Vocal Cord Vocal Cord DysfunctionDysfunction

Joan C. GrilloJoan C. Grillo

OutlineOutline Definition & Other LabelsDefinition & Other Labels PresentationPresentation Patient profilePatient profile

DemographicsDemographics ComorbiditiesComorbidities

Potential EtiologiesPotential Etiologies Differential DiagnosisDifferential Diagnosis TreatmentTreatment

TeamTeam Treatment methodsTreatment methods

ConclusionConclusion

DefinitionDefinition

Vocal Cord DysfunctionVocal Cord Dysfunction (VCD) is a (VCD) is a disorder of the upper airway in which disorder of the upper airway in which the vocal folds (and sometimes the the vocal folds (and sometimes the ventricular folds) ventricular folds) adductadduct during during inspiration, exhalation, or both. This inspiration, exhalation, or both. This often results in inspiratory stridor often results in inspiratory stridor and respiratory distress. In the and respiratory distress. In the literature, it is most often described literature, it is most often described as adduction upon as adduction upon inspirationinspiration..

DefinitionDefinition

This is a picture of the abducted position of the vocal folds. This is what they should look like during respiration.

This is a picture of the adducted position of the vocal folds. This is what the vocal folds of patients with VCD do when they are trying to breathe.

Other LabelsOther Labels Paradoxical Vocal Fold Motion/Movement (PVFM)Paradoxical Vocal Fold Motion/Movement (PVFM) Paradoxical Vocal Cord Motion/Movement (PVCM)Paradoxical Vocal Cord Motion/Movement (PVCM) Paradoxical Vocal Fold Dysfunction (PVFD)Paradoxical Vocal Fold Dysfunction (PVFD) Paradoxical Vocal Cord Dysfunction (PVCD)Paradoxical Vocal Cord Dysfunction (PVCD) Irritable Larynx SyndromeIrritable Larynx Syndrome Munchausen’s stridor (original name, first reported in 1974)Munchausen’s stridor (original name, first reported in 1974) Factitious asthmaFactitious asthma Hysterical or psychogenic asthmaHysterical or psychogenic asthma Steroid-resistant asthmaSteroid-resistant asthma Episodic paroxysmal laryngospasmEpisodic paroxysmal laryngospasm Functional upper airway obstructionFunctional upper airway obstruction Functional laryngeal stridorFunctional laryngeal stridor Psychogenic stridorPsychogenic stridor Episodic Laryngeal dyskinesiaEpisodic Laryngeal dyskinesia

This long list of labels helps illustrate the point that VCD is actually a This long list of labels helps illustrate the point that VCD is actually a family of syndromesfamily of syndromes

PresentationPresentation

PresentationPresentation Patients most often present with symptoms such Patients most often present with symptoms such

asas Stridor (particularly on inhalation)Stridor (particularly on inhalation) WheezingWheezing Choking sensationChoking sensation Acute episodic dyspnea (shortness of breath)Acute episodic dyspnea (shortness of breath) AphoniaAphonia DysphoniaDysphonia DysphagiaDysphagia Chronic cough (often triggered by exposure to irritants Chronic cough (often triggered by exposure to irritants

or on exertion)or on exertion) Tightness in the throatTightness in the throat Difficulty “getting air in”Difficulty “getting air in” Globus sensationGlobus sensation

PresentationPresentation Patients often report that certain things Patients often report that certain things

trigger episodes, such astrigger episodes, such as Cigarette smokeCigarette smoke Cold airCold air ExerciseExercise PerfumePerfume CleanersCleaners Chemical odorsChemical odors StressStress

In children, the airway obstruction In children, the airway obstruction experienced during an episode can trigger experienced during an episode can trigger a panic attacka panic attack

Patient ProfilePatient Profile

Patient ProfilePatient Profile

Demographic characteristicsDemographic characteristics Most often occurs in femalesMost often occurs in females Children and teens with VCD tend to be Children and teens with VCD tend to be

high achievers and athleteshigh achievers and athletes Many have high levels of stress and/or Many have high levels of stress and/or

anxietyanxiety Different studies describe very different Different studies describe very different

profilesprofiles Incidence and prevalence data are sparseIncidence and prevalence data are sparse

Patient ProfilePatient Profile

Common comorbiditiesCommon comorbidities GERGER AsthmaAsthma AnxietyAnxiety Laryngeal muscle tension and Laryngeal muscle tension and

hyperfunctionhyperfunction

Potential Potential EtiologiesEtiologies

Potential EtiologiesPotential Etiologies Maschka et al wrote an article in 1997 which Maschka et al wrote an article in 1997 which

classified types of PVCM based on what they classified types of PVCM based on what they proposed to be the different etiologies.proposed to be the different etiologies.

