Subglottic Stenosis in Children Treatment & Management

No known medical therapy for mature subglottic stenosis (SGS) exists. If a granular or immature subglottic stenosis (SGS) is noted, as shown in the image below, treatment of the inflammatory process with oral or inhaled steroids sometimes can decrease the severity of disease. Findings from animal studies have shown that treatment with antibiotics and steroids can help improve an immature or granular subglottic stenosis (SGS); however, the optimal treatment duration is unknown. Evaluate each case on an individual basis. Once subglottic stenosis (SGS) is mature, medical therapy is almost always unsuccessful. However, suspected GER must receive aggressive medical treatment for optimal surgical results.

Endoscopic procedures

For mild or granular subglottic stenosis (SGS), investigators have reported success with serial endoscopic dilation with or without steroid injections. Healy popularized the use of the carbon dioxide laser as an option for soft circumferential subglottic stenosis (SGS). ^[18] This procedure involves making incisions in 4 quadrants, followed by dilation. This technique is best used in conjunction with steroids when an immature or granular subglottic stenosis (SGS) is present. Normally, use of a laser causes recurrence of the scar in a mature stenosis; however, in unusual types of mature subglottic stenosis (eg, spiraling subglottic stenosis), improvement may be accomplished with a few serial carbon dioxide laser excisions, shown below.

In addition, topical application of mitomycin has been used in an attempt to inhibit scars from reforming after an endoscopic lysis of either mature or granular subglottic stenosis (SGS). Mitomycin is an antineoplastic agent that inhibits fibroblast proliferation and activity. Varying reports have shown both benefit and no benefit when used topically for subglottic stenosis (SGS). When evaluating the studies, evidence suggests that mitomycin is beneficial in both acute granular stenosis and mature stenosis, although it may work better in acute trauma to the subglottis that results in a fresh or granula scar. A controlled study on the use of mitomycin as an adjunct to laryngotracheal reconstruction, as well as several animal studies, have show no benefit to its use in mature stenosis. Hueman and Simpson, in December 2005, reported that 4.7% of patients developed local complications of fibrinous debris at the operative site, with no mention of any system complications. ^[19]

A prospective study by Avelino et al indicated that in children who undergo balloon laryngoplasty for acquired subglottic stenosis, success is predicted by the presence of acute stenosis and of a less severe grade of stenosis, as well as by younger age and the absence of tracheotomy. In the study, which included 17 patients with acute subglottic stenosis and 31 with chronic stenosis, the success rate for balloon laryngoplasty was 100% for the acute patients and 39% for children with the chronic condition. ^[20]

A retrospective study by Maresh et al found that endoscopic balloon dilation is less likely to be successful in severe (grade 3 or 4) pediatric subglottic stenosis compared with laryngotracheoplasty, with initial treatment with balloon dilation failing in 13 out of 13 patients (100%) with severe stenosis and in 4 out of 14 patients (29%) with grade 1 or 2 stenosis. ^[21]

Open reconstruction of subglottic stenosis

Base the approach to open reconstruction of subglottic stenosis (SGS) on the location and degree of scarring. Reconstruction often may be unnecessary for subglottic stenosis (SGS) classified as grades I and II on the Myers and Cotton scale (ie, as much as 70% obstruction of the subglottic airway). When surgery is necessary on the basis of the severity of symptoms, perform an open reconstruction in mature circumferential subglottic stenosis (SGS). The surgical technique depends on adjacent areas of scarring and on the location and appearance of subglottic stenosis (SGS). For severe subglottic stenosis (SGS), classified as grades III and IV (ie, >70% luminal obstruction), laryngeal expansion is almost always necessary.

The goals of open reconstruction are decannulation or resolution of symptoms, with preservation of the voice by expanding the subglottic airway and stabilizing the expanded frame.

Various procedures for treating subglottic stenosis (SGS) include the following: (1) anterior cricoid split (ACS); (2) single staged procedure: anterior cartilaginous grafting with costal, thyroid, or auricular cartilage ^[22] ; (3) multistaged procedure applying (a) anterior and posterior cartilage grafting, usually with costal cartilage, (b) anterior cartilaginous grafting with a posterior cricoid split and stent placement, (c) posterior grafting with costal cartilage, and (d) anterior and posterior costal cartilage with lateral cricoid splits; and (4) cricotracheal resection.

