Laryngomalacia: an atypical case and review of the literature.
Laryngomalacia is the most common cause of stridor Stridor Definition
Stridor is a term used to describe noisy breathing in general, and to refer specifically to a high-pitched crowing sound associated with croup, respiratory infection, and airway obstruction. in newborns and infants. Patients usually present with an inspiratory stridor only, although some exhibit other anomalies. To rule out other possible pathologies, bronchoscopy Bronchoscopy Definition
Bronchoscopy is a procedure in which a cylindrical fiberoptic scope is inserted into the airways. This scope contains a viewing device that allows the visual examination of the lower airways. is advisable. However, the authors of some recent studies have advocated the use of fiberoptic laryngoscopy as a more cost-effective and less-invasive alternative. No surgical intervention is required to treat laryngomalacia in most cases. The disease usually resolves spontaneously by the time a patient reaches the age of 24 months. In this article, we describe a case of laryngomalacia that was atypical in that the patient was 10 years old. We also review the literature in an effort to increase awareness of this condition.
Laryngomalacia is the most common congenital malformation of the larynx, and it is the most common cause of stridor in newborns and infants. (1) It manifests as an inspiratory stridor and is usually characterized by a highpitched, fluttering voice. (2) Although affected patients do not exhibit much in the way of other physical symptoms, the unusual voice is worrisome to their parents. The stridor usually worsens during the first 8 months of life, reaches a plateau at 9 to 12 months, and generally resolves gradually by the rime the patient reaches 24 months of age. (3)
No intervention is necessary for most patients. Surgery is required only when there are signs of failure to thrive Failure to Thrive Definition
Failure to thrive (FTT) is used to describe a delay in a child's growth or development. It is usually applied to infants and children up to two years of age who do not gain or maintain weight as they should. , obstructive sleep apnea Obstructive sleep apnea (OSA)
A potentially life-threatening condition characterized by episodes of breathing cessation during sleep alternating with snoring or disordered breathing. , cor pulmonale, severe reflux, or apnea while awake or when the disease does not spontaneously resolve as anticipated. Persistence beyond 24 months is rare, but a few case reports have been documented, some of which occurred as late as adolescence. (4,5)
In this article, we describe an unusual presentation of laryngomalacia, and we review the literature in an attempt to increase physician awareness of this disease.
A 10-year-old boy was brought to the ENT ENT ears, nose, and throat (otorhinolaryngology).
ear, nose, and throat
ear, nose and throat.
ENT Ears, nose & throat; formally, otorhinolaryngology clinic at The Aga Khan University Hospital Aga Khan University Hospital may refer to:
n. syrup and advised the boy's parents that the stridor would persist until the boy reached 2 years of age. The antibiotic syrup failed to improve the patient's condition.
When the patient was 3 years old, he was taken to a local hospital, where he was given a provisional diagnosis of laryngomalacia and prescribed terbutaline terbutaline /ter·bu·ta·line/ (ter-bu´tah-len) a ß agonist; used as the sulfate salt as a bronchodilator and as a tocolytic in the prevention of premature labor. syrup. Physicians there suggested that he undergo direct bronchoscopy, and they referred him to AKUH. However, the parents could not afford to pay for the bronchoscopy, and they did not follow up on the recommendation. The boy did show some improvement with the terbutaline.
During our evaluation, we learned that the patient had been born at term and at home; the delivery was uncomplicated. Although his birth weight and other anthropometric an·thro·pom·e·try
The study of human body measurement for use in anthropological classification and comparison.
an parameters at the time of his birth were not known, he appeared to be healthy. His mother had not been exposed to medicines or teratogens teratogens, (trat´ōjens),
n.pl agents that cause congenital malformations and developmental abnormalities if introduced during gestation. during her pregnancy. The boy's parents were healthy and not consanguineous con·san·guin·e·ous
consanguineous adjective Referring to a blood relationship–ie, descendent from a common ancestor . He grew normally and achieved appropriate developmental milestones. He began speaking one-syllable letters at 12 months of age and brief sentences at 2 years. He was sociable and exhibited no behavioral problems.
This time, bronchoscopy was performed at AKUH, and it revealed that the patient had an omega-shaped epiglottis epiglottis (ĕp'əglŏt`ĭs): see larynx. but no other obvious physical abnormality in the airway. However, during inspiration, the airway was seen to collapse, and flabby flab·by
adj. flab·bi·er, flab·bi·est
1. Lacking firmness; flaccid: getting flabby around the waist. See Synonyms at limp.
2. aryepiglottic folds were sucked in. Based on these findings, the diagnosis of laryngomalacia was confirmed.
