News Archive

Dystonia Awareness Week: June 6-12

Dystonia Awareness Week occurs from June 6-12, 2010. Dystonia is the third most common movement disorders after Parkinson's Disease and Tremor, affecting more than 300,000 people in North America. Dystonia is a neurological movement disorder that causes muscles in the body to pull or spasm. More...

Spasmodic dysphonia, otherwise known as laryngeal dystonia, is a focal dystonia involving the muscles that control the vocal cords. Spasmodic dysphonia makes speaking difficult because the voice has either a strained, hoarse, whispered quality or a low breathy quality.

Please take the opportunity of this weeklong event for Dystonia Awareness Week to help raise awareness about dystonia. Your help in awareness raising can be as simple as handing out an NSDA trifold wallet card or directing people to the NSDA website at:

The NSDA is part of the Dystonia Advocacy Network (DAN). The DAN brings together various dystonia organizations in order to advocate on issues of common concern to those affected by dystonia.

Message from NSDA's New President - Charlie Reavis

It has been a rewarding experience serving the National Spasmodic Dysphonia Association as a member of its Board of Directors for several years, and it is my great pleasure to now serve as President of the Board. Our past President David Barton has served the NSDA in this position since 2005 with dedication, commitment to the NSDA mission and excellent leadership. On behalf of the NSDA Board and the spasmodic dysphonia community, I thank David for his outstanding service and significant accomplishments. More...

My voice problems became severe in early 2000 and I was fortunate to find an otolaryngologist and speech-language pathologist in 2001 who diagnosed my voice condition as adductor spasmodic dysphonia. They played the NSDA video and I immediately knew that was what I had and that there were others with the same voice condition.

As I am sure all of you felt, I was relieved to have a diagnosis but disappointed to also learn that the cause was unknown and the treatments only temporary. I explored the NSDA website in an attempt to learn more about SD but soon discovered that the knowledge was limited and very little research had been conducted since this was a rare condition with a very small patient population. This only fueled my desire to find a way to do something, so when then President Dot Sowerby contacted me and asked if I would join the NSDA Board, I accepted.

I have been actively engaged with the Board and working closely with David and the other Board members to grow the organization and provide more support and services to the SD community. We have made significant strides in serving our mission of increasing awareness of SD, educating the public and medical community about SD, providing support for SD patients and their families and pushing research to find the cause of SD that will eventually lead to a cure for our voice condition. I am extremely optimistic about the future of NSDA and our plans to enhance the support and services to the entire SD community and continue to drive SD-specific research.

During our recent Board meeting and Leadership Day in Denver, I shared my vision for NSDA:

"Ensure the ongoing viability of the Organization that will continue to lead the effort to eradicate Spasmodic Dysphonia."

One thing I have learned and admire about people with SD is their perseverance, dedication and a wonderful stubbornness that anything is possible. I am convinced that working together with one loud and clear NSDA voice that my vision for NSDA can become a reality. I look forward to working hard on your behalf and with your help and support to accomplish our mission and strive to achieve our vision. With your help and support we can accomplish our mission and strive to achieve our vision. I look forward to working hard on your behalf.

Thank you for your continued commitment and support!

Charlie Reavis
NSDA President

The Congressionally Directed Medical Research Program Adds Dystonia to the List


We have seen many opportunities to advance research in the field of spasmodic dysphonia with the funding of the first NSDA independent grant and the establishment of the Dystonia Coalition. Now, we add another funding mechanism for dystonia/spasmodic dysphonia research!

The National Spasmodic Dysphonia Association, a proud member of the Dystonia Advocacy Coalition (DAC), is pleased to announce the inclusion of dystonia on the list of diseases eligible for funding through the Congressionally Directed Medical Research Program (CDMRP). This achievement, reached after several years of tireless, collaborative efforts by the advocates of the DAC, now allows for members of the dystonia research community to apply for funds in support of their work. In particular, we would like to thank Jim Anderson from St. Pete's, Florida, for his efforts in working on this issue and assembling a team of people to ensure dystonia, and specifically, spasmodic dysphonia, would be included in this funding.