Anterior cricoid split

In 1980, Cotton and Seid described the use of anterior cricoid split (ACS) to avoid tracheotomy in neonates with SGS, good pulmonary and cardiac function, and airway obstructive symptoms after extubation. Anterior cricoid split (ACS) allows decompression of the edematous submucosal glands of the subglottis and thus, expansion of the airway. ^[2]

Criteria have been developed to identify the children who are likely to benefit from anterior cricoid split (ACS). These include the following: (1) patient weight of more than 1500 g, (2) failure to extubate in identified subglottic stenosis (SGS), (3) oxygen requirement of less than 30%, (4) no active respiratory infection, and (5) good pulmonary and cardiac function.

Transport the already intubated child from the ICU, and make horizontal incisions over the cricoid cartilage. Divide the strap muscles in the midline, and identify the thyroid cartilage, costal cartilage, and upper tracheal rings, shown below.

Place Prolene stay sutures (4-0) around each side of the anterior component of the cricoid ring. Use a double-sided beaver blade to make an incision in the cricoid ring as far as the tracheal rings and the inferior third to half of the laryngeal cartilage. Then, reintubate the child with an endotracheal tube appropriately sized for his or her age. Do not expand the airway more than necessary, since pressure on the mucosa and persistent subglottic stenosis (SGS) can result.

Loosely close the skin over the wound, and place a rubber band drain. Mark the Prolene sutures in the cricoid as left and right. Generally, leave the nasal tube in place for 7-10 days. If self-extubation occurs, reintubate from above. Should the endotracheal tube protrude through the airway into the neck during reintubation, the stay sutures can be lifted and crossed to block the cricoid split incision and to direct the endotracheal tube down the trachea. If this procedure is unsuccessful, the stay sutures can be pulled up to the neck and opened so that a tracheal or endotracheal tube can be placed in the airway until the child can be returned to the OR for intubation through the mouth.

Administer antibiotics and antireflux medication during the intubation period. Begin the administration of steroids 24 hours before extubation and continue for 48 hours afterwards. Usually, the tube can be removed after 7-10 days. If an air leak around the endotracheal tube is present with a pressure of less than 20 cm of water, extubation should be successful. If airway obstruction that is not amenable to medical therapy (including racemic treatments and steroids) occurs after extubation, return the patient to the OR for evaluation, or immediately reintubate in the ICU if necessary. Complications of anterior cricoid split (ACS) are unusual and include pneumothorax, pneumomediastinum, subcutaneous emphysema, wound infection, and persistent subglottic stenosis (SGS).

The images below were obtained in a 4-month-old infant born 3 months prematurely who required intubation and ventilation for 3 months.

She had a grade III SGS and underwent anterior cricoid split (ACS) with intubation and ventilation for 1 week in the ICU. The image below shows the subglottis 1 week after extubation.

The size of the larynx was determined with an endotracheal tube, and subsequent dilation of the soft mild restenosis is depicted in the image above and the image below.

The child received oral steroids for 5 days and underwent follow-up bronchoscopy, shown below, 2 weeks later.

Single-stage laryngotracheoplasty with cartilage expansion

In 1991, Seid et al reported the use of single-stage laryngotracheoplasty (LTP). ^[6] Their approach to the airway resembles anterior cricoid split (ACS); however, instead of leaving the area anterior to the fibrosis, a piece of costal cartilage was placed. The procedure was performed in 13 patients with subglottic stenosis (SGS) grades I-IV. However, the procedure failed in a patient who had complete glottic and subglottic stenosis (grade IV). The researchers indicated that grade IV subglottic stenosis (SGS) was a contraindication to single-stage LTP. Two patients had grade III subglottic stenosis (SGS) and a successful result.

Seid et al stressed the postoperative course in these patients. Instead of leaving the endotracheal tube in place for 7-10 days, they checked the air leak surrounding the endotracheal tube on a daily basis and removed it when the pressure of the leak was less than 20 cm of water. ^[23]

The authors were also concerned about the transient weakness of the extremities caused by neuromuscular blockade and hydrocortisone. They used vecuronium and benzodiazepines for sedation. Aggressive pulmonary toilet was stressed, since wandering atelectasis can be present in a patient who is ventilator dependent for as many as 10 days. The authors stressed the repeated use of a full range of passive extremity motions to decrease the likelihood of transient muscle weakness during the period of induced paralysis for long-term intubation.

Seid et al believed that selection of patients was critical and that any child with difficulties in addition to subglottic stenosis (SGS); eg, tracheal problems, true vocal cord paralysis) was not a good candidate for single-stage LTP. The procedure could fail after extubation for reasons other than the newly repaired subglottic stenosis (SGS).