The patient was discharged with an assurance that his condition was self-limited and would resolve in time. No change in his symptoms was noted on the first follow-up 1 week later. One year later, the frequency of his inspiratory stridor had markedly decreased, and it occurred only on strenuous exertion. Otherwise, the child was living a normal life.
Congenital stridor was reported as early as 1853 by two French physicians, Rilliet and Barthez. (6) They described a newborn who had both inspiratory in·spi·ra·to·ry
Of, relating to, or used for the drawing in of air.
pertaining to or used in the inspiration of air into the lungs. and expiratory stridor; the child was otherwise normal. The first comprehensive review of this condition was published by Sutherland and Lack in 1897. (7) In their article, entitled "Congenital laryngeal laryngeal /lar·yn·ge·al/ (lah-rin´je-al) pertaining to the larynx.
la·ryn·geal or la·ryn·gal
Of, relating to, affecting, or near the larynx. obstruction," they described a series of 18 patients with laryngomalacia, which they called congenital laryngeal stridor. In 1942, Jackson was the first to use the term laryngomalacia (from the Greek malakia: morbid softening of part of an organ); he defined it as a softness, flabbiness flab·by
adj. flab·bi·er, flab·bi·est
1. Lacking firmness; flaccid: getting flabby around the waist. See Synonyms at limp.
2. , or loss of consistency of laryngeal tissues. (8)
In affected patients, inspiratory stridor is usually present at birth, although in some cases it does not become apparent until weeks or months later. In some infants, the stridor does not manifest until the child becomes more active at approximately 3 months of age; in other cases, the stridor is precipitated by an upper respiratory infection Noun 1. upper respiratory infection - infection of the upper respiratory tract
respiratory infection, respiratory tract infection - any infection of the respiratory tract . (9) Sometimes vibrations can be felt by placing a hand on the infant's chest. Parents have described the stridor as purring purring
a physiologically very complicated, semi-automatic, cyclic, controlled respiration involving alternating activity of the diaphragm and intrinsic laryngeal muscles in cats. The frequency of the alternation is about 25 times per second. , crackling, crowing, croaking, and squeaking. Affected infants are neither dyspneic nor generally uncomfortable. However, in 10% of cases, the upper airway obstruction is severe enough to cause apnea or failure to thrive, which necessitates surgical intervention. (10)
The stridor is often intermittent; it is exacerbated when the child is active and crying. (4,7) It can be aggravated by upper respiratory tract infections, which increase the risk of aspiration. The severity of the stridor can be affected by body position--that is, it is aggravated by supination supination /su·pi·na·tion/ (soo?pi-na´shun) [L. supinatio ] the act of assuming the supine position, or the state of being supine. and head flexion flexion /flex·ion/ (flek´shun) the act of bending or the condition of being bent.
1. The act of bending a joint or limb in the body by the action of flexors.
2. and is relieved by pronation pronation /pro·na·tion/ (-na´shun) the act of assuming the prone position, or the state of being prone. Applied to the hand, the act of turning the palm backward (posteriorly) or downward, performed by medial rotation of the forearm. and head extension. (7,11) Some cases have been reported in which the condition was severe enough to cause intercostal intercostal /in·ter·cos·tal/ (-kos´t'l) between two ribs.
Located or occurring between the ribs.
A space, muscle, or part situated between the ribs. , abdominal, supraclavicular, infraclavicular, and xiphoid xiphoid /xiph·oid/ (zif´oid) (zi´foid)
1. ensiform; sword-shaped.
2. xiphoid process.
Sword-shaped. retractions, which can lead to pectus excavatum. (12,13) Cyanosis cyanosis (sī'ənō`sĭs), bluish coloration of the skin, mucous membranes, and nailbeds, resulting from a lack of oxygenated hemoglobin in the blood. is rare. (9,14) Reports of stridor during sleep are variable. (4,9, 11)
Etiology. The etiology of laryngomalacia remains unknown. Four primary causes have been theorized over the years: (1) cartilage immaturity, (2) an anatomic abnormality, (3) neuromuscular immaturity, and (4) the presence of gastroesophageal reflux disease gastroesophageal reflux disease (GERD)
Disorder characterized by frequent passage of gastric contents from the stomach back into the esophagus. Symptoms of GERD may include heartburn, coughing, frequent clearing of the throat, and difficulty in swallowing. (GERD GERD gastroesophageal reflux disease.
gastroesophageal reflux disease
Cartilage immaturity. In the late 19th century, Sutherland and Lack proposed that laryngomalacia is related to a delay in the normal development of cartilaginous cartilaginous /car·ti·lag·i·nous/ (kahr?ti-laj´i-nus) consisting of or of the nature of cartilage.
