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INTRODUCTION: Subglottic stenosis, manifested by granulation tissue hyperplasia, is challenging and requires multiple repeated treatments and stent maintenance at times. Corticosteroids prevent severe subglottic stenosis development owing to their antifibrotic and anti-inflammatory properties. Submucosal injection of glucocorticoids, a useful adjuvant therapeutic method, improves the mean interval between endoscopic procedures and reduces airway restenosis risks. CASE PRESENTATION: We report a rare case of a man with complex subglottic stenosis who underwent balloon dilatation combined with cryotherapy, stent placement, and adjuvant submucosal triamcinolone injection. The drug was injected efficiently and safely into the submucosal layer under percutaneous ultrasound guidance, and subglottic stenosis was well-controlled at a low cost. CONCLUSION: POCUS-guided medication injections may be a useful adjuvant medical therapy for subglottic stenosis.

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OBJECTIVE: Utilizing a novel histopathological scoring system and subglottic stenosis (SGS) rabbit model, we aimed to compare degrees of inflammation and severity of narrowing in the subglottis between two minimally invasive therapeutic modalities: endoscopic balloon dilation (EBD) alone versus EBD with placement of a bioabsorbable ultra-high ductility magnesium (UHD-Mg) alloy stent. METHODS: SGS was induced endoscopically via microsuspension laryngoscopy in 23 New Zealand white rabbits. The control group (n = 11) underwent EBD alone, the study arm (n = 12) underwent EBD with implantation of bioabsorbable UHD-Mg alloy stents. Rabbits were euthanized at 2-, 3-, and 6-weeks after SGS induction, coinciding with wound healing stages. Using Optical Coherence Tomography (OCT), cross-sectional areas of airways were compared to calculate the mean percentage of intraluminal area at sequential time points. A novel histopathological scoring system was used to analyze frozen sections of laryngotracheal complexes. The degree of inflammation was quantified by scoring changes in inflammatory cell infiltration, epithelial ulceration/metaplasia, subepithelial edema/fibrosis, and capillary number/dilation. Univariate analysis was utilized to analyze these markers. RESULTS: We found rabbits implanted with the bioabsorbable UHD-Mg alloy stent had statistically significantly higher scores in categories of hyperplastic change (stents vs controls: 1.48 vs 0.46 p < 0.001), squamous metaplasia (22 vs 5 p < 0.001), and neutrophils/fibrin in lumen (31 vs 8, p < 0.001). Rabbits who received EBD alone had higher scores of subepithelial edema and fibrosis (2.70 vs 3.49, p < 0.0256). The stented rabbits demonstrated significantly increased mean percent stenosis by intraluminal mean area compared to controls at 2 weeks (88.56 vs 58.98, p = 0.032), however at all other time points there was no significant difference between intraluminal subglottic stenosis by mean percent stenosis area. DISCUSSION: Rabbits with SGS treated with UHD-Mg alloy stents demonstrated histopathologic findings suggestive of lower levels of tracheal fibrosis. This could indicate a reduced tendency towards the development of stenosis when compared to EBD alone. There was not a difference in luminal size between stent and non-stented rabbits at the six-week end point. Histologically, however, overall the use of bioabsorbable UHD-Mg alloy stenting elicited a greater tissue response at the level of the superficial mucosa rather than fibrosis of the lamina propria seen in the stented rabbits. This suggests more favorable healing and less of a tendency towards fibrosis and stenosis even though there may not be a benefit from a luminal size standpoint during this early healing period. Compared to known complications of currently available non-bioabsorbable metal or silicone-based stents, this proof-of-concept investigation highlights the potential use of a novel biodegradable UHD-Mg stent as a therapeutic modality for pediatric SGS.

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PURPOSE: An accurate diagnosis and proper treatment plan are required to restore an adequate patent airway in fibrotic subglottic stenosis (SGS). Currently, the definitive treatment entails single-stage balloon dilatation with steroid injections. The primary aim was to evaluate successful airway restoration and general quality of life in cases with SGS in northern Sweden using robust patient reported outcomes. METHODS: All participants with need of surgical treatment due to SGS that had been referred to the department of otorhinolaryngology, University Hospital of Umeå from September 2020 to August 2023 was included. Exclusion criteria included malignant, extrathoracic or cartilaginous cause, age < 18 years, or incompetent to sign consent documents. We assessed the patient-reported outcome measures pre- as well as 3 months postoperatively. RESULTS: Of the 40 cases fulfilling the eligibility criteria's, 33 cases completed the Dyspnea index (DI) and the short form health survey (SF-36) pre- as well as 3 months post-operatively. Receiver operating characteristics showed significant improvement in DI as well as in SF 36 scores post-operatively. CONCLUSIONS: Evaluation of balloon dilatation in SGS in this cohort follow-up analysis shows clear improvement in patient quality of life using robust PROM 3 months postoperatively, ensuring the use of a safe and well-tolerated procedure.

