Vocal cord Paralysis

Vocal cord palsy & evaluation of hoarsenessDr. Vishal Sharma

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2Nerve supply of larynxMotor supply of intrinsic muscles: Cricothyroid muscle: superior laryngeal nerveAll other muscles: recurrent laryngeal nerveSensory:Above vocal cord: superior laryngeal nerve Below vocal cord: recurrent laryngeal nerve3Recurrent laryngeal nerveRight:Arises from vagus at level of right subclavian artery & hooks around itLeft:Arises from vagus in mediastinum at level of arch of aorta & loops around it4Development of arterial arches

5Final position of B/L RLN

6Superior laryngeal nerveArises from inferior ganglion of vagusDescends behind internal carotid artery at level of greater cornu of hyoid bone divides into external & internal branchesExternal motor branch: to cricothyroid muscleInternal sensory branch: pierces thyrohyoid membrane to enter larynx7

8Dual innervation of inter-arytenoid muscles

9ClassificationA. Incomplete paralysis 1. Recurrent laryngeal nerve palsy a. Left (75% ), Right (15%), B/L (10%) b. Abductor, Adductor 2. Superior laryngeal nerve palsyB. Combined paralysis / complete paralysis10Causes of laryngeal paralysisSupra-nuclearNuclear: nucleus ambiguusHigh vagal lesions: combined palsy Low vagal lesions: recurrent laryngeal nerve palsySystemic causesIdiopathic11Causes of combined paralysisIntracranial NeckTumors of posterior fossa Penetrating injuryBasal meningitis (TB) Parapharyngeal tumorsSkull base Metastatic neck nodesFractures LymphomaNasopharyngeal cancer Thyroid surgeryGlomus tumour12Etiology of recurrent laryngeal nerve palsy13Malignancy (25%): lung (>50%), thyroid, esophageal, nasopharyngeal, metastatic neck nodeSurgical trauma (20%): during surgeries of lung, heart, thyroid, esophagus, mediastinum Inflammatory (13%): tuberculosis, syphilisIdiopathic (13%): viral neuritisNon-surgical trauma (11%): accidental neck trauma, left atrial enlargement (Ortner), aortic aneurysmNeurological (7%): CVA, head injury, Parkinsonism, multiple sclerosis, alcoholic / diabetic neuropathyOthers (11%): rheumatoid arthritis, haemolytic anemia14Causes of left RLN palsy (75%)Neck Accidental trauma Thyroid disease Thyroid surgery Ca esophagus Lymphadenopathy

Mediastinum Bronchogenic ca Ca esophagus Aortic aneurysm Lymphadenopathy Enlarged left atrium Intra-thoracic surgery15Causes of right RLN palsy (15%)Neck traumaThyroid diseaseThyroid surgeryCa cervical esophagusCervical lymphadenopathy Aneurysm of subclavian arteryCa apex right lungTB of cervical pleura 16Causes of B/L RLN palsy (10%)Thyroid surgeryCa thyroidCancer cervical esophagusCervical lymphadenopathy17Congenital vocal cord paralysisUnilateral: birth trauma, congenital anomaly of great vessel or heartBilateral: Hydrocephalus Meningocoele Arnold-Chiari malformation Cerebral agenesis Intra-cerebral hemorrhage Nucleus ambiguus agenesis18Thyroid surgeryJolls sterno-thyro-laryngeal triangle for S.L.N.:Lateral = superior thyroid vessels & upper thyroid pole; superior = attachment of strap muscles to thyroid cartilage; medially = midlineBeahrs triangle for recurrent laryngeal nerve:Lateral = common carotid artery; superior = inferior thyroid artery; medial = tracheo-esophageal groove + recurrent laryngeal nerve19Jolls triangle for SLN

