Spasmodic Dysphonia
Evaluation and Management
UTMB Department of Otolaryngology
Olvia Revelo, MSIV
Faculty Advisor:Michael Underbrink, MD
Grand Rounds Presentation
March 10, 2009
Overview
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Introduction
Anatomy of the larynx
Etiology
Diagnosis
Clinical features
Therapy
Pharmacologic
 Surgical
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Conclusion
Introduction
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Spasmodic dysphonia (SD)
Focal, adult-onset dystonia of laryngeal muscles
 Intermittent phonatory breaks during speech
secondary to spasms
 Usually task specific - symptomatic when attempting
voluntary speech
 May be asymptomatic during reflexive phonation
(coughing, laughing, crying, yawning)
 Symptoms reduced/absent during singing or
whisper
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Associations
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May be associated with:
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Other focal dystonias
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Underlying neurological
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Parkinson’s, ALS
Environmental
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Blepharospasms, Torticollis, Writer’s Cramp
Infection, trauma, meds
Psychogenic stimulus
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Stress
Demographics
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Affects approximately
1:10,000 Americans
Female to male ratio 3:1
up to 8:1
Peak age of onset 35-45
Positive family history in
12% of affected pt’s
Types of Laryngeal Dystonias
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Adductor – irregular hyperadduction of vocal
folds with excessive glottic closure
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Abductor – incomplete, irregular vocal fold
approximation
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Mixed – both elements are present
Anatomy: Laryngeal Cartilage
Netter
Anatomy: Laryngeal Cartilage
Netter
Anatomy: Laryngeal Muscles
Netter
Anatomy: Laryngeal Muscles
Netter
Anatomy: Laryngeal Motion
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Abduction of vocal ligament
Netter
Anatomy: Laryngeal Motion
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Adduction of vocal ligament
Netter
Anatomy: Laryngeal Motion
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Tension of vocal ligament
Netter
Anatomy: Laryngeal Innervation
Netter
Etiology
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Currently unknown
Historically psychogenic disorder
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Traube 1871 “nervous hoarseness”
Current theory involves neurologic cause
Basal ganglia involved in other focal dystonias
 Some patients have developed SD post head trauma
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Diagnosis
Diagnosis is based on history and examination
of the glottis during various laryngeal tasks.
 Aronson defined “idiopathic spastic dysphonia”:
1. The voice signs of SD
2. Absence of VC lesions/paralysis
3. Normal peripheral speech mechanisms
4. Resistance of symptoms to voice therapy and
psychotherapy
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Clinical Features: Adductor Type
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Most common ~85% of diagnosed cases
Choked, strained-strangled voice, with abrupt
breaks in phonation in the middle of vowels
Breaks are due to hyper-adduction of the folds
Difficulty with “We eat eels every day” and
“We mow our lawn all year”
Clinical features: Abductor Type
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Rare ~15% of patients with SD
Breathy, effortful voice with abrupt breaks
resulting in whispered elements of their speech.
Excessive and prolonged abduction during
voiceless consonants (/h/,/s/,/f/,/p/,/t/,/k/)
Difficulty with “The puppy bit the tape” and
“When he comes home we’ll feed him”
Mixed Type
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Extremely rare, with symptoms of both
adductor and abductor type
Diagnosis important for predicting treatment
response
Diagnosis
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Electromyography
Fiberoptic laryngoscopy
Videostroboscopy
Aerodynamic testing
Vocal spectrographic analysis
Therapy
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Pharmacotherapy
Botox
 Neuropharmacologic
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Voice Therapy
Surgical
Recurrent laryngeal nerve section
 Recurrent laryngeal nerve avulsion
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Therapy
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Surgical - Experimental
Recurrent laryngeal nerve denervation and
reinnervation
 Type II thyroplasty
 Posterior cricoarytenoid myoplasty with
medialization thyroplasty
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Botulinum Toxin
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Goldstandard treatment for SD
Prevents presynaptic release of acetylcholine
(Ach) at neuromuscular junction.
Different serotypes of botulinum toxin exhibit
specific proteolysis of proteins involved in
transport and binding of Ach vesicles to
presynaptic membrane.
Result in temporary paralysis
Botox mechanism of action
Release of acetylcholine at the neuromuscular junction is mediated by the
assembly of a synaptic fusion complex that allows the membrane of the
synaptic vesicle containing acetylcholine to fuse with the neuronal cell
membrane. The synaptic fusion complex is a set of SNARE proteins, which
include synaptobrevin, SNAP-25, and syntaxin. After membrane fusion,
acetylcholine is released into the synaptic cleft and then bound by receptors
on the muscle cell.