The Congressional Directed Medical Research Program is funded through the Department of Defense via annual Congressional legislation known as the Department Appropriations Act (the support is in response to requests by consumer advocates and disease survivors). CDMRP will issue a program announcement for 2010 funding opportunities, including dystonia.

NSDA joins with the other DAC member organizations, the Benign Essential Blepharospasm Research Foundation, DySTonia, Inc., the Dystonia Medical Research Foundation, and the National Spasmodic Torticollis Association, to advocate for all persons affected by dystonia and supports a legislative and policy agenda that meets the needs of the dystonia community.

Organizational members of the DAC will now work to promote this program to the dystonia research community to help advance dystonia research.

NIH Funds $6.2 Million Dollar Grant for Focal Dystonias


Officials at the National Institutes of Health (NIH) have announced the funding of a five year clinical research grant award aimed at forming a multicenter Dystonia Coalition to advance clinical research on primary focal dystonias, including cervical dystonia, spasmodic dysphonia, blepharospasm, and others. Leading the Coalition will be H. A. Jinnah, M.D., Ph.D., Professor of Neurology and Human Genetics at Emory University in Atlanta, GA.

The $6.2 million award will allow the Dystonia Coalition to cultivate a better understanding of the primary focal dystonias and find better therapies. This includes projects to develop a better understanding of their natural history, establish instruments appropriate for monitoring disease severity in clinical trials, and develop proper diagnostic criteria. The creation of a biorepository to store biological samples to support future research is also planned, making these resources available to investigators worldwide. The Coalition will bring together the most committed dystonia researchers in North America and Europe, along with dystonia patient advocacy groups.
“Dystonias are rare and devastating diseases, with limited and sometimes inadequate treatment options,” explains Dr. Jinnah. “Funding of the Dystonia Coalition will allow us to address unmet needs in focal dystonia research, as well as make resources available to other investigators that will help to advance the field.”

One component of this grant is aimed at developing an accurate diagnostic test for identifying patients with spasmodic dysphonia who do not have other voice disorders. This was identified as the highest priority need when a research planning conference was held at the NIH in June 2005. The report of that meeting provided the impetus for this project and contained a pilot study of a proposed diagnostic test.

The study will take place over five years and has three parts. In the first, the diagnostic test will be evaluated at four voice centers (Washington University at St Louis; Medical College of Wisconsin in Milwaukee; New York Center for Voice and Swallowing Disorders associated with Columbia University, and Emory University in Atlanta) to determine whether otolaryngologists, speech pathologists and neurologists at each center can use it accurately and reliably for determining which patients have spasmodic dysphonia and which patients have other voice disorders such as psychogenic dysphonia, muscular tension dysphonia or vocal fold paresis.
In the second phase it will be determined if medical professionals not specializing in voice can also use it to accurately and reliably diagnose spasmodic dysphonia. In the final phase, a double blind treatment study will determine if this new test can accurately quantify changes in severity of the disorder for conducting clinical trials in spasmodic dysphonia. If successful this study will provide a new instrument to serve as a basis for increasing research on spasmodic dysphonia, as we will then be able to identify persons with spasmodic dysphonia and determine the severity of their voice disorder.

“This funding will allow us to develop the first test for accurately identifying who has spasmodic dysphonia and will allow us to measure treatment effects. This will provide the base from which to increase research attention to further understanding and improved treatment for spasmodic dysphonia,” says Christy Ludlow, Ph.D., Scientific Director of the National Spasmodic Dysphonia Association. The NSDA is proud to be part of the research coalition and hopes it will bring a greater interest to this field of research.

The NSDA is dedicated to advancing medical research into the causes of and treatments for spasmodic dysphonia, promoting physician and public awareness of the disorder, and providing support to those affected by spasmodic dysphonia through symposiums, support groups, and on-line resources. The NSDA is comprised of people with SD, healthcare professionals, volunteers, friends, and families. It is the only organization dedicated solely to the SD community. Together, we continue to pursue our mission through awareness, advocacy, and outreach; help to improve the lives of people dealing with SD; and to work to support and encourage research in order to bring a greater understanding to this disorder.

