Spasmodic dysphonia#Adductor spasmodic dysphonia

Symptoms of spasmodic dysphonia can come on suddenly or gradually appear over the span of years. They can come and go for hours or even weeks at a time, or remain consistent. Gradual onset can begin with the manifestation of a hoarse voice quality, which may later transform into a voice quality described as strained with breaks in phonation.Colton, R. H., & Casper, J. K. (2006). Understanding voice problems: A physiological perspective for diagnosis and treatment. Baltimore, MD: Lippincott Williams & Wilkins. These phonation breaks have been compared to stuttering in the past, but there is a lack of research in support of spasmodic dysphonia being classified as a fluency disorder.{{cite journal | vauthors = Cannito MP, Burch AR, Watts C, Rappold PW, Hood SB, Sherrard K | title = Disfluency in spasmodic dysphonia: a multivariate analysis | journal = Journal of Speech, Language, and Hearing Research | volume = 40 | issue = 3 | pages = 627–41 | date = June 1997 | pmid = 9210119 | doi = 10.1044/jslhr.4003.627 }} It is commonly reported by people with spasmodic dysphonia that symptoms almost only occur on vocal sounds that require phonation. Symptoms are less likely to occur at rest, while whispering, or on speech sounds that do not require phonation. It is hypothesized that this occurs because of an increase in sporadic, sudden, and prolonged tension found in the muscles around the larynx during phonation. This tension affects the abduction and adduction (opening and closing) of the vocal folds. Consequently, the vocal folds are unable to retain subglottal air pressure (required for phonation) and breaks in phonation can be heard throughout the speech of people with spasmodic dysphonia.

Regarding types of spasmodic dysphonia, the main characteristic of spasmodic dysphonia, breaks in phonation, is found along with other varying symptoms. The voice quality of adductor spasmodic dysphonia can be described as “strained-strangled” from tension in the glottal region. Voice quality for abductor spasmodic dysphonia can be described as breathy from variable widening of the glottal region. Vocal tremor may also be seen in spasmodic dysphonia. A mix and variance of these symptoms are found in mixed spasmodic dysphonia.

Symptoms of spasmodic dysphonia typically appear in middle-aged people, but have also been seen in people in their twenties, with symptoms emerging as young as teenage years.

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Although the exact cause of spasmodic dysphonia is still unknown, epidemiological, genetic, and neurological pathogenic factors have been proposed in recent research.{{cite journal | vauthors = Hintze JM, Ludlow CL, Bansberg SF, Adler CH, Lott DG | title = Spasmodic Dysphonia: A Review. Part 1: Pathogenic Factors | journal = Otolaryngology–Head and Neck Surgery | volume = 157 | issue = 4 | pages = 551–557 | date = October 2017 | pmid = 28850801 | doi = 10.1177/0194599817728521 }}

Risk factors include:{{cite journal | vauthors = Murry T | title = Spasmodic dysphonia: let's look at that again | journal = Journal of Voice | volume = 28 | issue = 6 | pages = 694–9 | date = November 2014 | pmid = 24972536 | doi = 10.1016/j.jvoice.2014.03.007 }}

• Being female
• Being middle aged
• Having a family history of neurological diseases (e.g., tremor, dystonia, meningitis, and other neurological diseases)
• Stressful events
• Upper respiratory tract infections
• Sinus and throat illnesses
• Heavy voice use
• Cervical dystonia
• Childhood measles or mumps
• Pregnancy and parturition

It has not been established whether these factors directly affect the development of spasmodic dysphonia (SD),{{cite journal | vauthors = Childs L, Rickert S, Murry T, Blitzer A, Sulica L | title = Patient perceptions of factors leading to spasmodic dysphonia: a combined clinical experience of 350 patients | journal = The Laryngoscope | volume = 121 | issue = 10 | pages = 2195–8 | date = October 2011 | pmid = 21898448 | doi = 10.1002/lary.22168 }} however, these factors could be used to identify possible and/or at-risk patients.

