Subglottic, supraglottic & translaryngeal stenosis

See also Subglottic stenosis information

During inspiration, oxygen passes into the nose, traverses the larynx (voice box) and then enters the lungs. The larynx is situated at the cross-roads of the air and food pipe. The vocal cords function to prevent passage of food and liquids into the the lungs.

The larynx is divided into:

• supraglottis which is situated between the base of tongue and the vocal cords,
• glottis composed of the vocal cords and the false vocal cords
• subglottis which is a part of the larynx situated just below the vocal cords and upto the trachea. In children, the subglottis is the narrowest part of the airway, and the same is at the level of the vocal cords in adults.

There are several causes of laryngeal (narrowing) stenosis. It could be congenital and present from birth or acquired (secondary to intubation at birth, prolonged intubation due to other causes-cardiac, pulmonary, neurological, accidents). Frequently the cause is of mixed etiology, i.e an intubation done over a pre-existing minor or undetected congenital stenosis.

Laryngeal stenosis causes stridor, severe breathlessness and the patients are deemed to get a tracheostomy (canula / tube in the neck), which bypasses the stenosis to establish an airway below the level of the stenosis.

Treatment for laryngeal stenosis begins with an endoscopic evaluation. The entire aerodigestive tract is evaluated under anesthesia conditions that mimic sleep and maintain the airway dynamics.

Surgery is of 2 types:

• expansion procedures wherein the airway is expanded using cartilages that are harvested from ribs.
• resection and anastomosis, which allows complete removal of the narrowed area and re-attaching the normal airway segments to each other.

Both these types of surgeries can be done in one or two stages.

Single-stage operation requires the child to have a nasotracheal tube and admission in the intensive care for 5-7 days.

Operations done in 2 stages will have a stent (Monnier’s Laryngotracheal LT Mold) and a tracheostomy. The LT mold is used to calibrate the expanded airway and stabilizes the cartilage reconstruction. The LT mold is kept for weeks to months depending on each individual case. A separate endoscopic procedure is done to remove the stent. The tracheostomy canula is removed after successful decannulation trials (removal of the tracheostomy canula).

Severe narrowing of the subglotis will need a cricotracheal resection (removal of the stenotic segment followed by re-anastomosis of the airway).

None of these procedures inhibit the normal growth of the trachea and the child.

It must be remembered that, there is always a trade-off between the AIRWAY and the VOICE when performing surgical interventions on the airway. Priority is given to decannulation which changes the quality of life for the patient and avoids multiple problems associated with the tracheostomy. Quality of voice can be improved with several endoscopic procedures that can be done after a successful decannulation.