Differential Diagnosis:
Infantile Stridor
Amy Stinson
MS IV
KCUMB
Stridor

An expression of partial respiratory tract
obstruction 2° to external compression or
partial occlusion within the airway1
 Character & Intensity:
– Site & Degree of obstruction
– Airflow velocity & Pressure gradient
– Stridor
Stridor

Inspiratory – problem at or above vocal cords,
usually high pitched at cords, low pitched above
cords
– Laryngomalacia, unilateral cord paralysis

Expiratory – problem is below cords –
tracheobronchial tree, more prolonged
– Vascular compression

Biphasic – usually subglottic
– Subglottic stenosis, subglottic hemangioma, bilateral
cord paralysis
Laryngomalacia

Most common cause of stridor
 Most common congenital laryngeal abnormality
 “Congenital flaccid larynx” or “Inspiratory
laryngeal collapse”
 Inspiration:
– Prolapse of supraglottic structures
– Extreme infolding of “Omega-shaped” epiglottis and
aryepiglottic folds
Laryngomalacia

Photographs show a case of laryngomalacia during expiration
(A) and inspiration (B). Note the infolding of the aryepiglottic
folds.

www.entjournal.com/htmlDocs/Images/ped-0209.jpg
Laryngomalacia


Normal Vs Abnormal
www.meei.harvard.edu/.../images/laryngomal.jpg
Laryngomalacia

Signs & symptoms:
– Inspiratory stridor within a few days of birth
– Initially mild  more pronounced with a peak at 6 –9
–
–
–
–
mo4
Stridor is worse when supine and neck flexion: better
when prone and neck extension1
Symptoms worse when sleeping, feeding, or on
exertion
Most commonly – mild stridor that is self limited
Most cases spontaneously resolve by 2 yrs of age
Laryngomalacia

More Severe:
– Severe stridor, apneic episodes, feeding
problems, & FTT
–  pulmonary HTN & cor pulmonale

Presumed etiologies:4
– Abnormally pliable supraglottic cartilage
– Neuromuscular abnormalities
– GER
Laryngomalacia

DX:
– Endoscopy under local anesthesia
– Laryngotracheobronchoscopy to R/O other path
– Polysomnography to detect desaturations w/hypoxia or
hypercapnia

Treatment:
– OBSERVE
– Temp trach in severe cases
– Sx for 10%  supraglottoplasty which reduces amount
of laryngeal mucosa
– Anti-reflux meds
Laryngomalacia

“State Dependent” Laryngomalacia6
– Neurogenic factors would cause at states of
awareness – often paradoxical.
– Direct stimulation resolves

Discoordinate Pharyngolaryngomalacia6
– Assoc. with severe collapse and poor outcomes
– Need CPAP & nasal stents and poss. trach
Vocal Cord Paralysis
Second most common
congenital abnormality of
larynx4
Congenital & Bilateral is most
common presentation with
stridor and is usually seen in
males4
Unilateral paralysis on Left
seems to be more common
but less associated with
stridor6
Check nucleus ambiguous &
supranuclear tracts plus
Vagus nerve & branches3
www.meei.harvard.edu/.../images/laryngomal.jpg
Vocal Cord Paralysis

Etiology:
– Idiopathic
– CNS: Arnold-Chiari malformation
– CV: Congenital abnormalities of heart & great vessels
of Sx correction of
– Trauma: Repair of TE fistula, birth trauma, head injury
– Inflammatory: Guillian-Barre
– PNS: myotonic dystrophy, myasthenia gravis
Vocal Cord Paralysis

Signs & Symptoms:
– Asymp  acute airway
–
–
–
–
–
obstruction
High pitched
inspiratory stridor,
apnea, cyanosis
Hoarse, breathy cry
Weak cough
All more common with
bilateral palsy
www.meei.harvard.edu/.../images/laryngomal.jpg
Vocal Cord Paralysis

Dx:
– Fiberoptic endoscopy
– Laryngotracheobronchoscopy
– MRI

Tx:
– Unilateral: Observe, Speech therapy
– Bilateral: Tracheotomy, frequent endoscopies,
no Sx for at least a year – maybe longer
Vocal Cord Paralysis
www.meei.harvard.edu/.../imag
es/laryngomal.jpg
Subglottic Stenosis




3rd most common
congenital cause of
stridor
Subglottis is the
narrowest part of airway
& the only complete ring
(cricoid cartilage)
Congenital & Acquired
www.meei.harvard.edu/.../images/laryngom
al.jpg
Subglottic Stenosis2,4,5

Congenital:
– Soft tissue stenosis or cartilaginous stenosis
– Severe: stridor at birth
– Mild: intermittent stridor & resp tract infections

Acquired:
– Neonatal intubations, external trauma, high trach,
infection, burns
– Repeated failure of attempted extubation
– Gradual onset of stridor after extubation
Subglottic Stenosis1,2

