Evaluation of the effect of supraglottoplasty on co-existing tracheomalacia in pediatric patients with congenital laryngotracheomalacia to establish the venturi effect in vivo. A prospective interventional study was conducted in a tertiary care hospital from 2020 to 2024. All consecutive pediatric patients undergoing supraglottoplasty for congenital laryngomalacia, with co-existing tracheomalacia on pre-operative bronchoscopic assessment were included and were assessed for change in severity of tracheomalacia by bronchoscopy and clinical parameters post-surgery as a comparison to the preoperative period. Twenty-eight patients including sixteen boys and twelve girls aged 1-30 months underwent supraglottoplasty. Statistically significant reduction in tracheal collapse was noted in all twenty-eight patients post-surgery on bronchoscopic evaluation (mean reduction by 41.45 ± 9.72 %). Clinically significant improvement was seen in terms of severity of stridor, frequency of hospitalization, apparent life-threatening events, z score for weight for age and parental perception of resolution of symptoms of their ward. Supraglottoplasty for correction of laryngomalacia results in significant improvement in co-existing tracheomalacia. Associated medical comorbidities were not found to affect the positive outcome. Supraglottoplasty being a simple surgery with insignificant complication rate and very high success rate may be considered as the first line of surgical intervention in severely symptomatic pediatric patients with laryngotracheomalacia. The term tracheomalacia indicates a condition characterized by a structural abnormality of the tracheal cartilage inducing excessive collapsibility of the trachea. It constitutes about half of the congenital pathologies of the trachea and is distinguished in diffuse and localized varieties depending on the extent of the disease. The distinction also concerns the primary forms due to an alteration of the development of the trachea and the secondary conditions produced by causes that act after the normal development of the organ. The primary forms can be diffuse or localized; the secondary ones are generally localized. Primary diffuse tracheomalacia is a rare congenital defect characterized by the immaturity of the cartilaginous rings (usually involving the distal third of the trachea), which leads to a weakness of the entire tracheal structure. It is more frequent in premature babies and can be associated with laryngomalacia or affect the trachea and other respiratory tracts. When the main bronchi are also affected, this condition is termed tracheobronchomalacia. Congenital tracheomalacia can combine with other congenital defects (e.g., cardiac defects), tracheoesophageal fistula, developmental delay, and gastroesophageal reflux (GER). Some conditions, such as vascular rings, can produce a localized primary defect in the development of the trachea. The secondary forms are acquired conditions that induce a weakening of the tracheal wall. These conditions can be ascribable to inflammatory processes that produce diffuse tracheomalacia, although these secondary forms are also the result of external compressions due to cardiovascular structures or other masses which produce localized areas of weakness of the tracheal wall.  In pathophysiological terms, the structural alterations of the trachea alter its mechanics. As by Poiseuille Law, even a small amount of narrowing in the lumen of the trachea can cause a significant decrease in airflow. Depending on the causative pathology (primary or secondary tracheomalacia and underlying diseases), patients’ symptoms may spontaneously resolve over the natural history of the disease or can cause persistent respiratory distress.

Congenital tracheomalacia can be the cause of respiratory failure in young children. Although the indication for surgical treatment has already been discussed vigorously, no clear guidelines about the modality are available. Through a sternotomy approach, a combination of posterior pexy and anterior tracheopexy using a tailored ringed polytetrafluoroethylene prosthesis is performed. Patient demographic characteristics, as well as operative details and postoperative outcomes, are included in the analysis. Between 2018 and 2022, 9 children underwent the operation under review. All patients showed severe clinical symptoms of tracheomalacia, which was confirmed on bronchoscopy. The median age was 9 months. There was no operative mortality. Eight patients could be weaned from the ventilator. One patient died because of interstitial lung disease with bronchomalacia and concomitant severe cardiac disease. The longest follow-up now is 4 years, and shows overall excellent clinical results, without any reintervention. Surgical treatment of tracheomalacia through a combination of posterior and anterior pexy is feasible, with acceptable short- and midterm results.

Congenital tracheomalacia is a pathology with no consensus of medical or surgical approach. The permanent nature and the major complications associated with metallic stents have limited their use over the years. The purpose of this study was to evaluate the feasibility of a helical stent design removal. Ten dogs diagnosed with tracheal collapse and treated with the helical stent were involved in the study. Animals were classified into three groups depending on stent indwelling time. Prior to the removal, endoscopic evaluation was performed to assess endothelization grade, mucous accumulation, and the presence of stenosis. During the removal, bleeding, fracture, or impossibility of removal were noted. After the removal, all macroscopic mucosal changes were recorded. Technical success was 100%, without any complications. Complete epithelization of the stent was visualized in 7/10 animals. The removal procedure duration ranged from 2-12 min. At post-removal endoscopy, bleeding or epithelial damage, was visualized in any case. Stent fracture during removal occurred in one animal. The removal of a metallic stent with spiral geometry is feasible, simple, and without complications, regardless of the degree of neo-epithelialization.

Congenital tracheomalacia, resulting from incomplete tracheal cartilage development, is a relatively common birth defect that severely impairs breathing in neonates. Mutations in the Hedgehog (HH) pathway and downstream Gli transcription factors are associated with tracheomalacia in patients and mouse models; however, the underlying molecular mechanisms are unclear. Using multiple HH/Gli mouse mutants including one that mimics Pallister-Hall Syndrome, we show that excessive Gli repressor activity prevents specification of tracheal chondrocytes. Lineage tracing experiments show that Sox9+ chondrocytes arise from HH-responsive splanchnic mesoderm in the fetal foregut that expresses the transcription factor Foxf1. Disrupted HH/Gli signaling results in 1) loss of Foxf1 which in turn is required to support Sox9+ chondrocyte progenitors and 2) a dramatic reduction in Rspo2, a secreted ligand that potentiates Wnt signaling known to be required for chondrogenesis. These results reveal a HH-Foxf1-Rspo2 signaling axis that governs tracheal cartilage development and informs the etiology of tracheomalacia.