Laryngomalacia is the most common laryngeal anomaly and cause of stridor in newborns. Up to 20% of infants with laryngomalacia present with life-threatening disease that necessitates surgical management in the setting of severe airway obstruction and feeding disorders. Surgical correction of laryngomalacia has evolved over the past century from open tracheostomy to endoscopic modalities. This article provides a guide to patient assessment, surgical indication, operative technique, and perioperative management of patients with laryngomalacia. A review of surgical outcomes and complications is presented. Medical comorbidities often accompany patients with the least successful outcomes. Although complications are rare, they most commonly include persistent disease, supraglottic stenosis, and lower respiratory tract infections.
Laryngomalacia (LM) is the most common laryngeal anomaly and source of stridor (54–75%) in the newborn . Characterized by reduced laryngeal tone, shortened aryepiglottic folds, and supraglottic collapse, LM can lead to significant upper airway obstruction and feeding disturbances in infants afflicted by this disease. Most cases are mild and self limited, with resolution by age 12-24 months. Symptoms in these patients are generally managed with conservative and medical therapy . However, nearly 20% of infants with LM will present with severe disease requiring surgery to eliminate or bypass the obstruction. Surgical approaches have evolved, with endoscopic techniques discovered to be a successful and a safe alternative to tracheostomy . The terms “supraglottoplasty”, “epiglottoplasty”, and “aryepiglottoplasty,” have been applied to endoscopic approaches to treat LM that aim to trim the aryepiglottic folds and remove soft tissue, overriding the arytenoids . Surgical success approximates 94%, with minimal risk of recurrent symptoms or complication. However, specific populations may be prone to less favorable outcomes . Epiglottopexy, in which the epiglottis is surgically secured to the valeculla, has also been employed with varied success for specific types of LM .
Surgical history
In the mid-nineteenth century, the invention of the laryngeal mirror provided indirect access to observe the dynamic larynx . With this technique, infants with “congenital laryngeal stridor” were noted to obstruct their glottic inlet with collapsing supraglottic structures during inspiration. This was initially proposed to occur as the result of enlarged and compressing cervical structures. Several authors, including Reardon , Lees , Sutherland and Lack , and Variot suggested “congenital laryngeal stridor” to be an inherent abnormality of the supraglottic larynx. Variot was the first to suggest removal of excess aryepiglottic (AE) tissue for treatment in these infants. It was not until the 1920s, however, when surgical techniques to reduce supraglottic tissue were introduced in the literature. In particular, Inglauer reported symptom improvement in an infant with congenital stridor after partial epiglottectomy using a nasal snare. Six years later, Hasslinger described the endoscopic resection of AE folds in three infants using cupped forceps. Sporadic reports of supraglottic surgical intervention included epiglottic wedge resections , epiglottic-to-tongue-base adhesions , and hyomandibulopexy . Despite reported success, none of these techniques gained particular favor for routine use in the otolaryngologic community. During this period, most infants were managed with tracheostomy, whereas decannulation awaited resolution of obstructive symptoms. It was not until the 1980s that the concept of operating on the supraglottic larynx was reintroduced.
The term “laryngomalacia” was proposed by Jackson and Jackson in 1942 to describe patients previously labeled as having “congenital laryngeal stridor.” “Laryngomalacia” was designated to more accurately describe the flaccid laryngeal tissue and inward curling of surpraglottic structures that occur during inspiration and is not found in other sources of infantile stridor. This idiom was only used sporadically until the revitalization of endoscopic tools for diagnosing and treating infants occurred. Since the advent of the Hopkin’s rod, surgeons have learned to manipulate and cure many diseases of the upper airway. Along with the evolution and advancement of endoscopic laryngeal surgery came reconsideration of endoscopic techniques to surgically improve patients with LM as an alternative to tracheostomy. Several pioneers illustrated the supraglottic anomalies in LM, as others took the intellectual leap to treat them endoscopically .