Patient Advocacy Groups that are members of the Dystonia Coalition include:

• American Dystonia Society
• Bachmann-Strauss Dystonia & Parkinson Foundation
• Beat Dystonia
• Benign Essential Blepharospasm Research Foundation
• DySTonia, Inc.
• Dystonia Medical Research Foundation
• National Spasmodic Dysphonia Association
• National Spasmodic Torticollis Association
• Tyler's Hope for a Dystonia Cure
• We Move

Spasmodic Dysphonia and Quality of Life Research Study Results


By Thomas B. Hofmann PhD, LCSW, CAPP

Some of you participated in the “Spasmodic Dysphonia and Quality of Life” survey in 2008. In that study, several types of spasmodic dysphonia were eventually compared in order to see if there was a difference in a person’s perceived quality of life after botulinum toxin treatment. At first, it was suspected that people with Abductor SD would score lower on a quality of life survey than those with Adductor SD. In previous studies, Adductor SD was more effectively treated with botulinum toxin than Abductor SD, though both types did show improvement after this treatment according to expert voice rating.

In this study, there was no statistically significant difference in the quality of life scores between the two types. In an effort to explain the result further, it was found that age of the participants and the amount of time that they had been dealing with SD had a small effect on quality of life scores, but not enough to explain the result. The severity of the SD, the presence of significant side effects of SD, and gender, did not appear to influence the result to any statistical significance.

However, the combined types, including mixed SD (Abductor and Adductor), or any type with an accompanying tremor receiving botulinum toxin treatment, did have a significantly lower quality of life score than those with only Abductor or Adductor SD alone. This result is also worth repeating as it may have implications for botulinum toxin treatment, or other adjunct therapies.
On a separate note, while reviewing the body of previous SD studies, this writer came across a study by de Jong, Cornelius, Wuyts, Kooijman, Shutte, Oudes and others in 2003. They studied 76 teachers with a voice disorder, and found that it was important to know where the person was in their grieving process of accepting the voice disorder in order to assess personal adjustment and appropriateness of coping strategies to the voice disorder.

The researchers used a model of grief with three stages. In stage 1, the voice disorder is experienced as a “Threat”, and is usually accompanied by a desperate search for help, isolation, depression, anxiety and exhaustion. Stage 2 is called “Falling into the pit”, in which the person starts to lose the emotional urgency to resolving their voice disorder, and comes to more emotional acceptance and less desperation about it. Finally, those who make it to stage 3 find “Renewal”, in which a person finds maximum recovery in physical, functional, psychological and social domains. This can include contributing positively to helping others who struggle with the same condition, or actually any human condition.

Sherbourne, Meredith, Rogers and Ware found in 1992 that social support provided to persons with a chronic illness actually helped them maintain their physical health. Combining the finding from the de Jong et al. study with the Sherbourne et al. study, members of the NSDA are to be congratulated for effectively being in the process of working out their own struggle with SD so that others can be helped to improve their own quality of life as well. Additionally, the whole idea of what a person’s adjustment stage to SD is also deserves further study.

Botulinum Toxin Update


The Food and Drug Administration (FDA) recently took measures to ensure that botulinum toxin products are used safely and appropriately. A mandatory black box warning label will be required for all botulinum toxin products sold in the United States. This will be applicable to currently approved formulations as well as new ones when they come to market in the future.

This is the most serious type of warning for prescription drug labeling, and it was added because of reports of serious muscle weakness along with speech, swallowing, and vision impairments in children with cerebral palsy. These children were being treated for spasticity with large doses of the product. While it was used off-label, similar effects have been reported in adults treated for both approved and unapproved uses.

In addition, all manufacturers of botulinum toxin products must implement a Risk Evaluation Management Strategy (REM) to ensure that physicians use the products knowledgably and patients must be informed of potential risks and provided with new information about the products. These actions are also taken to ensure that physicians know that botulinum toxin products available are measured in different units and therefore cannot be used interchangeably.

Currently, there are three botulinum toxin products approved for the treatment of various forms of dystonia. This includes Botox� manufacturedby Allegan (botulinum toxin type A), Myobloc� manufactured by Solstice (botulinum toxin type B), and most recently Dysport�, manufactured by Medicis Pharmaceutical Corp and Ipsen.