20Beahrs triangle for RLN

21Why right RLN commonly damaged in thyroid surgery?Right recurrent laryngeal nerve more superficialRight nerves enters thyroid at 450 angle but left lies in tracheo-esophageal grooveRight nerve mostly passes superior to or b/w branches of inferior thyroid artery; left nerve mostly passes deep to inferior thyroid artery22Position of vocal cordDistance from centreHealthyDiseasedMedianMidlinePhonationRLN paralysisParamedian1.5 mmStrong whisperRLN paralysisIntermediate(Cadaveric)3.5 mm(neutral position)Paralysis of both RLN & SLNGentle abduction7 mmQuiet respirationParalysis of adductorsFull abduction9.5 mm Deep inspiration--

23Position of vocal cords

24Semons LawRosenbach (1880) & Semon (1881)In all progressive organic lesions, abductor fibres of recurrent laryngeal nerve, which are phylogenetically newer, are more susceptible and thus first to be paralyzed compared to adductor fibres.251st stage: only abductor fibres damaged; vocal folds approximate in midline; adduction still possible (paramedian position)2nd stage: contracture of adductors; vocal folds immobilized in median position3rd stage: adductors become paralyzed; vocal fold assumes cadaveric position26Why abductors affected first ?Nerve fibres supplying abductors are in periphery of recurrent laryngeal nerveMuscle bulk for the abductors is less, more susceptiblePhylogenetically, larynxs main function is protection, so adductor functions are maintained27Wagner & Grossman TheoryIn isolated paralysis of recurrent laryngeal nerve, cricothyroid muscle (which receives innervation from superior laryngeal nerve) keeps vocal cord in paramedian position due to adductor functionIn superior laryngeal nerve palsy, cord lies in intermediate (cadaveric) position28 Final position of paralyses vocal cord is not static & is decided by:Degree of paralyzed muscle atrophy & fibrosisDegree of re-innervation following injuryExtent of synkinesis (mass movement) of all intrinsic musclesFibrosis & ankylosis of crico-arytenoid jointModern theory29Retrograde atrophy of vagus nerve occurs up to nucleus ambiguusStretching of RLN by enlarged intra-thoracic lesions pulls vagus nerve down from skull base, injuring superior laryngeal nerveIntermediate position of vocal cords in RLN palsy ?30Vocal cord paralysisCricoarytenoid joint fixationFloppy, vocal cords with bowingArytenoids falls antero-medially Vocal cord at a higher levelTilting of larynx paralysed sideFlickering of cord on phonationShallow pyriform fossaFixed in specific positionArytenoids can be movedAbsentIn positionSame levelAbsentAbsentNormal Any position Arytenoids fixed31Clinical Features32Lesion above pharyngeal branchInability to elevate soft palate, nasal intonation, nasal regurgitation & nasal emissions Gag reflex reduced or absent due to palsy of internal branch of superior laryngeal nerve Hoarseness due to palsy of intrinsic muscles of larynx 33Asymptomatic (1/3rd unilateral paralysis)Faint whisperFunctional adductor paralysisForced whisperOrganic adductor paralysisVoice tires with useUnilateral abductor paralysisStridor & aspiration Bilateral abductor paralysis34U/L S.L.N. palsyB/L S.L.N. palsyDisability in professional voice user onlyVoice weak, breathy, inability to raise pitchAnterior commissural tilt to healthy sideShort & flabby vocal foldFlapping cord during respirationProfessional voice compromisedVoice weak, breathy, inability to raise pitchAbsence of anterior commissural tilt Cough & choking due to aspiration35U/L combined palsyB/L combined palsyCord in cadaveric position hoarsenessGlottic incompetence ineffective cough Partial anesthesia of larynx aspirationB/L cords in cadaveric position aphoniaGlottic incompetence ineffective coughTotal anesthesia of larynx aspiration + bronchopneumonia36Specific Investigations37Voice assessment1. Magnetic tape recording: for self assessment2. Performance assessment by examiner: maximum phonation time & range of speech frequencies3. Phonetogram: plot of pitch vs. intensity of voice4. Aerodynamic analysis: phonatory airflow rate, subglottic pressure & laryngeal resistance 38Phonetogram

39Aerodynamic analysis

405. Fouriers Spectral analysis (Spectrogram)Fundamental frequency: lowest speech frequencyShimmer: average cycle to cycle difference in amplitude of soundJitter: average cycle to cycle difference in duration of glottal cycleIn hoarseness there is increased shimmers & jitters41Spectrogram