In 1984, Lane and colleagues revisited the endoscopic approach to achieve symptom improvement in an infant with severe LM. They embellished Hasslinger’s original technique with the use of Bulluci scissors and microcup forceps to trim supra-arytenoid mucosa and incise the AE folds. Coinciding with the emerging popularity of carbon dioxide (CO 2 ) laser as a microscopic tool, this report was soon followed with an article by Seid and colleagues , which illustrated the use of CO 2 laser to divide the AE folds. The excellent surgical results from these two groups, and several others, paved the way for endoscopic interventions to correct severe LM . Zalzal and colleagues applied the term “epiglottoplasty” to describe trimming the lateral epiglottis along with the AE folds and supra-arytenoid tissue using microscissors. However, others feel that the term “supraglottoplasty” best describes the surgical manipulation of the supraglottic larynx in LM. With the development of new concepts and technology, endoscopic techniques are likely to evolve. Laryngeal microdebriders have been added to the arsenal with good results . A movement may be underway to return to microlaryngeal cold steel instrumentation to offset risks of airway fires, laryngeal edema, and postoperative feeding disturbances that can theoretically occur with the use of lasers .
Clinical presentation
Stridor is the hallmark of congenital LM. The reverberations of the juxtaposed prolapsing supraglottic tissue in the glottis during inspiration produce the fluttering quality of stridor heard. Although this is found in variants of LM that have been reported in older children, LM most frequently occurs in newborns . The typical presentation of congenital LM is high-pitched stridor with upper airway obstruction that worsens with agitation, crying, feeding, or the supine position. Symptoms begin within the first few weeks of life and peak near age 6 to 8 months. Most infants who have LM have mild symptoms that are benign and self-limited and resolve by 12 to 24 months . Expectant management is used. In these cases, obstructive symptoms are relieved by repositioning or extending the neck as this technique tenses and widens the larynx. Referral to an otolaryngologist for infants who have mild LM is often not warranted.
Feeding symptoms associated with the stridor of LM reflect the intimate relationship between the upper airway and digestive tract in newborns. Up to 80% of infants who have LM have gastroesophageal reflux disease (GERD) and laryngopharyngeal reflux (LPR) . Clinical manifestations include regurgitation, recurrent emesis, dysphagia, feeding intolerance, weight loss, and a “wet” cough that is temporally associated with meals . Coughing and choking during feeding are the most commonly reported feeding complaint in patients with moderate symptoms of LM . Frequent episodes of spitting up along with slow and laborious feeding also make feeding difficult in these patients.
Up to 10% to 20% percent of patients who have LM present with severe symptoms that warrant surgical intervention . In these patients, supraglottic prolapse leads to life-threatening airway obstruction or feeding disorders. Because metabolic demands are also elevated in these infants, as they try to coordinate eating with breathing against an obstructed larynx, patients with severe disease can lose weight and present with failure to thrive. Infants with perioral pallor and cyanosis, along with suprasternal and substernal retractions that may or may not occur during feeding, often require surgical intervention when conservative measures fail. Stridor with dyspnea, tachypnea, cyanosis, pectus excavatum, and sleep apnea are hallmarks of severe disease. Previous hospitalization for dyspnea in such patients is often reported. Young or premature infants can present with apnea but no audible stridor . Pulmonary hypertension, developmental delay, and cardiac failure are seen in neglected cases of severe disease.
Clinical presentation
Stridor is the hallmark of congenital LM. The reverberations of the juxtaposed prolapsing supraglottic tissue in the glottis during inspiration produce the fluttering quality of stridor heard. Although this is found in variants of LM that have been reported in older children, LM most frequently occurs in newborns . The typical presentation of congenital LM is high-pitched stridor with upper airway obstruction that worsens with agitation, crying, feeding, or the supine position. Symptoms begin within the first few weeks of life and peak near age 6 to 8 months. Most infants who have LM have mild symptoms that are benign and self-limited and resolve by 12 to 24 months . Expectant management is used. In these cases, obstructive symptoms are relieved by repositioning or extending the neck as this technique tenses and widens the larynx. Referral to an otolaryngologist for infants who have mild LM is often not warranted.