TABLE II. Classification Scheme for Paradoxical Vocal Cord Motion. From:   Maschka: Laryngoscope, Volume 107(11).November 1997.1429-1435

Potential EtiologiesPotential Etiologies

TABLE I. Characteristic Features. From:   Maschka: Laryngoscope, Volume 107(11).November 1997.1429-1435

Below is a table of the characteristic Below is a table of the characteristic features of each type, according to this features of each type, according to this paper.paper.

SLPs most often encounter the last four SLPs most often encounter the last four types.types.

Potential EtiologiesPotential Etiologies

The organic causes described in this The organic causes described in this paper are, in general, seen less often paper are, in general, seen less often than the nonorganic causes.than the nonorganic causes.

GER occurs very frequently in GER occurs very frequently in patients with VCD, but at this time the patients with VCD, but at this time the relationship between GER and VCD is relationship between GER and VCD is only correlation. Causation has not only correlation. Causation has not been established. Many theorize that been established. Many theorize that GER might trigger VCD episodes.GER might trigger VCD episodes.

Potential EtiologiesPotential Etiologies

In 1982, Kellman & Leopold wrote a In 1982, Kellman & Leopold wrote a paper on three cases of PVCM they paper on three cases of PVCM they had seen in the hospital.had seen in the hospital.

Although they considered all three Although they considered all three cases to be functional in nature, all cases to be functional in nature, all three patients continued to have true three patients continued to have true vocal fold adduction on inspiration vocal fold adduction on inspiration during asymptomatic periodsduring asymptomatic periods when when examined via indirect laryngoscopy.examined via indirect laryngoscopy.

Potential EtiologiesPotential Etiologies In 1999, Treole et al did a study in which they examined 50 In 1999, Treole et al did a study in which they examined 50

adult patients diagnosed with PVFD and 54 normal adult adult patients diagnosed with PVFD and 54 normal adult controls.controls.

All 50 of the patients with PVFD had some degree of abnormal All 50 of the patients with PVFD had some degree of abnormal adduction of the true vocal folds during respiration adduction of the true vocal folds during respiration even even when asymptomaticwhen asymptomatic..

Stroboscopy during asymptomatic periods revealed Stroboscopy during asymptomatic periods revealed abnormalities such as decreased amplitude and mucosal abnormalities such as decreased amplitude and mucosal wave, unstable zero phase, and phase asymmetry for the wave, unstable zero phase, and phase asymmetry for the PVFD group significantly more often than the control group.PVFD group significantly more often than the control group.

These results and the findings of the previous study indicate These results and the findings of the previous study indicate that, at least for some patients, “…PVFD is not episodic but that, at least for some patients, “…PVFD is not episodic but exists as a continuum of laryngeal instability that may, due to exists as a continuum of laryngeal instability that may, due to various precipitating factors, be exacerbated to breathing various precipitating factors, be exacerbated to breathing attacks.” (p. 143)attacks.” (p. 143)

Potential EtiologiesPotential Etiologies Morrison et al describe, in their 1999 paper, a unifying hypothesis to account for a Morrison et al describe, in their 1999 paper, a unifying hypothesis to account for a

variety of symptoms in what they call Irritable Larynx Syndrome (ILS).variety of symptoms in what they call Irritable Larynx Syndrome (ILS).

The theory is that neural plastic changes occur in brainstem laryngeal control The theory is that neural plastic changes occur in brainstem laryngeal control networks – similar to those that occur with chronic pain – which cause the larynx networks – similar to those that occur with chronic pain – which cause the larynx to be in a constant spasm-ready state of hyper-excitability for people with ILS.to be in a constant spasm-ready state of hyper-excitability for people with ILS.

Inclusion criteria for ILS are Inclusion criteria for ILS are 1.1. Symptoms attributable to laryngeal tensionSymptoms attributable to laryngeal tension

Dysphonia and/or laryngospasmDysphonia and/or laryngospasm With or without globus and/or chronic coughWith or without globus and/or chronic cough

2.2. Visible and palpable evidence of tensionVisible and palpable evidence of tension Laryngoscopic lateral and AP contractionLaryngoscopic lateral and AP contraction Palpation: suprahyoid, thyrohyoid, and cricothyroid, pharynxPalpation: suprahyoid, thyrohyoid, and cricothyroid, pharynx

3.3. Presence of a sensory triggerPresence of a sensory trigger Airborne substance, esophageal irritant, odorAirborne substance, esophageal irritant, odor

The diagnosis of ILS is excluded if there is apparent organic laryngeal pathology, The diagnosis of ILS is excluded if there is apparent organic laryngeal pathology, an identifiable neurological disease, or identifiable psychiatric diagnosis.an identifiable neurological disease, or identifiable psychiatric diagnosis.