Researchers have also explored the possibility of a genetic component to SD. Three genes have been identified that may be related to the development of focal or segmental dystonia: TUBB4A, THAP1, and TOR1A genes.{{cite journal | vauthors = Balint B, Bhatia KP | title = Dystonia: an update on phenomenology, classification, pathogenesis and treatment | journal = Current Opinion in Neurology | volume = 27 | issue = 4 | pages = 468–76 | date = August 2014 | pmid = 24978640 | doi = 10.1097/wco.0000000000000114 }}{{cite journal | vauthors = Lohmann K, Wilcox RA, Winkler S, Ramirez A, Rakovic A, Park JS, Arns B, Lohnau T, Groen J, Kasten M, Brüggemann N, Hagenah J, Schmidt A, Kaiser FJ, Kumar KR, Zschiedrich K, Alvarez-Fischer D, Altenmüller E, Ferbert A, Lang AE, Münchau A, Kostic V, Simonyan K, Agzarian M, Ozelius LJ, Langeveld AP, Sue CM, Tijssen MA, Klein C | title = Whispering dysphonia (DYT4 dystonia) is caused by a mutation in the TUBB4 gene | journal = Annals of Neurology | volume = 73 | issue = 4 | pages = 537–45 | date = April 2013 | pmid = 23595291 | doi = 10.1002/ana.23829 | pmc = 6956988 }}{{cite journal | vauthors = Fuchs T, Gavarini S, Saunders-Pullman R, Raymond D, Ehrlich ME, Bressman SB, Ozelius LJ | title = Mutations in the THAP1 gene are responsible for DYT6 primary torsion dystonia | journal = Nature Genetics | volume = 41 | issue = 3 | pages = 286–8 | date = March 2009 | pmid = 19182804 | doi = 10.1038/ng.304 }} However, a recent study that examined the mutation of these three genes in 86 SD patients found that only 2.3% of the patients had novel/rare variants in THAP1, but none in TUBB4A and TOR1A.{{cite journal | vauthors = de Gusmão CM, Fuchs T, Moses A, Multhaupt-Buell T, Song PC, Ozelius LJ, Franco RA, Sharma N | title = Dystonia-Causing Mutations as a Contribution to the Etiology of Spasmodic Dysphonia | journal = Otolaryngology–Head and Neck Surgery | volume = 155 | issue = 4 | pages = 624–8 | date = October 2016 | pmid = 27188707 | pmc = 5536965 | doi = 10.1177/0194599816648293 }} Evidence of a genetic contribution for dystonia involving the larynx is still weak, and more research is needed in order to establish a causal relationship between SD and specific genes.

SD is a neurological disorder rather than a disorder of the larynx, and as in other forms of dystonia, interventions at the end organ (i.e., larynx) have not offered a definitive cure, only symptomatic relief. The pathophysiology underlying dystonia is becoming better understood as a result of discoveries about genetically based forms of the disorder, and this approach is the most promising avenue to a long-term solution.{{cite journal | vauthors = Sulica L | title = Contemporary management of spasmodic dysphonia | journal = Current Opinion in Otolaryngology & Head and Neck Surgery | volume = 12 | issue = 6 | pages = 543–8 | date = December 2004 | pmid = 15548915 | doi = 10.1097/01.moo.0000145959.50513.5e }}

SD is classified as a neurological disorder.[http://www.ninds.nih.gov/disorders/dystonias/detail_dystonias.htm Dystonias Fact Sheet: National Institute of Neurological Disorders and Stroke (NINDS)] {{webarchive|url=https://web.archive.org/web/20061205011715/http://ninds.nih.gov/disorders/dystonias/detail_dystonias.htm |date=2006-12-05 }} However, because the voice can sound normal or near normal at times, some practitioners believe it to be psychogenic; that is, originating in the affected person's mind rather than from a physical cause.{{cite journal | vauthors = Kaye R, Blitzer A | title = Chemodenervation of the Larynx | journal = Toxins | volume = 9 | issue = 11 | pages = 356 | date = November 2017 | pmid = 29099066 | pmc = 5705971 | doi = 10.3390/toxins9110356 | doi-access = free }} This was especially true in the 19th and 20th centuries. No medical organizations or groups take this position. A comparison of SD patients compared with vocal fold paralysis (VFP) patients found that 41.7% of the SD patients met the DSM-IV criteria for psychiatric comorbidity compared with 19.5% of the VFP group.{{cite journal | vauthors = Gündel H, Busch R, Ceballos-Baumann A, Seifert E | title = Psychiatric comorbidity in patients with spasmodic dysphonia: a controlled study | journal = Journal of Neurology, Neurosurgery, and Psychiatry | volume = 78 | issue = 12 | pages = 1398–400 | date = December 2007 | pmid = 17615166 | pmc = 2095627 | doi = 10.1136/jnnp.2007.121699 }} However, another study found the opposite, with SD patients having significantly less psychiatric comorbidity compared to VFP patients: "The prevalence of major psychiatric cases varied considerably among the groups, from a low of seven percent (1/14) for spasmodic dysphonia, to 29.4 percent (5/17) for functional dysphonia, to a high of 63.6 percent (7/11) for vocal cord paralysis."[http://www.newswise.com/articles/view/25781/ Newswise Medical News | Patients with Selected Voice Disorders Are Subject to Psychiatric Problems] {{webarchive|url=https://web.archive.org/web/20080802050357/http://www.newswise.com/articles/view/25781/ |date=2008-08-02 }} A review in the journal Swiss Medicine Weekly states that "Psychogenic causes, a 'psychological disequilibrium', and an increased tension of the laryngeal muscles are presumed to be one end of the spectrum of possible factors leading to the development of the disorder”.{{cite journal | vauthors = Seifert E, Kollbrunner J | title = Stress and distress in non-organic voice disorder | journal = Swiss Medical Weekly | volume = 135 | issue = 27–28 | pages = 387–97 | date = July 2005 | doi = 10.4414/smw.2005.10346 | pmid = 16220409 | doi-access = free }} Alternatively, many investigations into the condition feel that the psychiatric comorbidity associated with voice disorders is a result of the social isolation and anxiety that patients with these conditions feel as a consequence of their difficulty with speech, as opposed to the cause of their dysphonia.{{cite journal |last1=Langeveld |first1=Ton P. M. |last2=Luteijn |first2=Frans |last3=Drost |first3=Harm A. |last4=van Rossum |first4=Maya |last5=de Jong |first5=Robert J. Baatenburg |title=Adductor Spasmodic Dysphonia and Botulinum Toxin Treatment: The Effect on Well-Being |journal=Annals of Otology, Rhinology & Laryngology |date=October 2001 |volume=110 |issue=10 |pages=941–945 |doi=10.1177/000348940111001009 |pmid=11642427 }} The opinion that SD is psychogenic is not upheld by experts in the scientific community.[http://www.dysphonia.org/src/neuro.pdf Spasmodic Dysphonia is a Neurological Disorder Current Evidence and References] {{webarchive|url=https://web.archive.org/web/20110206000255/http://www.dysphonia.org/src/neuro.pdf |date=2011-02-06 }}, by Christy L. Ludlow, Ph.D.