Feeding symptoms associated with the stridor of LM reflect the intimate relationship between the upper airway and digestive tract in newborns. Up to 80% of infants who have LM have gastroesophageal reflux disease (GERD) and laryngopharyngeal reflux (LPR) . Clinical manifestations include regurgitation, recurrent emesis, dysphagia, feeding intolerance, weight loss, and a “wet” cough that is temporally associated with meals . Coughing and choking during feeding are the most commonly reported feeding complaint in patients with moderate symptoms of LM . Frequent episodes of spitting up along with slow and laborious feeding also make feeding difficult in these patients.
Up to 10% to 20% percent of patients who have LM present with severe symptoms that warrant surgical intervention . In these patients, supraglottic prolapse leads to life-threatening airway obstruction or feeding disorders. Because metabolic demands are also elevated in these infants, as they try to coordinate eating with breathing against an obstructed larynx, patients with severe disease can lose weight and present with failure to thrive. Infants with perioral pallor and cyanosis, along with suprasternal and substernal retractions that may or may not occur during feeding, often require surgical intervention when conservative measures fail. Stridor with dyspnea, tachypnea, cyanosis, pectus excavatum, and sleep apnea are hallmarks of severe disease. Previous hospitalization for dyspnea in such patients is often reported. Young or premature infants can present with apnea but no audible stridor . Pulmonary hypertension, developmental delay, and cardiac failure are seen in neglected cases of severe disease.
Patient assessment
The role of the otolaryngologist in the management of infants who have LM is to differentiate infants who require surgical intervention from others who only need close monitoring. Because the quality of stridor can vary among patients with the same disease severity, surgical candidates are selected less on stridor intensity and extent of laryngeal collapse and more on the degree and sequelae of airway obstruction and feeding difficulties. Most infants who have LM have mild to moderate symptoms (80%–90%) and do not require surgical intervention . Inconsequential stridor, retractions, regurgitation, and intermittent feeding difficulties without weight loss are characteristic of these patients. Separating mild from moderate cases is the extent of regurgitation, feeding intolerance, airway compromise, and GERD. In particular, these symptoms are debilitating in moderate cases of LM, wherein stridor may not resolve with repositioning, regurgitation occurs with each feed, and symptoms last longer.
In the absence of progressive symptoms, medical and conservative therapy can still be used. Frequent assessment of weight helps determine if those with moderate LM develop failure to thrive as seen in severe disease. Initial symptom presentation can change with time and emphasizes the importance of frequent evaluations. For example, up to 30% of infants with mild disease develop feeding symptoms and benefit from GERD therapy and feeding modifications. Similarly, 27% of infants with moderate disease have progressive airway and feeding symptoms that ultimately warrant surgical intervention. Typically, this occurs at approximately 4 to 6 months of age and approximately 2 months from the time of diagnosis. GERD and LPR have been implicated in this process . A clinical algorithm and diagnostic approach to infants with LM are summarized in Fig. 1 and discussed in the following sections.
Flexible laryngoscopy
Although the diagnosis of LM is often suggested by clinical presentation, confirmation is best established in the awake patient by flexible laryngoscopy. No sedation is required, and the infant is positioned upright or semi-reclined in the lap of a caregiver with gentle restraint. The scope is passed through the nose, and simultaneous assessment for nasopharyngeal, pharyngeal, and other laryngeal anomalies is performed.
Laryngoscopic findings include prolapse of the arytenoid cartilages, supra-arytenoid mucosa, and accessory cartilages during inspiration ( Fig. 2 A, B). Shortened AE folds with lateral collapse and an “omega”-shaped or curled epiglottis are also characteristic. In severe cases, retroflexion of the epiglottis to the posterior pharynx can occur. One must remember that an “omega”-shaped epiglottis can be present in up to 50% of normal infants. A clear history and evidence of laryngeal collapse and obstruction must be demonstrated before the diagnosis of LM can be made .