42Shimmer & Jitter

43Analysis of cord movement1. Rigid 700 video-telescopy LA2. Fibreoptic video-laryngoscopy 3. Stroboscopy: Intermittent flash light focussed on vocal cords during phonation. Frequency of light made 2 msec slower to cord frequency. Produces slow motion movement of vocal cords for better analysis of cord movement 44Video-stroboscopy

454. Electro-glottography: 2 electrodes placed on both sides of thyroid cartilage & current passed b/w them. Recorded waveform shows impedance across larynx & is highest during contact b/w vocal cords. Records closing phase of glottal cycle. 5. Photo-glottography: fibreoptic light source passes light via glottis & is received by photo-sensor on neck skin. Light received glottic chink. Records opening phase of glottal cycle. 46Electroglottography

47Photoglottography

48RadiologicalSubmento-vertical skull base viewX-ray neck AP & lateral viewChest X-ray PA viewBarium swallow AP & lateral oblique viewHigh resolution CT scan with contrast from skull base to mid thorax: gold standardM.R.I.: ideal for skull base lesionsThyroid scan49Endoscopy1. Rigid 700 Telescopy LA2. Fibreoptic Laryngoscopy LA3. Pan-endoscopy GA (for metastatic node): a. Nasopharyngoscopy b. Micro-laryngoscopy: probe test on arytenoids c. Bronchoscopy & bronchial washings d. Hypopharyngoscopy e. Oesophagoscopy50Fibre-optic laryngoscopyparalyzed vocal fold is foreshortened, lateralized & flaccid

51B/L abductor palsy

InspirationExpiration52Biopsy for suspected malignancy1. F.N.A.B. from enlarged lymph nodes2. Punch biopsy from visible growth3. Blind biopsy from (if metastatic node present): Fossa of RosenmullerBase of tonguePyriform fossaLaryngeal ventriclesBronchial carina53Respiratory function test1. Conventional spirometry2. Flow-Volume Loop analysisVariable extra-thoracic obstruction: ed inspiratory flowIntra-thoracic obstruction: ed expiratory flowFixed obstruction: ed inspiratory + expiratory flow54Flow volume loop analysis

55Other investigationsBlood: ESR, serology for syphilisElectromyography of intrinsic laryngeal muscles: a. Normal: Joint fixation, post - scarring b. Fibrillation: Denervation (bad prognosis) c. Polyphasic: Synkinesis, Re-innervation (good prognosis)56Electromyography

57Treatment for phonatory gap in U/L abductor or adductor palsy58Speech therapy: for 2-12 months (usual treatment)Vocal cord injection: with Teflon / fat / collagenMedialization thyroplasty (Isshiki type I)Arytenoid adduction: for posterior approximationArytenoidopexy: medial rotation + fixation Laryngeal re-innervationCombination of above59Indications for immediate surgical interventionElectromyography shows fibrillation (complete loss of function with no signs of recovery)Vocal cord palsy due to nerve entrapment in thyroid / bronchial malignancy where recovery is not expected60Per-oral Teflon injectionKleinsassers microlaryngoscope introduced Brunings syringe loaded with Teflon pasteNeedle pushed lateral to thyroarytenoid muscleFirst injection at postero-lateral angle of middle third of vocal cord, 2.5 mm lateral to cord marginSecond injection (0.2 ml) made at antero-lateral angle till both cords approximate in phonationI.V. Dexamethasone given for 24 hours61Per-oral Teflon injection

62Vocal fold Teflon injection

63Percutaneous Teflon injectionNeedle introduced in midline through crico-thyroid membrane angled 300 - 450 upward & laterally into vocal cord Direct lateral penetration of larynx through thyroid ala is alternate route of injectionVocal cord entered under endoscopic control64Percutaneous Teflon injection

65Midline & lateral routes

66Vocal fold fat injection

67Vocal fold collagen injection

68Isshikis ThyroplastyType 1 (medial displacement)Type 2 (lateral displacement)Type 3 (shortening or relaxation)Type 4 (elongation of tensioning)Thyroplasty is reversible, does not invade vocal folds nor alters their mass or stiffness unlike vocal fold injection69Thyroplasty type I