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OBJECTIVES: The primary goal of this study was to systematically identify all relevant published articles on the use of primary endoscopic balloon dilation for the management of pediatric patients with subglottic stenosis, critically assess the technique's success, and determine which patients are the best candidates for the procedure. METHODOLOGY: This was a systematic review and meta-analysis that aimed to investigate the use and success rate of EBD for treating pediatric SGS. An electronic systematic literature search of three major databases, PubMed, EBSCO, and Web of Science&MEDLINE through Clarivate, was conducted to include the eligible articles. RESULTS: A total of 14 unique studies were included in the final analysis, with 473 cases of pediatric SGS. The pooled success rate of EBD in treatment of pediatric SGS was 76% (k = 14 studies, 95% confidence interval [CI] = 0.65-0.86, P < 0.001, Q test for heterogeneity = 0.03, P < .001, I2 = 91%). CONCLUSIONS: We reported a high success rate of EBD in treating pediatric SGS. The reported complications were uncommon, although they can be serious and life threatening. The intensity of SGS may be related to the likelihood of therapy failure.

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OBJECTIVES: A small number of Idiopathic subglottic stenosis (iSGS) patients are treated at institutions across the country. Divergence in operative techniques for endoscopic dilation (ED) of iSGS has been anecdotally recognized but not formally characterized. Additionally, the relationship between procedural variation and clinical outcome has not been studied. METHODS: Secondary analysis of the NoAAC iSGS1000 cohort investigated variation in procedural techniques and treatment outcomes in patients treated with ED across high-enrolling treatment centers (enrolled >10 patients in PR-02 trial). RESULTS: Thirteen NoAAC centers each enrolled >10 patients treated with ED for a total of 281 subjects. There was significant variation in procedural details and rate of recurrence among institutions. Hierarchal cluster analysis revealed significant heterogeneity among institutions and clusters in all procedural variables. However, analysis demonstrated a transient delay in disease recurrence in cluster 2 which disappeared with longer longitudinal follow-up. Patient-reported outcome and peak expiratory flow data supported the potential benefit of the technical variation in Cluster 2. Distinct to cluster 2, however, was routine use of adjuvant triple medical therapy (proton pump inhibitor (PPI), antibacterial agent, and steroid inhaler). CONCLUSIONS: Both outcome and procedural technique vary among centers employing ED to treat iSGS. A transient delay in recurrence was observed among centers that routinely prescribed adjuvant medical therapy (antibiotic, inhaled corticosteroid, and PPI) to iSGS patients after endoscopic dilation, which was further supported by patient-reported data and peak expiratory flow data. Prospective studies are needed to understand the effects of adjuvant medical therapy on recurrence after endoscopic dilation. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:3260-3266, 2024.

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BACKGROUND: Idiopathic subglottic stenosis (iSGS) is a recurrent, chronic disease defined by fibroinflammatory narrowing of the subglottic airway. A key challenge in treatment is monitoring disease progression, which may be debilitating and unpredictable in its timing. RESEARCH QUESTION: Can the Subglottic Stenosis 6 (SGS-6) questionnaire be validated as a novel quality-of-life (QOL) instrument to monitor breathing, disease progression, and disease severity proactively in patients with iSGS? STUDY DESIGN AND METHODS: Panel data from 51 patients with iSGS were collected from January 2012 through June 2022, representing 1,684 patient encounters including routine office visits and treatment encounters. Subjective QOL scores (including the novel SGS-6 and established RAND-36 and EuroQol Five Dimensions [EQ-5D] Visual Analog Scale) and objective pulmonary function test (PFT) results were collected at each visit. Subjective SGS-6 QOL scores were repeated within 1 week of initial reporting. Panel regression analyses were performed to assess the relationship between SGS-6 scores, PFT results, and a patient's need for intervention. Minimal clinically important differences (MCIDs) for SGS-6 and peak expiratory flow percentage (PEF%) were assessed using receiver operating characteristic (ROC) curve analysis and a patient's need for intervention as the external anchor. RESULTS: Each one-point increase in SGS-6 score (of a maximum of 27) was associated with a 3.26% decrease in PEF%, a 1.93-point decrease in RAND-36 Physical Health composite score, a 1.27-point decrease in RAND-36 Mental Health composite score, and a 0.88-point decrease in EQ-5D Visual Analog Scale score. The intracorrelation coefficient for the SGS-6 composite score is 0.838 (95% CI, 0.770-0.888). Compared with patient baselines, SGS-6 scores were 4.66 points greater at the time of intervention with an MCID of 2.25 from a patient's baseline. The area under the ROC curve for SGS-6 and a patient's intervention point was 0.81. INTERPRETATION: iSGS disease severity can be modeled using the SGS-6 questionnaire, offering physicians and patients a potentially new method of tracking disease progression and need for intervention remotely.