Proposed classification schemes illustrate the various patterns of supraglottic collapse frequently encountered during laryngosocopy in patients who have LM ( Table 1 ) . Essentially, the larynx can prolapse at one or more locations of the supraglottis (ie, posterior, lateral, or anterior), which is best reflected in three previously proposed LM types . In the first, posterior redundant mucosa and accessory cartilages, overriding the arytenoid, fold anteriorly into the larynx on inspiration. This is reported to be the most common anomaly in several clinical series (>50% patients who have LM). The second type is characterized by shortened AE folds with lateral displacement into the larynx. The third is described as posterior displacement of the epiglottis over the glottic inlet. The pattern of collapse is unpredictable and may include more than one area of the supraglottis. A correlation with the site of obstruction and disease severity has not been illustrated; however, the location and degree of collapse may influence therapeutic decisions. The anatomic defect in each type can be addressed selectively. For example, arytenoid reduction can be performed for anterior displacement, AE fold incisions to lengthen these folds may be appropriate for lateral collapse, whereas epiglottopexy can correct posterior epiglottic collapse. The impact of patient selection has not been evaluated systematically. However, equivalent surgical success rates have been described in retrospective series when the surgical approach was based on the pattern of supraglottic collapse .
| Authors | Type | Location | Anatomic correlate | % |
|---|---|---|---|---|
| McSwiney, et al | — | Anterior | Long curled epiglottis with collapse posteriorly | — |
| — | Lateral | Short AE folds | — | |
| — | Posterior | Bulky arytenoids | — | |
| Holinger and Konier | A | Posterolateral a | Short AE folds and redundant supra-arytenoid soft tissue | — |
| B | Complete | Long, tubular curled epiglottis | — | |
| C | Anterior | Posterior displacement of epiglottis to posterior pharyngeal wall | — | |
| Roger, et al | — | Complete | Omega epiglottis, short AE folds, redundant supraglottic mucosa | 66 |
| — | Predominately posterior | Redundant supra-arytenoid tissue | 32 | |
| — | Isolated anterior | Epiglottic posterior swaying | 2 | |
| Olney, et al | 1 | Posterior a | Prolapse of mucosa over arytenoids | 57 |
| 2 | Lateral | Foreshorten AE folds | 15 | |
| 3 | Anterior | Posterior displacement of the epiglottis | 13 | |
| Combined | All | Collapse of poster, anterior and lateral structures | 15 | |
| Kay and Goldsmith | — | Foreshortened AE folds a | Short AE folds | — |
| — | Surpraglottic soft tissue | Redundant cuneiform/corniculate cartilage and mucosa | — | |
| — | Neuromuscular disorders | — | ||
| Lee, et al | Group I | A only a b | See Hollinger type | 54 |
| Group II | B, or B+A b | 22 | ||
| Group III | C, C+A, C+B+A b | 24 |
Patients who have neuromuscular disorders seem to have a higher incidence of epiglottic or complete supraglottic prolapse with increased clinical severity. A retroflexed epiglottis also may indicate pharyngomalacia or a coexisting vallecular cyst. These sites should be examined closely during flexible laryngoscopy in the setting of posterior epiglottic displacement .
A simple feeding assessment also can be used during flexible laryngoscopy. During the examination, the infant is allowed to feed from a bottle; the presence of laryngeal vestibular penetration or aspiration beyond the true vocal cords can be examined. These important and predictive findings can guide therapeutic decisions in some patients. Patients with mild symptoms and frequent episodes of laryngeal penetration or aspiration have been shown to progress to moderate disease and benefit from feeding modification and reflux therapy. Patients with moderate symptoms and demonstrate laryngeal penetration or aspiration can later develop worsening feeding issues and failure to thrive, thereby changing their candidacy for surgical intervention.
Airway films and airway fluoroscopy
Although high kilovoltage anteroposterior and lateral airway films are rarely necessary for diagnosis of LM, they can provide the clinician with important information on synchronous airway anomalies and pulmonary issues that can further compromise respiration. Airway fluoroscopy may be used to diagnose concurrent tracheomalacia. Fluoroscopy also illustrates hypopharyngeal dilation on inspiration and dynamic collapse of the supraglottis. More than 20% of infants who have LM are reported to have a synchronous airway lesion . Identification of concurrent airway lesions is important because they increase airway obstruction, enhance negative intrathoracic pressure gradients, and potentiate GERD. The presence of a synchronous airway lesion may contribute to symptom progression and surgical failures.
