Congenital lesions of larynx

Congenital lesions of the larynx

1. Supraglottis – Laryngomalacia (congenital laryngeal stridor), Saccular cyst.
2. Glottis – Congenital vocal cord paralysis, Laryngeal web. 
3. Subglottis – Congenital subglottic stenosis, Subglottic haemangioma, Laryngo-oesophageal cleft.

1. Laryngomalacia (congenital laryngeal stridor). Laryngomalacia emerges as the most prevalent congenital anomaly of the larynx, causing stridor, typically manifesting days to weeks after birth. Infants with this condition develop intermittent inspiratory stridor due to a floppy supraglottis that collapses during inhalation, leading to partial or complete obstruction of the airway. Furthermore, this self-limiting disorder resolves naturally as the larynx matures, with symptoms often diminishing by age 2 years. Additionally, you will observe high-pitched stridor that intensifies during crying or when the infant lies supine, but improves when the baby is placed prone. Moreover, the vocal cords remain unaffected, preserving a normal cry, which aids in differentiating this condition.

Aetiology and Risk Factors

The condition is most likely caused by immature neuromuscular control rather than structural laryngeal weakness. Many affected infants experience acid reflux, though its precise contribution remains under investigation.

Clinical Presentation

Inspiratory stridor, peaking around 6-9 months and resolving by age 2 years, improves when you place the infant in a prone position and most cases present within the first 4 months of life, requiring your keen observation.

Furthermore, feeding difficulties – such as coughing, choking, regurgitation, and poor weight gain—frequently accompany this disorder. Additionally, severe instances may lead to failure to thrive or chronic hypoxia, potentially causing pulmonary hypertension.

Diagnostic Approach

• During physical examinations, there may be tachypnoea, cyanosis, pectus excavatum, chest retractions, and obstructive sleep apnoea in affected infants.
• Flexible laryngoscopy reveals distinctive features: a long and curled (omega-shaped) epiglottis, floppy and shortened aryepiglottic folds, and redundant supraglottic tissue collapsing during inspiration, producing stridor.

Management. You should consider active management for laryngomalacia in patients exhibiting severe stridor or failure to thrive.

• For mild cases, reassurance and regular monitoring, noting that most infants outgrow the condition by age 2 years. No active intervention is required.
• Reflux management becomes essential for infants with feeding issues, choking, or regurgitation, especially with a 4-week antacid course for those diagnosed with regurgitation and gastro-oesophageal reflux disease.
• Surgical intervention becomes necessary when oxygen saturation drops to ≤91%, failure to thrive persists, or recurrent pneumonia from aspiration occurs.

Surgical Interventions. Surgical intervention becomes necessary when oxygen saturation drops to ≤91%, failure to thrive persists, or recurrent pneumonia from aspiration occurs.

• Supraglottoplasty (aryepiglottoplasty) to trim excess arytenoid mucosa using lasers or cold instruments, effectively alleviating severe symptoms.
• Tracheostomy serves as a rare option, reserved for life-threatening airway obstructions. Consequently, applying these techniques enhances your ability to restore normal breathing and support healthy development in affected infants.

2. Laryngeal cyst. Laryngeal cysts are rare but clinically significant causes of airway obstruction in infants and young children. These lesions may be congenital or acquired. Despite both originating from the laryngeal ventricle, they exhibit distinct anatomical and pathological features. The laryngeal ventricle lies between the true vocal cord below and the false vocal fold above. Its anterior extension, the saccule, functions in mucus secretion.

Laryngeal cysts include two primary types: laryngoceles and saccular cysts.

• Laryngocoele. A laryngocele represents an air-filled expansion of this ventricle that communicates directly with the laryngeal lumen. Though typically found in adults, laryngoceles can appear in infancy, where they may cause intermittent respiratory distress, especially during crying. If secondarily infected or filled with mucus, the lesion becomes a laryngopyocele, which clinically mimics a saccular cyst.
• Saccular cyst (Laryngeal cyst). In contrast, a saccular cyst contains mucus and lacks communication with the laryngeal lumen. It arises due to developmental failure to maintain the patency between the saccule and ventricle. Anatomically, saccular cysts may be anterior, displacing the airway medially and posteriorly, or lateral, extending into the false vocal fold and aryepiglottic fold. The lateral type predominates in infancy.