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OBJECTIVES: Congenital laryngotracheal stenosis is rare, potentially severe, and difficult to manage. Heliox is a medical gas effective in obstructive airway pathologies, given its physical properties. This study aims to model the interest of Heliox in reducing the respiratory work in congenital laryngotracheal stenosis, using numerical fluid flow simulations, before considering its clinical use. DESIGN: This is a retrospective study, performing Computational Fluid Dynamics numerical simulations of the resistances to airflow and three types of Heliox, on 3D reconstructions from CT scans of children presenting with laryngotracheal stenosis. PATIENTS: Infants and children who were managed in the Pediatric ENT department of a tertiary-care center and underwent CT scanning for laryngotracheal stenosis between 2008 and 2018 were included. RESULTS: Fourteen models of congenital laryngotracheal stenosis were performed in children aged from 16 days to 5 years, and one model of the normal trachea in a 5-year-old child. Tightest stenosis obtained the highest airway resistances, ranging from 40 to 10 kPa/L/s (up to 800 times higher than in the normal case). Heliox enabled a decrease in pressure drops and airway resistances in all stenosis cases, correlated to increasing Helium concentration. CONCLUSIONS: Heliox appears to reduce pressure drops and airway resistances in 3D models of laryngotracheal stenosis. It may represent a supportive treatment for laryngotracheal stenosis, while waiting for specialized care, thanks to the reduction of respiratory work.

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OBJECTIVE: Subglottic stenosis (SGS) is an unusual clinical condition of mucosal wounding, compromising the extra-thoracic part of the tracheal airway below the vocal folds. The diagnosis of SGS is established with a detailed clinical examination and a direct endoscopic examination, and the role of spirometry is also often acknowledged. This study aimed to investigate the impact of SGS on lung functions before and after the balloon dilation procedure. PATIENTS AND METHODS: The respiratory functions were performed in the Department of Clinical Physiology and the Department of Otolaryngology College of Medicine, King Saud University, Riyadh, Saudi Arabia. In this study, 50 patients with SGS were referred from the Department of Otolaryngology, and lung functions before and after the balloon dilation procedure among patients with SGS were performed using an electronic spirometer. RESULTS: The results revealed that the mean values for lung function test parameters VC (p=0.01), FVC (p=0.01), FEV1 (p=0.004), FEV1/FVC Ratio (p=0.01), PEFR (p=0.01), FEF-25% (p=0.01), FEF-50% (p=0.01), and FEF-75%, (p=0.01) were significantly improved in both male and female patients with SGS on one month after the balloon dilation procedure. CONCLUSIONS: It is concluded that the lung function test parameters were increased after the balloon dilation procedure among patients with SGS. The findings showed the impact of SGS on lung function test parameters. Spirometry is a valuable test in patients with SGS and is an appropriate marker to reveal post-airway outcomes. Physicians must suggest lung function tests in patients with SGS before and after the balloon dilation procedure.

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The aim of this article is to present experiences of the Department of Otorhinolaryngology and Head and Neck Surgery, Zagreb University Hospital Center with the treatment of patients with subglottic stenosis. Subglottic stenosis is a rare congenital or acquired disorder of airway patency that is part of a wider complex of disorders known as laryngotracheal stenosis with the ultimate effect in the form of respiratory insufficiency that can be life-threatening. As an acquired condition, it is most often the result of iatrogenic damage to the larynx and trachea during invasive airway management, whether it is intubation or tracheotomy. In the case of intubation as the etiologic factor, cases of prolonged intubation were most common. Retrospective analysis of patient medical histories over a ten-year period was performed and 29 patients met the inclusion criteria. All patients were monitored for at least two years after completion of treatment. Out of a total of 29 treated patients, 20 were permanently decannulated, of which 4 have paresis of one or both vocal cords. In conclusion, there is no clear treatment protocol for patients with subglottic stenosis. The optimal modality of treatment is combined endoscopic and open surgical treatment.