2. support of the arytenoids and epiglottic epiglottic
pertaining to or emanating from the epiglottis.
attached to the thyroid cartilage of the larynx by the thyroepiglottic ligament; it is the structural basis of the epiglottis. tissues. (7) Since then, this theory has been disproved. Chandra et al showed that laryngomalacia does not represent a histologically identifiable chondropathy and that cartilaginous abnormalities play no role in its pathogenesis. (15) Moreover, the literature reveals that infants even 2 or 3 months immature are no more likely to experience laryngomalacia than are term infants.
Anatomic abnormality. In 1922, Iglauer proposed that laryngomalacia is the result of an exaggeration of the infantile larynx. (12) The laryngeal tissues of infants are relatively soft and flaccid flaccid /flac·cid/ (flak´sid) (flas´id)
1. weak, lax, and soft.
Lacking firmness, resilience, or muscle tone. and their aryepiglottic folds and arytenoid arytenoid /ar·y·te·noid/ (ar?i-te´noid) shaped like a jug or pitcher, as arytenoid cartilage.
1. tissues are relatively large; as a result, their glottic glot·tic
1. Of or relating to the tongue.
2. Of or relating to the glottis.
pertaining to (1) the glottis, or (2) the tongue. opening is smaller and their larynx is flabbier and softer. The elongated e·lon·gate
tr. & intr.v. e·lon·gat·ed, e·lon·gat·ing, e·lon·gates
To make or grow longer.
adj. or elongated
1. Made longer; extended.
2. Having more length than width; slender. , tubular epiglottis and closely approximated aryepiglottic folds are drawn inward on inspiration because the supporting framework is too pliable. The folded epiglottis acquires an "omega" or tubular shape. As the child grows older, the tissues become resistant to inspiratory forces. This theory is supported by several findings that have led endoscopists to describe the larynx of children with laryngomalacia as infantile. (16) But omega- and tube-shaped epiglottises exist in nonstridorous infants as well, indicating that they are not an important factor in causing laryngomalacia.
Neuromuscular immaturity. There is a high prevalence of neurologic disorders in patients with laryngomalacia, which has led some investigators to believe that laryngomalacia is caused by neuromuscular immaturity and consequent laryngeal hypotonia hypotonia /hy·po·to·nia/ (-ton´e-ah) diminished tone of the skeletal muscles.
1. Reduced tension or pressure, as of the intraocular fluid in the eyeball.
2. . However, this theory needs further investigation. (16,17)
GERD. At one time, it was believed that GERD occurred in 35 to 68% of infants with laryngomalacia. (18,19) However, in 1999, Matthews et al, using double-probe pH testing, reported that GERD was present in almost 100% of cases of laryngomalacia. (20) Despite attempts to identify the mechanism, no link between GERD and stridor has been confirmed. It is not certain whether GERD causes airway symptoms or vice versa. Orenstein and Orenstein proposed that reflux of gastric contents causes supraglottic edema edema (ĭdē`mə), abnormal accumulation of fluid in the body tissues or in the body cavities causing swelling or distention of the affected parts. and changes airway resistance, thereby causing airway obstruction. (21) On the other hand, Wang et al speculated that the
increased negative intrathoracic pressure during inspiration in an obstructed laryngeal airway could predispose pre·dis·pose
To make susceptible, as to a disease. a patient to GERD by trying to overcome the lower esophageal sphincter lower esophageal sphincter
A ring of smooth muscle fibers at the junction of the esophagus and stomach. Also called cardiac sphincter. . (22) Nevertheless, surgical treatment of GERD often fails to relieve respiratory symptoms. (23) Hadfield et al recently showed that treating laryngomalacia by aryepiglottoplasty alleviated GERD, suggesting that laryngomalacia plays a causative role in GERD. (24)
Various mechanisms have been proposed as the cause of airway obstruction, but six deserve mention. (25) They include (1) the inward collapse of the aryepiglottic folds, primarily the cuneiform cartilages, (2) an elongated epiglottis curled on an abnormality, (3) anterior and medial collapsing movements of the arytenoid cartilages, (4) posterior and inferior displacement of the epiglottis, (5) short aryepiglottic folds, and (6) an overly acute angle of the epiglottis.
A possible familial predisposition was first noted in 1953 by Apley, who found stridor in 15 children from five families. (26) Later, Kahn et al found a positive family history in 3 patients. (27) Shulman et al described a family in which 3 of 5 siblings had laryngomalacia. (28) Shohat et al described an autosomal-dominant pattern of inheritance in a family in which 9 members of three generations were affected. (29) Harreus and Issing reported the case of an 8-month-old girl who presented with both laryngomalacia and a combined hearing loss; in this case, there was a deletion of the long arm of chromosome 5q. (30) E1-Shanti et al found a new syndrome in 5 patients from two separate families who had laryngomalacia, XY gonadal dysgenesis, and alopecia universalis congenita. (31) However, the results of other studies (9,32) have not supported a familial relationship, and no genetic studies of laryngomalacia have been reported.