The ILS theory explains some subgroups of patients with VCD very well, although The ILS theory explains some subgroups of patients with VCD very well, although the requirement of overt laryngeal muscle tension excludes much of the VCD the requirement of overt laryngeal muscle tension excludes much of the VCD population.population.

This theory parallels Treole’s idea that some sort of change has occurred in these This theory parallels Treole’s idea that some sort of change has occurred in these certain individuals that causes the larynx to be hypersensitive to certain triggers.certain individuals that causes the larynx to be hypersensitive to certain triggers.Morrison et al., (1999) p.

448

Differential Differential DiagnosisDiagnosis

Differential DiagnosisDifferential Diagnosis Because of the presentation, VCD is often misdiagnosed as asthma or Because of the presentation, VCD is often misdiagnosed as asthma or

multiple chemical sensitivity, despite the fact that VCD is not responsive multiple chemical sensitivity, despite the fact that VCD is not responsive to asthma treatments. to asthma treatments. It is important to remember that VCD does It is important to remember that VCD does occur comorbidly with asthma in some patients, and this can occur comorbidly with asthma in some patients, and this can complicate diagnosis.complicate diagnosis.

This misdiagnosis of asthma often leads to unsuccessful treatment of This misdiagnosis of asthma often leads to unsuccessful treatment of asthma with steroids and other medications which are ineffective and can asthma with steroids and other medications which are ineffective and can have negative side effects.have negative side effects.

In extreme cases, patients have been intubated or given tracheostomies In extreme cases, patients have been intubated or given tracheostomies due to acute respiratory distress. Many believe that these measures may due to acute respiratory distress. Many believe that these measures may be avoided if proper diagnosis of VCD is made.be avoided if proper diagnosis of VCD is made.

VCD can also be misdiagnosed as true laryngospasm – the difference VCD can also be misdiagnosed as true laryngospasm – the difference being that in true laryngospasm, the vocal folds do not abduct.being that in true laryngospasm, the vocal folds do not abduct.

VCD was once considered to be purely psychogenic, but a body of VCD was once considered to be purely psychogenic, but a body of literature is developing that supports the theory that in some patients, literature is developing that supports the theory that in some patients, there is an actual laryngeal hypersensitivity, incoordination, or dystonia there is an actual laryngeal hypersensitivity, incoordination, or dystonia that exists all the time, and worsens with acute attacks.that exists all the time, and worsens with acute attacks.

Differential DiagnosisDifferential Diagnosis Definitive diagnosis is made by observing the Definitive diagnosis is made by observing the

trademark symptom of true vocal fold adduction trademark symptom of true vocal fold adduction during inhalation. Many times a diamond-shaped during inhalation. Many times a diamond-shaped posterior glottic chink is also noted, but is not posterior glottic chink is also noted, but is not required for diagnosis.required for diagnosis.

Many patients, when between attacks, present Many patients, when between attacks, present normally when examined via videolaryngoscopy.normally when examined via videolaryngoscopy.

For these patients, the clinician must elicit an attack For these patients, the clinician must elicit an attack and view the trademark symptom in order to and view the trademark symptom in order to definitively diagnose VCD.definitively diagnose VCD.

There are some organic etiologies (such as There are some organic etiologies (such as brainstem compression) that can only be diagnosed brainstem compression) that can only be diagnosed by radiographic imaging.by radiographic imaging.

Differential DiagnosisDifferential Diagnosis

Differentiating VCD from AsthmaDifferentiating VCD from Asthma Pulmonary flow-volume loopPulmonary flow-volume loop

Husain & Habib, (2008)

Airway Airway obstruction obstruction occurring occurring aboveabove the sternal notch the sternal notch (as with VCD) is (as with VCD) is indicated by what indicated by what is called a is called a “flattened” “flattened” inspiratory limb inspiratory limb as seen here in as seen here in Figure 6.Figure 6.

