibular Endolymphatic Hydrops in Patients With Early-Stage Ménière Disease.

Importance: Vertical semicircular canals and endolymphatic hydrops play important roles in the pathophysiological mechanisms of Ménière disease. However, their characteristics and associations with disease progression during medical treatment have not been determined. Objective: To examine the function of both the horizontal and vertical semicircular canals in patients with Ménière disease and to evaluate the change in endolymphatic hydrops volume during medical treatment, including treatment with diuretic therapy, over a 2-year period. Design, Setting, and Participants: This prospective longitudinal observational cohort study included 55 patients with definite unilateral Ménière disease and was performed in a tertiary care hospital in Japan. Participants were enrolled between April 1, 2017, and January 31, 2018, and those with vestibular migraine were excluded. All participants received education regarding diet and lifestyle modifications and treatment with betahistine mesylate (36 mg daily) and/or an osmotic diuretic (42-63 mg daily). Patients were followed up for vertigo and hearing evaluations at least once per month for more than 12 months and were instructed to record episodes of vertigo in a self-check diary. Audiometry was performed monthly, video head impulse testing and caloric testing were performed every 4 months, and magnetic resonance imaging was conducted annually. Data were analyzed from May 15, 2017, to January 31, 2020. Main Outcomes and Measures: Neurootological testing to evaluate vestibuloocular reflex gain over time, magnetic resonance imaging to evaluate the change in endolymphatic hydrops volume over time, and monthly vertigo and hearing evaluations for more than 12 months. Results: Among 55 participants with definite Ménière disease, 32 patients (58.2%) were female, and the mean (SD) age was 59.0 (15.1) years. The median disease duration was 2 years (interquartile range, 0-4 years), with 43 patients (78.2%) having an early stage (ie, disease duration ≤4 years) of Ménière disease. Over the 2-year study period, the vestibuloocular reflex gain decreased from 0.76 to 0.56 in the superior semicircular canals, for a difference of 0.20 (95% CI, 0.14-0.26) and from 0.68 to 0.50 in the posterior semicircular canals, for a difference of 0.18 (95% CI, 0.14-0.22). The maximum slow-phase velocity and vestibuloocular reflex gain in the horizontal semicircular canals were maintained. The volume ratio of vestibular endolymphatic hydrops increased from 19.7% to 23.3%, for a difference of 3.6% (95% CI, 1.4%-5.8%). The frequency of vertiginous episodes decreased, and the hearing level over the study period worsened from 40.9 dB to 44.5 dB, for a difference of 3.5 dB (95% CI, 0.7-6.4 dB). Conclusions and Relevance: In this study, during a 2-year period of medical treatment among patients with Ménière disease, vestibuloocular reflex gain decreased in the vertical semicircular canals but was maintained in the horizontal semicircular canals; the endolymphatic hydrops volume ratio increased, and the frequency of vertiginous episodes decreased. These findings describe the pathological progression of chronic Ménière disease and expand the understanding of its pathophysiological characteristics during the early stage of disease.

Intertext Variability of Smoothed Cepstral Peak Prominence, Methods to Control It, and Its Diagnostic Properties.

OBJECTIVES: This study aimed to estimate the intertext variability of smoothed cepstral peak prominence (CPPS), examine whether sound-processing techniques improved its variability and diagnostic capability, and evaluate the degree of intertext variability in detail with reference to the CPPS variabilities in sustained vowels. STUDY DESIGN: This was a retrospective study. METHODS: Text readings of 58 Japanese syllables were recorded from 210 speakers with different diagnoses and varying degrees of dysphonia, and were divided into six passages. Applying the sound-processing techniques to those passages, we prepared three sample types: (1) nonprocessed, (2) only-loud, and (3) only-voiced samples. The intertext CPPS variability and diagnostic properties were compared across the passages and sample types. For detailed analysis, we subsequently extracted 63 normophonic speakers who maintained constant quality in their vowel utterances to evaluate the degree of intertext CPPS variability in relation to the variabilities between repeated identical vowels and across different vowels. RESULTS: Although several combinations of passages showed moderate-to-large CPPS variabilities, those variabilities were decreased by either technique, especially the deletion of silent segments, which resulted in the best diagnostic accuracy. The degree of intertext CPPS variability for the only-voiced samples was comparable to that of the CPPS variabilities in sustained vowels. CONCLUSIONS: The sound-processing technique removing silent segments should be applied to enhance the diagnostic properties of CPPS. The additional technique of deleting unvoiced segments is worth adopting if clinicians and researchers seek to attenuate the influence of text differences in calculating CPPS values.