2. Laryngotracheal Stenosis
What is it,
Laryngotracheal stenosis (LTS) is a narrowing of the
upper airway between the larynx and the trachea
with potentially devastating consequences, including
respiratory failure, cardiopulmonary arrest, and
death. The upper airway is comprised of the larynx,
glottis, subglottic region, and trachea
3. Etiology
• Recognized causes of laryngeal stenosis include:
iatrogenic (ex. complication of endotracheal intubation),
autoimmune, infectious, neoplastic, traumatic, and
idiopathic. Autoimmune diseases such as systemic lupus
erythematosus, rheumatoid arthritis, vasculitis,
sarcoidosis, and scleroderma, among others, can cause
laryngotracheal stenosis. Infectious causes include
bacterial tracheitis, viral papillomatosis, and tuberculosis.
Neoplasm at the level of the larynx or trachea can also
cause narrowing of the airway, with squamous cell
carcinoma and adenoma beiNg the most common
malignancies in this setting.
• Direct injury to the trachea by trauma, inhalation burns,
or radiation are a few causes of traumatic laryngotracheal
stenosis.
4. Pathophysiology
• The most narrow part of the adult airway is at the
subglottic space at the level of the cricoid cartilage,
which extends from the inferior part of the vocal cords to
the lower part of the cricoid cartilage.
• This area is only a few centimeters in length but can be
commonly injured during endotracheal intubation, as the
endotracheal tube makes contact with the posterior
aspect of the subglottic space during intubation.
Prolonged intubation can also cause laryngotracheal
stenosis
• Prolonged intubation can also cause laryngotracheal
stenosis when the cuff pressure exceeds the mucosal
capillary perfusion pressure (approximately 35 mmHg),
which can lead to ischemia, ulceration of the posterior
mucosa, and subsequent fibrotic strictures.
5. Evaluation
Laryngotracheal stenosis can be
evaluated by laryngoscopy or
bronchoscopy. The clinician may
obtain computed tomography (CT)
scan of the neck in severe cases in
which the obstruction does not
allow for direct laryngoscopy or
patients who have a traumatic
injury to the trachea and in
planning for surgical treatment. CT
scan may demonstrate artificial
extra-tracheal stenosis, such as in a
massive goiter, owing to the
dependent position of the trachea
when obtaining such scans.
Performing spirometry on these
patients helps establish a baseline
and monitor their status over time.
6. Classification
• There are three classification systems based on
anatomic characteristics that are derived from
intraoperative findings. The Cotton-Myer
classification is based on percent stenosis (I = < 50%
obstruction; II = 51% to 70% obstruction; III = 71% to
99% obstruction; IV = Complete obstruction). The
Lano classification is based on subsite involvement (I
= one subsite involvement; II = two subsite
involvement; III = three subsite involvement, with the
subsite meaning the glottis, subglottis, and trachea).
7. Treatment / Management
• Treatment options for LTS include endoscopic
dilatation, surgery, stent placement, laser therapy, or
immunosuppression to restore airway patency,
depending on the underlying etiology as well as
degree and complexity of stenosis.
• Bronchoscopic Approach,
Bronchoscopy may be used for mechanical dilation,
laser therapy, and stenting to treat laryngotracheal
stenosis. These treatment modalities may have limited
use in subglottic stenosis due to anatomical challenges
8. Endoscopic Mechanical Dilation
• Endoscopically-guided dilation is performed using
several devices, including gum-tipped bougies,
endotracheal tubes, or balloon catheters. It could be
performed in the outpatient setting for a selected
group of patients. This route has more favorable
outcomes in regards to voice preservation compared
with patients who have stenosis less than 2 cm from
the vocal folds, or those who have stenosis in several
levels. Endoscopic dilation should be the first-line
treatment for simple stenosis, whereas more complex
stenoses require an interprofessional approach and
possible surgical evaluation. The average patient may
be able to go for approximately one year without
requiring subsequent dilations.[
9. Tracheal Stenting
• Tracheal stenting is a palliative option for patients
with advanced and unresectable cancer-causing
airway obstruction. As stated above, stenting is a
challenging and risky approach that requires a risk-
benefit conversation with the patient. Higher
performance status before surgery correlates with
better patient outcomes.
