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Laryngeal dystonia (LD) is an isolated, task‐specific, focal dystonia characterized by intermittent spasms of laryngeal muscles impairing speech production. Although recent studies have demonstrated neural alterations in LD, the consistency of findings across studies is not well‐established, limiting their translational applicability. We conducted a systematic literature search to identify studies reporting stereotactic coordinates of peak structural and functional abnormalities in LD patients compared to healthy controls, followed by a coordinate‐based activation likelihood estimation meta‐analysis. A total of 21 functional and structural neuroimaging studies, including 31 experiments in 521 LD patients and 448 healthy controls, met the study inclusion criteria. The multimodal meta‐analysis of these studies identified abnormalities in the bilateral primary motor cortices, the left inferior parietal lobule and striatum, the right insula, and the supplementary motor area in LD patients compared to healthy controls. The meta‐analytical findings reinforce the current view of dystonia as a neural network disorder and consolidate evidence for future investigations probing these targets with new therapies. [ABSTRACT FROM AUTHOR]

Purpose: Laryngeal dystonia (LD) is a focal dystonia affecting laryngeal musculature with no known etiology or cure. The present study evaluated the sociodemographic and clinical features of patients diagnosed with LD. Materials and Methods: All patients diagnosed with LD at our University Hospital's Ear, Nose, and Throat Department between January 2017 and July 2023 were retrospectively analyzed. The study included 43 patients. Results: Out of the 43 patients, 19 (44%) were male. At the time of diagnosis, the mean age of the patients was 35.1 years (ranging from 17 to 65 years). The mean elapsed time between the first symptom onset and the first diagnosis was 49.2 months (min. 4 months, max. 240 months). Of the participants, 94% had adductor-type LD. None of the patients had a family history of LD. Of the patients, 9 (20%) experienced a life-altering event or trauma just before the onset of symptoms. All patients who consumed alcohol reported symptom relief with alcohol intake. A total of 67.6% of patients stated that their symptoms were triggered by stress. All of our patients received at least one Botulinum toxin injection, with an average of 2.75 dosages per patient. Conclusion: The gender distribution was approximately equitable between males and females. There was a tendency for men to receive a diagnosis earlier than women following the manifestation of symptoms. A significant number of patients associate the emergence of their symptoms with a stressful event or traumatic experience. This study represents the initial investigation into the sociodemographic characteristics of patients within the Turkish population. [ABSTRACT FROM AUTHOR]

The article discusses a case report of a 45-year-old male patient with abductor laryngeal dystonia (ABLD) who underwent pallidal deep brain stimulation (DBS) surgery. ABLD is a rare subtype of laryngeal dystonia characterized by breathy breaks during speech. The patient experienced immediate and remarkable efficacy of DBS, with full recovery from symptoms without recurrence. The study highlights the potential of pallidal DBS as a highly effective treatment for ABLD, offering new insights into the management of this challenging condition. [Extracted from the article]

Objectives: There is an absence of data in the literature regarding methods to improve the patient experience during the performance of awake in‐office laryngeal injections. This study sought to evaluate whether the use of local anesthetic or a vibrating instrument decreased overall pain experienced by patients with laryngeal dystonia, frequently referred to as spasmodic dysphonia (SD), undergoing transcervical botulinum toxin injections. Methods: This was an unblinded, prospective randomized control trial with a crossover design where each patient received transcutaneous transcricothyroid injection of botulinum toxin with alternating use of no anesthesia, local anesthesia (2% lidocaine in 1:100,000 epinephrine), and vibrating instrument in three consecutive laryngeal injections to treat adductor SD. Patients were randomized to the order they received these treatments. Patients measured pain on a 0–10 visual analogue scale (VAS) and selected their preferred technique after receiving all three analgesic modalities. Results: Thirty‐two patients completed the study. There was no statistically significant difference in pain between the three analgesic techniques (p = 0.38). The most preferred analgesic technique was the vibrating wand (44% (14/32)). Lidocaine was the second most preferred (37% (12/32)) and 19% (6/32) of patients preferred nothing. When combining the wand and nothing groups, 63% of patients preferred one of these two methods (95% exact CI: 44%–79%). Conclusion: There was no statistically significant difference in median pain experienced by patients during laryngeal botulinum toxin injection between these different analgesic modalities. More than half of the patients selected a preference for a technique that did not include lidocaine. This data supports individualization of analgesia during transcutaneous laryngeal injections. Level of Evidence: 2 Laryngoscope, 134:2277–2281, 2024 [ABSTRACT FROM AUTHOR]

Objectives: Adult‐onset idiopathic laryngeal dystonia (LD) can be associated with the risk of spread to muscles in the body. Subjects with extralaryngeal onset of dystonia have exhibited spread to the larynx. Previous studies analyze the spread of other dystonias but emphasis has not been placed on LD. The objective was to identify demographic and clinical factors contributing to the spread of dystonia to and from the larynx. Methods: Data were obtained from the Dystonia Coalition (DC)‐patients from 49 international clinical centers. Clinical and demographic data was taken from 143 out of 409 patients with diagnosed LD. Patient criteria included adult‐onset LD diagnosed on exam with no co‐morbid neurologic conditions and no dystonia in other locations. Results: Among the 143 patients, 94 (65.7%) patients were diagnosed with focal laryngeal onset, with the remainder having extralaryngeal onset. Family history and age at study were statistically significant indicators of a patient developing laryngeal versus extralaryngeal onset of dystonia. Among the laryngeal onset group, 21 cases (22.3%) had an average time of 5.81 ± 5.79 years to spread from diagnosis, most commonly to neck (61.9%). Among extralaryngeal onset patients, mean time of larynx spread was 7.92 ± 7.737 years, most commonly to neck (22.7%). Conclusions: Our data indicates approximately a quarter of patients with laryngeal‐onset dystonia will exhibit spread. There were no demographic or clinical factors that were statistically predictive of the likelihood of spread from larynx. Patients with dystonia elsewhere in the body should be counseled on the possibility of spread to larynx, and vice versa. Level of Evidence: 4 Laryngoscope, 134:2295–2299, 2024 [ABSTRACT FROM AUTHOR]

