Diane M. Bless

Histologic and Rheologic Characterization of Vocal Fold Scarring

Scarring of the vocal fold causes considerable dysphonia and presents significant treatment challenges. A rabbit model was developed to investigate the histologic ultrastructure and rheologic properties of the scarred vocal fold lamina propria. Eleven rabbit larynges were scarred by means of forcep biopsy. Sixty days postoperatively, the rabbits were sacrificed and their vocal folds were harvested. Histological analysis of the scarred and normal lamina propria was completed for collagen, procollagen, elastin, and hyaluronic acid. Linear viscoelastic shear properties of the tissues were also measured, including elastic shear modulus and dynamic viscosity. Compared to normal vocal fold lamina propria, scarred tissues demonstrated significantly less collagen, an increase in procollagen, and a decrease in elastin. Rheologically, both elastic shear modulus and dynamic viscosity were significantly higher for the scarred tissues. Increased stiffness and viscosity do not appear to result from an increase in collagen, but rather appear to be related to the presence of new, disorganized collagen scaffolding. Results are interpreted in terms of the possible role of interstitial proteins in the etiology of increased stiffness and viscosity, which requires further investigation. This animal model should allow for systematic future investigations of vocal fold scarring and its treatment.

Characterization of Vocal Fold Scarring in a Canine Model

Objective The objective was to assess the histological and viscoelastic shear tissue properties of the scarred vocal fold lamina propria at 2 and 6 months postoperatively in a canine model.

Role of injectable collagen in the treatment of glottic insufficiency: a study of 119 patients.

Injectable bovine collagen has been used for treatment of glottic insufficiency at the University of Wisconsin Clinical Science Center since 1983. This report reviews our experience in treating 119 patients with a variety of vocal fold disorders manifested by glottic insufficiency. Many of the patients were referred because of prior treatment failures or problems that were impossible to treat with other modalities. Results were assessed by comprehensive voice evaluations using subjective patient self-assessments, perceptual judgments made by a panel of experts who had no prior knowledge of the study, objective assessments, and videostroboscopy. Objective assessment included vocal function measures and acoustic analysis. Results indicate that collagen not only is comparable to other injection filler substances but also has unique advantages as a bioimplant. Collagen injection seems uniquely suited for treatment of several problems, including vocal fold atrophy, focal defects, minimal glottic insufficiency, and scarred vocal folds that are not managed optimally with Teflon injection. Overall there were no serious complications and treatment was effective for a broad spectrum of problems. In most instances the correction persisted, and in those instances in which injected collagen seemed improperly distributed, the vocal fold was recontoured or the implant removed without appreciable damage to the surrounding tissues. Injectable collagen has been extensively studied and deserves to be included in the armamentarium of the laryngeal surgeon.

Vibratory characteristics of the vocal folds in young adult and geriatric women

Summary Acoustic, aerodynamic, and videostroboscopic measures of vocal fold function were collected and analyzed during phonation of the vowel /i/ on 20 geriatric and 20 young adult normal female speakers. Acoustic and aerodynamic measures were analyzed for mean fundamental frequency, mean percent jitter, shimmer, sound pressure level, and mean airflow rate. Results indicate that the geriatric women exhibited greater shimmer and more intersubject variability in F 0 and mean airflow rate. Stroboscopic findings revealed a geriatric profile of greater aperiodicity, incomplete glottal closure, mucosal wave alterations, and reduced amplitude of vibration when compared to their younger counterparts. The findings are discussed in terms of the reported age-related anatomic and physiologic changes.

Manual circumlaryngeal therapy for functionaldysphonia: An evaluation of short- and long-term treatment outcomes

Manual circumlaryngeal therapy (manual laryngeal musculoskeletal tension reduction) was used to treat 25 consecutive functional dysphonia patients. Pre- and post-treatment audio recordings of connected speech and sustained vowel samples were submitted to auditory-perceptual and acoustical analysis to assess the immediate and long-term effects of a single treatment session. To complement audio recordings, subjects were interviewed in follow-up regarding the stability of treatment effects. Pre- and post-treatment comparisons demonstrated significant voice improvements. No significant differences were observed between post-treatment measures, suggesting that vocal gains were maintained. Interviews revealed 68% of subjects reported occasional partial recurrences, typically less than 4 days in duration, which resolved spontaneously. These results replicate and extend previous research suggesting the utility of manual circumlaryngeal therapy for functional voice disorders.

Comparison of high-speed digital imaging with stroboscopy for laryngeal imaging of glottal disorders.

