Unilateral Versus Bilateral Injections of Botulinum Toxin in Patients with Adductor Spasmodic Dysphonia

Both unilateral and bilateral thyroarytenoid muscle injections of Botox provide effective management of voice symptoms in patients with adductor spasmodic dysphonia; however, the preferred injection technique has not been established. In this study, 16 patients were treated with unilateral injections (72 injections total) and 33 patients were managed with bilateral injections (133 injections total). Individual assignments to injection type were based on treatment previously received and dose was adjusted according to the patient's previous treatment response. An optimal treatment included a benefit lasting 3 months or more with side effects lasting 2 weeks or less. Compared to patients receiving bilateral injections, those receiving unilateral injections more frequently noted a benefit of 3 months or more (p = 0.03), side effects of 2 weeks or less duration (p = 0.03), as well as both a 3-month benefit and a 2-week or less side effect (p = 0.0004). Injection type had no effect on optimal Botox dosing with repeat injections. Successive unilateral injections at the same dose were more likely (p = 0.012) than successive bilateral injections to produce the same or longer duration of benefit. We conclude that a unilateral injection routine has a more optimal and consistent treatment effect/side effect profile.     

Longitudinal Effects of Botulinum Toxin Injections on Voice-Related Quality of Life (V-RQOL) for Patients with Adductory Spasmodic Dysphonia

Adductory spasmodic dysphonia is a focal dystonia of laryngeal muscles. Patients with this disorder typically have severe vocal difficulties, with significant functional, social, and emotional consequences. There is no widely accepted cure for this condition, however, botulinum toxin injections of the thyroarytenoid muscles are considered by most voice clinicians to be the state of the art treatment. Based on extensive experience treating patients for adductory spasmodic dysphonia, we feel that traditional means of voice assessment do not adequately measure either the disease severity or the treatment outcomes. That is, listening to or acoustically analyzing limited phonatory samples does not capture the functional, social, and emotional consequences of this disorder. These consequences will be reflected in a patient's voice-related quality of life (V-RQOL). Using a validated voice outcomes instrument, the V-RQOL Measure, the purpose of this study was to quantify longitudinal changes in the V-RQOL of patients with adductory spasmodic dysphonia who are undergoing botulinum toxin injections. Twenty-seven consecutive new patients presenting with dysphonia to our institution during an 18-month period were diagnosed with adductory spasmodic dysphonia, and treated patients were evaluated prospectively using the V-RQOL Measure. Results indicated that (1) V-RQOL was initially very low for these patients, (2) botulinum toxin injections improved it significantly for each injection cycle studied, and (3) the magnitude of the treatment effect appears to change across injections.     

Voice-related Quality of Life in Laryngectomees: Assessment Using the VHI and V-RQOL Symptom Scales

The primary purpose of this study was to investigate the effect of the voice impairment across the physical, emotional, and functional domains in patients using valved speech following total laryngectomy with the help of two symptom specific scales. The study design used was a cross-sectional cohort. The setting was the Head and Neck Oncology Unit of a tertiary referral centre. Subjects were 54 patients who had undergone total laryngectomy. Two voice-specific questionnaires, the Voice-Related Quality of Life (V-RQOL-short form) Measure, and the Voice Handicap Index (VHI-long form) were used. The main outcome measure was patient perception of the voice following total laryngectomy in response to specific questions correlated with sociodemographic/treatment factors. Responses were received from 40 males and 14 females (response rate of 85.7%) with a median age of 63.4 years (range: 37-84). The V-RQOL overall analysis showed that 3 patients (5.6%) scored "excellent," 29 patients (53.7%) "fair to good," 14 patients (25.9%) "poor to fair," and 8 patients (14.8%) "poor." Analysis of the VHI revealed that 20 patients (37.0%) had a minimal handicap, 20 patients (37.0%) a moderate handicap, and 14 patients (25.9%) had a serious voice handicap. The individual domain or subscale scores for the VHI revealed a mean (SD) functional score of 15.8 (7.7), a physical score of 13.6 (7.2), and finally an emotional score of 11.6 (8.9). Functional aspects of the voice were significantly affected by age, radiotherapy, and chemotherapy (Spearman rho, P=0.01; Mann-Whitney, P=0.04 and P=0.01). The physical aspects of the voice were significantly affected by age and chemotherapy (Spearman rho, P=0.004; Mann-Whitney, P=0.04). Only age significantly affected the emotional aspects of the voice (Spearman rho, P=0.002). We found a strong correlation (Spearman rho, P<0.001) between the V-RQOL and VHI questionnaires. Our study revealed that the V-RQOL and VHI scores in our series of patients following voice restoration in laryngectomees were consistent with that reported in the literature. Only age, radiation, and chemotherapy were seen to influence the voice handicap scores. In addition, both symptom scales had good correlation between them and either one could be used with reliability in laryngectomees with a few modifications.     

Botulinum Toxin Type B for Treatment of Spasmodic Dysphonia: A Case Report

Although treatment with botulinum toxin type A (BTXA) has become the standard of care for most patients with laryngeal dystonia, its use is limited by the development of resistance to the toxin in some patients. Botulinum toxin type B (BTXB) has been found to be safe and effective in the treatment of cervical dystonia, but it has not been used previously to treat spasmodic dysphonia. Our experience with BTXB in a patient who developed resistance to BTXA suggests that BTXB may be safe and effective for the treatment of laryngeal dystonia, as well.