Abductor laryngeal dystonia (ABLD) is a rare neurological voice disorder which results in sporadic opening of the vocal folds during speech. Etiology is unknown, and to date there is no identified effective behavioral treatment for it. It is hypothesized that LSVT LOUD®, which was developed to treat dysphonia secondary to Parkinson's disease, may have application to speakers with ABLD to improve outcomes beyond that with botulinum neurotoxin (BoNT) treatment alone. The participant received one injection of BoNT in each vocal fold 2 to 3 months prior to initiating intensive voice therapy via teletherapy. Objective measures of vocal loudness (dB sound pressure level), maximum phonation time, and high/low pitch frequency (Hz) were recorded in all treatment sessions and follow-up sessions. Over the course of treatment, the participant showed steady gains in phonation time, volume, pitch range, and vocal quality with a substantial reduction in aphonic voice breaks by the end of the treatment program. Perceptual symptoms of ABLD were nearly undetectable by the participant and the clinicians up to 12 months posttreatment, with no additional BoNT injections. The results suggest that LSVT LOUD® following BoNT was effective, with long-lasting improvement in vocal function, for this speaker with ABLD. [ABSTRACT FROM AUTHOR]

Simple Summary: In this review, the endeavor is to compile the most significant findings related to the interconnection among various autonomic centers that regulate the autonomic activity of the central nervous system. These centers appear to play a crucial role in the control of vocal emissions in mammals, including humans. Specifically, the aim is to comprehend and delineate the intricate neural networks involved in this functional relationship. This will allow us to describe how these structures, traditionally associated with cardiorespiratory control, also play a crucial role in the regulation of vocalization. In humans, speech is a complex process that requires the coordinated involvement of various components of the phonatory system, which are monitored by the central nervous system. The larynx in particular plays a crucial role, as it enables the vocal folds to meet and converts the exhaled air from our lungs into audible sounds. Voice production requires precise and sustained exhalation, which generates an air pressure/flow that creates the pressure in the glottis required for voice production. Voluntary vocal production begins in the laryngeal motor cortex (LMC), a structure found in all mammals, although the specific location in the cortex varies in humans. The LMC interfaces with various structures of the central autonomic network associated with cardiorespiratory regulation to allow the perfect coordination between breathing and vocalization. The main subcortical structure involved in this relationship is the mesencephalic periaqueductal grey matter (PAG). The PAG is the perfect link to the autonomic pontomedullary structures such as the parabrachial complex (PBc), the Kölliker–Fuse nucleus (KF), the nucleus tractus solitarius (NTS), and the nucleus retroambiguus (nRA), which modulate cardiovascular autonomic function activity in the vasomotor centers and respiratory activity at the level of the generators of the laryngeal-respiratory motor patterns that are essential for vocalization. These cores of autonomic structures are not only involved in the generation and modulation of cardiorespiratory responses to various stressors but also help to shape the cardiorespiratory motor patterns that are important for vocal production. Clinical studies show increased activity in the central circuits responsible for vocalization in certain speech disorders, such as spasmodic dysphonia because of laryngeal dystonia. [ABSTRACT FROM AUTHOR]

Objectives: Laryngeal dystonia (LD) is characterized by irregular and involuntary task-specific spasms of the intrinsic laryngeal muscles. There is no curative treatment for it, however, laryngeal botulinum neurotoxin injections (BoNT-I) are considered the standard of care therapy. This study aims to characterize the population of LD patients and to assess the results of laryngeal BoNT-I. Methods: A Retrospective cohort study was conducted. Medical records were reviewed for all the patients with LD diagnosis seen in the Voice Unit of the Red de Salud UC Christus between January 2013 and October 2021. Biodemographic, clinical and treatment data were collected. Additionally, a telephonic survey was completed by the patients that underwent laryngeal BoNT-I, including self-reported voice outcomes and Voice Handicap Index 10 (VHI-10). Results: Of the 34 patients with LD included in the study, 23 received a total of 93 laryngeal BoNT-I and 19 completed the telephone survey. The majority (97%) of the injections corresponded to patients with adductor LD and 3% to abductor LD. Patients received a median of 3 (1–17) injections, with a more frequent cricothyroid approach (94.4%), while the thyrohyoid approach accounted for 5.6% of cases. Most injections were bilateral (96.8%). A significant improvement in the vocal quality and effort was noted after the last injection and the overall BoNT-I treatment (P < 0.001). Similarly, the VHI-10 score improved from a median of 31 (7–40) to 2 (0–19) (P < 0.001) after the last injection. A post-treatment breathy voice was reported in 95% of patients, and dysphagia to liquids and solids in 68% and 21%, respectively. Conclusions: Laryngeal BoNT-I is an effective treatment for LD, achieving an improvement in self-reported vocal quality and VHI-10 scores, and a reduction of the self-reported vocal effort. Adverse effects are mild in the majority of cases, constituting a safe and effective therapy for these patients. [ABSTRACT FROM AUTHOR]

Laryngeal dystonia is a debilitating disorder of voicing in which the laryngeal muscles are intermittently in spasm resulting in involuntary interruptions during speech. The central pathophysiology of laryngeal dystonia, underlying computational impairments in vocal motor control, remains poorly understood. Although prior imaging studies have found aberrant activity in the CNS during phonation in patients with laryngeal dystonia, it is not known at what timepoints during phonation these abnormalities emerge and what function may be impaired. To investigate this question, we recruited 22 adductor laryngeal dystonia patients (15 female, age range = 28.83-72.46 years) and 18 controls (eight female, age range = 27.40-71.34 years). We leveraged the fine temporal resolution of magnetoencephalography to monitor neural activity around glottal movement onset, subsequent voice onset and after the onset of pitch feedback perturbations. We examined event-related beta-band (12-30 Hz) and high-gamma-band (65-150 Hz) neural oscillations. Prior to glottal movement onset, we observed abnormal frontoparietal motor preparatory activity. After glottal movement onset, we observed abnormal activity in the somatosensory cortex persisting through voice onset. Prior to voice onset and continuing after, we also observed abnormal activity in the auditory cortex and the cerebellum. After pitch feedback perturbation onset, we observed no differences between controls and patients in their behavioural responses to the perturbation. But in patients, we did find abnormal activity in brain regions thought to be involved in the auditory feedback control of vocal pitch (premotor, motor, somatosensory and auditory cortices). Our study results confirm the abnormal processing of somatosensory feedback that has been seen in other studies. However, there were several remarkable findings in our study. First, patients have impaired vocal motor activity even before glottal movement onset, suggesting abnormal movement preparation. These results are significant because (i) they occur before movement onset, abnormalities in patients cannot be ascribed to deficits in vocal performance and (ii) they show that neural abnormalities in laryngeal dystonia are more than just abnormal responses to sensory feedback during phonation as has been hypothesized in some previous studies. Second, abnormal auditory cortical activity in patients begins even before voice onset, suggesting abnormalities in setting up auditory predictions before the arrival of auditory feedback at voice onset. Generally, activation abnormalities identified in key brain regions within the speech motor network around various phonation events not only provide temporal specificity to neuroimaging phenotypes in laryngeal dystonia but also may serve as potential therapeutic targets for neuromodulation.