SD is formally classified as a movement disorder; it is a type of focal dystonia known as laryngeal dystonia.{{cite journal | vauthors = Merati AL, Heman-Ackah YD, Abaza M, Altman KW, Sulica L, Belamowicz S | title = Common movement disorders affecting the larynx: a report from the neurolaryngology committee of the AAO-HNS | journal = Otolaryngology–Head and Neck Surgery | volume = 133 | issue = 5 | pages = 654–65 | date = November 2005 | pmid = 16274788 | doi = 10.1016/j.otohns.2005.05.003 }}

Diagnosis of spasmodic dysphonia requires a multidisciplinary team and consideration of both perceptual and physiological factors.{{cite journal | vauthors = Hintze JM, Ludlow CL, Bansberg SF, Adler CH, Lott DG | title = Spasmodic Dysphonia: A Review. Part 2: Characterization of Pathophysiology | journal = Otolaryngology–Head and Neck Surgery | volume = 157 | issue = 4 | pages = 558–564 | date = October 2017 | pmid = 28850796 | doi = 10.1177/0194599817728465 }} There is currently no universally accepted diagnostic test for spasmodic dysphonia, which presents a challenge for diagnosis.{{cite journal |last1=Whurr |first1=Renata |last2=Lorch |first2=Marjorie |title=Review of differential diagnosis and management of spasmodic dysphonia |journal=Current Opinion in Otolaryngology & Head and Neck Surgery |date=June 2016 |volume=24 |issue=3 |pages=203–207 |doi=10.1097/MOO.0000000000000253 |pmid=26900821 |url=https://eprints.bbk.ac.uk/id/eprint/14204/1/14204.pdf }} Additionally, diagnostic criteria have not been agreed upon as the distinguishing features of this disorder have not been well-characterized.

A team of professionals including a speech–language pathologist, an otolaryngologist, and a neurologist, are typically involved in spasmodic dysphonia assessment and diagnosis.{{cite web|url=https://www.asha.org/public/speech/disorders/SpasmodicDysphonia/|title=Spasmodic Dysphonia|website=www.asha.org |access-date=2017-11-05}} The speech–language pathologist conducts a speech assessment including case history questions to gather information about voice use and symptoms. This is followed by clinical observation and perceptual rating of voice characteristics such as voice breaks or strain, which are selectively present in normal speech over other voice activities such as whispering or laughing. Symptoms also vary across types of spasmodic dysphonia. For example, voiced sounds are more affected in adductor spasmodic dysphonia, while unvoiced sounds are more affected in abductor spasmodic dysphonia. Following the speech assessment, the otolaryngologist conducts a flexible transnasal laryngoscopy to view the vocal folds and activity of the muscles controlling them in order to eliminate other possible causes of the voice disorder. In spasmodic dysphonia, producing long vowels or speaking sentences results in muscle spasms that are not observed during other vocal activities such as coughing, breathing, or whispering. To evaluate the individual for any other neurological problems, this examination is followed up with an assessment by the neurologist.

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Because spasmodic dysphonia shares many characteristics with other voice disorders, misdiagnosis frequently occurs. A common misdiagnosis is muscle tension dysphonia, a functional voice disorder that results from use of the voice, rather than a structural abnormality.{{cite journal|vauthors=Hintze JM, Ludlow CL, Bansberg SF, Adler CH, Lott DG|date=October 2017|title=Spasmodic Dysphonia: A Review. Part 2: Characterization of Pathophysiology|journal=Otolaryngology–Head and Neck Surgery|volume=157|issue=4|pages=558–564|doi=10.1177/0194599817728465|pmid=28850796 }} Some parameters can help guide the clinician towards a decision. In muscle tension dysphonia, the vocal folds are typically hyperadducted in a constant way, not in a spasmodic way.{{cite journal|last=Sulica|first=Lucian|date=December 2004|title=Contemporary management of spasmodic dysphonia|journal=Current Opinion in Otolaryngology & Head and Neck Surgery |volume=12|issue=6|pages=543–548|doi=10.1097/01.moo.0000145959.50513.5e |pmid=15548915 }} Additionally, the voice difficulties found in spasmodic dysphonia can be task specific, as opposed to those found in muscle tension dysphonia. Being able to differentiate between muscle tension dysphonia and spasmodic dysphonia is important because muscle tension dysphonia typically responds well to behavioral voice treatment, but spasmodic dysphonia does not. This is crucial to avoid providing inappropriate treatment, but in some cases, a trial of behavioral voice treatment can also be helpful to establish a differential diagnosis.