Dysport� has been recently approved for the treatment of cervical dystonia as well as an anti-wrinkle treatment. It is expected to launch for cervical dystonia during the second half of 2009. It has been used for both medical and cosmetic purposes in Europe and other parts of the world for over 10 years.

Another type A botulinum toxin, Xeomin�, manufactured by Merz Pharmaceuticals, is currently being reviewed by the FDA for the treatment of blepharospasm and cervical dystonia.

The NSDA recommends discussing any safety concerns you may have with a healthcare professional who is trained and experienced with injecting with botulinum toxin for spasmodic dysphonia.

NSDA Funds Research Grant


The NSDA announces its first independently-funded research grant. The proposed research will be conducted by a neurologist, Dr. Christian Kell, and is entitled, “Parametric analyses of pathology and treatment effect in spasmodic dysphonia.” The study will involve both structural and functional brain imaging in persons with spasmodic dysphonia before and after treatment with botulinum toxin injection. The purpose of this brain imaging research is to determine what parts of the brain are altered both structurally and functionally and may account for voice abnormalities in persons with spasmodic dysphonia. Because treatment with botulinum toxin is only effective for a short period and the symptoms reappear after the effects of the toxin wear off, the authors plan to identify brain regions that are abnormal in persons with spasmodic dysphonia regardless of symptoms or treatment with botulinum toxin. It is hoped that the authors will identify the brain abnormalities responsible for producing symptoms such as voice breaks in spasmodic dysphonia. Once this region is known, future research can be aimed at changing this brain abnormality for long term treatment of this disorder.

In previous research, two studies found that functional differences occurred in brain activity in persons with spasmodic dysphonia (SD). One was a study conducted at the National Institute of Health by Ali et al., and published in the Journal of Speech-Language Hearing Research in 2006. The authors used Positron Emission Tomography (or PET) to measure activity in the brain and found that when persons with SD either whispered or did not have voice symptoms they had reduced brain activity in the region that receives sensory feedback from the larynx. Once the patients were treated with botulinum toxin injections this abnormality disappeared, suggesting it might have been the result of symptoms rather than causing the symptoms. However, another brain abnormality was present in persons with SD both when they had symptoms and when they did not—reduced activity in the supplementary motor area (SMA). This area was identified as being involved in speech production many years ago by Dr. Wilder Penfield and colleagues in the 1940s and 1950s. Abnormalities in the SMA were present in the persons with SD even when they whispered, suggesting that this abnormality was always there. Another study by Haslinger et al., 2005 was conducted in Munich, Germany and published in the journal Neurology. These authors found reduced brain activation in the primary sensorimotor areas which was not altered by treatment. Only one study thus far has examined structural differences in the brains of persons with SD; this was conducted at the National Institutes of Health by Simonyan et al., and published in the journal Brain. These authors used high resolution structural imaging with a special technique, diffusion tensor imaging, and found reductions in the white matter tracts on the right side of the brain which were confirmed in a post-mortem study of one brain from an SD patient.

The research to be supported by the NSDA and conducted by Kell et al., in Frankfurt, Germany, will be the first combined use of both functional and structural techniques in the study of the brain in persons with SD using high resolution imaging. This will involve a collaboration across two centers between Dr. Kell, a neurologist and Dr. Katrin Neuman, an otolaryngologist, both at Goethe University in Frankfurt, and Dr. de Jonckere, a speech language pathologist at the University of Utrecht in The Netherlands. Two years of support will be provided and this study should build on research that has already been done. It provides a unique opportunity to learn which of the brain functional and structural abnormalities found by other scientists are always present in SD and should be focused on developing long-lasting treatments for persons with spasmodic dysphonia.