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Background: There are several widely used clinical rating scales for documenting the severity and distribution of various types of dystonia. Objectives: The goal of this study was to evaluate the performance of the most commonly used scales in a large group of adults with the most common types of isolated dystonia. Methods: Global Dystonia Rating Scale (GDRS) and the Burke‐Fahn‐Marsden Dystonia Rating Scale (BFM) scores were obtained for 3067 participants. Most had focal or segmental dystonia, with smaller numbers of multifocal or generalized dystonia. These scales were also compared for 209 adults with cervical dystonia that had Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) scores and 210 adults with blepharospasm that had Blepharospasm Severity Scale (BSRS) scores. Results: There were strong correlations between the GDRS and BFM total scores (r = 0.79) and moderate correlations for their sub scores (r > 0.5). Scores for both scales showed positive skew, with an overabundance of low scores. BFM sub‐scores were not normally distributed, due to artifacts caused by the provoking factor. Relevant sub‐scores of the GDRS and BFM also showed moderate correlations with the TWSTRS (r > 0.5) for cervical dystonia and the BSRS (r > 0.5) for blepharospasm. Conclusions: The BFM is more widely used than the GDRS, but these results suggest the GDRS may be preferable for focal and segmental dystonias. The overabundance of very low scores for both scales highlights challenges associated with discriminating very mild dystonia from other abnormal movements or variants of normal behavior. [ABSTRACT FROM AUTHOR]

Laryngeal dystonia (LD), known or termed as spasmodic dysphonia, is a rare movement disorder with an unknown cause affecting the intrinsic laryngeal muscles. Neurophysiological studies point to perturbed inhibitory processes, while conventional genetic studies reveal fragments of genetic architecture in LD. The study's aims are to (1) describe transcranial magnetic stimulation (TMS) methodology for studying the functional integrity of the corticospinal tract by stimulating the primary motor cortex (M1) for laryngeal muscle representation and recording motor evoked potentials (MEPs) from laryngeal muscles; (2) evaluate the results of TMS studies investigating the cortical silent period (cSP) in LD; and (3) present the standard treatments of LD, as well as the results of new theoretical views and treatment approaches like repetitive TMS and laryngeal vibration over the laryngeal muscles as the recent research attempts in treatment of LD. Neurophysiological findings point to a shortened duration of cSP in adductor LD and altered cSP duration in abductor LD individuals. Future TMS studies could further investigate the role of cSP in relation to standard laryngological measures and treatment options. A better understanding of the neurophysiological mechanisms might give new perspectives for the treatment of LD. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to determine whether automated estimates of vocal creak would differentiate speakers with adductor laryngeal dystonia (AdLD) from speakers with muscle tension dysphonia (MTD) and speakers without voice disorders. Methods: Sixteen speakers with AdLD, sixteen speakers with MTD, and sixteen speakers without voice disorders were recorded in a quiet environment reading aloud a standard paragraph. An open‐source creak detector was used to calculate the percentage of creak (% creak) in each of the speaker's six recorded sentences. Results: A Kruskal‐Wallis one‐way analysis of variance revealed a statistically significant effect of group on the % creak with a large effect size. Pairwise Wilcoxon tests revealed a statistically significant difference in % creak between speakers with AdLD and controls as well as between speakers with AdLD and MTD. Receiver operating characteristic curve analyses indicated that % creak differentiated AdLD from both controls and speakers with MTD with high sensitivity and specificity (area under the curve statistics of 0.94 and 0.86, respectively). Conclusion: Percentage of creak as calculated by an automated creak detector may be useful as a quantitative indicator of AdLD, demonstrating the potential for use as a screening tool or to aid in a differential diagnosis. Level of Evidence: 3 Laryngoscope, 133:2687–2694, 2023 [ABSTRACT FROM AUTHOR]

This postmarketing surveillance study was conducted to evaluate the safety and effectiveness of onabotulinumtoxinA in Japanese patients with laryngeal dystonia (LD). Patients receiving onabotulinumtoxinA for the first time were enrolled and observed for up to 12 months following the first injection. Safety assessment included adverse drug reactions (ADRs), and effectiveness assessments included the Voice Handicap Index-10 (VHI-10) and physician's global assessment (PGA). ADRs were observed in 48 (5.8%) of 834 patients in the safety analysis set, including dysphonia in 43 (5.2%) patients and dysphagia in 7 (0.8%) patients. The change in total VHI-10 score (mean) in 790 patients included in the effectiveness analysis set showed that improvement in adductor LD peaked at 2 months after the first injection, while patients with abductor or mixed LD showed a gradual attenuation of effect 2–4 weeks post-injection. The change in total VHI-10 score in subsequent injections was generally similar to that following the first injection. The overall effectiveness rate according to the PGA was 93.4% (738/790 patients). The results demonstrate that onabotulinumtoxinA is a well-tolerated and effective treatment for LD in real-world clinical practice. [ABSTRACT FROM AUTHOR]

Background/Objectives: Laryngeal sensory abnormality has been implicated as a component of adductor laryngeal dystonia (AdLD). The study objective was to assess laryngopharyngeal sensation in AdLD utilizing a calibrated, tactile aesthesiometer to deliver differential stimuli to lateral pyriform sinus (LPS), aryepiglottic fold (AEF), and false vocal fold (FVF). Methods: Patients with known Botox‐responsive AdLD underwent sensory testing using a previously‐validated methodology involving calibrated tactile stimuli (6–0, 5–0, 4.5–0, 4–0 nylon monofilaments). Laryngeal adductor reflex (LAR) and participant‐rated perceptual strength of stimulI were evaluated. Responses were compared to normative controls (n = 33). Two‐samples, Mann–Whitney and Fisher exact tests compared mean strength ratings and LAR between AdLD and control groups. Mixed‐effects logistic regression and linear models assessed association of filament size, stimulus site, age, sex, and LD status on LAR and perceptual strength rating respectively. Results: Thirteen AdLD patients (nine women, mean age 60+/−15 years) completed testing. Average LAR response rates were higher amongst all filament sizes in AdLD versus controls at LPS (56.3% vs. 35.7%) and AEF (96.1% vs. 70.2%) with comparable rates at FVF (90.2% vs. 91.7%). AdLD had 3.3 times the odds of observed LAR compared to controls (p = 0.005), but differences in subjective detection of stimuli, perceptual strength ratings, and cough/gag rates were insignificant on multivariate modeling (p > 0.05). Conclusions: This is the first study to objectively assess laryngopharyngeal sensation in AdLD. Findings demonstrated increased laryngopharyngeal sensation in AdLD compared to controls. The identification of increased laryngeal hypersensitivity in these patients may improve understanding of AdLD pathophysiology and identify future targets for intervention. Level of Evidence: 2 Laryngoscope, 133:2271–2278, 2023 [ABSTRACT FROM AUTHOR]