JAMA. 2001;285:1059-1070
Botox mechanism of action
Botulinum toxin binds to the neuronal cell membrane at the nerve terminus and enters the
neuron by endocytosis. The light chain of botulinum toxin cleaves specific sites on the
SNARE proteins, preventing complete assembly of the synaptic fusion complex and thereby
blocking acetylcholine release. Botulinum toxins types B, D, F, and G cleave synaptobrevin;
types A, C, and E cleave SNAP-25; and type C cleaves syntaxin. Without acetylcholine
release, the muscle is unable to contract.
Botulinum Toxin
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Effects and Side Effects:
Reduction in voice breaks reported by 48 hrs
 Treatment lasts an average of 3-4 months before
recurrence of symptoms
 Most common side effect is breathiness
 Other side effects include: dysphagia, prologued
voice loss, aspiration, hoarseness, pain at injection
site and stridor (with PCA injection)
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Botulinum Toxin
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No absolute contraindications
Used safely in children
Give antireflux medication to patients with
reflux
3 – 5% of patients have developed resistance to
the toxin
Resistant patients can sometimes be treated with
other toxin serotypes
Botulinum Toxin
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Injection technique for adductor SD (AdSD)
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Percutaneous injection guided by electromyographic
(EMG) signals.
Needle inserted through thyrocricoid membrane and
directed upward toward contralateral thyroarytenoid m.
 Phonation and observation of interference pattern on
EMG verifies position
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Thyroarytenoid
injection for
adductor
spasmodic
dysphonia.
Needle is
advanced
through the
cricothyroid
membrane.
Pitman MJ http://www.emedicine.com/ent/TOPIC349.HTM
Botulinum Toxin
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Alternate injection techniques for AdSD
All methods yield comparable results. Very patient and physician dependent
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Transoral laryngoscopic injections
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The transoral approach involved indirect visualization of the VF via standard
laryngoscopicprecedure. VF anesthetized through application of topical
cocaine sol’n. BTX is then injected along the superior margin of the VF
Transnasal laryngoscopic injections
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.
Transnasal technique uses a flexible nasolaryngoscope with a working channel that is
equipped with a flexible catheter needle. Topical phenylephrine and lidocaine are
sprayed transnasally, then the scope is introduced. Once in place, lidocainesol’n drip is
applied to the surface of the VF via the working channel while the pt phonates to
prevent airway penetration or aspiration. Then inject just lateral to the true VF (to
avoid damage to VF mucosa)
Transcartilaginous “point touch” injections
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Insertion of the needle through the surface of the thyroid cartilage halfway b/w thyroid
Botulinum Toxin
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Injection technique for abductor SD (AbSD)
Requires access to posterior cricoarytenoids
 Larynx is rotated manually away from injection site.
Needle passed posterior to the posterior edge of
thyroid at cricoid level into the PCA.
 Patient is asked to sniff to contract PCA and verify
correct position
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Posterior
cricoarytenoid
(PCA) injection
for abductor
spasmodic
dysphonia.
Needle is
advanced
through the
inferior
constrictor
muscle to the
PCA muscle.
Pitman MJ http://www.emedicine.com/ent/TOPIC349.HTM
Botulinum Toxin
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Blitzer et al. 1999
Reported their 12 yr experience with more than 900
patients with SD
 90% of patients with AdSD and 66.7% with AbSD
achieved a normal voice after injection
 Injection after nerve section failure showed up to
81% improvement
 Patients with combined abnormalities only had 30%
improvement
-Level of evidence (LOE): A
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Botulinum Toxin
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Advantages
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Less invasive than surgery
No permanent damage to
nerve or laryngeal
structures
Temporary nature allows
for dosage adjustments
Readily available
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Disadvantages
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Need for repeated
injections
Unpredictable
relationship between
dosage and response
Resistance to treatment
Adverse side effects
Pre-Botox Treatment
Post-Botox Treatment
Pre-Botox Treatment
Post-Botox Treatment
Neuropharmacology
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No controlled studies demonstrate effective
symptom control
Beta blockers – propranolol
Anticholinergics – trihexyphenidylHCl (Artane)
Benzodiazepines – diazepam, alprazolam
Role has been to provide relief without any
demonstrable symptom reduction
Voice Therapy
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No demonstrated effectiveness in treating SD
May help:
Rule out psychogenic disorder
 Provide support for those who do not benefit from
Botox (mild symptoms)
 Some patients use it in adjunct to Botox to prolong
symptom free period
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Traditional voice therapy approaches for ADSD employ techniques for avoiding
overpressure. Breathy voice onsets, reduced speech force, using a head focus, and
laryngeal manipulation are aimed at reducing laryngeal tension. Can also use relaxation
and respiration training to help gain insight and control of laryngeal tension during
speech.
