Trial Outcomes & Findings for Laryngeal Vibration for Spasmodic Dysphonia (NCT NCT03746509)
NCT ID: NCT03746509
Last Updated: 2025-05-04
Results Overview
Smoothed Cepstral Peak Prominence (CPPS) is an indicator of voice quality. It is measured in decibels. CPPS was measured from the voice signals of each participant during each study visit, and relative CPPS was calculated before and after vibration was applied on the laryngeal muscles of the participants. An increase in CPPS value indicates an improvement in voice symptoms.
Recruitment status
COMPLETED
Study phase
NA
Target enrollment
42 participants
Primary outcome timeframe
Testing performed in lab at Week 1
Results posted on
2025-05-04
Participant Flow
Participants were recruited from Fairview Voice Clinic at the University of Minnesota and through e-mail advertisements sent by the National Spasmodic Dysphonia Association as well as social media platforms. Recruitment began in the Fall of 2018.
Participant milestones
| Measure |
Low-High Treatment
Participants in the low-high treatment group will receive Laryngeal Vibration (Treatment) at 100Hz frequency once a week for a duration of 4 weeks (low intensity). Then they will switch and receive laryngeal vibration at 100Hz frequency every second day of the week (high intensity) for a duration of 4 weeks.
Laryngeal Vibration (Treatment): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
High-Low Treatment
Participants in the high-low treatment group will receive Laryngeal Vibration (Treatment) at 100Hz frequency every second day of the week for a duration of 4 weeks (high intensity). Then they will switch and receive laryngeal vibration at 100Hz frequency once a week for a duration of 4 weeks (low intensity).
Laryngeal Vibration (Treatment): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
Low-High Comparator
Participants in the low-high comparator group will receive Laryngeal Vibration (Comparator) at 5Hz frequency once a week for a duration of 4 weeks (low intensity). Then they will switch and receive laryngeal vibration at 5Hz frequency every second day of the week (high intensity) for a duration of 4 weeks.
Laryngeal Vibration (Comparator): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
High-Low Comparator
Participants in the high-low comparator group will receive Laryngeal Vibration (Comparator) at 5Hz frequency every second day of the week for a duration of 4 weeks (high intensity). Then they will switch and receive laryngeal vibration at 5Hz frequency once a week for a duration of 4 weeks (low intensity).
Laryngeal Vibration (Comparator): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
|---|---|---|---|---|
|
Overall Study
STARTED
|
11
|
10
|
11
|
10
|
|
Overall Study
COMPLETED
|
7
|
8
|
9
|
9
|
|
Overall Study
NOT COMPLETED
|
4
|
2
|
2
|
1
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Laryngeal Vibration for Spasmodic Dysphonia
Baseline characteristics by cohort
| Measure |
Low-High Treatment
n=11 Participants
Participants in the low-high treatment group will receive Laryngeal Vibration (Treatment) at 100Hz frequency once a week for a duration of 4 weeks (low intensity). Then they will switch and receive laryngeal vibration at 100Hz frequency every second day of the week (high intensity) for a duration of 4 weeks.
Laryngeal Vibration (Treatment): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
High-Low Treatment
n=10 Participants
Participants in the high-low treatment group will receive Laryngeal Vibration (Treatment) at 100Hz frequency every second day of the week for a duration of 4 weeks (high intensity). Then they will switch and receive laryngeal vibration at 100Hz frequency once a week for a duration of 4 weeks (low intensity).
Laryngeal Vibration (Treatment): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
Low-High Comparator
n=11 Participants
Participants in the low-high comparator group will receive Laryngeal Vibration (Comparator) at 5Hz frequency once a week for a duration of 4 weeks (low intensity). Then they will switch and receive laryngeal vibration at 5Hz frequency every second day of the week (high intensity) for a duration of 4 weeks.
Laryngeal Vibration (Comparator): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
High-Low Comparator
n=10 Participants
Participants in the high-low comparator group will receive Laryngeal Vibration (Comparator) at 5Hz frequency every second day of the week for a duration of 4 weeks (high intensity). Then they will switch and receive laryngeal vibration at 5Hz frequency once a week for a duration of 4 weeks (low intensity).
Laryngeal Vibration (Comparator): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
Total
n=42 Participants
Total of all reporting groups
|
|---|---|---|---|---|---|
|
Age, Categorical
<=18 years
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
|
Age, Categorical
Between 18 and 65 years
|
4 Participants
n=5 Participants
|
4 Participants
n=7 Participants
|
4 Participants
n=5 Participants
|
8 Participants
n=4 Participants
|
20 Participants
n=21 Participants
|
|
Age, Categorical
>=65 years
|
7 Participants
n=5 Participants
|
6 Participants
n=7 Participants
|
7 Participants
n=5 Participants
|
2 Participants
n=4 Participants
|
22 Participants
n=21 Participants
|
|
Sex: Female, Male
Female
|
7 Participants
n=5 Participants
|
5 Participants
n=7 Participants
|
7 Participants
n=5 Participants
|
4 Participants
n=4 Participants
|
23 Participants
n=21 Participants
|
|
Sex: Female, Male
Male
|
4 Participants
n=5 Participants
|
5 Participants
n=7 Participants
|
4 Participants
n=5 Participants
|
6 Participants
n=4 Participants
|
19 Participants
n=21 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
1 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
1 Participants
n=21 Participants
|
|
Race (NIH/OMB)
Asian
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
|
Race (NIH/OMB)
Black or African American
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
2 Participants
n=4 Participants
|
2 Participants
n=21 Participants
|
|
Race (NIH/OMB)
White
|
11 Participants
n=5 Participants
|
10 Participants
n=7 Participants
|
10 Participants
n=5 Participants
|
8 Participants
n=4 Participants
|
39 Participants
n=21 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=21 Participants
|
PRIMARY outcome
Timeframe: Testing performed in lab at Week 1Smoothed Cepstral Peak Prominence (CPPS) is an indicator of voice quality. It is measured in decibels. CPPS was measured from the voice signals of each participant during each study visit, and relative CPPS was calculated before and after vibration was applied on the laryngeal muscles of the participants. An increase in CPPS value indicates an improvement in voice symptoms.
