Transoral radiofrequency of the terminal branches of the recurrent nerve in the treatment of adductor spasmodic dysphonia: our experience over 11 patients.

PURPOSE: Spasmodic dysphonia (SD) or laryngeal dystonia is as a rare vocal disorder characterized by involuntary action-induced endolaryngeal contraction. In the last decade, botulin toxin injection has become the standard treatment in adductor spasmodic dysphonia necessitating repetitive injections. The purpose of this study is to analyze retrospectively data from patients treated with the minimal-invasive transoral radiofrequency-induced thermotherapy (RFITT) of the terminal branches of the recurrent nerve. METHODS: Between 2009 and 2015, 11 patients (six females and five males aged from 32 to 91 years) with adductor SD were treated with RFITT. Pre-operative and post-operative vocal assessments (VHI-30, GRBASI, and acoustic-aerodynamics measurements), number of surgical revisions, delay between procedures, and post-operative complications were recorded. Statistical analyses were carried out on the first vocal assessment performed 2-8 weeks after the first procedure. RESULTS: Based on available data from ten patients, voice handicap index (VHI) showed improvement with a mean value of -17.7 points (p-value (pval) = 0.014, adjusted p-value (adj pval) = 0.21); instability has also revealed improvement in six patients (pval = 0.05, adj pval = 0.31). Four patients underwent only one procedure including one patient showing still long-term beneficial results after 5 years of follow-up. Other patients required one to three new procedures with an average time between procedures of 15.3 months. Over 24 surgeries performed on a total of 11 patients, one definitive treatment-related severe adverse event was reported. CONCLUSION: Thanks to long-lasting effect, repetitive treatments are less frequent compared to botulin toxin therapy. In our opinion, RFITT is a promising alternative to botulin toxin as a second-step procedure in case of toxin resistance or patient's lack of compliance.

Bilateral Posterior Cricoarytenoid Myoneurectomy for Abductor Spasmodic Dysphonia.

OBJECTIVE: To discuss the utility and outcomes of bilateral myoneurectomy for treatment of abductor spasmodic dysphonia. METHODS: Bilateral myoneurectomy is a known treatment option for patients with adductor spasmodic dysphonia. Its use for treatment of abductor spasmodic dysphonia, however, has not been documented previously. In this case report, treatment and long-term outcomes of abductor spasmodic dysphonia with bilateral myoneurectomy are discussed. RESULTS: A 50-year-old male presented with abductor spasmodic dysphonia. His initial Voice Handicap Index-10 (VHI-10) score was 29, and he had breathy breaks during 60 series. He had no improvement in vocal quality after 6 botulinum toxin injections over 21 months. He underwent staged bilateral posterior cricoarytenoid partial myoneurectomy, with the left posterior cricoarytenoid myoneurectomy performed 33 months after presentation and right posterior cricoarytenoid myectomy 11 months later. Eight years postoperatively, his VHI-10 score was 12. During postoperative 60 series, the patient demonstrated few breathy breaks. Overall, the patient reports improved quality of life and satisfaction with his voice. CONCLUSION: This is the first report of a long-term follow-up data for bilateral, endoscopic, partial posterior cricoarytenoid muscle myoneurectomy to treat refractory abductor spasmodic dysphonia. Long-term VHI-10 results suggest improvement of symptoms, despite mild difficulty with 60 series. While botulinum toxin therapy is the mainstay of management for abductor spasmodic dysphonia, surgical treatment is a potential alternative at least for refractory cases.

The effect of unilateral thalamic deep brain stimulation on the vocal dysfunction in a patient with spasmodic dysphonia: interrogating cerebellar and pallidal neural circuits.