Spasmodic dysphonia can also be misdiagnosed as voice tremor. The movements that are found in this disorder are typically rhythmic in nature, as opposed to the muscle spasms of spasmodic dysphonia. It is important to note that voice tremor and spasmodic dysphonia can co-occur in some patients.

Differential diagnosis is particularly important for determining appropriate interventions, as the type and cause of the disorder determine the most effective treatment. Differences in treatment effectiveness are present even between the types of spasmodic dysphonia. Diagnosis of spasmodic dysphonia is often delayed due to these challenges, which in turn presents difficulties in choosing the proper interventions.

The three types of spasmodic dysphonia (SD) are adductor spasmodic dysphonia, abductor spasmodic dysphonia, and mixed spasmodic dysphonia. A fourth type called whispering dysphonia has also been proposed.{{cite journal | vauthors = Parker N | title = Hereditary whispering dysphonia | journal = Journal of Neurology, Neurosurgery, and Psychiatry | volume = 48 | issue = 3 | pages = 218–24 | date = March 1985 | pmid = 3156966 | pmc = 1028253 | doi=10.1136/jnnp.48.3.218}} Adductor spasmodic dysphonia is the most common type.{{cite journal | vauthors = Woodson G, Hochstetler H, Murry T | title = Botulinum toxin therapy for abductor spasmodic dysphonia | journal = Journal of Voice | volume = 20 | issue = 1 | pages = 137–43 | date = March 2006 | pmid = 16126369 | doi = 10.1016/j.jvoice.2005.03.008 }}

Adductor spasmodic dysphonia (ADSD) is the most common type, affecting around 87% of individuals with SD. In ADSD, sudden involuntary muscle movements or spasms cause the vocal folds (or vocal cords) to squeeze together and stiffen.{{cite web | url = http://www.medterms.com/script/main/art.asp?articlekey=13856 | title = Definition of Spasmodic dysphonia | access-date = 2007-05-11 | work = MedTerms medical dictionary | publisher = MedicineNet.com | url-status = dead | archive-url = https://web.archive.org/web/20070927203946/http://www.medterms.com/script/main/art.asp?articlekey=13856 | archive-date = 2007-09-27 }} As the name suggests, these spasms occur in the adductor muscles of the vocal folds, specifically the thyroarytenoid and the lateral cricoarytenoid. These spasms make it difficult for the vocal folds to vibrate and produce voice. Words are often cut off or are difficult to start because of the muscle spasms. Therefore, speech may be choppy but differs from stuttering. The voice of an individual with adductor spasmodic dysphonia is commonly described as strained or strangled and full of effort. Surprisingly, the spasms are usually absent while laughing, speaking at a high pitch, or speaking while singing, but singers can experience a loss of range or the inability to produce certain notes of a scale or with projection. Stress, however, often makes the muscle spasms more severe.{{cite web | url = https://www.nidcd.nih.gov/health/spasmodic-dysphonia | title = Spasmodic Dysphonia | access-date = 2016-07-09 | work = Publication No. 10-4214 | publisher = National Institute on Deafness and Other Communication Disorders| date = 2015-08-18 }}Includes text taken directly from the website. As a work of the National Institutes of Health, part of the United States Department of Health and Human Services, this text constitutes a work of the U.S. federal government, therefore it is in the public domain.

Abductor spasmodic dysphonia (ABSD) is the second most common type, affecting around 13% of individuals with SD. In ABSD, sudden involuntary muscle movements or spasms cause the vocal folds to open. As the name suggests, these spasms occur in the single abductor muscle of the vocal folds, called the posterior cricoarytenoid. The vocal folds cannot vibrate when they are open. The open position of the vocal folds also allows air to escape from the lungs during speech. As a result, the voices of these individuals often sound weak, quiet, and breathy or whispery. As with adductor spasmodic dysphonia, the spasms are often absent during activities such as laughing or singing, but singers can experience a loss of range or the inability to produce certain notes of a scale or with projection.

Mixed spasmodic dysphonia is the most rare type. Mixed spasmodic dysphonia involves both muscles that open the vocal folds and those that close them and, therefore, has features of both adductor and abductor spasmodic dysphonia. Some researchers believe that a subset of cases classified as mixed spasmodic dysphonia may actually be ADSD or ABSD subtype with the addition of compensatory voice behaviors that make it appear mixed. This further adds to the difficulty in achieving accurate diagnosis.

