Voice gains following thyroplasty may improve over time.

Type I thyroplasty for unilateral vocal fold paralysis restores voice. The purpose of this study was to evaluate measures of voice before thyroplasty, and at 3 months and 1 year after surgery. Of interest was whether vocal improvement in the first weeks after surgery was maintained or even enhanced over time. A total of 40 patients with unilateral paralysis underwent type I thyroplasty with or without arytenoid adduction. Perceptual, acoustic and aerodynamic measures of voice were studied. Perceptual analysis determined that optimal postoperative voice quality evolved over the first year. Acoustic indices of perturbation demonstrated progressive improvement over 12 months, whereas pitch and intensity ranges were increasingly extended. Postoperative glottal flow rates were normalized and phonation times were significantly longer, with benefits maintained over time. All perceptual, aerodynamic and acoustic measures of voice were improved 3 months after thyroplasty, with many measures further improved at 1 year. Such findings provide evidence that voice outcome progressively evolves over the first 12 months after surgery.

Voice outcome following thyroplasty in patients with cancer-related vocal fold paralysis.

Medialization laryngoplasty restores voice in patients with unilateral laryngeal paralysis. Of question was whether patients with vocal fold paralysis resulting from cancer or its treatment had as good a post-operative voice result as patients with vocal fold paralysis of benign etiology. The purpose of the present study was to compare post-operative perceptual, acoustic, aerodynamic, and quality of life data in these two patient groups. Twenty-eight patients with vocal fold paralysis secondary to malignancy or its treatment were age and gender-matched with patients with paralysis resulting from benign origin. Pre- and post-operative perceptual judgments of pitch, loudness and quality were rated independently by two speech-language pathologists. A digital audiotape of the patient's voice was analyzed using Soundscope software. Fundamental frequency, conversational intensity and perturbation were evaluated. Glottal flow rates in propositional speech, phonation times and extent of pitch and loudness ranges were also measured. Three quality of life surveys, the Short Form-36 general health survey, the Voice Handicap Index, and the Voice Outcomes Study were administered. Results of voice testing indicated that perceptual, acoustic and aerodynamic data were significantly improved 3 months after thyroplasty in all patients regardless of whether they had a history of cancer. Quality of life data, however, distinguished the two groups. In particular, the general health measure found a significant difference in physical functioning and overall vitality, although satisfaction with improved voice was equally appreciated in both patient groups. Of clinical significance is that though general health may differ, patients with cancer-related laryngeal paralysis can expect to have as good a voice outcome following thyroplasty as patients with paralysis of benign etiology.

Determination of the optimal conditions for laryngeal pacing with the Itrel II implantable stimulator.

OBJECTIVE: To determine the optimal stimulus paradigm, electrode orientation, and configuration of an implantable stimulator used to reanimate the posterior-cricoarytenoid (PCA) muscle in case of bilateral vocal fold paralysis (BVFP). STUDY DESIGN: Acute studies were conducted on 13 canines implanted with Itrel II systems with or without PCA innervation. PCA stimulus-response characteristics were obtained by measuring stimulated vocal fold displacement endoscopically. RESULTS: The denervated PCA was only 10% to 25% as responsive to stimulation as the innervated PCA. However, the response could be increased to 38% and 61% if the Itrel was modified to deliver 1 and 2 msec pulses, respectively. Stimuli delivered centrally to the muscle 5 mm from the median raphe improved performance. CONCLUSION AND SIGNIFICANCE: The optimal stimulus paradigm identified in this study (1 msec pulses delivered at 30 to 40 Hz and 2 to 8.5 mA) has been applied to implanted BVFP patients and improved outcome. Information regarding optimal electrode orientation could also be important to future clinical trials.

Voice outcome following lateral laryngotomy to remove teflon granuloma.

Formation of a Teflon granuloma may lead to progressive dysphonia and airway compromise. Excision of the granuloma by lateral laryngotomy allows preservation of the uninvolved lamina propria. A sternothyroid muscle flap or Silastic implant to medialize the vocal fold restores a straight glottal edge and optimizes voice production. Fifteen patients underwent removal of a Teflon granuloma via a lateral approach. Analysis of data revealed improved acoustic and aerodynamic parameters of voice following surgery. Indices of acoustic perturbation were reduced, and vocal pitch normalized. While the dynamic pitch range was unchanged, the capacity to vary loudness was enhanced. Flow rates in speech, abnormally elevated before surgery, normalized after the procedure, and phonation times were significantly longer. Perceptual and stroboscopic data confirmed that voices were improved, but not normal.

Effect of mitomycin-C on vocal fold healing in a canine model.