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Myxedema is a manifestation of severe hypothyroidism, and when affecting the larynx it constitutes a rare cause of upper airway obstruction. We present a case of laryngeal myxedema in a newborn causing subglottic stenosis. The atypical aspect of the stenosis along with a thyroid goiter and a positive screening for neonatal hypothyroidism allowed the diagnosis of laryngeal myxedema. Thyroid hormone replacement and non-invasive ventilation led to quick resolution while avoiding invasive approaches. Laryngeal myxedema is possibly underdiagnosed. Physician awareness is essential to avoid pitfalls in such children with reversible airway obstruction.

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Coronavirus disease (COVID-19) is associated with severe acute respiratory illness, often requiring intensive care unit admission. Some patients require prolonged intubation and mechanical ventilation. Post-intubation laryngotracheal stenosis occurs in approximately four to 13 % of adult patients after prolonged intubation in the absence of COVID-19 infection. The rate of COVID-19 related post-intubation laryngotracheal stenosis may be higher. Of 339 pregnant patients with COVID-19, we identified seven who required intubation and mechanical ventilation. Four of the seven developed persistent airway complications, and laryngotracheal stenosis, the most severe, was present in three. Each patient had variations in duration of intubation, endotracheal tube size, re-intubation, presence of superimposed infections, and pre-existing comorbidities. We speculate that underlying physiologic changes of pregnancy in addition to the increased inflammatory state caused by COVID-19 are associated with an increased risk of post-intubation laryngotracheal stenosis. Otolaryngology physicians should have a low threshold for considering this pathophysiology when consulting on obstetric patients who have previously been intubated with COVID-19. Otolaryngologists can educate obstetricians when caring for pregnant patients who have laryngotracheal stenosis, especially those who may require emergency airway management for obstetric indications.

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OBJECTIVE: Idiopathic subglottic stenosis describes subglottic stenosis where no inflammatory, traumatic, iatrogenic or other causative aetiology can be identified. The present study aimed to outline our institution's experience of patients diagnosed with idiopathic subglottic stenosis and describe a very rarely reported familial association. METHODS: A retrospective review was conducted of prospectively maintained medical records from 2011 to 2020. Patient clinical, radiological and intra-operative data were reviewed to assess for defined endpoints. RESULTS: Ten patients with idiopathic subglottic stenosis were identified in this series. One familial pairing was identified, with two sisters presenting with the condition. Successful treatment with carbon dioxide laser and dilatation was achieved in most cases. CONCLUSION: Idiopathic subglottic stenosis represents a rare, clinically challenging pathology. Management with endoscopic laser and balloon dilatation is an effective treatment. This paper highlights a very rare familial association, and describes our experience in treating idiopathic subglottic stenosis.

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OBJECTIVE: To explore the effects of interventional therapy with bronchoscopy in children with acquired subglottic stenosis (SGS). METHODS: The clinical data of ten pediatric inpatients with acquired SGS who were admitted to Children's Hospital of Chongqing Medical University, as well as their follow-up information obtained 1 week, 1 month, 3 months and 6 months after the procedure was done.were retrospectively analyzed to examine the effect of interventional bronchoscopic therapies, including balloon dilatation, holmium laser, and cryotherapy, in pediatric patients with acquired SGS. RESULTS: Among the 10 patients with acquired SGS, there were 5 boys and 5 girls aged between 1 month and 6 years and 5 months, with a median age of 11 months and 1 day. Among the 5 patients with acute acquired SGS, two were treated with balloon dilatation only, with one cured and one showing clinical improvement, while three received comprehensive interventional therapy combining balloon dilatation, holmium laser, and cryotherapy, with two cured and one showing improvement. Among the 5 patients with chronic acquired SGS, four cases were cured with comprehensive interventional therapy, while one case suffered from aggravated upper airway obstruction 4 + hours after balloon dilatation. The patient was subsequently put on invasive mechanical ventilation for 4 days, but was unable to be extubated. The parents signed do-not-resuscitate order and the patient died afterwards. Bronchoscopy performed 1 week, 1 month and 3 months after the procedure was done showed that the SGS was improved to varying degrees. CONCLUSION: Bronchoscopy intervention is an effective therapy for acquired SGS in children.