Laryngeal cysts are further classified as type 1 (internal) when confined within the larynx or type 2 (external) if they penetrate the thyrohyoid membrane.

Diagnosis:

• Laryngoscopy shows an enlarged and smooth swelling in the region of the false vocal cord and aryepiglottic fold.
• CT/MRI to assess the extent, and may be necessary for external lesions.

Treatment prioritises airway protection and definitive lesion removal.

• Endoscopic uncapping or marsupialisation remains the first-line therapy for saccular cysts.
• However, recurrent or extensive lesions often require external surgical excision via a lateral cervical approach. This method allows complete removal through a subperichondrial window in the thyroid cartilage.
• Short-term intubation is advised postoperatively to maintain airway stability.

3. Congenital vocal cord paralysis. This is the second most frequent congenital laryngeal anomaly, causing neonatal stridor. Clinically, it presents as either unilateral or bilateral in nearly equal proportions.

Aetiology

• Unilateral paralysis often arises from surgical trauma to the recurrent laryngeal nerve, particularly following forceps delivery, intubation, CTVS surgery, and repair of tracheoesophageal fistula.
• In contrast, more than half of bilateral cases are idiopathic. Bilateral paralysis is frequently linked to central nervous system anomalies, especially Arnold-Chiari malformation associated with hydrocephalus.

Symptoms

• Unilateral paralysis patients present with mild stridor, dysphonia and sometimes aspiration.
• Bilateral vocal cord palsy is usually a congenital abductor paralysis. The vocal cords lie in the paramedian position with consequent inspiratory stridor, and a tracheostomy is necessary in approximately half of the cases.

Management. It varies depending on the severity and laterality.

• In cases where the airway is compromised, a tracheostomy is essential.
• Unilateral paralysis may be monitored conservatively if the vocal cord is in an intermediate position; however, if the cord lies abducted, surgical intervention, such as thyroplasty, is indicated.
• Bilateral paralysis. Spontaneous recovery occurs in approximately 58% of cases. of congenital bilateral cases. If the recovery does not occur, definitive airway surgeries such as endoscopic laser cordotomy or arytenoidectomy may be considered after the age of 11 years. If the vocal cords are in paramedian position, it often demands tracheostomy.

4. Laryngeal web. A laryngeal web arises from incomplete recanalisation of the larynx during embryonic development. This congenital anomaly typically affects the anterior glottis, although rare cases involve the supraglottic or posterior interarytenoid region. The web progressively thickens anteriorly and thins near its posterior margins and often appears concave. Typically, the web forms between the vocal cords, partially fusing them and causing variable degrees of airway obstruction and dysphonia, depending on its thickness and extent.

Clinical features – Airway obstruction, aphonia, or a weak cry from birth. In addition, recurrent croup in infancy should raise clinical suspicion. As the child grows, caregivers may notice persistent respiratory symptoms or vocal limitations.

Diagnosis. Early diagnosis relies on a combination of clinical suspicion and direct visualisation using endoscopy. The condition’s management hinges on the web’s thickness, location, and associated airway anomalies.

Treatment depends on the thickness of the web.

• In mild cases, conservative observation suffices.
• Thin webs without subglottic involvement respond well to endoscopic division using a CO₂ laser or microsurgical knife, followed by dilatation to prevent recurrence.
• Thicker webs often require a silicone keel after division and may necessitate a temporary tracheostomy in infants.
• When congenital subglottic stenosis coexists, laryngotracheal reconstruction (LTR) with anterior cartilage grafting becomes necessary.

5. Congenital subglottic stenosis. Subglottic stenosis represents a significant cause of paediatric airway obstruction and warrants early recognition and intervention. The subglottis, anatomically, extends from approximately 10 mm below the anterior commissure and 5 mm below the posterior commissure to the lower border of the cricoid cartilage. Notably, it forms the narrowest portion of the infantile larynx, making it particularly vulnerable to both congenital and acquired stenosis.

Types: Subglottic Stenosis can be congenital or acquired.