Brainstem Pathology in Spasmodic Dysphonia


Kristina Simonyan, M.D., Ph.D., Christy L. Ludlow, Ph.D., Alexander O. Vortmeyer, M.D.
Published in Laryngoscope (2009): Sept 30

Abstract: Spasmodic dysphonia (SD) is a primary focal dystonia of unknown pathophysiology, characterized by involuntary spasms in the laryngeal muscles during speech production. We examined two rare cases of postmortem brainstem tissue from SD patients compared to four controls. In the SD patients, small clusters of inflammation were found in the reticular formation surrounding solitary tract, spinal trigeminal, and ambigual nuclei, inferior olive, and pyramids. Mild neuronal degeneration and depigmentation were observed in the substantia nigra and locus coeruleus. No abnormal protein accumulations and no demyelination or axonal degeneration were found. These neuropathological findings may provide insights into the pathophysiology of SD.

Lay summary: Patients with spasmodic dysphonia (SD) have a neurological condition, which results in voice breaks during speech production. The cause of the neurological condition is unknown. This study of brain tissue was possible thanks to the generous donations of their brains after their death by two of our former patients with adductor SD. We examined the lower part of the brain, called the brainstem, in these two patients and compared the results to the brainstems of four persons who did not have SD or other neurological conditions. We found that the brains of patients with SD had small accumulations of inflammatory cells in the regions of the brainstem that control laryngeal behaviors. We also found a mild loss of neurons in the region called the substantia nigra, which is important for movement control. These findings show that some abnormal processes were ongoing in the brainstem of these two SD patients that may have affected their voice production. This study is just another small but important step in understanding SD; more research is needed before findings such as these will be able to identify the cause of SD.

Research Priorities in Spasmodic Dysphonia


Summary Prepared by Christy Ludlow, Ph.D., NSDA Scientific Board Chairperson

This article reviews the results of a workshop held at the National Institutes of Health in June 2005 to identify research priorities for understanding and treating Spasmodic Dysphonia. The workshop was sponsored by the NIH Office of Rare Diseases, the National Institute on Deafness and Other Communication Disorders, the National Institute of Neurological Diseases and Stroke, the Movement Disorder Society, and the National Spasmodic Dysphonia Association. Fourteen specialists in otolaryngology, neurology, and neuroscience were invited to participate.

This summary is divided into four sections; each section presents a synopsis of workshop presentations followed by recommendations for research. The first section describes Spasmodic Dysphonia (SD) and lists recommendations for diagnosis. The second section summarizes what is known about the patient population and the types of studies that could help define the population better. In the third section, research and research recommendations to discover the causes and mechanisms in SD are discussed and in the fourth section, future research needs on treatment options are discussed.

The original article was published in Otolaryngology-Head and Neck Surgery, 2008 Oct;139(4):495-505

Article authors: Christy Ludlow, Charles Adler, Gerald Berke, Steve Bielamowicz, Andrew Blitzer, Susan Bressman, Mark Hallett, H.A. Jinnah, Uwe Juergens, Sandra Martin, Joel Perlmutter, Christine Sapienza, Andrew Singleton, Charlotte Tanner, Gayle Woodson

What is Spasmodic Dysphonia?
Spasmodic dysphonia (SD) is a rare voice disorder that develops spontaneously in mid-life. Patients with SD have a hard time speaking; their speech is strained or choked, and patients all report that it requires a huge amount of effort to speak. After the initial onset, the disorder gradually progresses then remains chronic for life. More women than men are affected; between 60-80% are female.

No diagnostic marker is available for SD; currently the speech symptoms are used and are difficult to differentiate from other voice disorders such as hyperfunctional voice or muscular tension dysphonia.
The strained, effortful, intermittent voice that is characteristic of SD is due to involuntary spasms in the muscles of the larynx during speech. The spasms are intermittent and are task-specific, occurring only during speech. Adductor SD involves spasmodic hyperadduction of the vocal folds producing involuntary closing of the vocal folds, leading to voice breaks during vowels.

In the less common form, abductor SD, involuntary opening of the vocal folds results in the prolongation of voiceless consonants (e.g. s, f, p, t, k, h) as breathy breaks. Rarely, both adductor and abductor spasms are present. Treatment outcome frequently serves as an important means to confirm the initial diagnosis; patients with hyperfunctional voice frequently resolve with voice therapy while patients with SD rarely benefit from voice therapy but are benefited by botulinum toxin injection. Tremor and SD can occur together in the same patient, but hyperfunctional voice and tremor are rarely seen together. Despite the known differences, it remains difficult to differentiate SD from hyperfunctional voice and other voice disorders. The following recommendations for the diagnosis of spasmodic dysphonia should serve as a first step in enhancing research on this disorder.

