Most common cause of stridor sholy after bih –
**Core Concept**
Stridor is a high-pitched sound heard during inhalation, indicating upper airway obstruction. The most common cause of stridor in neonates is related to anatomical abnormalities or conditions that affect the airway.
**Why the Correct Answer is Right**
Laryngomalacia is the most common congenital anomaly of the larynx, accounting for 75% of cases of stridor in neonates. It is characterized by the softening of the cartilaginous structures of the larynx, leading to partial airway obstruction during inhalation. This condition is often due to the incomplete formation of the laryngeal cartilages and the subsequent collapse of the supraglottic airway.
**Why Each Wrong Option is Incorrect**
**Option A:** Vocal cord paralysis is a possible cause of stridor, but it is much less common in neonates compared to laryngomalacia.
**Option B:** Tracheomalacia refers to the weakening of the tracheal cartilages, which can cause stridor. However, it is less common than laryngomalacia and typically presents later in life.
**Option C:** Subglottic stenosis is a congenital or acquired narrowing of the airway below the vocal cords, which can cause stridor. However, it is less common in neonates and typically presents with symptoms of airway obstruction.
**Clinical Pearl / High-Yield Fact**
Laryngomalacia is often associated with other congenital anomalies, such as cardiac defects and gastrointestinal abnormalities. A high index of suspicion is necessary to diagnose this condition, as it may present with symptoms of respiratory distress or failure to thrive.
**Correct Answer: D. Laryngomalacia.**