In 1995, Rothschild et al reviewed the effectiveness and complications of single-stage LTP. ^[24] In 104 patients from the Children's Hospital of Cincinnati, repair was successful in 86-92%, depending on the year of correction. The authors further reported that they did not use paralysis in their patients during the 5- to 10-day period of endotracheal tube placement; they used sedation with chlorohydrate and benzodiazepines instead. In fact, if the patient could tolerate nasotracheal intubation without much difficulty, they were allowed to engage in their usual activities, including eating, playing, and walking. (A modified cap placed on the endotracheal tube prevents crust formation in the tube and airway during these activities.)

Rothschild et al believed that younger children require heavier sedation and increased ventilation secondary to decreased respiratory effort. Neuromuscular paralysis usually was avoided. Among their 104 patients, the researchers found neuromuscular weakness in only one. They did not comment about the presence or absence of pulmonary atelectasis.

The average duration of endotracheal tube placement in their patients was 9 days. They did not explain why endotracheal tubes were in place longer than 10 days (as long as 26 d) in 37 children. Twenty-three children, however, had a posterior costal cartilage graft, which normally requires the use of stents for at least 2 weeks to stabilize the cartilaginous framework.

Seid and Cotton agreed that ICU staff who are knowledgeable and attentive are important to the success and safety of the procedure.

In 1991, Lusk and Muntz also described a single-stage LTP in which auricular cartilage is used for reconstruction when an anterior subglottic stenosis (SGS) is repaired. Patients had endotracheal tubes in place for 7-10 days, similar to the duration of intubation in patients in whom an ACS was performed. Lusk and Muntz sutured the cricoid to the strap muscles to help maintain airway patency; their success rate was similar to that of other procedures (ie, approximately 80-90%). This author's experience with the use of auricular cartilage has been less successful. If significant anterior subglottic stenosis (SGS) exists, use of cartilage that is rigid enough to maintain the splay of the cricoid cartilage usually is necessary to ensure continued expansion after extubation.

Zalzal added to the efficiency of the anterior cartilage single-stage procedure by describing the technique of carving the harvested rib into the shape of a boat with flanges on each end, as shown below.

In this technique, cartilage extends outside the lumen of the trachea, over the cricoid and tracheal rings, to help prevent the lumen from prolapsing into the airway.

With this technique (once any air leak is sealed during the surgery), extubation can be performed without fear of the cartilage requiring further stabilization or prolapsing into the airway.

After the procedure has been performed and the child has been admitted to the ICU, air leaks from the neck are checked on a daily basis. Usually, the air leak seals within 48-72 hours; extubation can be accomplished with confidence that the graft is stabilized. In this way, children can avoid the complications of long-term intubation mentioned above.

Reports of use of the superior section of the thyroid cartilage, as well as the septal cartilage, as grafting material exist. These materials, along with the auricular cartilage, usually do not provide much support. Instead, they act mainly as a patch over the divided area of the cricoid region. In these situations, the stent provides most of the force necessary to keep the lumen open while the surrounding area heals. Some of the other types of cartilage can be used in conjunction with ACS to improve that success rate of the procedure, which traditionally has been 70-80%.

Richardson and Inglis performed a prospective study to compare the cricoid split procedure with and without costal cartilage grafting for the treatment of acquired subglottic stenosis (SGS) in infants younger than 6 months in whom extubation in the ICU failed. The researchers found that results were improved in 90% of patients in whom cartilage was placed between the cricoid rings to expand the airway, compared with 56% in whom cartilage was not placed. This study was prospective and included only 20 patients, but its findings indicate that placing the lumen expander at the time of surgery greatly improves the likelihood that extubation succeeds and adequate airway is maintained.

Zalzal and Choi pointed out, however, that when the results of laryngotracheal reconstruction was evaluated in 48 patients aged 4 years or younger, success was decreased in children younger than 25 months compared with that of children aged 2-4 years. ^[25] (Note that the patients < 2 years had subglottic stenosis that was less severe than that of the older patients.) Zalzal and Choi still recommended laryngotracheal reconstruction in younger patients because the procedure may aid the child's speech and language development and help prevent tracheotomy complications.

Anterior and posterior grafting

For severe subglottic stenosis (grade III-IV), anterior and posterior cricoid splitting with costal cartilage grafts placed anteriorly and posteriorly has been effective in expanding the lumen and allowing decannulation. Most authors, including Zalzal and Cotton, agree that when a posterior graft is used, cartilage of sufficient strength must be placed posteriorly to keep the airway expanded. ^[26] Both Zalzal and Cotton have reported success rates higher than 90% with decannulation, frequently achieved with a single procedure. Occasionally, revision surgery is needed.