Spasmodic dysphonia (SD) is a neurological disorder of the voice where a patient's ability to speak is compromised due to involuntary contractions of the intrinsic laryngeal muscles. Since the 1980s, SD has been treated with botulinum toxin A (BTX) injections into the throat. This therapy is limited by the delayed-onset of benefits, wearing-off effects, and repeated injections required every 3 months. In a patient with essential tremor (ET) and coincident SD, the authors set out to quantify the effects of thalamic deep brain stimulation (DBS) on vocal function while investigating the underlying motor thalamic circuitry. A 79-year-old right-handed woman with ET and coincident adductor SD was referred to our neurosurgical team. While primarily treating her limb tremor, the authors studied the effects of unilateral, thalamic DBS on vocal function using the Unified Spasmodic Dysphonia Rating Scale (USDRS) and voice-related quality of life (VRQOL). Since dystonia is increasingly being considered a multinodal network disorder, an anterior trajectory into the left thalamus was deliberately chosen such that the proximal contacts of the electrode were in the ventral oralis anterior (Voa) nucleus (pallidal outflow) and the distal contacts were in the ventral intermediate (Vim) nucleus (cerebellar outflow). In addition to assessing on/off unilateral thalamic Vim stimulation on voice, the authors experimentally assessed low-voltage unilateral Vim, Voa, or multitarget stimulation in a prospective, randomized, doubled-blinded manner. The evaluators were experienced at rating SD and were familiar with the vocal tremor of ET. A Wilcoxon signed-rank test was used to study the pre- and posttreatment effect of DBS on voice. Unilateral left thalamic Vim stimulation (DBS on) significantly improved SD vocal dysfunction compared with no stimulation (DBS off), as measured by the USDRS (p < 0.01) and VRQOL (p < 0.01). In the experimental interrogation, both low-voltage Vim (p < 0.01) and multitarget Vim + Voa (p < 0.01) stimulation were significantly superior to low-voltage Voa stimulation. For the first time, the effects of high-frequency stimulation of different neural circuits in SD have been quantified. Unexpectedly, focused Voa (pallidal outflow) stimulation was inferior to Vim (cerebellar outflow) stimulation despite the classification of SD as a dystonia. While only a single case, scattered reports exist on the positive effects of thalamic DBS on dysphonia. A Phase 1 pilot trial (DEBUSSY; clinical trial no. NCT02558634, clinicaltrials.gov) is underway at the authors' center to evaluate the safety and preliminary efficacy of DBS in SD. The authors hope that this current report stimulates neurosurgeons to investigate this new indication for DBS.

A comparative study of voice outcomes and complication rates in patients undergoing injection laryngoplasty performed under local versus general anaesthesia: an Adelaide voice specialist's experience.

OBJECTIVE: To compare clinical outcomes and complication rates in patients undergoing injection laryngoplasty performed under local versus general anaesthesia. METHODS: A retrospective review was conducted of patients who underwent injection laryngoplasty performed by a single laryngologist in a tertiary Australian laryngology centre, between February 2013 and December 2014. Patient demographics, anaesthetic modality and complications were recorded. Voice Handicap Index 10 and the Grade, Breathiness, Roughness, Asthenia, Strain scale were evaluated. RESULTS: Thirty-four laryngoplasties were performed under general anaesthesia and 41 under local anaesthesia, with mean patient ages of 59.5 and 68.8 years, respectively. Voice Handicap Index 10 scores were significantly improved post-injection (p 0.05). All aspects of the Grade, Breathiness, Roughness, Asthenia, Strain scale showed significant improvement post-injection, except asthenia. There were seven (9.3 per cent) minor complications (five in the general anaesthesia group, two in the local anaesthesia group), all managed conservatively. CONCLUSION: Injection laryngoplasties performed under general anaesthesia and local anaesthesia offer similar voice outcomes, with comparable complication rates. Hence, development of a management algorithm for injection laryngoplasties performed under local anaesthesia is recommended.

Reduction of Parkinson's-related dysphonia by thyroplasty.