Recommendations for Diagnosis
The highest priority identified by the workshop is the need for a common diagnostic procedure. The workshop recommended a 3-step process, the first step being a simple screening questionnaire which allows patients to identify themselves as possibly having SD, the second step being a clinical examination that identifies individuals with probable SD, and the third step requires a nasolaryngoscopy examination to confirm a definitive diagnosis of SD. A preliminary study demonstrated that these procedures have good potential for differential diagnosis and it was recommended that a multidisciplinary Spasmodic Dysphonia Study Group be established and charged with designing a validation study to determine the accuracy and reliability of the proposed diagnostic procedure.

Who gets Spasmodic Dysphonia?
Spasmodic dysphonia is a rare disorder. It is also clinically heterogenous and requires experts to recognize and identify the disorder. These factors have made it difficult to get answers to basic questions regarding prevalence, incidence, age of onset, gender and ethnic representation, regional variation, and risk factors.

The estimated prevalence of SD is 1 case per 100,000 population. About 30% of patients with SD also have vocal tremor. No controlled studies of risk factors have been conducted; a small case series suggests an association of SD with autoimmune disease, thyroid disorders, or antihistamine use. Approximately 30% report a prior upper respiratory tract infection or suffering a major life stress (21%) at the time of onset.

Although fourteen genes have recently been associated with dystonic disorders, none have been associated with SD. Genetic studies of SD have not been done, because large families with only SD have not been described.

New technology is becoming available that will allow for the identification of genes from cohorts of unrelated patients and will make it possible to search for genetic association in a disease cohort compared to a control cohort. While powerful, this method requires a large number of patients with a standard clinical presentation as well as considerable sums of money.
The impetus for finding a gene is that it then becomes possible to develop both animal and cellular models of the disease, to study the biochemical cascade of events, to develop hypotheses and then to try and intervene in the physiologically relevant pathways to halt the development of the disorder.

Recommendations for Population Research
Several of the following recommendations for population research were identified as a lower priority given the difficulties with accurate diagnosis. Implementation of these recommendations awaits the development of accurate diagnostic procedures.

1. Brain Banks
Several brain banks already exist and the SD community may be able to collaborate with existing banks. Annual exams need to be given to the living donors to rule out additional neurological diseases/disorders. The SD Study Group was charged with identifying and organizing sites for an SD Brain Bank.
2. Genetic Research
Going after a gene for SD was described as a million dollar experiment with no guarantees, and at this time is considered premature. Once diagnostic criteria are standardized, evidence is needed regarding the assumption that a common etiology exists between SD and other focal dystonias. The first steps would be to standardize clinical criteria, to collect family histories, and to deposit a blood sample in a central public repository.

3. Patient Registry
The pitfalls of a patient registry were discussed; principal among them was the fact that a voluntary registry would not contain accurately diagnosed cases. A registry may be a useful way to identify patients who would be willing to participate in clinical trials (in which case the questions must be approved by an IRB and must adhere to HIPAA guidelines).

What are the Neurological Abnormalities in Spasmodic Dysphonia?
The mammalian vocalization system consists of a primitive, innate, preprogrammed system which produces laughing, crying, and other involuntary sounds, as well as a second, more recently evolved, system for the control of learned vocalizations in humans. All subhuman mammalian species possess the innate system, while only humans have developed the system for learned vocalizations. This means that animal models for SD will not mimic the phenomenology of SD which affects voice production only during speech and not during laughing, crying, and
other involuntary sounds.

Studies in other dystonias suggest there may be a deficiency in the caudate/putamen. Others suggest involvement of the dopaminergic pathways in dystonia, although the specific pathway and the type of defect still remain to be identified. Loss of inhibition is well documented in dystonia. Treatments for dystonia may increase inhibition, or replace inhibition that is missing. Increased neuroplasticity has been demonstrated in patients with writer’s cramp, the form of focal dystonia most similar to SD. In patients with SD, increased neuroplasticity could set the stage for a disease response to repetitive activity, injury or increased use. Because the sensory system is a
prime driver of the motor system, disordered sensory input might lead
to disordered motor output.