70Thyroplasty type I

71Thyroplasty type IHorizontal skin incision made over mid-point of thyroid cartilage lamina (from a point 2 cm lateral to midline on opposite side to posterior margin of thyroid cartilage on affected side)Subplatysmal flaps elevated & strap muscles retracted laterally to expose thyroid cartilageWindow made in thyroid lamina with scalpel or 1 mm cutting burr, as per Koufmans formula72Windows superior border lies at level with vocal cords (midpoint b/w thyroid notch & inferior margin of thyroid cartilage) & its anterior border situated 8 mm posterior to midlineCartilage removal started postero-inferiorlyInner perichondrium elevated off thyroid cartilage & silastic prosthesis insertedPatient asked to phonate while moving silastic prosthesis into its optimal position under flexible laryngoscopy guidance73Type I thyroplasty

74Koufmans formula

Window height (mm) = thyroid alar height (mm) 4 ------------------------------------- 4 Window width (mm) = thyroid alar height (mm) 4 ------------------------------------ 2Average = 12 X 6 mm (male); 10 X 5 mm (female)75Insertion of prosthesis

76Insertion of silastic prosthesis

77Silastic implant

78Arytenoid adductionPortion of posterior thyroid cartilage margin cut to expose muscular process of arytenoidTwo 4-0 Prolene sutures passed through muscular process & through thyroid cartilage Sutures pulled parallel to lateral cricoarytenoidAfter optimal medialization of vocal fold, sutures tied on external aspect of thyroid lamina79Arytenoid adduction

80Arytenoid adduction

81Laryngeal re-innervationNeuromuscular pedicle of superior belly of omohyoid (or sternohyoid) + ansa hypoglossi nerve transferred into thyro-arytenoideus for vocal fold medialization; or posterior crico-arytenoideus for lateralization (Tucker)Neural anastomosis of ansa hypoglossi nerve directly to recurrent laryngeal nerve (Crumley)82Neuromuscular pedicle

83Neuromuscular pedicle

84Neuromuscular pedicle

85Ansa-R.L.N. anastomosis

86Combination surgeriesNeuromuscular pedicle re-innervation + Thyroplasty type 1Thyroplasty type 1 + arytenoid adduction Arytenoid adduction has advantage of posterior glottic approximation unlike thyroplasty87Treatment of stridor in B/L abductor paralysis88Tracheostomy: temporary / permanent in acute stridorVocal cord lateralization: endoscopic, external (King)Vocal cordectomy: external, endoscopicEndoscopic vocal cordotomy: knife, cautery, laserArytenoidectomy: endoscopic, external (Woodman) Lateralization thyroplasty (Isshiki type II)Laryngeal re-innervation: ansa hypoglossi-omohyoid pedicle transfer into posterior crico-arytenoideus89Vocal cord lateralization (laterofixation / cordopexy)

90Vocal cord lateralizationThyroid cartilage exposed via horizontal incision16-gauge IV cannula inserted through thyroid cartilage 4 mm anterior & 2 mm below mid-point of oblique line, into laryngeal lumen, just above tip of vocal process, under M.L.S. guidance Another 16-gauge IV cannula inserted 5 mm below 1st cannula, just below tip of vocal process91Vocal cord lateralization1-0 Prolene suture threaded through inferior cannula into laryngeal lumenSuture thread brought out with forceps into laryngeal lumen & inserted into superior cannulaExternal traction put on both suture ends to pull vocal cord laterally to give a 5 mm airwayThreads tied over thyroid lamina 8 times 92Cordectomy

93Cordectomy + lateralization

94Posterior cordotomy

95Arytenoidectomy

96Cordotomy + arytenoidectomy

97Thyroplasty type II (lateralization)

98Treatment for bilateral adductor paralysis causing chronic aspiration99Endolaryngeal stenting (solid & vented)Epiglottic flap closureEpiglottopexy to posterior pharyngeal wallEpiglottic tube laryngoplasty Glottic closureSub-perichondrial cricoidectomyTracheo-esophageal diversionLaryngo-tracheal separationNarrow field laryngectomy 100Endolaryngeal stent