Often, the posterior graft is formed into an ellipse or elongated hexagon and placed so that the perichondrial side of the graft is flush with the mucosa of the posterior subglottic and tracheal wall. Occasionally, flanges can be fashioned on the posterior that can be placed posteriorly and outside the lumen in a manner similar to that of the boat graft (described by Zalzal), which is placed anteriorly. For a posterior graft, sutures to the posterior cartilage split are all placed individually prior to sliding the graft in position, as shown below, at which time the sutures can be tied. Sied described using fibrin glue in an animal study to keep a posterior graft in place, avoiding the arduous task of suturing it in.

Place the anterior graft in a similar fashion. Construction of the flanges on the anterior graft is not as critical as it is with a single-stage procedure, since children require stents for a minimum of 2 weeks. Usually, stents are used for 4-6 weeks when anterior and posterior grafts are placed and the tracheotomy is maintained. Once the stent is removed, follow-up bronchoscopies are performed to confirm the stenosis has not recurred before the patient is decannulated. Maintenance of a patent airway can be is evaluated with further bronchoscopies.

Usually, an Aboulker stent or Montgomery T tube (natively as depicted below, or cut to fit and used like an Aboulker stent, which are no longer commercially available) is used. See the images below.

Other types of stents also have been used. Often, if the collapse or scar extends into the area of the tracheotomy site, longer-term stent placement is required with an Aboulker stent that is attached to a metal Holinger tracheotomy tube with wire, depicted below, or a Montgomery T tube.

Complications of short-term stent placement (4-6 wk), such as granulation tissue and scarring from the distal end of the short stent, can be prevented with longer-term techniques for stent use.

The surgical approach for anterior and posterior grafting is similar to the approach for ACS and anterior cartilage grafting. Specific care for the posterior cricoid split with or without grafting requires visualization of the esophagus after the posterior cricoid cartilage has been incised. During division, take care to spread the cartilage to identify the esophageal mucosa so that no inadvertent injury occurs. Additionally, make the incision in the midline to prevent injury to the recurrent laryngeal nerve and to ensure that an appropriate site is created for placement of the graft.

Partial cricotracheal resection

In Switzerland, Monnier first reported the use of partial cricotracheal resection in 31 pediatric patients with grade III and IV stenosis in whom decannulation with anterior-posterior grafting failed. The decannulation rate after cricotracheal resection was 97%. Cotton and others began to evaluate the use of cricotracheal resection because of failures with grade III and grade IV stenoses. Investigators in the "Cincinnati Experience" recently reported that decannulation occurred in 90% of children with refractory grade III and IV stenoses.

The best candidates for partial cricotracheal resection are patients with severe subglottic stenosis (grade III-IV) without associated glottic pathologic conditions and with a margin of at least 4 mm in the healthy airway below the vocal folds and above the stenosis. This space allows resection away from the glottic larynx, with anastomosis of healthy mucosa. Expect significant glottic edema to last 4-6 weeks; use a tracheotomy or T tube during the postoperative period to protect the airway until the edema resolves.

Perform the procedure with the patient under general anesthesia; the approach to the larynx and trachea is similar to that of other laryngotracheal reconstructive procedures. Vertically enter the airway with the beaver blade in the midline at the level of the cricoid. Make the incision superior to the inferior margin of the thyroid cartilage and inferior to the second tracheal ring. The superior extent of the stenosis can be defined at endoscopy while simultaneously and directly viewing the open wound, so that a precise view of the scarred subglottic segment can be achieved. Make a horizontal cut just above the superior extent of the stenosis, from the anterior aspect to the posterior aspect, stopping at the level of the cricothyroid joint. By staying anterior to the cricothyroid joint at this level, injury to the recurrent laryngeal nerve can be prevented.

Make lateral cuts inferior to the cricothyroid joints, and continue inferiorly through the lateral aspects of the cricoid cartilage to expose the posterior cricoid plate. Approach the inferior area of the stenosis, and place stay sutures in the distal normal tracheal segment. Incise the trachea just below the inferior aspect of the stenosis through the anterior lateral portions of the trachea down to the membranous tracheal wall, then dissected this from the esophageal wall at the superior aspect. Connect the superior incision and remove the segment. Next, suture the uninvolved part of the trachea to the anterior thyroid ala and the exposed posterior cricoid plate.

