1. LARYNGEAL
PARALYSIS
DEPT OF OTORHINOLARYNGOLOGY
JJM M C
DAVANAGERE

2. NERVE SUPPLY OF
LARYNX
• Superior laryngeal nerve-internal
branch is sensory supplies larynx
above the level of vocal cords and
external branch supplies cricothyroid
muscle.
• Recurrent laryngeal nerve-Motor
branch supplies all muscles of larynx
except the cricothyroid and sensory
branch supplies subglottis

4. RECURRENT LARYNGEAL
NERVE (RLN)
• Right RLN arises from vagus, hooks
around subclavian artery and ascends
upwards in tracheo-oesophageal groove
• Left RLN arises from vagus, hooks
around arch of aorta and ascends
upwards in tracheo-oesophageal groove
• Left RLN has longer course thus its prone
for injury

5. SUPERIOR LARYNGEAL
NERVE (SLN)
• Arises in inferior ganglion of
vagus, descends behind internal
carotid artery and at the level of
greater cornua of hyoid it divides
into internal and external branches

7. CLASSIFICATION OF
LARYNGEAL PARALYSIS
• May be unilateral or bilateral and
may involve
1. Recurrent laryngeal nerve
2. Superior laryngeal nerve
3. Both recurrent and superior
laryngeal nerve (combined or
complete paralysis)

8. CAUSES OF LARYNGEAL
PARALYSIS
• Supranuclear: Rare
• Nuclear: involvement of nucleus
ambiguus in medulla, usually associated
with other lower cranial nerve paralysis
• High vagal lesions: may be involved at
the level of jugular foramen or
parapharyngeal space
• Low vagal or RLN
• Systemic causes: diabetes mellitus,
diphtheria, typhoid, lead poisoning
• Idiopathic: in about 30% of cases

10. RLN PARALYSIS
• Unilateral
Results in ipsilateral paralysis of
all intrinsic muscles except the
cricothyroid
Vocal cord assumes a median or
paramedian position and does not
move laterally on deep inspiration

13. RLN PARALYSIS
-SEMON’S LAW
• This law explains median or
paramedian position of the vocal
cords
• It states that ‘In all progressive
lesions of RLN, abductor fibres of the
nerve, which are phylogenetically
newer, are more susceptible and thus
first to be paralysed compared to
adductor fibres’
fibres

14. RLN PARALYSIS- WEGNER
AND GROSSMAN HYPOTHESIS
• It states that cricothyroid muscle
which receives innervation from
superior laryngeal nerve keeps the
cord in paramedian position due to
adductor function

16. RLN PARALYSIS
CLINICAL FEATURES
• May be undetected as 1/3rd of patients
remain asymptomatic
• Some patients may complain of
change of voice
• Voice gradually improves due to
compensation by healthy cord which
crosses the midline to meet paralysed
one
• Treatment: Generally treatment is not
required

17. RLN PARALYSIS
• Bilateral RLN paralysis
 Aetiology: neuritis and trauma
(thyroidectomy) are the most common
causes. The condition is often acute in
onset
 Position of cords: as all the intrinsic
muscles are paralysed the vocal cords
lie in median or paramedian position
due to unopposed action of cricothyroid

18. RLN PARALYSIS-
CLINICAL FEATURES
• The airway is inadequate causing
dyspnoea and stridor but the voice
is good
• Dyspnoea and stridor become
worst during exertion or during
attacks of acute laryngitis
• Treatment: Tracheostomy / vocal
cord lateralization procedures

19. LATERALISATION OF
VOCAL CORD
• Aim to move and fix the cord in lateral position
to improve the airway
• Various procedures are
 Arytenoidectomy: can be done by external
approach, endoscopic or by using LASER
 Thyroplasty type 2
 Cordectomy: can be done through external,
endoscopic or by using LASER
 Nerve muscle implant: sternohyoid muscle
with its nerve supply is transplanted into the
paralysed posterior cricoarytenoid to bring some
movement

20. SLN PARALYSIS
• Unilateral
Usually it’s a part of combined
paralysis, isolated lesions are rare
Causes paralysis of cricothyroid
muscle and ipsilateral anesthesia of
the larynx above the vocal cord

21. SLN PARALYSIS-
CLINICAL FEATURES
• Voice is weak and pitch can not be
raised
• Occasional aspiration may be present
• Askew position of glottis as anterior
commissure is rotated to the healthy
side
• Shortening of the cord with loss of
tension
• As tension of the cord is lost , it sags
down during inspiration and bulges up
during expiration

22. SLN PARALYSIS
• Bilateral
 This is uncommon condition
 Both Cricothyroids are paralysed along
with anesthesia of upper part of larynx
 Etiology: surgical, accidental trauma,
neuritis, neoplastic (pressure by
metastatic lymph nodes)
 Clinical features: weak and husky voice,
aspiration causing cough and choking fits

23. SLN PARALYSIS- TREATMENT
• Depends on cause, neuritis
recovers spontaneously
• Troublesome aspiration requires
tracheostomy with cuffed tube and
esophageal feeding tube
• Epiglottopexy is an operation to
close laryngeal inlet to protect the
lungs from repeated aspiration, it’s
a reversible process

24. COMBINED (COMPLETE)
PARALYSIS
• Unilateral
 This causes paralysis of all the muscles of
larynx on one side except interarytenoid which
receives innervation from the opposite side
 Etiology: thyroid surgery is the most common
Etiology
cause
 It may also occur in the lesions of nucleus
ambiguus or that of the vagus nerve proximal to
origin of SLN
 Thus lesion may lie in medulla, posterior cranial
fossa, jugular foramen or parapharyngeal space

25. COMBINED (COMPLETE)
PARALYSIS
• Clinical features:
Vocal cord will lie in cadeveric
position
Healthy cords fails to compensate
This causes hoarseness of voice
and aspiration of liquids through the
glottis
Cough is ineffective due to air waste

26. COMBINED PARALYSIS-
TREATMENT
• Speech therapy
• Procedures to medialise the cord
Injection of Teflon paste
Thyroplasty type 1
Muscle or cartilage implant
Arthrodesis of cricothyroid joint

27. COMBINED PARALYSIS
• Bilateral
Both RLN and SLN are paralysed on
both sides
Both cords lie in cadeveric position
and there is total anaesthesia of the
larynx

28. COMBINED PARALYSIS-
BILATERAL
• Clinical features
Aphonia
Aspiration
Inability to cough
Bronchopneumonia

29. COMBINED PARALYSIS-
BILATERAL
• Treatment:
Tracheostomy
Epiglottopexy: epiglottis is folded
backwards and fixed to the
arytenoids
Vocal cord plication
Total laryngectomy

30. CONGENITAL VOCAL
CORD PARALYSIS
• May be unilateral or bilateral
• Unilateral is more common
• May be due to birth trauma, congenital
anomalies of great vessels of heart
• Bilateral paralysis may be due to
hydrocephalus, arnold-chiari
malformations, intracerebral hemorrhage
during birth, meningocoele, nucleus
ambiguus agenesis

31. PHONOSURGERY
• Surgical procedures designed to improve
quality of voice
 Excision of benign or malignant lesions by
Microlaryngeal surgery or laser
 Teflon paste injection to vocal cords
 Thyroplasty
 Laryngeal reinnervation procedures:
segment of anterior belly of omohyoid
muscle carrying its nerve and vessels is
implanted into thyroarytenoid muscle

32. THYROPLASTY
• ISSHIKI CLASSIFICATION
Type 1: medialization
Type 2: lateralization
Type 3: shortening
Type 4: lengthening ( tightening)