Differential DiagnosisDifferential Diagnosis Mathers-Schmidt (2001) and Sandage & Mathers-Schmidt (2001) and Sandage &

Zelazny (2004) provide tables listing Zelazny (2004) provide tables listing differential diagnostic features of PVFM and differential diagnostic features of PVFM and asthmaasthma

Mathers-Schmidt (2001) p. 116

Sanders & Zelazny (2004) p. 355

Differential DiagnosisDifferential Diagnosis Koufman & Block (2008) provide a table outlining Koufman & Block (2008) provide a table outlining

differential diagnostic features of PVFM and laryngospasm differential diagnostic features of PVFM and laryngospasm (LS).(LS).

This same article provides a table with differentiating This same article provides a table with differentiating features of the causes of PVFM.features of the causes of PVFM.

p. 328, 330

Differential DiagnosisDifferential Diagnosis

Finally, Koufman & Block (2008) Finally, Koufman & Block (2008) provide a chart outlining the various provide a chart outlining the various causes of stridorcauses of stridor

p. 332

TreatmentTreatment

TreatmentTreatment

To adequately diagnose and treat To adequately diagnose and treat VCD requires a team approach. VCD requires a team approach. Team members includeTeam members include Primary care physicianPrimary care physician PulmonologistPulmonologist OtolaryngologistOtolaryngologist Speech-Language PathologistSpeech-Language Pathologist Possibly psychiatrist/psychologistPossibly psychiatrist/psychologist

TreatmentTreatment Treatment methods SLPs can employTreatment methods SLPs can employ

Patient educationPatient education Explanation and reassuranceExplanation and reassurance Biofeedback using videolaryngoscopyBiofeedback using videolaryngoscopy

Speech therapySpeech therapy Respiratory re-educationRespiratory re-education

Sniff-hiss breathing techniqueSniff-hiss breathing technique Concentration on rhythmic, active, and supported Concentration on rhythmic, active, and supported

expiration (rather than inspiratory focus) during attacksexpiration (rather than inspiratory focus) during attacks Upper body relaxation including laryngeal musculatureUpper body relaxation including laryngeal musculature Easy onsetEasy onset Resonant voice techniquesResonant voice techniques

Supportive counselingSupportive counseling

Altman et al., (2002)

TreatmentTreatment Treatment methods other team members can Treatment methods other team members can

employemploy Medical management of possible triggersMedical management of possible triggers

Treatment for GERTreatment for GER Psychiatric treatment, particularly for anxiety or to Psychiatric treatment, particularly for anxiety or to

address conversion disorderaddress conversion disorder Anti-allergy therapyAnti-allergy therapy

Botox injections in the thyroarytenoid muscles Botox injections in the thyroarytenoid muscles Oxygen or heliox (80% helium/20% oxygen)Oxygen or heliox (80% helium/20% oxygen) Constant Positive Airway Pressure (CPAP)Constant Positive Airway Pressure (CPAP) Discontinuation of unnecessary bronchodilators and Discontinuation of unnecessary bronchodilators and

steroidssteroids Surgery to correct organic etiologies such as Surgery to correct organic etiologies such as

brainstem compressionbrainstem compression In recalcitrant cases, tracheostomyIn recalcitrant cases, tracheostomy

Altman et al., (2002)

ConclusionConclusion VCD is a family of syndromesVCD is a family of syndromes

In order to diagnose and treat VCD effectively, a thorough history must be taken, In order to diagnose and treat VCD effectively, a thorough history must be taken, includingincluding

Psycho-emotional issuesPsycho-emotional issues Phonotraumatic behaviorsPhonotraumatic behaviors Medical factorsMedical factors Muscle tension patternsMuscle tension patterns Triggers and exacerbating stimuliTriggers and exacerbating stimuli Phonatory and respiratory involvementPhonatory and respiratory involvement

Differential diagnosis should be made by a team of medical professionals (including Differential diagnosis should be made by a team of medical professionals (including SLPs)SLPs)

All relevant variables contributing to the condition should be examined and addressedAll relevant variables contributing to the condition should be examined and addressed

Treatment plans should be individually tailored to meet the specific needs of each Treatment plans should be individually tailored to meet the specific needs of each patientpatient

The benefits of simply identifying the disorder and reassuring a patient that it can be The benefits of simply identifying the disorder and reassuring a patient that it can be treated should never be underestimatedtreated should never be underestimated

Although a psychogenic component may play a part in the onset of acute episodes of Although a psychogenic component may play a part in the onset of acute episodes of VCD, that does not rule out an underlying organic etiologyVCD, that does not rule out an underlying organic etiology

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