During the dissection from the inferior aspect to the superior aspect, take care to dissect in a perichondrial plane over the cricoid to prevent injury to the recurrent laryngeal nerve. If identification of the esophagus is difficult during this portion of the procedure, a palpable dilator can be placed in the esophagus to delineate the esophageal wall. Before anastomosis, remove the scar tissue from the inner aspect of the posterior cricoid plate by using a small curet or drill. Perform a hyoid release procedure to decrease tension at the suture line. In addition, dissect the trachea until 4-5 rings are mobilized to aid in decreasing tension on the suture line. In addition, place 2-3 additional tension-releasing sutures on the thyroid ala and the upper tracheal rings to help release tension from the suture line. Place Proline stitches (0-0) from the chin to the chest of the child to keep the head flexed for a week.

In an older child with minimal glottic involvement, a single-stage procedure can be performed with nasotracheal intubation of 7-10 days' duration. In younger children with more severe glottic involvement, a Montgomery T tube can be placed for 4-6 weeks. Take meticulous care to prevent plugging of the T tube and resultant airway obstruction. Stern and Cotton recently reported good results with decreased morbidity with T tubes in children.

The most important part of laryngotracheal reconstruction is the preoperative assessment. Assessment involves direct bronchoscopy with an evaluation of the severity and level of stenosis. If the stenosis is defined properly, the correct procedure can be used for the best surgical outcome.

Additionally, evaluate the child's pulmonary status and presence or absence of GERD. The pulmonary status, including the amount of oxygen required by the patient, may determine whether laryngotracheal reconstruction should be attempted.

Evaluate the neurologic status as well. Children who have severe neurologic delays may need a tracheotomy for other reasons than subglottic stenosis (SGS), such as access for suctioning of thick secretions or to bypass obstruction from a malacic pharynx or supraglottic larynx.

Specific technical tips exist for each procedure; these have been elucidated earlier in this section (see Surgical therapy). Often, laryngoscopy performed before and during the procedure helps in preventing iatrogenic injury to the larynx and ensures the correct placement and extent of laryngeal incisions.

Postoperative care is critical in children. As stated earlier, any child requiring an ICU stay may have difficulties while receiving intubation and ventilation. Meticulous care from health care providers in the ICU may decrease the number of complications.

Children who undergo various laryngotracheal reconstruction procedures may have different follow-up care and courses, depending on the procedure performed. If a single-stage laryngotracheal reconstruction or ACS has been performed, bronchoscopy at extubation is not necessarily required; such decisions are left to the surgeon. However, 1-3 weeks after the procedure, bronchoscopy can be used to assess for any complications. Some authors examine the children after laryngotracheal reconstruction only if they have difficulty.

The author often performs laryngoscopy and bronchoscopy 1-2 weeks after extubation to evaluate the airway, since granulation tissue often forms in this period, as shown in the image below, and can lead to airway obstruction and scarring.

A carbon dioxide laser can be used to remove and control the granulation tissue well, depicted in the images below. Certainly, any time the child has airway obstructive symptoms, bronchoscopy should be considered.

In a child undergoing 2-stage laryngotracheal reconstruction with grafting and stent placement, the tracheotomy remains in place. The length of follow-up is determined by the duration of stent placement and the quality and quantity of symptoms after stent removal. For short-term stent placement (4-6 wk), follow up is 2 weeks after stent removal.

If this appears satisfactory, bronchoscopy should be performed at 4 weeks. In the interval, capping of the tracheotomy can be performed intermittently to evaluate for obstruction. If the bronchoscopy at 6 weeks is satisfactory, attempted decannulation can be considered. Prior to decannulation, the tracheotomy tube is usually downsized and plugged intermittently. If the child tolerates plugging, a sleep study can be performed, or the child can be decannulated and watched in the ICU or in a regular hospital room while monitored over night, depending on the individual case. Various methods to evaluate adequate airway prior to decannulation are available.

Walner and Cotton recommend repeat endoscopy at 1, 3, 6, 12, and 24 months after reconstructive surgery. This pattern allows long-term evaluation and detection of a recurring stenosis before it reaches a critical stage. Walner and Cotton also recommend capping and downsizing the tracheotomy in the hospital before decannulation.

For excellent patient education resources, see eMedicineHealth's patient education article Bronchoscopy.