In the laryngeal muscles, where the symptoms of SD are manifested, the emerging picture is one of disordered inhibition. The larynx is extremely sensitive to any stimulation of the mucosa. Receptors are present for not only tactile stimulation but also to negative pressure, air flow and cold, a lack of chloride ions, and muscle activity. Studies suggest sensorimotor disorders may be present in SD such
as reduced inhibition of motor responses to sensory feedback.

Recommendations for Basic Research
1. Animal Models
An animal model may or may not mimic the clinical state of SD because no other mammals or primates exhibit learned vocalizations similar to humans. However, if the underlying brain disorder can be modeled, the model may be useful despite differences in laryngeal behavior across species.

Several animal models of generalized dystonias (mostly in rodents) are available; one involves striatal dopamine depletion and slight muscle weakening. Such a strategy may be applicable to the development of a model for SD. Songbirds might be considered as a model for SD. Vocalization by songbirds share some similarities to human speech having both innate and learned sounds, although there are differences in the peripheral and central nervous systems involved in human speech and birdsong. If a suitable model were identified, experimental manipulations that could predict a cause or new treatments for SD could be performed.

2. Basic Brain Circuitry
Fully understanding the anatomy and circuitry in the larynx and the brain provides the foundation for further research. The anatomy of laryngeal reflexes, the specific connections between sensory relay stations, the motor inputs to the nucleus ambiguus, and descending connections from cortex to brainstem nuclei, all require further research. This research would have to be done in animals, and the choice of animal was debated (rodents vs primates). As the circuitry is defined, higher brain centers that control and modulate laryngeal output need to be identified as well as drugs to modify these centers. The brain centers identified in animal studies could be compared to areas in human SD brains that appear abnormal from neuroimaging studies. In addition, neuropathological data from post-mortem studies of SD brains should also be compared to the emerging animal data.

3. Related Experiments
a. Some evidence exists that an autoimmune event may be associated with development of SD. A study that could establish whether a link does/does not exist would be worthwhile.

b. Some patients with SD have had 70 injections of botulinum toxin into their larynx. The cumulative effects on the muscle are not known. Animal studies that reproduce multiple injections should help to understand the long term effects of botulinum toxin injection on muscle physiology.

Developing Effective Treatments for SD
The most common treatment for SD is botulinum toxin injections into laryngeal muscles. Both botulinum neurotoxin type A and type B work by blocking release of acetylcholine at the neuromuscular junction, and consequently reducing motor activity. About 90% of patients with adductor SD improve after receiving an injection, for 3-12 months.

Patients with abductor SD also respond to botulinum toxin injections, although it is not as effective and a slightly higher risk is involved, since t he muscles injected are also required for respiration. The disadvantage of botulinum toxin injection is that it must be repeated every 3-6 months. The dose response range is very wide; some patients require up to 80 times what other patients need to receive the same benefit. In addition, long term results and safety have been challenges that still need to
be addressed.

When surgical approaches to treatment of SD are considered, the possibilities include laryngoplasties, myomectomies, and denervation/reinnervation. Laryngoplasty involves changing the cartilagenous skeleton of the larynx, either through anterior commissure pushback, thyroid cartilage widening, or medialization of the vocal chords. Patients who have these procedures usually do not experience lasting benefit. Myomectomies cut the muscles of the larynx, and the thyroarytenoid, lateral cricoarytenoid, and posterior cricoarytenoid muscles have all been cut. These procedures can be performed through a thyroid cartilage window or by endoscopic means.

Dysfluency can be improved, although vocal harshness may result and lasting benefit has been unpredictable. The denervation/reinnervation procedure is currently being used in patients with pure adductor SD; patients with significant tremor or mixed dystonia are not candidates. The procedure is performed bilaterally. Women benefit more than men. Questionnaires returned by two-thirds of patients report some benefit. A small number went back to botulinum toxin injections, which are still possible after this type of surgery. Some patients reported having mild swallowing difficulties.