• Congenital subglottic stenosis. It is the third most common congenital laryngeal anomaly. It arises due to incomplete canalisation of the cricoid cartilage and/or conus elasticus during the third month of foetal development. Two types are recognised: membranous and cartilaginous. The cartilaginous form, characterised by a thickened anterior cricoid lamina or a narrow elliptical cricoid ring, is frequently more resistant to conservative measures. Clinicians typically suspect congenital stenosis when they cannot pass an age-appropriate endotracheal tube, particularly if it measures below 3.5 mm in neonates. Flexible laryngoscopy can assist in confirming the diagnosis.
• Acquired subglottic stenosis predominantly results from trauma due to prolonged or oversized endotracheal intubation. The subglottic region’s vulnerability stems from the cricoid cartilage being a complete ring, which lacks the expansibility of other airway segments. Consequently, any inflammation or oedema severely narrows the lumen.
  Additional causes include direct laryngeal trauma, chronic infections (e.g., tuberculosis, syphilis, leprosy, typhoid fever), and systemic inflammatory diseases such as GERD, rheumatoid arthritis, lupus, or sarcoidosis. Clinically, acquired stenosis often manifests 2–4 weeks following the inciting event. Although some children remain asymptomatic initially, many develop progressive symptoms, especially following upper respiratory infections. Presenting features typically include biphasic or inspiratory stridor, dyspnoea, chest retractions, and a barking cough. Feeding difficulty and recurrent aspiration pneumonia may also occur.

Diagnosis and Assessment rely on rigid laryngoscopy under general anaesthesia, the gold standard. Measurement of the subglottic diameter confirms stenosis when the airway is less than 4 mm in full-term neonates (normal 4.5–5.5 mm) or 3 mm in preterm infants (normal 3.5 mm). Though X-rays may be helpful, a CT scan offers superior visualisation of the site and length of stenosis.

Management. The Myer-Cotton grading system, essential in evaluating stenosis severity, classifies subglottic narrowing into four grades. It helps to predict the outcome of surgical reconstruction. Surgical management aims to restore an adequate airway with a competent larynx and preserve voice.

• Grade I: 0–50% obstruction requires no surgical intervention and typically improves with the growth of the patient.
• Grade II: 51–70% obstruction requires an anterior graft with posterior cricoid split +/− posterior cartilage grafting.
• Grade III: 71–99% obstruction requires anterior and possibly posterior grafting.
• Grade IV: 100% obstruction requires anterior and posterior grafts with prolonged stenting.

Notably, congenital cartilaginous stenosis contraindicates endoscopic dilation or laser resection due to poor efficacy and risk of worsening the condition. When feasible, single-stage airway reconstruction using an endotracheal tube as a stent may eliminate the need for tracheostomy.

6. Subglottic haemangioma. It is a rare but clinically significant cause of upper airway obstruction in early infancy. Although congenital in origin, symptoms often do not manifest at birth. Instead, most patients remain asymptomatic until the haemangioma enters a proliferative phase between 3 and 6 months of age. During this period, the lesion grows rapidly, resulting in progressive respiratory symptoms such as inspiratory or biphasic stridor. Approximately 85% of affected infants present within the first six months of life. Importantly, nearly 50% of patients with subglottic haemangiomas also have associated cutaneous haemangiomas, which may serve as a diagnostic clue. Conversely, among children with cutaneous haemangiomas, about 1–2% may develop subglottic involvement. The natural course of these vascular tumours involves an initial proliferative phase that typically lasts 6–12 months, followed by spontaneous involution over 1 to 5 years.

Clinical Presentation. Infants may present with gradually worsening stridor while maintaining a normal cry. Notably, airway obstruction may intensify during episodes of agitation or crying due to increased venous engorgement of the lesion.

Diagnosis

• Direct laryngoscopy. Reveals a compressible, pear-shaped, reddish-blue swelling located just below the vocal cords, most commonly on the left side. Larger haemangiomas may exhibit a circumferential pattern and may extend into the trachea, surrounding soft tissues, or mediastinum.
• Biopsy. The lesion’s characteristic appearance usually eliminates the need for biopsy. However, in uncertain cases, biopsy can be performed safely, as subglottic haemangiomas are benign endothelial cell tumours rather than vascular malformations. Still, a potential risk of haemorrhage exists, though it remains minimal.
• MRI. If extraluminal extension is suspected.

Management.

