2. ANATOMY OF THE LARYNX
• hollow musculoligamentous structure with a cartilaginous
framework
• Location: C4-6 Vertebra
• suspended from hyoid bone above and attached to trachea
• It is highly mobile in the neck
• moved up and down and forward and backward by the
action of extrinsic muscles
• It is composed of Laryngeal cartilages :
three large unpaired cartilages - cricoid, thyroid, and
epiglottis
three pairs of smaller cartilages – arytenoid, corniculate,
and cuneiform)
5. laryngeal inlet
• anterior border -by mucosa covering the
superior margin of the epiglottis;
• lateral borders -by mucosal folds
(aryepiglottic folds)
• posterior border - by a mucosal fold that
forms a depression (interarytenoid
notch)
6. Cavity of the larynx
• The cavity is divided into two major
compartments by the vocal folds:
• Supraglottic space – above the vocal folds up
to the epiglottis
• Subglottic space –below the vocal folds up to
the lower border of the cricoid cartilage.
12. Histology
• The epithelial linning is pseudo stratified squamous
epithelium
• Subepithelial tissues: three layered lamina propria
• Vocalis and thyroarytenoid muscle
15. Physiology of the larynx
• Laryngeal Function
– Airway protection
– Breathing Passage
– Vocalization/Phonation
– Aid in the clearance of secretion
• Symptoms of Laryngeal Anomalies
– Feeding difficulties-chocking
– Airway obstruction-stridor
– Abnormalities of Phonation-horsenes ,dysphonia
,aphonia
16. Airway protection
• First level- Epiglottis, aryepiglottic folds &
arytenoids
• Second level- False vocal folds
• Third level- True vocal folds
• Anomalies of any of this structures lead to
aspiration and swallowing dysfunction
– Symptoms- coughing, choking and gagging
episodes, stasis of secretion, and recurrent
pneumonia
17.
18. Phonation
• Physical act of sound production by means of
passive vocal fold interaction with the exhaled
airstream
• Requirements
– Adequate breath support
– Approximation of vocal folds
– Favorable vibratory properties
– Favorable vocal fold shape
– Control of length and tension
26. Laryngomalacia
• Most common congenital laryngeal anomaly (50-
75%)
• Most frequent cause of stridor in children
• Male predominance 2:1
• Flaccidity of supraglottic laryngeal tissues
• Characterized by inward collapse of supraglottic
structures during inspiration
27. Laryngomalacia
• Anatomic Abnormalities
– Epiglottis
• Long tubular
• Displaced posteriorly on
inspiration
• Inferior collapse to the
vocal folds
– Short aryepiglottic folds
– Inward collapse of
aryepiglottic folds
(primarily cuneiform
cartilages)
– Anteromedial collapse of
the arytenoid cartilages
28. Laryngomalacia
symptoms
• Airway obstruction
– Mild to moderate obstruction
• Stridor exacerbated by exertion
– Crying, agitation, feeding or supine position
– Severe obstruction
• Substernal retraction
• Pectus excavatum with chronic severe obstruction
– Other complications
• Feeding difficulties
• GERD
• Failure to thrive
• Cyanosis, cardiac failure & death
29. Laryngomalacia
• stridor
– Inspiratory stridor
• Intermittent low-pitched
– Starts within first two weeks of birth
– Peak at 6 months and most are symptom free by 18 to 24
months (75%)
Diagnosis
– Awake flexible fiberoptic laryngoscopy
• Visualize supraglottic anatomy and collapse
– Direct laryngoscopy and bronchoscopy- evaluate for
synchronous lesions (27%)
31. Subglottic Stenosis
– Incomplete laryngeal lumen recanalization
– due to thickening of soft tissue of subglottic space or
maldevelopment of cricoid cartilage
35. Vocal Cord Paralysis
Treatment
• Bilateral
– Tracheotomy may be necessary (50%)
– Lateralizing one or both paralyzed vocal cords
– Excisional procedure
• Tissue removed from posterior glottis
36. Inflammation of the Larynx
Acute Laryngotracheobronchitis (Croup)
• inflammation of tissues in subglottic space ±
tracheobronchial tree
• swelling of mucosal lining and associated with thick,
viscous, mucopurulent exudate which compromises upper
airway (subglottic space narrowest portion of upper
airway)
• normal function of ciliated mucous membrane impaired
Etiology
• viral: parainfluenzae I (most common), II, III, influenza
A, and B, RSV
37. Acute Laryngotracheobronchitis (Croup)
Clinical Features
• age 4 months to 5 years
• preceded by URTI symptoms
• generally occurs at night
• biphasic stridor and croupy cough (loud, sea-lion bark)
• appear less toxic than with epiglottitis
• supraglottic area normal
• rule out foreign body and subglottic stenosis
• “steeple-sign” on AP x-ray of neck
• if recurrent croup, think subglottic stenosis
38. Acute Laryngotracheobronchitis (Croup)
Treatment
• racemic epinephrine via nebulizer every1 to 2 hrs PRN
• systemic corticosteroids (e.g. dexamethasone, prednisone)
• adequate hydration
• close observation for 3 to 4 hours
• intubation if severe
• hospitalize if poor response to steroids after 4 hours and
persistent stridor at rest
• consider alternate diagnosis if poor response to therapy
(e.g. bacterial tracheitis)
39. Acute Epiglottitis
• acute inflammation causing swelling of supraglottic
without involvement of vocal cords
Etiology
• H. influenzae type B ,relatively uncommon due to HiB
vaccine
Clinical Features
• any age, most commonly 1 to 4 years
• rapid onset
• toxic-looking, fever, anorexia, restlessness
• cyanotic/pale, inspiratory stridor, slow breathing, lungs
clear with decreased air entry
• prefers sitting up, open mouth, drooling, tongue
protruding, sore throat, dysphagia
40. Acute Epiglottitis
Investigations
• investigations and physical examination may lead to complete
obstruction, thus preparations for intubation or tracheotomy must be
made prior to any manipulation
• Seek ENT/anesthesia consultation
• lateral neck radiograph – cherry-shaped epiglottic swelling (“thumb
sign”) – only if stable
• WBC (elevated)
Treatment
• secure airway & get IV access with hydration
• antibiotics – IV ceftriaxone
• Oxygen suppplementation
42. Laryngeal cancer
• Originates on the true VC(75%)
• Hoarseness in elder age groups, >2 weeks strong early warning
• Sites other than the VCs do not cause hoarseness leading to
delay in diagnosis
Presentation
- Hoarseness
- Immobile or fixed VCs
- Verrucous, exophytic or infiltrative mass
Management
• Surgery with radiotherapy primary mode
• chemotherapy