Parkinson's-related dysphonia has a negative impact on the quality of speech by increasing the effects of the associated dysarthria. When this dysphonia is related to vocal fold adduction defect, constituting a real glottic insufficiency, vocal fold medialization can be proposed after failure of intensive voice and speech therapy. Acoustic and aerodynamic voice and speech analysis techniques, perceptual evaluation and estimation of vocal handicap, associated with fiberoptic laryngoscopy were performed to determine the indication for vocal fold medialization in these patients with glottic insufficiency. Vocal fold medialization by Montgomery thyroplasty implant was performed under local anesthesia and neuroanalgesia in two patients with Parkinson's disease presenting a dysphonia refractory to speech therapy. Postoperative evaluation showed improvement of voice quality with an increased number of harmonics and improvement of aerodynamic parameters. Vocal fold medialization by Montgomery thyroplasty implant effectively improved voice quality in these two patients allowing a more effective vocal fold adduction. The reducing of the hypophonia has a positive effect on the quality of oral communication. The medialization thyroplasty technique, under local anesthesia, allows intraoperative control of the voice as well as removal of the implant when necessary.

Type I gore-tex laryngoplasty for glottic incompetence in mobile vocal folds.

OBJECTIVE: To determine the effectiveness of gore-tex medialization thyroplasty for the management of glottic incompetence (GI) in patients with mobile vocal folds. METHODS: Twenty patients with glottic incompetence (GI) and mobile vocal folds were retrospectively analyzed after gore-tex medialization laryngoplasty. Pre- and postoperative outcome measures including grade, roughness, breathiness, asthenia, strain of the voice (GRBAS), glottal function index (GFI), and voice-related quality of life (VRQOL) were compared to detect surgical effectiveness. Two anesthetic subgroups were identified and compared: general anesthesia, via laryngeal mask airway (LMA) anesthetic, and local anesthesia. RESULTS: Statistically significant differences were identified between pre- and postoperative VRQOL (P<0.0001), GFI (P<0.01), and composite GRBAS (P<0.0001) after a mean follow-up time of 7.8 months. Both the LMA and the local anesthetic subgroups demonstrated similar significance across these measures. GFI and VRQOL scores demonstrate a moderate correlation (ρ=0.71). Perceptual voice quality (GRBAS) correlates slightly better with VRQOL scores (ρ=-0.6; P<0.01) than qualitative measures of glottal function (GFI) (ρ=0.43). CONCLUSION: Gore-tex thyroplasty provides reliable medium-term improvement in both perceptual and subjective voice parameters in the setting of GI with mobile vocal folds.

Selective lateral laser thyroarytenoid myotomy for adductor spasmodic dysphonia.

OBJECTIVE: Selective lateral laser thyroarytenoid myotomy is a conceptually sound, simple, minimally invasive, repeatable and predictable new surgical procedure for treating adductor spasmodic dysphonia. This paper aims to introduce and describe the surgical technique, and to present a clinical case series and its outcomes. STUDY DESIGN: A prospective, clinical case series treated with selective lateral laser thyroarytenoid myotomy, with follow up of 2.5 years. METHOD: Pre- and post-operative data were collected prospectively for patients undergoing selective lateral laser thyroarytenoid myotomy. These data included patient demographics, previous interventions for adductor spasmodic dysphonia, technical aspects of surgery and clinical outcome. Outcome data included clinical assessment, voice handicap index, need for further intervention, and patient satisfaction assessed by subjective improvement (detailed subjectively by the patients themselves and objectively using the Glasgow benefit inventory). RESULTS: Four patients (two men and two women; mean age 65 years; age range 41-80 years) were included. The mean duration of adductor spasmodic dysphonia was 11 years. All patients had previously been treated with botulinum toxin A. All patients reported improvement in voice quality, fluency, sustainability and elimination of voice breaks over 2.5 years' follow up. Clinical assessment revealed no alteration in mucosal wave, and complete relief of hyperadduction was observed on phonation. No patients required supplementary botulinum toxin treatment during follow up. CONCLUSION: Selective lateral laser thyroarytenoid myotomy seems to represent a curative procedure for adductor spasmodic dysphonia, a chronic, debilitating condition. This procedure is conceptually simple, minimally invasive and repeatable. It also seems to offer a safe and lasting alternative to botulinum toxin therapy.