Outcome measures
| Measure |
Low-High Treatment
n=10 Participants
Participants in the low-high treatment group will receive Laryngeal Vibration (Treatment) at 100Hz frequency once a week for a duration of 4 weeks (low intensity). Then they will switch and receive laryngeal vibration at 100Hz frequency every second day of the week (high intensity) for a duration of 4 weeks.
Laryngeal Vibration (Treatment): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
High-Low Treatment
n=10 Participants
Participants in the high-low treatment group will receive Laryngeal Vibration (Treatment) at 100Hz frequency every second day of the week for a duration of 4 weeks (high intensity). Then they will switch and receive laryngeal vibration at 100Hz frequency once a week for a duration of 4 weeks (low intensity).
Laryngeal Vibration (Treatment): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
Low-High Comparator
n=10 Participants
Participants in the low-high comparator group will receive Laryngeal Vibration (Comparator) at 5Hz frequency once a week for a duration of 4 weeks (low intensity). Then they will switch and receive laryngeal vibration at 5Hz frequency every second day of the week (high intensity) for a duration of 4 weeks.
Laryngeal Vibration (Comparator): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
High-Low Comparator
n=9 Participants
Participants in the high-low comparator group will receive Laryngeal Vibration (Comparator) at 5Hz frequency every second day of the week for a duration of 4 weeks (high intensity). Then they will switch and receive laryngeal vibration at 5Hz frequency once a week for a duration of 4 weeks (low intensity).
Laryngeal Vibration (Comparator): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
|---|---|---|---|---|
|
Voice Assessment During First Visit
|
0.045 decibel
Interval -0.79 to 1.28
|
0.17 decibel
Interval -0.91 to 1.05
|
0.13 decibel
Interval 0.01 to 1.14
|
-0.47 decibel
Interval -0.64 to 0.56
|
PRIMARY outcome
Timeframe: Testing performed in lab at week 11Smoothed Cepstral Peak Prominence (CPPS) which is an indicator of voice quality was measured in participants. CPPS was measured in participants during the first visit, and relative CPPS was calculated before and after vibration was applied on the laryngeal muscles of the participants.
Outcome measures
| Measure |
Low-High Treatment
n=8 Participants
Participants in the low-high treatment group will receive Laryngeal Vibration (Treatment) at 100Hz frequency once a week for a duration of 4 weeks (low intensity). Then they will switch and receive laryngeal vibration at 100Hz frequency every second day of the week (high intensity) for a duration of 4 weeks.
Laryngeal Vibration (Treatment): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
High-Low Treatment
n=10 Participants
Participants in the high-low treatment group will receive Laryngeal Vibration (Treatment) at 100Hz frequency every second day of the week for a duration of 4 weeks (high intensity). Then they will switch and receive laryngeal vibration at 100Hz frequency once a week for a duration of 4 weeks (low intensity).
Laryngeal Vibration (Treatment): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
Low-High Comparator
n=7 Participants
Participants in the low-high comparator group will receive Laryngeal Vibration (Comparator) at 5Hz frequency once a week for a duration of 4 weeks (low intensity). Then they will switch and receive laryngeal vibration at 5Hz frequency every second day of the week (high intensity) for a duration of 4 weeks.
Laryngeal Vibration (Comparator): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
High-Low Comparator
n=8 Participants
Participants in the high-low comparator group will receive Laryngeal Vibration (Comparator) at 5Hz frequency every second day of the week for a duration of 4 weeks (high intensity). Then they will switch and receive laryngeal vibration at 5Hz frequency once a week for a duration of 4 weeks (low intensity).
Laryngeal Vibration (Comparator): The strength of the vibration is similar to the vibration experienced from vibrating cell phones or gaming joysticks. Vibro-tactile stimulation at the applied frequency and amplitude is not known to cause pain or tissue damage. The participant may feel a mild tingling or vibrating sensation. Preliminary testing on healthy human subjects showed that at the given vibration parameters no adverse reactions occur.
|
|---|---|---|---|---|
|
Final Voice Assessment
|
0.96 decibel
Interval 0.71 to 1.3
|
0.55 decibel
Interval -0.82 to 0.63
|
0.64 decibel
Interval 0.21 to 1.37
|
0.23 decibel
Interval -0.01 to 0.38
|
SECONDARY outcome
Timeframe: Testing performed in lab at Week 1Cortical activity before, during, and after the vibration will be recorded via a a 64-channel EEG system at a sampling frequency of 512 Hz.
Outcome measures
Outcome data not reported
SECONDARY outcome
Timeframe: Testing performed in lab at Week 11Cortical activity before, during, and after the vibration will be recorded via a a 64-channel EEG system at a sampling frequency of 512 Hz.
Outcome measures
Outcome data not reported
Adverse Events
Low-High Treatment
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
High-Low Treatment
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Low-High Comparator
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
High-Low Comparator
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place