A fourth type has also been described. This appears to be caused by mutations in the TUBB4 gene on the short arm of chromosome 19 (19p13.2–p13.3). This gene encodes a tubulin gene. The pathophysiology of this condition has yet to be determined.

There are a number of potential treatments for spasmodic dysphonia, including Botox, voice therapy, and surgery. A number of medications have also been tried including anticholinergics (such as benztropine) which have been found to be effective in 40–50% of people, but which are associated with a number of side effects.{{cite journal | vauthors = Grillone GA, Chan T | title = Laryngeal dystonia | journal = Otolaryngologic Clinics of North America | volume = 39 | issue = 1 | pages = 87–100 | date = February 2006 | pmid = 16469657 | doi = 10.1016/j.otc.2005.11.001 }}

Botulinum toxin (Botox) is often used to improve some symptoms of spasmodic dysphonia through weakening or paralyzing the vocal folds, thus preventing muscle spasms. The level of evidence for its use is currently limited; little is known about optimal dosage, frequency of injections, or exact location of injection.{{cite journal | vauthors = Watts C, Nye C, Whurr R | title = Botulinum toxin for treating spasmodic dysphonia (laryngeal dystonia): a systematic Cochrane review | journal = Clinical Rehabilitation | volume = 20 | issue = 2 | pages = 112–122 | date = 2006 | pmid = 16541931 | doi = 10.1191/0269215506cr931oa }}{{cite journal|last1=Watts|first1=C. C. W.|last2=Whurr|first2=R.|last3=Nye|first3=C.|date=2004|title=Botulinum toxin injections for the treatment of spasmodic dysphonia|journal=The Cochrane Database of Systematic Reviews|volume=2010|issue=3|pages=CD004327|doi=10.1002/14651858.CD004327.pub2 |pmid=15266530|pmc=8805439}} However, it remains a choice for many people due to the predictability and low chance of long term side effects. It results in periods of some improvement, with the duration of benefit lasting for 10–12 weeks on average before symptoms return to baseline. Repeat injection is required to sustain good vocal production, as results are only temporary.{{cite journal | vauthors = Ludlow CL | title = Treatment for spasmodic dysphonia: limitations of current approaches | journal = Current Opinion in Otolaryngology & Head and Neck Surgery | volume = 17 | issue = 3 | pages = 160–165 | date = 2009 | pmid = 19337127 | pmc = 2763389 | doi = 10.1097/MOO.0b013e32832aef6f }}{{cite journal | vauthors = van Esch BF, Wegner I, Stegeman I, Grolman W | title = Effect of Botulinum Toxin and Surgery among Spasmodic Dysphonia Patients | journal = Otolaryngology–Head and Neck Surgery | volume = 156 | issue = 2 | pages = 238–254 | date = 2017 | pmid = 27803079 | doi = 10.1177/0194599816675320 | url = https://research.rug.nl/en/publications/5676434c-f991-4fde-8fdc-7fc9602408d1 }} Some transient side effects observed in adductor spasmodic dysphonia include reduced speaking volume, difficulty swallowing, and a breathy and hoarse voice quality.{{cite journal |last1=Boutsen |first1=Frank |last2=Cannito |first2=Michael P. |last3=Taylor |first3=Merlin |last4=Bender |first4=Brenda |title=Botox Treatment in Adductor Spasmodic Dysphonia: A Meta-Analysis |journal=Journal of Speech, Language, and Hearing Research |date=June 2002 |volume=45 |issue=3 |pages=469–481 |doi=10.1044/1092-4388(2002/037) |pmid=12069000 }} While treatment outcomes are generally positive, it is presently unclear whether this treatment approach is more or less effective than others.

Voice therapy appears to be ineffective in cases of true spasmodic dysphonia.{{cite journal | vauthors = Chhetri DK, Berke GS | title = Treatment of adductor spasmodic dysphonia with selective laryngeal adductor denervation and reinnervation surgery | journal = Otolaryngologic Clinics of North America | volume = 39 | issue = 1 | pages = 101–9 | date = February 2006 | pmid = 16469658 | doi = 10.1016/j.otc.2005.10.005 }} However, as it is difficult to distinguish between spasmodic dysphonia and functional dysphonias, and misdiagnosis is relatively common,{{cite book |last1=Warner |first1=Thomas T. |last2=Bressman |first2=Susan B. |title=Clinical Diagnosis and Management of Dystonia |date=2007 |publisher=CRC Press |isbn=978-0-203-64048-7 |page=111 |url=https://books.google.com/books?id=haKD-PjEJ3MC&pg=PA111 }} trial of voice therapy is often recommended before more invasive procedures are tried. Some also state that it is useful for mild symptoms and as an add-on to botox therapy{{cite book |last1=Ballenger |first1=John Jacob |title=Ballenger's Otorhinolaryngology: Head and Neck Surgery |date=2009 |publisher=BC Decker |isbn=978-1-55009-337-7 |page=918 |url=https://books.google.com/books?id=sGhzMnst1j8C&pg=PA918 }} and others report success in more severe cases.{{cite book |last1=Stemple |first1=Joseph C. |last2=Glaze |first2=Leslie E. |last3=Gerdeman |first3=Bernice K. |last4=Klaben |first4=Bernice |title=Clinical Voice Pathology: Theory and Management |date=2000 |publisher=Singular Publishing Group |isbn=978-0-7693-0005-4 |page=368 |url=https://books.google.com/books?id=y2UboKGPCNIC&pg=PA368 }} Laryngeal manual therapy, which is massaging of the neck and cervical structures, also shows positive results for intervention of functional dysphonia.{{cite journal | vauthors = Ribeiro VV, Pedrosa V, Silverio KC, Behlau M | title = Laryngeal Manual Therapies for Behavioral Dysphonia: A Systematic Review and Meta-analysis | journal = Journal of Voice | volume = 32 | issue = 5 | pages = 553–563 | date = September 2018 | pmid = 28844806 | doi = 10.1016/j.jvoice.2017.06.019 }}