The cortical silent period (cSP) is a period of electrical silence following a motor-evoked potential (MEP) in the electromyographic signal recorded from a muscle. The MEP can be elicited by transcranial magnetic stimulation (TMS) over the primary motor cortex site corresponding with the muscle. The cSP reflects the intracortical inhibitory process mediated by GABAA and GABAB receptors. The study aimed to investigate the cSP in the cricothyroid (CT) muscle after applying e-field-navigated TMS over the laryngeal motor cortex (LMC) in healthy subjects. Then, a cSP as a neurophysiologic feature for laryngeal dystonia was observed. We applied a single-pulse e-field-navigated TMS to the LMC over both hemispheres with hook-wire electrodes positioned in the CT muscle in nineteen healthy participants, which triggered the elicitation of contralateral and ipsilateral corticobulbar MEPs. The subjects were engaged in a vocalization task, and then we assessed the following metrics: LMC intensity, peak-to-peak MEP amplitude in the CT muscle, and cSP duration. The results showed that the cSP duration from the contralateral CT muscle was distributed from 40 ms to 60.83 ms, and from the ipsilateral CT muscle, from 40 ms to 65.58 ms. Also, no significant difference was found between the contralateral and ipsilateral cSP duration (t(30) = 0.85, p = 0.40), MEP amplitude in the CT muscle (t(30) = 0.91, p = 0.36), and LMC intensity (t(30) = 1.20, p = 0.23). To conclude, the applied research protocol showed the feasibility of recording LMC corticobulbar MEPs and observing the cSP during vocalization in healthy participants. Furthermore, an understanding of neurophysiologic cSP features can be used to study the pathophysiology of neurological disorders that affect laryngeal muscles, such as laryngeal dystonia. [ABSTRACT FROM AUTHOR]

Laryngeal dystonia is a potentially disabling task specific dystonia primarily affecting speech. The evaluation and diagnosis of laryngeal dystonia remain challenging, and often require a multi‐disciplinary approach, involving collaboration among speech language pathologists, neurologists and laryngologists (1–5). It is crucial to correctly differentiate between the types of laryngeal dystonia due to the distinct therapeutic approaches and responses to botulinum toxin therapy or speech therapy. For educational purposes, we have divided laryngeal dystonia into two main types: adductor and abductor dystonia. In this article, we describe a series of examination techniques that can assist movement disorders neurologists diagnosing this condition, and appropriately differentiating the most common forms of laryngeal dystonia. [ABSTRACT FROM AUTHOR]

Spasmodic dysphonia (SD) is considered a rare focal laryngeal dystonia characterized by task-specific voice dysfluency resulting from selective intrinsic laryngeal musculature hyperfunction. Symptoms may be attenuated by a sensory trick. Although SD can be seen at times in generalized dystonia syndrome, it is typically a sporadic phenomenon, and the involvement of the laryngeal adductor muscles is more common than that of the abductor muscles. This research reviews the literature for the pathogenesis, clinical characteristics, treatment options, and current management methods of SD. Technological advances have enabled clinicians to better understand the connection between laryngeal function and dysfunction. Refinements in imaging and genetic investigation techniques have helped better understand the underlying mechanisms of this neurolaryngology disorder. Currently, the standard of care for SD is the symptomatic management of botulinum toxin (BT) chemodenervation. This is supported by a large body of literature attesting to its efficacy in many different research studies, particularly in the uncomplicated adductor form of the disorder. Efforts towards surgical treatment predate the development of BT treatment by a decade, but the long-term efficacy has not been proven and, further research is expected. Symptom relief in patients with abductor SD and dystonia with tremors after surgical and BT treatments and those in patients remains suboptimal. [ABSTRACT FROM AUTHOR]

Laryngeal dystonia (LD), or spasmodic dysphonia (SD), is a chronic, task-specific, focal movement disorder affecting the larynx. It interferes primarily with the essential functions of phonation and speech. LD affects patients' ability to communicate effectively and significantly diminishes their quality of life. Botulinum neurotoxin was first used as a therapeutic agent in the treatment of LD four decades ago and remains the standard of care for the treatment of LD. This article provides an overview of the clinical application of botulinum neurotoxin in the management of LD, focusing on the classification for this disorder, its pathophysiology, clinical assessment and diagnosis, the role of laryngeal electromyography and a summary of therapeutic injection techniques, including a comprehensive description of various procedural approaches, recommendations for injection sites and dosage considerations. [ABSTRACT FROM AUTHOR]

Focal laryngeal dystonia (LD) is a rare, idiopathic disease affecting the laryngeal musculature with an unknown cause and clinically presented as adductor LD or rarely as abductor LD. The most effective treatment options include the injection of botulinum toxin (BoNT) into the affected laryngeal muscle. The aim of this narrative review is to summarize the patho-neuro-physiological and genetic background of LD, as well as the standard recommended therapy (BoNT) and pharmacological treatment options, and to discuss possible treatment perspectives using neuro-modulation techniques such as repetitive transcranial magnetic stimulation (rTMS) and vibrotactile stimulation. The review will present two LD cases, patients with adductor and abductor LD, standard diagnostic procedure, treatments and achievement, and the results of cortical excitability mapping the primary motor cortex for the representation of the laryngeal muscles in the assessment of corticospinal and corticobulbar excitability. [ABSTRACT FROM AUTHOR]

Abstract Objectives This study characterized the clinical phenotypes of individuals with vocal tremor (VT) using tremor classification criteria published by the International Parkinson and Movement Disorder Society (IPMDS) including laryngeal features from the American Academy of Otolaryngology—Head and Neck Surgery (AAO‐HNS). Methods VT phenotypic descriptors were extracted from participant medical records from 2017 to 2019. Clinical phenotype descriptors included the: (a) chief complaint and discipline for the first appointment, (b) demographics, (c) tremor body distribution, condition, frequency, and progression, (d) exacerbating/alleviating factors, (e) treatment approaches, and (g) neurologic comorbidities. Descriptive statistics were conducted. Results Of 179 meeting inclusion criteria, 2/3 were female; tremor onset affected voice (43%) or extremity (32%) and 2/3 were documented with tremor duration of 3 years or more. Those with primary VT first saw otolaryngology or speech language pathology (59%), whereas those with primary extremity/head tremor first saw neurology (36%). Documentation commonly omitted tremor clinical features such as (a) observed conditions of tremor (64%), (b) laryngeal features (64%), and (c) tremor frequency (92%). Thus, VT classification was based on comorbidity in 49% of patients (ie, essential tremor (48%), dystonia (72%), and Parkinson's disease (100%)) and 32% had inadequate documentation to classify. Conclusion The majority of individuals with VT were unable to be classified based on documented clinical features highlighting the need for consistent multidisciplinary assessment of tremor affecting speech structures. The primary site of tremor determined the first discipline seen. Most commonly classified VT categories included essential tremor (47%), dystonia (28%), Parkinsonism (7%), and isolated VT (19%). Level of Evidence 4.