Endoscopic investigations. Laryngomalacia occurs both in isolation and in association with other anomalies of the airway or other organ systems. Synchronous airway lesions have been reported in 19% of affected infants. (33) Some investigators believe that the presence of other secondary airway lesions in all infants with laryngomalacia mandates direct laryngoscopy and bronchoscopy in order to avoid the risk of missing a potentially life-threatening secondary airway lesion. (34) Because these procedures require general anesthesia, the risk of associated morbidity and mortality Morbidity and Mortality can refer to:
According to Botma et al, a better alternative as a firstline investigation in children with stridor is fiberoptic laryngoscopy; they recommend that bronchoscopy be reserved for those patients who are likely to have a pathology other than laryngomalacia and for those who fail to thrive. (35) Fiberoptic laryngoscopy is safe and costeffective; in fact, it is 100 times less expensive than direct bronchoscopy. Fiberoptic laryngoscopy was first used to investigate stridor in infants by Silberman et al in the 1970s. (37) In 2000, Botma et al reported the results of their investigation of the role of fiberoptic laryngoscopy in 43 infants with stridor. (35) Of this population, 35 were diagnosed with laryngomalacia, 6 had vocal fold palsies, and 2 were normal. These findings indicate that fiberoptic laryngoscopy is fairly sensitive in diagnosing laryngomalacia.
Surgery. Surgical intervention is not required for most patients in whom laryngomalacia is self-limited because most mature normally. If the child's general progress is satisfactory, active management is not necessary, and parents can be reassured that the symptoms will subside over time. Surgery is required only in severe cases--those that involve the collapse of the glottis glottis /glot·tis/ (glot´is) pl. glot´tides [Gr.] the vocal apparatus of the larynx, consisting of the true vocal cords and the opening between them.glot´tal
n. pl. on inspiration and the presence of complications of obstruction (e.g., failure to thrive, obstructive sleep apnea, cor pulmonale, severe reflux, or apnea while awake).
Iglauer was first to perform surgery on a patient with laryngomalacia (he amputated the epiglottis with a wire snare), a case that he reported in 1922. (12) Endoscopic surgery was first reported in 1984 by Lane et al, who noted that it led to a dramatic improvement in a 3-month-old patient; they excised the lateral portions of the epiglottis, the corniculate cartilage, and the tips of the arytenoids. (3)
Use of a C[O.sub.2] laser was first reported by Seid et al in 1985; they divided the aryepiglottic fold with the laser in 2 patients. (38) Since then, various surgical modifications have been developed. Surgeries today are usually performed with a C[O.sub.2] laser and microdissection. The procedures that have been advocated include (1) division of the aryepiglottic fold, (2) partial amputation amputation (ăm'pyətā`shən), removal of all or part of a limb or other body part. Although amputation has been practiced for centuries, the development of sophisticated techniques for treatment and prevention of infection has greatly of the epiglottis, (3) suture of the epiglottis to the base of the tongue (epiglottoplasty), (4) removal of redundant supra-arytenoid mucosa and the lateral borders of the epiglottis, and (5) removal of the cuneiform cuneiform (kynē`ĭfôrm) [Lat.,=wedge-shaped], system of writing developed before the last centuries of the 4th millennium B.C. and corniculate cartilages and the surrounding mucosa. In extreme cases, tracheostomy is performed.
Kelly and Gray (39) and Reddy and Matt (40) reviewed the complications of surgical procedures for laryngomalacia and compared the outcomes of patients who underwent unilateral and bilateral supraglottoplasty. They recommended the unilateral procedure as the first-line surgical treatment of severe laryngomalacia that requires surgery.
The authors thank Shaikh Rahmatullah, a secretary in the Otolaryngology--Head and Neck Surgery unit at The Aga Khan University, for his cooperation and clerical help in the preparation of the manuscript.
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Clearance granted to a ship to proceed into port after compliance with health regulations or quarantine.
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From the Department of Surgery (Dr. Awan) and the Department of Biological and Biomedical Sciences (Mr. Saleheen), The Aga Khan University, Karachi, Pakistan; and the Department of ENT, the Fauji Foundation Hospital, Rawalpindi, Pakistan (Dr. Ahmad).
Reprint requests: Dr. Sohail Awan, Otolaryngology--Head and Neck Surgery, Department of Surgery, The Aga Khan University Hospital, Stadium Rd., Karachi 74800, Pakistan. Phone: 92-21-48594769; fax: 92-21-493-4294 or 92-21-493-2095; e-mail: email@example.com