If other measures are not effective, surgery may be considered; however, evidence to support surgery as a treatment for SD is limited. Treatment outcomes are generally positive, though more research is required to determine its effectiveness. Post-surgery voices can be imperfect and about 15% of people have significant difficulties. If symptoms do recur, this typically happens in the first 12 months. {{As of|2011}}, surgery was rarely used as a treatment approach for SD.{{cite book |last1=Fahn |first1=Stanley |last2=Jankovic |first2=Joseph |last3=Hallett |first3=Mark |title=Principles and Practice of Movement Disorders E-Book |date=2011 |publisher=Elsevier Health Sciences |isbn=978-1-4377-3770-7 |page=309 |url=https://books.google.com/books?id=OkXsXr2HKPwC&pg=PA309 }} Surgical approaches include recurrent laryngeal nerve resection, selective laryngeal adductor denervation-reinnervation (SLAD-R), thyroplasty, thyroarytenoid myectomy, and laryngeal nerve crush. Recurrent laryngeal nerve resection involves removing a section of the recurrent laryngeal nerve.{{cite book |title=Diagnosis and treatment of voice disorders |last1=Rubin |first1=John S. |last2=Sataloff |first2=Robert Thayer |last3=Korovin |first3=Gwen S. |isbn=978-1-597-56644-5 |edition=4th |location=San Diego, CA |publisher=Plural Publishing |oclc=885595880 |date=2014 }} Recurrent laryngeal nerve avulsion is a more drastic removal of sections of the nerve, and has positive outcomes of 80% at three years. SLAD-R is effective specifically for adductor spasmodic dysphonia, for which it has shown good outcomes in about 80% of people at 8 years. Thyroplasty changes the position or length of the vocal folds.

In 1871, Ludwig Traube coined the term 'Spastic Dysphonia' while writing a description of a patient who suffered from a nervous hoarseness.{{Cite book |last1=Traube |first1=Ludwig |url=https://books.google.com/books?id=MjMAAAAAQAAJ&pg=PA1 |title=Gesammelte Beiträge zur Pathologie und Physiologie |last2=Fränkel |date=1871 |publisher=Hirschwald |language=de}}

In 1895, Johann Schnitzler used the term "Spastic Aphonia", which is now called abductor SD, and "Phonic Laryngeal Spasms", now called adductor SD.{{Cite book |last=Schnitzler |first=Johann |url=https://books.google.com/books?id=hBkdUFBIYBsC&pg=PA1 |title=Klinischer Atlas der Laryngologie nebst Anleitung zur Diagnose und Therapie der Krankeiten des Kehlkopfes und der Luftröhre |date=1895 |publisher=W. Braumüller |language=de}}

Hermann Nothnagel followed by calling the condition "Coordinated Laryngeal Spasms", while Fraenkel coined the term "Mogiphonia" as a slowly developing disorder of the voice, in which is characterized by the increasing of vocal fatigue, the spasmodic constriction of the thorat muscles, and pain around the larynx. A comparison was made to "mogigraphia", which we now know as "Writer's Cramp".

In 1899, William Gowers described functional laryngeal spasms whereby the vocal cords were brought together with too much force while speaking. This was contrasted to Phonic Paralysis, where the speaker's vocal chords could not be brought together during the action of speech. He reported in agreement with Fraenkel, that the vocal symptoms are most closely compared to Writers Cramp. Gowers reported and described a case by Gerhardt, where the patient had suffered from Writer's Cramp, and had learned to play the flute at the age of 50. Blowing the flute caused laryngeal spasms and a voice sound unintended by the patient, accompanied by contractions of the arm and mouth.{{Cite book |last=Gowers |first=William Richard |url=https://books.google.com/books?id=TyFAAQAAIAAJ&pg=PA1 |title=A Manual of Diseases of the Nervous System |date=1898 |publisher=P. Blakiston, Son & Company |pages=294 }}