Microlaryngoscopy and rigid bronchoscopy
Most cases of LM are diagnosed by awake flexible laryngoscopy. Intraoperative rigid or flexible laryngoscopy and bronchoscopy aid in the diagnosis of LM and often are reserved for patients with moderate to severe symptoms in whom endoscopic intervention is considered. It is performed under light sedation and often under spontaneous respiration to examine the dynamics of the large airways. The added benefit of direct endoscopy is the opportunity to explore for synchronous large airway lesions, such as tracheomalacia, laryngotracheal stenosis, and bronchomalacia . Clear examination for laryngeal clefts also can be performed because they often mimic the signs and symptoms of LM . Intraoperative examinations should be conducted in patients in whom the diagnosis is difficult, patients with multiple congenital anomalies in whom concomitant airway disorders may be present, and patients with atypical symptoms. With rigid and flexible techniques, it is crucial to assess vocal cord mobility. Paralysis can be overlooked because of profound supraglottic prolapse eluding good examination of the vocal cords. This is important because surgical success of supraglottoplasty can be dramatically impacted by a missed vocal cord paralysis.
Complementary studies
The decision to obtain additional studies in infants who have LM is to maximize the management of the child with moderate or severe disease. These studies are particularly important in children who have multiple medical comorbidities, a syndrome, or a genetic disorder because they are at higher risk for supraglottoplasty failure . Congenital cardiac anomalies (7%) and neuromuscular disorders (10%–50%) have been shown to coexist in patients who have severe LM, and steps to aid in the diagnosis and management of these processes should be explored.
An esophagram is useful in assessing reflux and aspiration and concomitant gastrointestinal disorders if a contrast follow through is performed. Ruling out a concomitant gastrointestinal disorder, such as malrotation or pyloric stenosis, is particularly important in infants with recurrent emesis. Videofluoroscopic swallow study or a functional endoscopic evaluation of swallow allows for an assessment of feeding problems, laryngeal penetration, and aspiration. Any child with significant aspiration should undergo a chest radiograph to assess pulmonary injury. Chronic aspiration often results from a discoordinate suck-swallow-breath sequence in children with LM. It can complicate respiratory problems and prompt the clinician to perform supraglottoplasty sooner.
The role of 24-hour pH testing or impedance probe testing in infants who have LM has not been standardized. Twenty-four–hour pH studies in patients who have LM document the presence of GERD and LPR . In patients with recalcitrant disease, a pH probe or impedance study should be performed with anticipation of consulting a pediatric surgeon for a Nissen fundoplication. This procedure may be warranted before or after supraglottoplasty in a small percentage of patients because GERD can contribute to and be the result of severe LM. It is also indicated in patients who continue to have severe reflux after supraglottoplasty, whereby the induced reflux should be theoretically reversed.
The role of polysomnography has not been standardized in infants who have LM. The authors use this test in three specific circumstances. In infants who develop signs, symptoms, and findings consistent with pulmonary hypertension or cor pulmonale, pre- and postoperative sleep studies are obtained to determine if the degree of hypoxia and hypercarbia has appropriately reversed after surgical intervention. For infants who have severe LM and medical comorbidities, such as a neurologic disorder, syndrome, or a genetic condition, a polysomnogram can aid in deciding whether to proceed with supraglottoplasty or tracheotomy. In infants who have obstructive symptoms that seem disproportionate to clinical examination findings, an abnormal sleep study helps to determine if surgical intervention is indicated.
An echocardiogram is indicated in any infant who has a history of congenital heart disease. This study helps the involved clinicians determine if hypoxia is airway related, of cardiac origin, or both. If a child has congenital heart disease, the echocardiogram also provides realistic expectation of an expected level of hypoxia that the child may tolerate after surgical intervention. The authors’ experience is that infants who have significant congenital heart disease, hypoxia, and LM have a high risk of failing supraglottoplasty and often require tracheotomy. An echocardiogram should be considered in infants who have a syndrome and multiple levels of airway obstruction. It is likely that these infants have more severe airway obstruction than expected. Detecting pulmonary hypertension could prevent further complications.