Objectives: High-speed digital imaging (HSDI), unlike stroboscopy, is a frequency-independent visualization technique that provides detailed biomechanical assessment of vocal physiology due to increased temporal resolution. The purpose of this study was to investigate the clinical value of HSDI compared to that of stroboscopy across 3 disorder groups classified as epithelial, subepithelial, and neurologic disorders. Methods: Judgments of vibratory features of vocal fold edge, glottal closure, phase closure, vertical level, vibratory amplitude, mucosal wave, phase symmetry, tissue pliability, and glottal cycle periodicity from 252 participants were performed by 3 experienced raters. Results: The results revealed that 63% of the data set was noninterpretable for assessment of vibratory function on stroboscopic analysis because of the severity of the voice disorder (100% of participants with severe voice disorders and 64% of participants with moderate voice disorders), whereas HSDI resulted in analysis of 100% of the data. The neuromuscular group (74%) was the most difficult to analyze with stroboscopy, followed by the epithelial (58%) and subepithelial groups (53%), secondary to the severity of hoarseness. Conclusions: Because it is desirable in clinical examination to observe vocal fold vibrations, which cannot be done in cases of severe dysphonia, HSDI may aid in clinical decision-making when patients exhibit values exceeding 0.87% jitter, 4.4% shimmer, and a signal-to-noise ratio of less than 15.4 dB on acoustic analysis. These measures could serve as minimal indications for use of HSDI. The data suggest that HSDI can be viewed as augmentative to stroboscopy, particularly in cases of moderate to severe aperiodicity, in which HSDI may aid clinical decision-making.

Autologous collagen vocal fold injection: A preliminary clinical study

This preliminary study reports the first use of injectable autologous collagen for vocal fold augmentation. In previous studies, the authors showed cross‐linked bovine collagen to be effective in more than 150 patients with glottic incompetence, particularly those with focal defects or scarred or atrophic vocal folds. However, concerns about possible adverse immunologic responses to the bovine material have limited its use.

Sulcus vocalis: a rational analytical approach to diagnosis and management.

The term sulcus vocalis has been applied to a spectrum of disorders ranging from minor vocal fold indentations to destructive lesions causing severe dysphonia. To clarify the pathophysiology and to develop a more rational approach to treatment, we report a series of sulcus patients including 20 surgical cases. Clinical and histopathologic analysis produced a clinically useful classification: type 1 is a physiologic variant accentuated by atrophy but with intact lamina propria; types 2 (sulcus vergeture) and 3 (sulcus vocalis) are characterized by severe dysphonia, loss of vibratory activity, and destruction of the functional superficial lamina propria. These latter cases respond favorably to microsurgery designed to remove destroyed tissue, release scar contracture, and promote mucosal redraping by regional undermining. Further study of the extracellular matrix of the superficial lamina propria (Reinkes space) might indicate a common pathway in the pathogenesis of sulcus deformities and other related benign vocal fold lesions.

Personality and voice disorders: a multitrait-multidisorder analysis.

To examine whether personality has causal, concomitant, or outcome status in common voice disorders, a vocally normal control group and 4 groups with voice disorders--functional dysphonia (FD), vocal nodules (VN), spasmodic dysphonia (SD), and unilateral vocal fold paralysis (UVFP)--were compared using the Multidimensional Personality Questionnaire (MPQ). Univariate and discriminant analyses confirmed that the FD and VN groups differed significantly from each other, the controls, and the other voice-disordered groups at both a superfactor and lower-trait level of personality description. The FD group was introverted, stress reactive, alienated, and unhappy. The VN group was described as socially dominant, stress reactive, aggressive, and impulsive. Comparisons involving the SD, UVFP, and the control subjects did not identify consistent personality differences. While group trends supported the central tenets of a trait theory outlining the dispositional bases of FD and VN, further research is needed to elucidate the specific causal mechanism(s) in individual cases. The disability hypothesis, which suggests that personality features represent the negative effects of vocal disability, was not strongly supported.

Clinical experience with injectable collagen for vocal fold augmentation.

Injectable collagen appears to be safe and effective in treating glottic insufficiency. Fifty-four patients received vocal-fold injections of Zyderm Collagen Implant and their responses were followed for as long as 2 years. Videostroboscopy affords the best assessment of glottic function and correlates well with vocal quality. Maximum phonation time and transglottic airflow are the most sensitive measures of glottic efficiency; follow-up studies indicate that responses to treatment vary at 1 week, tend to stabilize by 3 months, and show only slight decrement over 1 year. One patient experienced a delayed hypersensitivity reaction, but it did not adversely affect his result. The use of cross-linked preparations of collagen should decrease the incidence of such responses. Treated patients were divided into diagnostic groups. Patients with bilaterally scarred vocal folds did not appear to respond optimally to collagen injection. Vocal rehabilitation was better if patients had at least one normal vocal fold. The best results occurred in patients with unilateral vocal fold paralysis and pre-existent bowing or atrophy did not affect these results. Collagen should be injected in the plane of the vocal ligament for best results; if the injection is too deep the implant is resorbed, and if too superficial, vocal-fold vibration is impaired.