This disorder was termed "Spastic Dysphonia", and as it was not a disorder with spasticity, was re-named to what is now called, "Spasmodic Dysphonia", by Arnold Aronson in 1968.{{cite journal |last1=Aronson |first1=Arnold E. |last2=Brown |first2=Joe R. |last3=Litin |first3=Edward M. |last4=Pearson |first4=John S. |title=Spastic Dysphonia. II. Comparison with Essential (Voice) Tremor and Other Neurologic and Psychogenic Dysphonias |journal=Journal of Speech and Hearing Disorders |date=August 1968 |volume=33 |issue=3 |pages=219–231 |doi=10.1044/jshd.3303.219 |pmid=5668051 }}

In earlier works, Aronson performed Minnesota Multiphasic Personality Inventory screening and helped to establish SD as not being a Psychiatric Disorder, after reviewing psychiatric interviews of SD patients. Aronson formally characterized the two types of SD, the adductor, and abductor forms. Aronson described that adductor SD suffered from decreased loudness, and a mono-tonality, with a choked, strain-strangled voice quality. A vocal tremor was also often heard with a slowed speech rate. this was compared to what is seen in Essential Tremor.{{Cite journal |last1=Blitzer |first1=Andrew |last2=Brin |first2=Mitchell F. |last3=Simonyan |first3=Kristina |last4=Ozelius |first4=Laurie J |last5=Frucht |first5=Steven J |date=January 2018 |title=Phenomenology, Genetics and CNS network abnormalities in Laryngeal Dystonia: a 30 year experience |journal=The Laryngoscope |volume=128 |issue=Suppl 1 |pages=S1–S9 |doi=10.1002/lary.27003 |pmc=5757628 |pmid=29219190}}

Initial surgical efforts to treat the condition were published in 1976 by Herbert Dedo and involved cutting of the recurrent laryngeal nerve.{{cite journal |last1=Dedo |first1=Herbert H. |title=Recurrent Laryngeal Nerve Section for Spastic Dysphonia |journal=Annals of Otology, Rhinology & Laryngology |date=1976 |volume=85 |issue=4 |pages=451–459 |doi=10.1177/000348947608500405 |pmid=949152 }}