Recurrent laryngeal nerve section
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Dedo 1976
Case series of 34 patients that had RLN section
 “All experienced symptom improvement”
 No objective measurement of outcome -LOE:C
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Dedo 1991
Retrospective review of 300 patients after RLN
section
 82% had little or no symptoms after 5-14 years
 No prospective comparative data available -LOE:B
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Recurrent laryngeal nerve section
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Aronson and DeSanto 1983
Followed 33 patients for 3 years post RLN section
 36% maintained improved voices
 Of the 64% failed voices, 48% were worse than
before surgery
 Effectiveness of unilateral RLN section for severe
ADSD decreases with time
 Limitations: small sample study -LOE:C
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Recurrent laryngeal nerve avulsion
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Netterville 1991
Retrospective review of 12 patients
 No recurrence at 1.5 years
-LOE:C
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Follow up report 1996
18 patients followed for 3-7 yrs post RLN avulsion
 16/18 patients were without spasm
 Most common side effect was breathy voice – Six
underwent medialization laryngoplasty
-LOE:C
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Therapy
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Surgical Experimental
Recurrent laryngeal nerve denervation and
reinnervation
 Type II thyroplasty
 Posterior cricoarytenoidmyoplasty with
medializationthyroplasty
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Recurrent laryngeal nerve
denervation and reinnervation
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Berke and Blumin 2006
Retrospective study analyzing satisfaction surveys
and perceptual evaluation of post operative voice
 83 of 136 patients returned surveys with 91%
satisfied with fluency of voice
 46 patients provided voice recordings for perceptual
evaluation: 26% had voice breaks, and 30%
breathiness
-LOE:B
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Recurrent laryngeal nerve
denervation and reinnervation
Limitations:
high drop out rate (61%), small sample size,
no long term prospective studies
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Advantages
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Permanent effect
Less breathiness due to
maintenance of VF tone
from ansa cervicalis
innervation
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Disadvantages
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Technical difficulty
Recurrence of symptoms
Does not prevent
unwanted reinnervations
Midline lateralization thyroplasty
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Isshiki et al. 2001
Retrospective review of 6 SD patients
 5/6 patients obtained near normal voices
 Failure attributed to difficulty in lateralization and
concurrent focal neck dystonia
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Limitations: small samples, no long term
prospective studies, no objective measures
described
-LOE:C
Atlas of Head & Neck Surgery—otolaryngology By Byron J. Bailey, Karen H. Calhoun, Norman
Modified Type II Thyroplasty
Midline lateralization thyroplasty (type 2 thyroplasty) after completion of the
procedure. “A” type using a composite graft for the closure of a tiny
perforation at or slightly above the anterior commissure. A muscle flap is used
to cover the graft. G = A composite graft.
Isshiki: Laryngoscope, Volume 111(4).April 2001.615-621
Modified Type II Thyroplasty
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B” type without using a graft. (A) The incised edges are pulled
apart to test the lateralization effect on voice. (B) The incised
edges are separated at a desired distance (usually 3–4 mm) and
fixed with silicone shims.
Isshiki: Laryngoscope, Volume 111(4).April 2001.615-621
Midline lateralization thyroplasty
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Chan 2004
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Prospective case series with 13 subjects
Used method described by Isshiki
9/13 patients failed; 2 had their surgery reversed
Reason for failure unclear
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Limitations: small sample, only used self-rating assessments and
no objective measures
-LOE:C
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Unclear why some pts deteriorate over time, especially when they had good
early results p sx. Presume that with time the VF hyperadduction is able to
overcome the initial lateralization created by the shims because the underlying
neuropathology has not been resolved.
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Continue to recommend BTX as gold standard.