Laryngeal Botulinum Toxin injection (LBTX) in the adductor musculature is the current therapy for Adductor Spasmodic Dysphonia. This study explores nonbiological factors that can affect the patient experience during this procedure and their association with better or worse self-reported effectiveness. A 14 item survey was used to evaluate the patient experience in patients who had undergone LBTX in Mayo Clinic Jacksonville, Florida, during 2019. Information from the survey, previous medical history, and demographic data were collected, and a descriptive analysis was performed. Of the 36 patients who participated, the mean age was 65 years and a female predominance was found (66%). The average age at onset of symptoms was 57 years, and voice tremor was associated with 36.1% of patients. Preprocedure education was recognized as a factor affecting outcomes in 87% of patients; 11 patients reported that body position used during the injection could affect the results. Pain or stress experienced at the time of procedure was referred in one-third of patients as an influencing factor too. This study has shown that nonpharmacological factors such as education before the procedure, body position, pain, and stress sensation before LBTX may have a role in the botulinum toxin effect on Adductor Spasmodic Dysphonia patients. This study is the first to describe these variables qualitatively, and further studies may help to improve the patient experience and outcome of LBTX around the world. [ABSTRACT FROM AUTHOR]

Objective: Non-motor symptoms (NMS) have been identified in some focal adult-onset dystonia. In the present study we aimed to evaluate the presence of NMS in patients with spasmodic dysphonia (SD), a focal action-induced dystonia that affects intrinsic laryngeal muscle control.Methods: Seventeen SD patients and 17 control subjects not significantly different in age and sex were evaluated for the presence of NMS. Additionally, voice handicap index (VHI-10), reflux symptom index, neuropsychiatric symptoms and QoL were assessed by validated scales and questionnaires.Results: Patients' group significantly differed from control group in mild depressive symptoms (4.35 ± 3.9 vs. 1.47 ± 2; p=0.01), insomnia (35.3% vs. 14.7%; p=0.016), smell and taste loss (11.8% vs. 0%; p=0.033), swallowing difficulties (17.6% vs. 0%; p=0.007) and throat pain (17.6% vs. 0%; p=0.007). In the group of SD, there was no correlation between voice perception evaluated by VHI-10, number of NMS or QoL.Conclusion: Patients with SD have a greater burden of depressive, smell, taste, and sleep NMS than control subjects. [ABSTRACT FROM AUTHOR]

Laryngeal botulinum toxin injection is an important treatment modality for spasmodic dysphonia and other laryngeal disorders. We sought to compare usage patterns of laryngeal botulinum toxin injections for voice disorders and to identify and quantify inefficiencies and barriers in providing this treatment. A 26 item survey was written and approved for distribution by the American Academy of Otolaryngology-Head and Neck Surgery and the National Spasmodic Dysphonia Association. It was distributed to Otolaryngologists who perform laryngeal botulinum toxin injections via the e-mail lists of the National Spasmodic Dysphonia Association provider database, American Academy of Otolaryngology-Head and Neck Surgery Voice Committee and the American Laryngological Association Neurolaryngology Study Group. There were 81 survey participants who collectively reported performing >1700 laryngeal botulinum toxin injections for voice disorders monthly (Mean = 21.5 pts/month). Regarding botulinum toxin A (BtxA) vial use, 54% of participants reported using multiple doses per vial for different patients during a single clinic day, while 14% reported using pharmacy predrawn single use aliquots. A combination of usage practices was reported by 7% of participants. Using an individual vial per patient and discarding the unused remainder was reported by 26% of participants with an associated annual cost in wasted BtxA of $84,300 per physician. There is wide variation in injection practices regarding management of BtxA vials and adherence to an individual vial per patient policy is associated with significant waste of health care resources. Alternative approaches to BtxA vial use could positively impact health care resource utilization. [ABSTRACT FROM AUTHOR]

Background: Laryngeal dystonia (LD), or spasmodic dysphonia (SD), is a neurological disorder characterized by focal dystonia or involuntary spasms of the laryngeal muscles and associated voice symptoms. It is typically treated with injection of botulinum toxin (BoNT) that weakens the affected muscles. Aims: The primary purpose of this qualitative study was to explore participants' experience of living with LD and BoNT treatment. The secondary purpose was to examine those experiences as a function of participants' scores on the Communicative Participation Item Bank (CPIB). Results will enhance our understanding of restrictions in communicative participation, assist in planning intervention targeting these restrictions and aid in clinical interpretation of CPIB scores. Methods & Procedures: Semi‐structured interviews using a phenomenological tradition and focusing on BoNT treatment and communicative participation were conducted with 26 people with LD who are on established BoNT treatment regimens. Interviews were recorded, transcribed, coded and analysed inductively. Participants were categorized by CPIB scores into groups ranging from none to extensive participation restrictions. Both self‐ and expert ratings of voice were obtained. Outcomes & Results: Participants with different levels of CPIB scores had different experiences related to communicative participation in the context of BoNT treatment. These differences were organized into the following topics: BoNT and voice; attitudes toward participation; coping strategies; and advice. For all participants except those in the least restricted and most restricted groups, expert ratings of voice did not relate to CPIB scores. Conclusions & Implications: Although most participants report improved voice with BoNT treatment, many participants experienced lingering restrictions in communicative participation, some to a severe extent. Participants reported coping with these restrictions in many ways; some of these strategies were more successful than others. Those with restricted participation recommended more support for daily life and the emotional toll of LD, as well as support for family members. This support might be offered by speech–language pathologists. What this paper adds: What is already known on the subject: Participants with different levels of CPIB scores had different experiences related to communicative participation in the context of BoNT treatment. What this study adds to the existing knowledge: Although most participants report improved voice with BoNT treatment, many participants experienced lingering restrictions in communicative participation, some to a severe extent. What are the potential or actual clinical implications of this work?: SLP services that take a participation‐focused approach to intervention and use multi‐factorial approaches to help clients maximize their life participation in the context of LD are well within the SLP scope of practice. SLPs can help clients find and use their optimal voices within the constraints of the dystonia and BoNT effects. [ABSTRACT FROM AUTHOR]