• Scott Adams, creator of the comic strip Dilbert{{cite web |date=2006-10-27 |title='Dilbert' creator recovers from rare disorder |url=http://www.nbcnews.com/id/15446515 |url-status=dead |archive-url=https://web.archive.org/web/20131220053437/http://www.nbcnews.com/id/15446515 |archive-date=2013-12-20 |access-date=2007-07-30 |website=NBC News |agency=Associated Press}}
• Johnny Bush, country and western musician and songwriter{{cite news |first= Jim |last= Beal |title= Golden country Johnny Bush hasn't run dry after almost 50 years of heartaches and honky-tonks |url= http://nl.newsbank.com/nl-search/we/Archives?p_product=SAEC&p_theme=saec&p_action=search&p_maxdocs=200&p_topdoc=1&p_text_direct-0=0EAFE8396F19EF1A&p_field_direct-0=document_id&p_perpage=10&p_sort=YMD_date:D&s_trackval=GooglePM |work= San Antonio Express-News |date= 1998-04-29}}
• Keath Fraser, Canadian author who has documented the challenges and treatment of his condition in the book The Voice Gallery: Travels With a Glass Throat (2002)[http://www.thomas-allen.com/ThomasAllenPublishers/catalogue/0-88762-101-5.htm The Voice Gallery - Thomas Allen Publishers - Thomas Allen & Son Limited] {{webarchive|url=https://web.archive.org/web/20071019023854/http://www.thomas-allen.com/ThomasAllenPublishers/catalogue/0-88762-101-5.htm |date=2007-10-19 }}{{cite news |title=The Voice Gallery: Travels with a Glass Throat {{!}} Quill and Quire |url=https://quillandquire.com/review/the-voice-gallery-travels-with-a-glass-throat/ |access-date=11 August 2018 |work=Quill and Quire |date=21 January 2004}}
• Chip Hanauer, American hydroplane racing driver{{cite web|url=http://uwnews.washington.edu/ni/article.asp?articleID=1607|title=Chip Hanauer's restored voice gives him a new lease on life|last1=McHale|first1=Laurie|last2=Degginger|first2=Craig|date=May 14, 1999|publisher=University of Washington News and Information|access-date=September 22, 2012|url-status=dead|archive-url=https://archive.today/20121215060937/http://uwnews.washington.edu/ni/article.asp?articleID=1607|archive-date=December 15, 2012}}
• Rodney Hicks, American Broadway, film, and TV performer{{cite web |last=Hetrick |first=Adam |date=August 1, 2017 |title=Actor Rodney Hicks Opens Up About Come From Away Departure |url=https://www.playbill.com/article/actor-rodney-hicks-opens-up-about-come-from-away-departure |access-date=July 18, 2023 |website=Playbill}}
• Kaori, Japanese voice actor[https://web.archive.org/web/20120531232201/http://spunkystrider.good.cx/news_kaori/index.html ☆いつも応援してくれているファンの皆さんへ☆]
• Robert F. Kennedy Jr. 26th Secretary of Health and Human Services{{cite web |url= https://www.nytimes.com/2006/06/25/fashion/25bobby.html |title= Another Kennedy Living Dangerously |access-date= 2007-07-30 |last= Liebovich |first= Mark |date= 2006-06-25 |work= The New York Times |url-status= live |archive-url= https://web.archive.org/web/20080407021909/http://www.nytimes.com/2006/06/25/fashion/25bobby.html |archive-date= 2008-04-07 }}
• Mary Lou Lord, indie folk musician{{cite news |first= Jim |last= Sullivan |title= Hello, Mary Lou – Goodbye, Heartache |url= http://nl.newsbank.com/nl-search/we/Archives?p_product=BG&p_theme=bg&p_action=search&p_maxdocs=200&p_topdoc=1&p_text_direct-0=100D6882D4430C7F&p_field_direct-0=document_id&p_perpage=10&p_sort=YMD_date:D&s_trackval=GooglePM |work= Boston Globe |date= 2004-02-19}}
• Andy MacWilliams, radio broadcaster for the Cincinnati Stingers, Chicago Black Hawks, and Cincinnati Cyclones.
• Benny Martin (1928–2001), American bluegrass fiddler, affected from 1980 to 1997{{cite web |title=Benjamin Edward "Benny" Martin |url=https://www.bluegrasshall.org/inductees/benjamin-edward-benny-martin/ |website=Bluegrass Music Hall of Fame |date=8 June 2018 |access-date=2021-09-01}}
• Darryl McDaniels of the rap group Run DMC{{cite news |first= Virginia |last= Heffernan |title= After the Hit Records, A Search for His Roots |work= The New York Times |date= 2006-02-25}}
• Jenny Morris, New Zealand-born Australian pop, rock singer-songwriter{{cite news|last1=Clarke|first1=Jenna|title=The reason why '90s pop star Jenny Morris disappeared|url=https://www.smh.com.au/lifestyle/celebrity/ls-celebrity-news/the-reason-why-90s-pop-star-jenny-morris-disappeared-20151009-gk5q0o.html|newspaper=Sydney Morning Herald|url-status=live|archive-url=https://web.archive.org/web/20151011182549/http://www.smh.com.au/lifestyle/celebrity/ls-celebrity-news/the-reason-why-90s-pop-star-jenny-morris-disappeared-20151009-gk5q0o.html|archive-date=2015-10-11}}Australian Story (Series 2015; Episode 37) - Raise Your Voice, Australian Broadcasting Corporation (ABC). First aired Monday 12 October 2015.
• Petra Pau, one of the vice-presidents of the German Bundestag.{{cite news|last= Hollstein|first=Miriam|title=Als Petra Pau plötzlich ihre Stimme verlor|url=https://www.welt.de/article111895283/|language=de|trans-title=When Petra Pau Suddenly Lost Her Voice|newspaper=Die Welt|location=Berlin |date=10 December 2012}}
• Jeff Pegues, Chief National Affairs and Justice Correspondent at CBS News{{cite news|url= https://www.cbsnews.com/news/how-a-cbs-news-correspondents-anxiety-almost-cost-him-his-voice/ |title= How a CBS News correspondent's anxiety almost cost him his voice |last=Cannella |first=Greg |date=26 July 2021 |access-date=23 November 2022}}
• Diane Rehm, American public radio talk show host{{cite news|url=http://www.washingtonpost.com/wp-srv/style/features/daily/rehm0823.htm |title=Diane Rehm Finds a Voice of Her Own |last=Weeks |first=Linton |newspaper=Washington Post |date=August 23, 1999 |access-date=May 2, 2019}}
• Aleesha Rome, causing her to quit her singing career.
• Gail Strickland, an American actress{{Citation |title=Introduction to Gail Strickland | date=May 2022 |url=https://www.youtube.com/watch?v=0Ksyt4XOyOM |access-date=2023-12-20 }}
• Mark Stuart, American Christian rock musician, of Audio Adrenaline{{cite magazine|url=https://www.billboard.com/articles/news/1551812/audio-adrenaline-begin-new-chapter-with-pop-tinged-kings-queens |title=Audio Adrenaline Begin New Chapter With Pop-Tinged 'Kings & Queens' |last=Price |first=Deborah Evans |magazine=Billboard |date=March 13, 2013 |access-date=March 23, 2019}}
• Linda Thompson, British folk-rock musician{{cite web |url=http://www.nowtoronto.com/issues/2002-10-17/music_feature3.php |title=Thompson's Trials: UK Folk Rock Great Makes Triumphant Return to the Stage |access-date=2007-08-23 |date=2002-10-17 |work=Tim Perlich, NOW Toronto |url-status=dead |archive-url=https://web.archive.org/web/20070929124615/http://www.nowtoronto.com/issues/2002-10-17/music_feature3.php |archive-date=2007-09-29 }}

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Category:Voice disorders

Category:Wikipedia medicine articles ready to translate

Category:Wikipedia neurology articles ready to translate