• Propranolol – 1 mg/kg/day for 12 months, followed by a gradual taper over four weeks and gradually increased to 2–3 mg/kg/day, depending on the infant’s tolerance. Rapid improvement, especially in stridor, often occurs within 24 hours. Baseline ECG, echocardiogram, and blood glucose tests are essential.
• Steroids – Steroids may be added for propranolol resistant cases, with dexamethasone 1 mg/kg/day for a week, followed by prednisolone 3 mg/kg/day for up to a year. This combination enhances therapeutic response and may prevent progression.
• Surgical options include tracheostomy for severe obstruction, CO₂ laser excision for small lesions, and submucosal resection for non-circumferential lesions not involving the vocal cords.

7. Laryngo-oesophageal cleft. A laryngo-oesophageal cleft is a rare congenital anomaly caused by the failure of the fusion of the cricoid lamina. These clefts frequently coexist with other congenital anomalies, such as tracheo-oesophageal fistula (TOF), tracheomalacia, congenital heart defects, and syndromes like Opitz-Frias and Pallister-Hall.

The Benjamin-Inglis classification categorises clefts into four types, based on their anatomical extent. It relates well to symptoms and treatment.

• Type I – cleft is limited to the vocal cords.
• Type II – cleft extends below the vocal cords into the cricoid.
• Type III – cleft extends into the cervical trachea.
• Type IV – cleft extends into the thoracic trachea and may even reach the carina.

Clinical features. Symptom severity correlates with cleft length, ranging from mild cyanotic episodes on feeding in Type I to severe cardiopulmonary compromise in Type IV. The patient often presents with aspiration, recurrent pneumonia, coughing, choking, and cyanosis during feeding.

Diagnosis. Direct laryngobronchoscopy provides direct visualisation.

Management Treatment of laryngo-oesophageal clefts varies by type and aspiration severity.

• Type I clefts without aspiration need no intervention, while minimal aspiration improves with feed thickening. Significant aspiration requires endoscopic two-layer repair using a nasogastric tube.
• Short Type II clefts may also be repaired endoscopically. However, longer Type II and Type III clefts demand open repair via laryngofissure, tracheostomy, gastrostomy, and fundoplication. Surgeons reinforce the cleft with a three-layer closure including grafting.
• Type IV clefts require complex surgical approaches-often via median sternotomy with cardiopulmonary bypass or ECMO-due to airway instability. Postoperative tracheostomy may be necessary if tracheomalacia delays extubation.

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Download the full PDF Link:

Congenital lesions of the larynx Best Lecture Notes Dr Rahul Bagla ENT Textbook

Reference Textbooks.

• Scott-Brown, Textbook of Otorhinolaryngology-Head and Neck Surgery.
• Cummings, Otolaryngology-Head and Neck Surgery.
• Stell and Maran’s, Textbook of Head and Neck Surgery and Oncology.
• Ballenger’s, Otorhinolaryngology Head And Neck Surgery
• Susan Standring, Gray’s Anatomy.
• Frank H. Netter, Atlas of Human Anatomy.
• B.D. Chaurasiya, Human Anatomy.
• P L Dhingra, Textbook of Diseases of Ear, Nose and Throat.
• Hazarika P, Textbook of Ear Nose Throat And Head Neck Surgery Clinical Practical.
• Mohan Bansal, Textbook of Diseases of Ear, Nose and Throat Head and Neck Surgery.
• Hans Behrbohm, Textbook of Ear, Nose, and Throat Diseases With Head and Neck Surgery.
• Logan Turner, Textbook of Diseases of The Nose, Throat and Ear Head And Neck Surgery.
• Arnold, U. Ganzer, Textbook of  Otorhinolaryngology, Head and Neck Surgery.
• Ganong’s Review of Medical Physiology.
• Guyton & Hall Textbook of Medical Physiology.

Author:

Dr. Rahul Bagla
MBBS (MAMC, Delhi) MS ENT (UCMS, Delhi)
Fellow Rhinoplasty & Facial Plastic Surgery.
Renowned Teaching Faculty
Mail: msrahulbagla@gmail.com
India

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• Please read. Juvenile Angiofibroma. https://www.entlecture.com/juvenile-angiofibroma/
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Keywords: Congenital laryngeal anomalies, Laryngomalacia, congenital vocal cord paralysis, subglottic stenosis, pediatric airway obstruction, stridor