We aimed to study the attitude of Italian neurologists in the use of conventional MRI in patients with idiopathic adult-onset focal dystonia. Patients were included in the Italian Dystonia Registry by experts working in different Italian centers. MRI was available for 1045 of the 1471 (71%) patients included in the analysis. Using logistic regression analysis, we found that MRI was more likely to be performed in patients with cervical dystonia, spasmodic dysphonia, or non-task-specific upper limb dystonia, whereas it was less likely to be performed in patients with blepharospasm or task-specific upper limb dystonia. We did not find differences in the number of MRIs performed between neurological centers in Northern, Central, and Southern Italy. We conclude that although the diagnosis of idiopathic adult-onset dystonia is mainly based on clinical grounds, many movement disorder experts rely on MRI to confirm a diagnosis of idiopathic dystonia. We suggest that neuroimaging should be used in patients with adult-onset focal dystonia to rule out secondary forms. [ABSTRACT FROM AUTHOR]

Dystonia is a movement disorder characterized by sustained or intermittent muscle contractions causing abnormal postures, repetitive movements, or both. Research in dystonia has been challenged by several factors. First, dystonia is uncommon. Dystonia is not a single disorder but a family of heterogenous disorders with varied clinical manifestations and different causes. The different subtypes may be seen by providers in different clinical specialties including neurology, ophthalmology, otolaryngology, and others. These issues have made it difficult for any single center to recruit large numbers of subjects with specific types of dystonia for research studies in a timely manner. The Dystonia Coalition is a consortium of investigators that was established to address these challenges. Since 2009, the Dystonia Coalition has encouraged collaboration by engaging 56 sites across North America, Europe, Asia, and Australia. Its emphasis on collaboration has facilitated establishment of international consensus for the definition and classification of all dystonias, diagnostic criteria for specific subtypes of dystonia, standardized evaluation strategies, development of clinimetrically sound measurement tools, and large multicenter studies that document the phenotypic heterogeneity and evolution of specific types of dystonia.

Dystonia is a movement disorder characterized by sustained or intermittent muscle contractions causing abnormal postures, repetitive movements, or both. Research in dystonia has been challenged by several factors. First, dystonia is uncommon. Dystonia is not a single disorder but a family of heterogenous disorders with varied clinical manifestations and different causes. The different subtypes may be seen by providers in different clinical specialties including neurology, ophthalmology, otolaryngology, and others. These issues have made it difficult for any single center to recruit large numbers of subjects with specific types of dystonia for research studies in a timely manner. The Dystonia Coalition is a consortium of investigators that was established to address these challenges. Since 2009, the Dystonia Coalition has encouraged collaboration by engaging 56 sites across North America, Europe, Asia, and Australia. Its emphasis on collaboration has facilitated establishment of international consensus for the definition and classification of all dystonias, diagnostic criteria for specific subtypes of dystonia, standardized evaluation strategies, development of clinimetrically sound measurement tools, and large multicenter studies that document the phenotypic heterogeneity and evolution of specific types of dystonia. [ABSTRACT FROM AUTHOR]

Background: Despite use of qualitative laryngeal electromyography (LEMG) guided botulinum toxin A (BoNT‐A) injection for treatment of adductor spasmodic dysphonia (AdSD), unsatisfactory injections and complete "misses" remain problematic. We aimed to determine if the quantitative LEMG measure of number of small segments (NSS) correlates with voice outcomes following (BoNT‐A injection for AdSD. Methods: Automated quantitative LEMG analysis was performed during electromyography (EMG) ‐guided BoNT‐A injection into the thyroarytenoid‐lateral cricoarytenoid muscle complex for treatment of AdSD. Pre‐injection phonatory NSS values were correlated with clinical voice outcomes and patient reported injection results. Results: Quantitative LEMG measures were obtained for 45 AdSD patients (28 female, mean age 60.8 ± 12.8 years) during EMG‐guided BoNT‐A injection. Mean sampled NSS during phonation immediately prior to BoNT‐A injection was 524 ± 323 (range: 2–904). Mean follow up was 36.5 ± 9.4 days; one patient was lost to follow‐up. In comparison to their previous BoNT‐A injection, the current injection was rated as worse, same, and better by 13 (29.5%), 25 (56.8%), and 6 (13.6%) patients, respectively. All 4 (9.1%) patients with NSS < 200 rated their BoNT‐A injection result as worse than previous, and change in Voice Handicap Index‐10 (VHI‐10) scores were worse or without change. Conclusions: Aiming for an NSS value greater than 200 during phonation prior to BoNT‐A toxin injection for AdSD may reduce unfavorable voice outcomes. [ABSTRACT FROM AUTHOR]

Objectives: Current patient‐reported outcome measures do not adequately capture the impact of spasmodic dysphonia (SD) on communication in daily life situations. The aim of this study was to validate the Communicative Participation Item Bank (CPIB), which specifically measures a disease's impact on daily conversational situations, as an outcome measure for SD. Study Design: Multi‐institutional prospective cohort study. Methods: A prospective study was conducted with administration of the 46‐question CPIB and the Voice Handicap Index‐10 (VHI‐10) to 190 participants with SD before (time 1) and 6 weeks after (time 2) botulinum toxin injection. Differential item function (DIF) analyses were performed to examine potential item bias. Paired t‐tests were used to assess change in each of the CPIB and VHI‐10 scores after treatment. Pearson correlations were calculated between the CPIB and VHI‐10. Results: DIF analyses revealed no clinically meaningful difference between the item parameters generated for this SD sample and the original CPIB calibration sample. There were statistically significant changes between the pre‐treatment and post‐treatment time points for both the CPIB and VHI‐10. Correlations between the CPIB and VHI were moderate‐high. Conclusions: The CPIB item bank, General Short Form, and scoring parameters can be used with people with SD for valid and reliable measurement of the impact of communication disorders on communication in everyday life. The CPIB is sensitive to changes with intervention, proving useful for clinical and research purposes to assess the efficacy and effectiveness of interventions. Level of Evidence: Level 2, prospective observational research with an experimental design (ie, cohort study). Laryngoscope, 131:859–864, 2021 [ABSTRACT FROM AUTHOR]