Evaluation of children with late-onset variant laryngomalacia
Recent reports of adolescent and adults patients with “acquired” and “exercise-induced” LM suggest that this is not just a disease of early childhood . Similarly, “state-dependent” LM has been reported in infants and toddlers who present with sleep-induced stridor, upper airway obstruction, and apnea . Classic symptoms and laryngeal findings of congenital LM are often absent in these patients. LM also has been identified as the cause of feeding difficulties in toddlers. The origin of the disease is unclear in these older patients who have no prior history of diagnosis of LM as an infant. Although symptoms differ for each group, the site of obstruction at the supra-arytenoid level is common in late-onset and acquired groups of LM. Evaluating the child and establishing the diagnosis of late-onset variant LM is not straightforward because these children do not always present with the hallmark symptom of stridor. Flexible laryngoscopy during exercise aids in the diagnosis of the child with exercise-induced LM. Polysomnograms should be considered in adolescent children with sleep apnea, whereas feeding disorders in toddlers can be evaluated for LM using functional endoscopic evaluation of swallow or videofluoroscopy . Diagnosis of these atypical cases may be augmented by analysis of flow-volume loops at tidal breathing that reveal inspiratory flutter and restricted inspiratory volume in LM . Supra-arytenoid tissue leads to symptom resolution in most cases .
Empiric reflux therapy and feeding modifications
Because up to 80% of infants who have LM have GERD or LPR, any infants with symptoms of coughing and choking, regurgitation, or feeding difficulty should be considered candidates for medical management with empiric acid reflux suppression .
The proposed pathophysiology of the deleterious effects of acid reflux in patients who have LM is a result of the large negative intrathoracic pressure gradients generated during breathing against a fixed obstruction. The pressure gradient change promotes the reflux of stomach contents into the esophagus and upper airway . Gastric acid exposure, particularly in the supra-arytenoid mucosa and AE fold regions, causes excessive localized laryngeal tissue edema. The resultant redundant edematous tissue prolapses into the airway during inspiration and leads to airway obstruction, which can lead to a vicious cycle of more obstruction, worsening GERD, and increased edema . Central and efferent vagal functions responsible for laryngeal tone are simultaneously responsible for lower esophageal sphincter tone and esophageal motility . Disruption of neural signaling, as suspected in the LM larynx, can affect esophageal motility and lower esophageal tone. This results is transient events of lower esophageal relaxation, reflux of acid, and laryngeal penetration .
Assessing an infant’s response to medical intervention may help determine which infants can be watched carefully and which require intervention. The authors have used two different strategies with success: H 2 receptor antagonist (H 2 RA) therapy (ranitidine, 3 mg/kg three times a day) or proton pump inhibitor (PPI) therapy (1 mg/kg daily). Infants who have worsening of symptoms on either therapy are started on H 2 RA therapy (ranitidine, 6 mg/kg at night) and PPI therapy (1 mg/kg daily). Parental perception suggests that GERD improves the symptoms in most infants. Moderate cases of LM have a greater incidence of GERD and require longer treatment courses until symptoms resolution .
Symptoms of recurrent coughing and choking during feeding and signs of cyanosis or worsening of airway obstruction in infants suggest that laryngeal penetration or aspiration is occurring. These infants are often helped by feeding modifications and acid suppression therapy. Feeding modifications include pacing, texture change by thickening the formula, and upright feeding position. Confirmation of laryngeal penetration or aspiration can be documented by endoscopic swallow study or videofluoroscopic swallow study. Any infant who develops signs and symptoms of failure to thrive or worsening of airway obstruction after acid suppression therapy and feeding modifications is considered a candidate for surgical intervention.
Surgical indications
Infants with severe disease are candidates for surgical intervention. Supraglottoplasty is the primary operation used with tracheotomy reserved for supraglottoplasty failures or infants with multiple medical comorbidities that warrant tracheotomy placement for additional reasons besides airway obstruction. Suggested absolute and relative indications for supraglottoplasty are listed in Table 2 .
