An observational study in Laryngeal Dystonia, Spasmodic Dysphonia and Tremor, sponsored by Massachusetts Eye and Ear Infirmary. Recruiting at 1 site in United States. Open to participants aged 18 Years to 80 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-12-02.
Sponsored by Massachusetts Eye and Ear Infirmary · Observational
The researchers will systematically evaluate current and novel clinical voice assessment tools and measures to elucidate distinct clinical phenotypes of those with laryngeal dystonia and voice tremor.
Focal laryngeal dystonia (LD) is a rare neurological voice disorder that interrupts speaking with the intermittent onset of strained-strangled voice quality or causes voicing to stop or produce sudden breathiness. Those suffering from LD commonly report the onset of symptoms 5 years prior to achieving an accurate diagnosis, despite seeing multiple experts. Voice tremor (VT) is another neurological voice disorder that is perceived by listeners as shaky voice quality. Severe VT can result in voice interruptions that sound similar to LD resulting in misdiagnosis by experts. Recent research shows poor reliability in distinguishing those with LD from other voice disorders, largely due to the reliance on perceptual assessment methods and a wide range of clinical criteria without evidence to guide accurate diagnostic approaches. This is particularly true of VT, a voice disorder without clearly documented clinical features such that classification is not possible using current movement disorder consensus-based tremor syndrome criteria. Accurate differential diagnosis of LD from VT is essential to effective treatment planning and management as well as for accurate clinical and epidemiologic characterization and classification. The goal of this research is to systematically characterize individuals with LD and VT using currently available and novel clinical tools to determine distinguishing clinical features highly predictive of their correct diagnosis. Clinical phenotypic features will be compared between groups using acoustic, aerodynamic, laryngeal electromyography (EMG), and nasoendoscopy to quantify periodicity and task-specificity of voice patterns. Novel assessment tools and measures will also be used to study body distribution, condition of speech symptoms, and regularity or intermittency/phoneme-specificity of speech structure movement (kinematic) patterns using real-time magnetic resonance imaging and nasoendoscopy recordings during sustained phonation compared to voice- and voiceless-loaded sentences. Computational modeling will be used to assess aerodynamic, laryngeal EMG and speech structure kinematic patterns to simulate patient-specific acoustic output predictive of group membership as VT or LD. Outcomes of this research will significantly advance our clinical and scientific knowledge regarding optimal clinical tools and measures of LD and VT clinical features that result in a precise diagnosis of these neurological speech disorders.
132 studies on the registry are indexed under Dysphonia; 38 are open to participants now.
This study's planned enrollment of 165 is above the median of 123 across 40 observational studies indexed under Dysphonia.
Browse Dysphonia studies →Massachusetts Eye and Ear Infirmary is the lead sponsor of 100 studies on the registry; 23 are open to participants now.
Of its 13 completed or terminated interventional studies of FDA-regulated products, 7 (54%) have results posted.
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Patients with laryngeal dystonia Patients with voice tremor Healthy control individuals
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Patients with laryngeal dystonia (or spasmodic dysphonia)
Other: Clinical assessments of laryngeal function
Patients with voice tremor (essential or dystonic)
Other: Clinical assessments of laryngeal function
Healthy research volunteers
Other: Clinical assessments of laryngeal function
Participants will undergo acoustic, aerodynamic, respiratory kinematic, nasoendoscopic, and laryngeal EMG recordings, as well as real-time MRI of the upper airway for comprehensive characterization of shared and distinct features of laryngeal dystonia and voice tremor.
Differences in voice symptoms
Clinical phenotypic features and speech structure kinematics that distinguish between laryngeal dystonia and voice tremor
Time frame: 5 years
Plan to share: No
No publications or documents are linked to this record.
Started Nov 2022 (actual). Primary completion is estimated for Aug 2027, 57 months after the start.
Of 18 observational studies under Dysphonia, half reached primary completion within 26 months of starting (the median), counting those still running; a quarter within 12 and three quarters within 193. This study's planned 57 months is above that.
How these figures are worked out, and which studies are left out of them.
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