Complications include the following:

Failure to correctly repair the stenosis occurs more often in severe stenosis than in moderate or mild stenosis. Zalzal and Choi examined 27 patients in whom laryngotracheal reconstruction failed and found that failure was related to the following: ^[25]

• Inappropriate choice of graft

• Inappropriate choice of stent

• Inappropriate length of stent

• Inappropriate duration of stent placement

• Inadequate assessment and endoscopy

• Poor postoperative follow-up

• Anterior suprastomal collapse

• Slipped Aboulker stent

• Interactive progression of GERD

• Keloid formation

• Failure to repair all abnormalities noted at preoperative evaluation

Injury to recurrent laryngeal nerve has been reported in a single case of cricoid tracheal resection. Avoidance techniques are outlined in Surgical therapy.

The voice quality of patients with glottic stenosis and subglottic stenosis (SGS) is decreased and never restored to the preoperative state. However, once the subglottic stenosis (SGS) is repaired, subglottic pressure can be increased to increases volume and improve speech quality. See the images below.

If an anterior laryngeal fissure is required to repair the subglottic stenosis (SGS), voice quality can worsen, even if the anterior cartilage is displaced only mildly. Therefore, if possible, avoid dividing the anterior commissure.

Complications from laryngotracheal reconstructive surgery itself include pneumothorax, pneumomediastinum, neck wound infection, chest wound infection, and emphysema.

Complications during the postoperative ICU course can include those of laryngotracheal surgery itself in addition to atelectasis of lung segments, pneumonia, and neuromuscular weakness with the use of paralytic agents and steroids.

The outcome of laryngotracheal reconstruction depends on its grade and the procedure performed. Most authors report success rates of 80-90% when the patient has undergone successful preoperative evaluation and when the appropriate surgery has been performed, as shown in the images below.

The presence of acute or chronic respiratory illness, GER, or a reactive larynx may decrease the success rate. Choi and Zalzal showed that age can affect success rates; scars are more likely to recur in children younger than 2 years than in others. ^[27]

Zalzal noted that, in any child with voice abnormalities before surgery, those abnormalities persisted after surgery. Subglottic pressure is required to produce a strong voice. If the narrowed subglottic airway is expanded, subglottic airflow and pressure increase, and the voice usually is stronger. See the images below.

Voice therapy may help relieve nonsevere glottic stenosis over time.

The voice of a patient with subglottic stenosis (SGS), especially those who require reconstruction, may never return to it preoperative state because the following are possible: (1) glottic stenosis, (2) imperfect closure of a laryngofissure through the anterior commissure, and (3) potential vocal cord weakness or tension caused by other laryngeal pathologic conditions. Since reconstructive techniques have improved over the last 20 years, the focus of attention in patients with subglottic stenosis (SGS) who require reconstruction has switched from decannulation to decannulation with improved voice outcome.

Controversies remain concerning the surgical techniques for mild-to-moderate subglottic stenosis (SGS). Options include endoscopic laser removal and dilation for mild subglottic stenosis (SGS) versus an open procedure. Most authors believe that, in children, scar excision with laser and dilation usually is unsuccessful in mature and severe subglottic stenosis (SGS). Many authors have reported the use of topical mitomycin applied to the area of laser excision of subglottic scar to improve the patency rate, as mentioned in the Surgical section. Mitomycin is proposed to help decrease scar formation by decreasing the cell division through its action on the microtubules in anaphase of mitosis. Despite the feeling that this antiproliferative agent is helpful, no consensus exists on its use.

The type of cartilage used for augmentation and reconstruction can be controversial as well. Some authorities believe that thinner cartilage (eg, auricular cartilage, thyroid ala) is satisfactory reconstructive material in certain situations. Most authorities recognize that costal cartilage provides the most support and that, in severe stenosis, weaker cartilage may be inadequate. The choice of cartilage often depends on the degree and location of the stenosis and on the postoperative care. Most airway reconstructive surgeons believe that posterior subglottic stenosis (SGS) requires lumen augmentation with firm cartilage. The selection of the anterior cartilage is not as critical, especially when stents are used after the procedure. In this setting, various authors have reported good success with superior strips of thyroid cartilage and auricular cartilage.

As with most diseases requiring surgical treatment, evaluations based on genetic predisposition and medical therapies to prevent the disease process that requires surgery are being evaluated. Novel ideas of expanding the airway, including the use of expandable and bioabsorbable airway stents, are being investigated. The role of growth factors and techniques to prevent wound healing are being evaluated as well. Unquestionably, any technique, device, or therapy that decreases the need for surgical intervention or donor cartilage decreases morbidity.