Stenosis if < 4mm in
full term infant; < 3mm
in preterm infant
 Meyer-Cotton Grading
–
–
–
–
I: 0-50%
II: 51-70%
III: 71-99%
IV: no detectable lumen
–
www.meei.harvard.edu/.../images/laryngomal.jpg
Subglottic Stenosis

Decrease risk:
– Uncuffed,
polyvinylchloride tubes
– Smaller tubes
– Nasotracheal intubation
= less friction
–
www.meei.harvard.edu/.../images/laryngomal.jpg
Subglottic Stenosis

Treatment:
– Observe: Grade I, II, airway can increase with growth
–
–
–
–
of child
Tracheotomy: until reconstruction
Endoscopic: Laser can decrease granulation tissue, can
actually worsen with long term scarring
Laryngotracheal reconstruction: requires cartilage
grafts and stents, enlarges stenosed portion
Cricotracheal resection: excises stenosed portion,
higher success rate, but increased risk of recurrent
laryngeal nerve damage
Subglottic Hemangioma






A soft, compressible, bluish
tumor below true vocal cords
Female > male 2:1
50% have cutaneous
hemanigioma
Subglottis is most common
location – usually unilateral
Tend to proliferate from birth
– 1 yr then involute. Usually
resolved by 5 yrs.
www.childrensenthouston.com/images/laryngomal
Subglottic Hemangioma

Signs & Symptoms:
– Intermittent stridor that
progresses to biphasic
stridor with dyspnea and
cyanosis
– Originally dx as croup
www.meei.harvard.edu/.../images/laryngomal.jpg
Subglottic Hemangioma

Treatment
– Observe: if small
– Tracheotomy until involution
– Steroids – possible estrogen receptor  involution
– Laser therapy – good for hemostasis
– Surgical excision – becoming more common because of
stenosis from trach
– Interferon – alfa-2a has antiangiogenic activity when
hemangioma in proliferate phase
Less Common Causes of
Stridor

Dysphagia lusoria
 Laryngeal cysts
 Congenital laryngeal webs
 Laryngeal foreign bodies
 Respiratory papillomatosis
Dysphagia Lusoria
“Dysphagia of unclear etiology”
 Congenital anomalies of aortic arch:

– Double aortic arch
– Anomalous origin of R or L subclavian artery
– Kommerell’s Diverticulum – saccular aneurysmal
dilation at of ARSA or ALSA
– If LA or ductus present between subclavian and
pulmonary  complete vascular tracheobronchial ring

Presents as respiratory distress, dysphagia &
stridor
Dysphagia Lusoria

Dx:
– CXR
– Barium swallow w/
esophogram

Tx:
– Sx repair through
lateral thoracotomy
with lung
separation
Laryngeal Cysts2,4






Rare cause of Stridor
More superficial
Fluid filled
Ductal: MC, originate
from obstruction of
submucous gland
Saccular: in laryngeal
ventricles, usually
congenital
www.meei.harvard.edu/.../images/laryngo
mal.jpg
Congenital Laryngeal
Webs1,2,4






Embryology: Failure of
complete recanalization
Most common in anterior
glottis (fusion of ant
portion of vocal cords)
Abnormal cry & stridor
Incise thin webs
Excise and stent severe
webs
www.meei.harvard.edu/.../images/laryngoma
l.jpg
Laryngeal Foreign Bodies4

MC in kids 1-3 yrs
 Most inhaled objects pass through larynx
and lodge distally
 If lodged in larynx & partially obstructed
– Stridor, hoarseness, and cough
– Confirm w/X-ray
– Remove in OR
Respiratory Papillomatosis1,2,4

Most common neoplasm of larynx in children
 Dx: most common btw 2 –5 yrs
 Increased risk:
– First born, vaginal delivery, teenage mother
– HPV 6, 11
Gradual progression of dyspnea and stridor
Tx: surgical ablation w/CO2 laser  webs & scarring
References
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1. Rowe, LD. Pediatric Airway Obstruction. Otolaryngology – Head and Neck Surgery.
Current Surgery. Chap 38.
2. Kirby, GS. et al. Respiratory Tract and Mediastinum. Current Pediatrics. Chap 18.
3. Gormley, PK. et al. Congenital vascular anomalies and persistent respiratory
symptoms in children. International Pediatric Journal of Otorhinolaryngology. Nov
1999: 51:23-31.
4. Lange, et al. Current Opinion in Otolaryngology and Head and Neck Surgery.
Lippincott, Wilkins and Williams. Dec 1999. p 349.
5. Mossad, E. et al. Diverticulum of Kommerell: A review of a Series and a Report of a
Case with Tracheal Deviation Compromising Single Lung Ventilation. Anesth Analog.
2002:94:1462-4
6. Bent, J. Pediatric Laryngotracheal Obstruction: Current Perspectives on Stridor.
Laryngoscope. 2006: 116: 1059-1070
7. Sisk, EA. et al. Tracheotomy in Very Low Birth Weight Neonates: Indications and
Outcomes. Laryngoscope. 2006: 116: 928-933