101Epiglottic flap closure

102Epiglottopexy

103Epiglottic tube laryngoplasty

104Glottic closure

105Subperichondrial cricoidectomy

106Tracheo-esophageal diversion

Proximal trachea anastomosed with esophagusDistal trachea opens into permanent tracheostomy 107Laryngo-tracheal separation

Proximal trachea closedDistal trachea opens into permanent tracheostomy108Narrow field laryngectomy

109Other procedures for aspirationDouble cuff tracheostomyLaryngeal suspensionFeeding GastrostomyFeeding JejunostomyVocal cord injectionMedialization thyroplastyLaryngeal re-innervationTympanic / Chorda tympani neurectomy110Laryngeal suspension

111Other vocal cord surgeries112Thyroplasty type III (shortening)

Used for mutational falsetto113Thyroplasty type IV (elongation)

Used for raising vocal pitch & ing vocal tension114Evaluation of Hoarseness (dysphonia)115Causes of Hoarseness116Mechanism of hoarsenessLoss of approximation of vocal cords: in paralysis, fixation or intervening tumor / lesionsAlteration of size of vocal cord: ed in edema, tumor; ed in partial surgical excision, fibrosis Alteration of stiffness of vocal cord: ed in spasmodic dysphonia, fibrosis; ed in paralysisImproper vibration of vocal cord: hyperemia, vocal nodule, vocal polyp 11710 organic dysphonia20 organic dysphonia1. Congenital *1. Laryngitis *2. Laryngeal tumor *2. Vocal nodule3. Vocal cord palsy3. Vocal polyp4. Spasmodic 4. Reinkes edema5. Muscular *Functional dysphonia6. Neurological *1. Psychogenic7. Endocrine *2. Habitual8. Senile3. Puberphonia9. Fixation by arthritis4. Ventricular * 10. Traumatic *5. Malingering118Congenital: laryngomalacia, laryngocoele, haemangioma, webLaryngeal tumor: papilloma, malignancyMuscular: myasthenia gravisNeurological: Parkinsonism, Multiple sclerosis, cerebro-vascular accident, bulbar palsyEndocrine: hypothyroidism, inter-sex, pregnancy Traumatic: accidental, foreign body, intubationLaryngitis: bacterial, viral, TB, allergic, GERD Ventricular: dysphonia plica ventricularis1191. Duration: > 3 weeks in pt > 40 years is laryngeal malignancy until proven otherwise2. Progression: due to mass effect or malignancy3. Voice quality: a. Forced whisper: Organic adductor paralysis b. Faint whisper: Functional adductor paralysis c. Tires with use: U/L abductor paralysis, myastheniaHistory taking1204. Associated symptoms: a. Stridor: B/L abductor paralysis b. Aspiration: B/L adductor paralysis c. Dysphagia + exertion dyspnea: Ortners syndrome d. Hemoptysis: lung malignancy, tuberculosis e. Nasal regurgitation & intonation: high vagal lesion5. Past history: a. Trauma: accidental, foreign body, intubation b. Surgery: thyroid, intra-thoracic c. Viral upper respiratory tract infection, smoking121Physical ExaminationListening to patients voice: for hoarseness Indirect laryngoscopy: laryngeal lesionsOtoscopy: rule out glomus tumorNeck: lymph node enlargement, thyroid disease Chest: lung malignancy, tuberculosisCardiovascular: mitral stenosis Neurological: Parkinsonism, multiple sclerosis 122Manual compression testImprovement in voice = do thyroplasty (anterior medialization procedure). No improvement in voice = do arytenoid adduction (posterior medialization procedure)

123Routine investigationsFibre-optic laryngoscopyMicrolaryngoscopy: crico-arytenoid joint mobilityCT scan skull base to diaphragm: bestX-ray chest: for hemoptysis Ba swallow: for dysphagiaThyroid scan: for thyroid enlargementPanendoscopy: in presence of hard neck node124Thank You

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