Objectives: This study characterized the clinical phenotypes of individuals with vocal tremor (VT) using tremor classification criteria published by the International Parkinson and Movement Disorder Society (IPMDS) including laryngeal features from the American Academy of Otolaryngology—Head and Neck Surgery (AAO‐HNS). Methods: VT phenotypic descriptors were extracted from participant medical records from 2017 to 2019. Clinical phenotype descriptors included the: (a) chief complaint and discipline for the first appointment, (b) demographics, (c) tremor body distribution, condition, frequency, and progression, (d) exacerbating/alleviating factors, (e) treatment approaches, and (g) neurologic comorbidities. Descriptive statistics were conducted. Results: Of 179 meeting inclusion criteria, 2/3 were female; tremor onset affected voice (43%) or extremity (32%) and 2/3 were documented with tremor duration of 3 years or more. Those with primary VT first saw otolaryngology or speech language pathology (59%), whereas those with primary extremity/head tremor first saw neurology (36%). Documentation commonly omitted tremor clinical features such as (a) observed conditions of tremor (64%), (b) laryngeal features (64%), and (c) tremor frequency (92%). Thus, VT classification was based on comorbidity in 49% of patients (ie, essential tremor (48%), dystonia (72%), and Parkinson's disease (100%)) and 32% had inadequate documentation to classify. Conclusion: The majority of individuals with VT were unable to be classified based on documented clinical features highlighting the need for consistent multidisciplinary assessment of tremor affecting speech structures. The primary site of tremor determined the first discipline seen. Most commonly classified VT categories included essential tremor (47%), dystonia (28%), Parkinsonism (7%), and isolated VT (19%). Level of Evidence: 4. [ABSTRACT FROM AUTHOR]

Adductor spasmodic dysphonia is an extremely disabling voice disorder that negatively impacts a patient's quality of life (QOL). We performed a systematic review to determine if Botulinum Toxin (BT) injections improved voice related QOL in patients with this disorder. PubMed, EMBASE, Web of Science, Cochrane Library, ProQuest, and Scopus from 2000, to and including November 1st, 2018, were searched. We identified randomized controlled trials, controlled trials, and observational studies of the effects of BT injections on the QOL in patients with adductor spasmodic dysphonia. The two authors, separately and individually chose the studies based on inclusion criteria, assessed study quality, and relevant extracted data. Nine studies used the Voice Handicap Index (VHI). The results showed significant changes pre- to post-BT injection (SMD = −0.357; 95% CI: −0.579, −0.136; z = 3.16; P = 0.002; I-squared = 0.000%). Five studies used the Voice-Related QOL; their results also showed a significant improvement pre- to postinjection (SMD = −2.99; 95% CI: −3.27, −1.32; z = 4.61; P < 0.001; I-squared = 87%). Three other studies used other, shortened versions of the VHI, VHI-10. They also showed significant results (SMD = −0.145; 95% CI: −0.349, 0.06; z = 1.38; P = 0.17; I-squared = 0.000). BT injections positively affect patients' QOL. However, patients' QOL scores may never be normalized, in line with perceptual voice quality and acoustic parameters. [ABSTRACT FROM AUTHOR]

Background: Dyspnoea is rarely mentioned in the clinical description of adult-onset isolated dystonia. In this study, we present the clinical features of 13 patients with Meige syndrome (cranio-cervical dystonia) with breathing difficulties. Methods: A retrospective case note review was performed of patients presenting with Meige syndrome and shortness of breath, to a neuro-laryngology MDT clinic. Results: Some patients were severely limited by their breathlessness, but others did not volunteer these symptoms. The majority of patients were referred with the assumption that the larynx was the cause of the problem; however half the patients did not have evidence of laryngeal involvement. Of the patients who had laryngeal involvement, injecting the larynx alone did not always relieve the dyspnoea. The majority of our patients responded to injection of the suprahyoid muscles, including genioglossus, digastric and mylohyoid. Conclusion: We recommend routinely establishing if the patient with Meige syndrome has signs or symptoms of breathlessness, and establishing the level of the problem, as this can be treated successfully.

The syndromology of dysfunction of the vocal cords varies widely from the absence of symptoms to mild shortness of breath to acute respiratory disfunction, which can mimic an asthma attack. The treatment of vocal dysfunction and bronchial asthma is different. An early fold diagnosis of vocal dysfunction can prevent improper treatment and, therefore, minimize the rising costs of health care.

The emerging view of dystonia is that of a large‐scale functional network disorder, in which the communication is disrupted between sensorimotor cortical areas, basal ganglia, thalamus, and cerebellum. The structural underpinnings of functional alterations in dystonia are, however, poorly understood. Notably, it is unclear whether structural changes form a larger‐scale dystonic network or rather remain focal to isolated brain regions, merely underlying their functional abnormalities. Using diffusion‐weighted imaging and graph theoretical analysis, we examined inter‐regional white matter connectivity of the whole‐brain structural network in two different forms of task‐specific focal dystonia, writer's cramp and laryngeal dystonia, compared to healthy individuals. We show that, in addition to profoundly altered functional network in focal dystonia, its structural connectome is characterized by large‐scale aberrations due to abnormal transfer of prefrontal and parietal nodes between neural communities and the reorganization of normal hub architecture, commonly involving the insula and superior frontal gyrus in patients compared to controls. Other prominent common changes involved the basal ganglia, parietal and cingulate cortical regions, whereas premotor and occipital abnormalities distinctly characterized the two forms of dystonia. We propose a revised pathophysiological model of focal dystonia as a disorder of both functional and structural connectomes, where dystonia form‐specific abnormalities underlie the divergent mechanisms in the development of distinct clinical symptomatology. These findings may guide the development of novel therapeutic strategies directed at targeted neuromodulation of pathophysiological brain regions for the restoration of their structural and functional connectivity. [ABSTRACT FROM AUTHOR]

Objectives: Alterations in sensory discrimination are a prominent nonmotor feature of dystonia. Abnormal temporal discrimination in focal dystonia is considered to represent its mediational endophenotype, albeit unclear pathophysiological correlates. We examined the associations between the visual temporal discrimination threshold (TDT) and brain activity in patients with musician's dystonia, nonmusician's dystonia, and healthy controls.Methods: A total of 42 patients and 41 healthy controls participated in the study. Between-group differences in TDT z scores were computed using inferential statistics. Statistical associations of TDT z scores with clinical characteristics of dystonia and resting-state functional brain activity were examined using nonparametric rank correlations.Results: The TDT z scores of healthy controls were significantly different from those of patients with nonmusician's dystonia, but not of patients with musician's dystonia. Healthy controls showed a significant relationship between normal TDT levels and activity in the inferior parietal cortex. This relationship was lost in all patients. Instead, TDT z scores in musician's dystonia established additional correlations with activity in premotor, primary somatosensory, ventral extrastriate cortices, inferior occipital gyrus, precuneus, and cerebellum, whereas nonmusician's dystonia showed a trending correlation in the lingual gyrus extending to the cerebellar vermis. There were no significant relationships between TDT z scores and dystonia onset, duration, or severity.Conclusions: TDT assessment as an endophenotypic marker may only be relevant to nonmusician forms of dystonia because of the lack of apparent alterations in musician's dystonia. Compensatory adaptation of neural circuitry responsible for TDT processing likely adjusted the TDT performance to the behaviorally normal levels in patients with musician's dystonia, but not nonmusician's dystonia. © 2020 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