Recommendations for Treatment Research
Researchers need to be wary because placebo effects tend to be quite large in this patient group. It is important to have controlled studies and check for previous treatments and concomitant signs and symptoms. An adequate follow-up duration of 3-5 years is important, particularly as SD is a chronic condition.

Outcome measures should include subjective scales, objective tests, and quality of life questionnaires. Blinded videotape review is recommended where videotapes from before and after treatment are scrambled and rated by an uninvolved investigator. Small, open-label trials would be a good way to start discovering new treatment options. Since so little has been done, small trials would be a better use of resources than to commit to a big, randomized, placebo-controlled trial.

1. Confirm Physiology
Further imaging studies should be performed to confirm that the pathophysiology found in other dystonias is applicable to SD. Such studies could also potentially help to define SD, and place spasmodic dysphonia in context with other dystonias.

2. Pharmacological Treatments
Only the tremor component in SD modestly responds to oral medications such as beta blockers, although the SD tremor does not. Some patients receive both botulinum toxin injections and a low dose of an oral neuroactive drug which may be effective in combinations while the drug alone may not have much effect. These reports are anecdotal and prone to placebo effects. The recommendation is to systematically test combinations of botulinum toxin injections with a low dose of oral medications, testing known anticonvulsants, antidepressants, benzodiazepines, or dopamine agonists. Immunosuppressive agents might also be worth trying, especially in patients with incipient SD.

3. Surgical Procedures
Information should be collected on all patients who are receiving surgery for SD. The type of procedure should be documented with a standardized preoperative history and baseline and postoperative testing. Videotapes should be rated by blinded independent reviewers. Even an attempt to collect retrospective information from patients who have already received surgery is worthwhile, as well as collecting information on prospective patients. This approach, while not a clinical trial, might be valuable to catalog and disseminate information on surgical outcomes. A trial to evaluate the efficacy of various surgical procedures is greatly needed. Surgeons at multiple centers would need to be involved and trained to perform the procedure. Thorough long term follow-up at multiple centers would be most convenient to patients and increase long term information. Animal studies are needed to understand the long term effects of surgery on laryngeal physiology.

4. Deep Brain Stimulation
Deep brain stimulation has proven to be effective in other conditions, such as Parkinson’s. However, given the limited benefits seen for speech and voice in these other conditions, caution should be used regarding deep brain stimulation for patients with SD.

Participate in the 2010 Dystonia Advocacy Day


The National Spasmodic Dysphonia
Association is a proud partner of the Dystonia Advocacy Coalition (DAC). The mission of the DAC is to speak with one voice for issues affecting the dystonia community. We invite you to participate in Dystonia Advocacy Day in Washington, D.C. on May 4-5, 2010. The goal of this day is to inform legislators about dystonia and how it has affected our lives.

This important annual event brings together dystonia affected individuals and families from all dystonia patient organizations from across the country for legislative activities which include:

• Comprehensive advocacy training on Tuesday, May 4
• Networking Dinner for all advocates
• A full day of meetings with your Members of Congress on Wednesday, May 5
• The opportunity to make a difference.

We understand that some persons might feel intimidated or reluctant to speak to their representatives for the first time. The training session on Tuesday will address all of your concerns. Training topics include: How to make a Hill visit, the current climate on the Hill and role playing. You will be assigned to teams for Advocacy Day and a mentor will be assisting each team. Visits will be arranged in advance, and you will be given a map of your assignments, directions, and leave behind materials for each of the offices you visit.

By working together we will strengthen our voice and advance our issues. We will be heard!

All volunteers who have participated in these events in the past have found them to be an incredibly rewarding and empowering experience and were proud to have exercised their right to communicate with elected officials. To register for Advocacy Day or receive more information please e-mail and put Advocacy Day in the subject line or call the NSDA at 1-800-795-6732.

In addition, if you are interested in making visits locally to your representatives, the NSDA has a booklet that can offer helpful suggestions. Help us speak out for spasmodic dysphonia!