Midline lateralization thyroplasty
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Advantages:
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Optimal glottal closure
can be adjusted and
readjusted
No damage of physiologic
function
Reversible
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Disadvantages:
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Technically difficult
Shim displacement
Does not relieve cause of
SD
Require careful patient
selection
Lacks reproducibility
Limitations of a retrospective study
Posterior cricoarytenoid myoplasty with
medialization thyroplasty
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Shaw 2003
Case report of 3 patients with AbSD refractory to
BTX treated with surgery and followed up to a year
post surgery
 All reported improved subjective symptoms and
showed objective reduction in phonatory breaks
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Limitations:
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Small sample and no long term prospective
outcomes
-LOE:D
Posterior cricoarytenoid myoplasty with
medialization thyroplasty
Shaw , Ann OtolRhynolLaryngol (2003) 112:303-306
Summary
Treatment
Advantage
Disadvantage
Botulinum Toxin
Type A (Botox)
Current “gold standard”; Readily Not permanent cure; risk of
available; less invasive
immunoresistance; “breathy”
voice
Type B (Myobloc)
Alternative for resistant patients
Voice Therapy
Inexpensive; No side effects; non- Not effective alone; requires
invasive; no contraindications;
high patient compliance; takes
adjunct to BTX
time to learn
RLN Section / Avulsion
“permanent” treatment
Invasive; symptom recurrence
Laryngeal adductor
denervation-reinnervation
“permanent” treatment; option
for patients resistant to BTX
Invasive; limited availability and
long term outcome data
Laryngeal framework
approach
“permanent” treatment; does not
target nerve function, reversible
Invasive; limited availability and
long term outcome data
PCA myoplasty with
medializationthyroplasty
“permanent” treatment; does not
target nerve function
Invasive; limited availability and
long term outcome data
Limited availability and use in
SD
Summary
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SD is an idiopathic d/o of the larynx. The mainstay of treatment
continues to be BTX injections into the laryngeal muscles. BTX
txt is not perfect -- there is an onset time characterized by a
breathy voice and dusphagia and an offset time characterized by
a recurrence of sxs. Occasionally pts can develop antibodies and
resistance. Some pts don’t like to receive multiple injections a
year. Because of these shortcomings alternative, more
permanent treatments have been sought. Surgery for ASDS was
initially developed in the 1970s but has been abandoned because
of poor long term results. A RLN denervation and reinervation
and laryngoplastic techniques may hold promise for long term
treatment. All current therapies for SD are directed toward the
symptoms of the d/o. There is still work toward understanding
the underlying cause so we can then possibly develop a cure to
the disease.
References
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Pearson EJ and Sapienzam CM. Historical approaches to the treatment of Adductor-Type
Spasmodic Dysphonia: Review and tutorial. NeuroRehabilitation (2003) 18:325-335
Sulica L. Contemporary management of spasmodic dysphonia. CurrOpinOtolaryngol Head Neck
Surg (2004) 12:543-548
Berke GS and Blumin JH. Spasmodic dysphonia: therapeutic options. CurrOpinOtolaryngol Head
Neck Surg (2000) 8:509-513
Grillone GA and Chan T. Laryngeal Dystonia. OtolaryngolClin N Am (2006) 39:87-100
Blitzer A, Brin MF, Stewart C. Botulinum toxin management of Spasmodic Dysphonia: 12-year
experience in more than 900 patients. Laryngoscope (1998) 108(10):1431-1441
Mehta RP et al. Long-term therapy for spasmodic dysphonia-acoustic and aerodynamic outcomes.
Arch Otolaryngol Head Neck Surg (2001) 127:393-399
Aronson AE and DeSanto LW. Adductor spastic dysphonia: three years after recurrent laryngeal
nerve resection. Laryngoscope (1983) 93:1-8
Dedo HH and Behlau MS. Reccurent laryngeal nerve section for spastic dysphonia: 5 to 14 year
preliminary results in the first 300 patients. Ann OtolRhinolLaryngol (1991) 100:274-280
Dedo HH. Recurrent laryngeal nerve section for spastic dysphonia. Ann Otol (1976) 85:451459
Weed DT et al. Long term follow up of recurrent laryngeal nerve avulsion for the treatment of
spastic dysphonia. Ann OtolRhinolLaryngol (1996) 105:592-601
References
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Netterville JL et al. Recurrent laryngeal nerve avulsion for traemtent of spasmodic dysphonia.
Ann OtolRhinolLaryngol (1991) 100:10-14
Chhetri DK, Mendelsohn AH, Blumin JH, Berke GS. Long term follow up results of selective
laryngeal adductor dennervation-reinnervation surgery for adductor spasmodic dysphonia.
Laryngoscope ( 2006) 116:635-642
Berke GS et al. Selective laryngeal adductor denervation-reinnervation: a new surgical treatment
for adductor spasmodic dysphonia. Ann OtolRhinolLaryngol (1999) 108:227- 232
Isshiki N et al. Midline lateralization thyroplasty for adductor spasmodic dysphonia. Ann
OtolRhinolLaryngol (2000) 109:187-193
Isshiki N, Yamamoto I, Fukagai S Type 2 thyroplasty for spasmodic dysphonia fixation using a
titanium bridge. ActaOtolaryngol (2004) 124:309-312
Isshiki N et al. Thyroplasty for adductor spasmodic dysphonia: further experience. Laryngoscope
(2001) 111:615-621
Shaw GY, Sechtem PR, Rideout B. Posterior cricoarytenoidmyoplsty with
medializationthyroplasty in the management of refractory abductor spasmodic dysphonia. Ann
OtolRhynolLaryngol (2003) 112:303-306
Simonyan K et al. Focal white matter changes in spasmodic dysphonia: a combined diffusion
tensor imaging and neuropathological study. Brain (2008) 131:447-459
Jurgens U. Neural pathways underlying vocal control. Neuroscience and Biobehavioral Reviews
(2002) 26:235-258
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