This systematic review aims to identify instruments used to evaluate treatment outcomes for people with spasmodic dysphonia. Electronic database (PubMed, Cochrane Library, Embase, and CINAHL) searches and hand-searching identified studies that evaluated treatment approaches for spasmodic dysphonia which included pre and post outcome data. A total of 4714 articles were retrieved from searching databases; 1165 were duplicates. Titles and abstracts of 3549 were screened, with 171 being selected for full-text review. During full-text review, 101 articles were deemed suitable for inclusion. An additional 24 articles were identified as suitable for inclusion through hand-searching of reference lists. Data was extracted from 125 studies, identifying 220 outcome measures. As per the World Health Organization's International Classification of Functioning (ICF), the majority measured body functions (n = 212, 96%). Outcomes that explored communication and participation in everyday life and attitudes towards communication (ie, activity and participation domains) were infrequent (n = 8; 4%). Quality of life, a paradigm outside of the scope of the ICF, was also captured by four outcome measures. No instruments evaluating communication partners' perspectives were identified. Currently there is no unified approach to the measurement of outcomes in SD treatment research. Development and implementation of a core outcome set is recommended to facilitate improved understanding of the efficacy of current and new treatment options. [ABSTRACT FROM AUTHOR]

Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective treatment for motor features in Parkinson's disease (PD). We present the case of a 56-year-old man with a 17-year history of PD. He underwent bilateral STN-DBS at the age of 51 years because of troublesome dyskinesia and wearing off. His motor features dramatically improved after the operation; however, he developed dysarthria and a refractory wheeze associated with dyspnea due to abnormal hyperadduction of the false vocal fold. By adjusting the stimulation site of STN, his severe wheeze, which was considered to be the result of the unfavorable spread of current to the corticobulbar tract, was significantly improved. This report provides concrete evidence that wheezing is caused by hyperadduction of the false vocal fold as an adverse effect of STN-DBS and can be reversed by adjusting the stimulation site for STN-DBS.

Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective treatment for motor features in Parkinson's disease (PD). We present the case of a 56-year-old man with a 17-year history of PD. He underwent bilateral STN-DBS at the age of 51 years because of troublesome dyskinesia and wearing off. His motor features dramatically improved after the operation; however, he developed dysarthria and a refractory wheeze associated with dyspnea due to abnormal hyperadduction of the false vocal fold. By adjusting the stimulation site of STN, his severe wheeze, which was considered to be the result of the unfavorable spread of current to the corticobulbar tract, was significantly improved. This report provides concrete evidence that wheezing is caused by hyperadduction of the false vocal fold as an adverse effect of STN-DBS and can be reversed by adjusting the stimulation site for STN-DBS. [ABSTRACT FROM AUTHOR]

Introduction: Spasmodic dysphonia (SD) is an isolated focal dystonia characterized by laryngeal spasms during voluntary voice production. Environmental factors have been assumed to play a role in SD pathophysiology; however, the exact extrinsic risk factors and their association with neural alterations remain unknown.Methods: A total of 186 SD patients and 85 healthy controls completed a structured 177-question survey, consisting of questions on general biographical information, medical history, symptomatology of dystonia. Data were imputed in a stepwise regression model to identify extrinsic risk factors for SD. In addition, functional MRI data from a subset of this cohort were analyzed to determine brain activation abnormalities associated with the SD extrinsic risk.Results: We found that (1) recurrent upper respiratory infections, gastroesophageal reflux, and neck trauma, all of which influence sensory feedback from the larynx, represent extrinsic risk factors, likely triggering the manifestation of SD symptoms, and (2) neural alterations in the regions necessary for sensorimotor preparation and integration are influenced by an extrinsic risk in susceptible individuals.Conclusions: These findings provide evidence for the extrinsic risk in SD development and demonstrate the link with alterations in the sensorimotor preparatory network that collectively contribute to the multifactorial pathophysiology of SD. [ABSTRACT FROM AUTHOR]

Objective: Spasmodic dysphonia (SD) is a neurological disorder characterized by involuntary spasms in the laryngeal muscles. It is thought to selectively affect speaking; other vocal behaviors remain intact. However, the patients' own perspective on their symptoms is largely missing, leading to partial understanding of the full spectrum of voice alterations in SD.Methods: A cohort of 178 SD patients rated their symptoms on the visual analog scale based on the level of effort required for speaking, singing, shouting, whispering, crying, laughing, and yawning. Statistical differences between the effort for speaking and the effort for other vocal behaviors were assessed using nonparametric Wilcoxon rank-sum tests within the overall SD cohort as well as within different subgroups of SD.Results: Speech production was found to be the most impaired behavior, ranking as the most effortful type of voice production in all SD patients. In addition, singing required nearly similar effort as speaking, ranking as the second most altered vocal behavior. Shouting showed a range of variability in its alterations, being especially difficult to produce for patients with adductor form, co-occurring voice tremor, late onset of disorder, and familial history of dystonia. Other vocal behaviors, such as crying, laughing, whispering, and yawning, were within the normal ranges across all SD patients.Conclusion: Our findings widen the symptomatology of SD, which has predominantly been focused on selective speech impairments. We suggest that a separation of SD symptoms is rooted in selective aberrations of the neural circuitry controlling learned but not innate vocal behaviors.Level Of Evidence: 4 Laryngoscope, 129:1627-1633, 2019. [ABSTRACT FROM AUTHOR]

Introduction:Dystonia is a disorder of movement caused by various etiologies. Laryngeal dystonia is caused by the spasm of laryngeal muscles. It is a disorder caused by vocal fold movement in which excessive adduction or abduction of the vocal folds occurs during speech. The pathophysiology of this type of dystonia is not fully known. Some researchers have suggested that basal ganglia structures and their connections with cortical areas have been involved in the pathogenesis of dystonia. Case Report:In this paper a 7.5-year-old boy suffering from laryngeal dystonia with bilateral lesions in Globus Pallidus is presented. The patient also suffered from swallowing problems, monotone voice, vocal tremor, hypersensitivity of gag reflex, and stuttering. Drug treatment failed to cure him; therefore, he was referred to rehabilitation therapy. Conclusion:In conclusion, special attention should be brought upon laryngeal dystonia, especially in patients showing Extra-pyramidal symptoms and/or abnormalities of the basal ganglia. In children, laryngeal dystonia may be potentially fatal. Lack of consideration for this condition during rehabilitation therapy can lead to serious consequences for a child.