For evaluation of the effect of topical mitomycin-C on vocal fold healing and return of function after surgical excision of mucosa, 6 dogs underwent suspension microlaryngoscopy with bilateral microflap excision of vocal fold mucosa. Topical mitomycin-C, a chemotherapeutic agent and a fibroblast inhibitor, was applied randomly to one side, with the contralateral side serving as the control. Laryngeal videostroboscopy (LVS) was performed on each animal before the operation, at 2 weeks, and before sacrifice at 4 weeks. Both functional analysis with LVS and histologic analysis were performed in a blinded fashion to determine the effect of mitomycin-C on healing. Histologic analysis was augmented with computer morphometrics. The LVS revealed diminished mucosal wave vibration in the vocal folds treated with mitomycin-C, as well as a more atrophic appearance to the vibratory surface. The vocal folds treated with mitomycin-C showed fewer fibroblasts and less collagen within the superficial layer of the lamina propria than the control vocal folds (p < .05, Student's t-test, paired analysis). Inflammatory infiltrate was not significantly different between the two sides. Consistent with the known suppression of fibroblast proliferation by mitomycin-C, the treated vocal folds showed less connective tissue response to the surgical injury. In contrast to the reported positive effects of mitomycin-C on tracheal and glottic stenosis, the observed decrease in the healing response in the present study had negative consequences on the vocal fold vibratory pattern.

Outcomes assessment following treatment of spasmodic dysphonia with botulinum toxin.

Spasmodic dysphonia (SD), a disabling focal dystonia involving the laryngeal musculature, is most commonly treated by the intramuscular injection of botulinum toxin (BTX). Although the treatment is well tolerated and generally produces clinical voice improvement, it has never been statistically shown to alter the patient's perception of voice quality or general health. Declining resources for medical care mandate that treatment outcomes be documented. A prospective analysis of the effects of BTX on the patient's perception of voice and general health was undertaken. The Voice Handicap Index (VHI) and Short Form 36 (SF-36) surveys were administered to patients before treatment and 1 month after. Pretreatment and posttreatment scores were analyzed with a Student's t-test. On the VHI, improvements in the patients' perception of their functional, physical, and emotional voice handicap reached statistical significance (p < or = .0005). On the SF-36, patients had statistically significant improvements in mental health (p < or = .03) and social functioning (p < or = .04). Treatment of SD with BTX significantly lessened the patients' perception of dysphonia. In addition, it improved their social functioning and their perception of their mental health. These outcome measures justify the continued treatment of SD with BTX.

The effects of chronic electrical stimulation on laryngeal muscle physiology and histochemistry.

The present study examined the effects of functional neuromuscular stimulation (FNS) on posterior cricoarytenoid (PCA) muscle physiology and histochemistry. In 4 canines, 10 cm of the recurrent laryngeal nerve was resected. A patch electrode array was implanted for PCA stimulation. FNS was applied to 2 canines for a period of 4 weeks with 2 additional animals serving as nonstimulated controls. Results indicated that FNS increased PCA muscle contractility over the period of intervention but had no effect on contraction speed. FNS also protected the muscle from atrophy by preventing muscle weight loss and type 2 fiber deterioration. Finally, it rescued muscle fibers from ensuing fibrosis.

Histomorphometric and laryngeal videostroboscopic analysis of the effects of corticosteroids on microflap healing in the dog larynx.

The histologic and functional effects of unilateral, layered corticosteroids on lateral microflap healing in 15 dogs were analyzed. Histologic sections of steroid-treated vocal folds (VFs) were studied with computer morphometry to examine differences in the tissue healing response. Paired analysis revealed increases in the inflammatory infiltrate around the microflap in the steroid-treated VFs at 2, 4, and 6 weeks (6.3%, 30.6%, and 34.9%, all with p < .02). The neovascular response in the steroid-treated VFs was less at 2 weeks (-20.9%, p < .005) but greater at 4 and 6 weeks (16.3% and 4.3%, p < .005). To better characterize the effect of steroids on the healing process, a normal, time-dependent distribution was applied to the histologic data and demonstrated a delay in the steroid-treated VF tissue response of 12 days for the inflammatory infiltrate and 21 days for the neovascular response. Qualitative and quantitative analysis of in vivo laryngeal videostroboscopy (LVS) samples taken preoperatively and at sacrifice could not identify significant differences in appearance, amplitude, mucosal wave, or suppleness between the 2 VFs. Therefore, although corticosteroids cause a delay in wound healing, LVS does not discern differences in microflap characteristics between healing steroid-treated and control VFs at 2, 4, or 6 weeks. If steroids are used, the surgeon should account for a probable delay in wound healing, but should not expect an overall difference in functional outcome.