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BACKGROUND: Subglottic stenosis (SGS) and tracheal stenosis (TS) are characterized by a narrowing of the airways. The goal of this study was to describe the characteristics and prognosis of nontraumatic and nontumoral SGS or TS. RESEARCH QUESTION: What are the inflammatory etiologies of SGS and TS, and what are their characteristics and prognosis? STUDY DESIGN AND METHODS: This multicenter, observational retrospective study was performed in patients with SGS or TS that was neither traumatic nor tumoral. RESULTS: Eighty-one patients were included, 33 (41%) with granulomatosis with polyangiitis (GPA) and 21 (26%) with relapsing polychondritis (RP). GPA-related stenoses exhibited circumferential subglottic narrowing in 85% of cases, without calcifications. In contrast, RP-related stenoses displayed anterior involvement in 76%, in a longer distance from vocal cords (4 cm), with calcifications in 62%, and extension to bronchi in 86%. Other diagnoses included bullous dermatoses (n = 3), amyloidosis (n = 3), sarcoidosis (n = 2), and Crohn's disease (n = 2); the remaining stenoses (n = 15) were idiopathic. SGS/TS was the initial manifestation of the disease in 66% of cases, with a median interval from stenosis to disease diagnosis of 12 months (interquartile range, 0-48 months). Despite the use of glucocorticoids in 80%, combined with methotrexate in 49%, endoscopic procedures were required in 68% of patients. Relapses of stenoses occurred in 76% without any difference between causes (82% in GPA, 67% in RP, and 75% in idiopathic SGS/TS). Three patients died due to the stenosis, two of RP and one of GPA. INTERPRETATION: These data show that GPA and RP are the two main inflammatory diseases presenting with SGS/TS. GPA-related stenoses are mostly subglottic and circumferential, whereas RP-related stenoses are mostly tracheal, anterior, and calcified with a frequent extension to bronchi. Relapses of stenoses are common, and relapse rates do not differ between causes. Diagnosis and management of SGS/TS require a multidisciplinary approach.

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Histologically benign airway strictures are frequently misdiagnosed as asthma or COPD and may present with severe symptoms including respiratory failure. A clear understanding of pathophysiology and existing classification systems is needed to determine the appropriate treatment options and predict clinical course. Clinically significant airway strictures can involve the upper and central airways extending from the subglottis to the lobar airways. Optimal evaluation includes a proper history and physical examination, neck and chest computed tomography, pulmonary function testing, endoscopy and serology. Available treatments include medical therapy, endoscopic procedures and open surgery which are based on the stricture's extent, location, etiology, morphology, severity of airway narrowing and patient's functional status. The acuity of the process, patient's co-morbidities and operability at the time of evaluation determine the need for open surgical or endoscopic interventions. The optimal management of patients with benign airway strictures requires the availability, expertise and collaboration of otolaryngologists, thoracic surgeons and interventional pulmonologists. Multidisciplinary airway teams can facilitate accurate diagnosis, guide management and avoid unnecessary procedures that could potentially worsen the extent of the disease or clinical course. Implementation of a complex airway program including multidisciplinary clinics and conferences ensures that such collaboration leads to timely, patient-centered and evidence-based interventions. In this article we outline algorithms of care and illustrate therapeutic techniques based on published evidence.

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We describe a case of a 15-year-old girl diagnosed with relapsing polychondritis (RP) with involvement of the tracheobronchial tree, resulting in an increased difficulty in breathing, hoarseness of voice and stridor.Her case required the input of multiple specialities including ear, nose and throat, rheumatology, respiratory team and intensive care. Airway assessment and imaging showed glottic and subglottic stenosis and left bronchomalacia. Despite the use of steroids, cyclophosphamide and rituximab, her symptoms progressed and she was started on overnight non-invasive ventilation.She had further relapses of her airway RP-she was started on adalimumab and methotrexate and underwent monthly balloon dilatations which helped with her symptoms and facilitated a safe discharge home. However, she had further relapses and intensive care admissions and following further discussions, a tracheostomy was inserted. She is now stable on her tracheostomy and is off any respiratory support.

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OBJECTIVES/HYPOTHESIS: Adjuvant medications including proton pump inhibitors (PPI), antibiotics (trimethoprim/sulfamethoxazole [TMP-SMX]), and inhaled corticosteroids (ICS) may be prescribed for patients with idiopathic subglottic stenosis (iSGS). We describe medication use with endoscopic dilation (ED) or endoscopic resection with medical treatment (ERMT) and evaluate impact on outcomes. STUDY DESIGN: International, prospective, 3-year multicenter cohort study of 810 patients with untreated, newly diagnosed, or previously treated iSGS. METHODS: Post hoc secondary analysis of prospectively collected North American Airway Collaborative data on outcomes linked with adjuvant medication utilization. Primary outcome was time to recurrent operation, evaluated using Kaplan-Meier curves and Cox regression analysis. Secondary outcomes of change in peak expiratory flow (PEF) and clinical chronic obstructive pulmonary disease questionnaire (CCQ) score over 12 months were compared. RESULTS: Sixty-one of 129 patients undergoing ED received PPI (47%), and 10/143 patients undergoing ED received ICS (7%). TMP-SMX was used by 87/115 patients (76%) undergoing EMRT. PPI use in the ED group did not affect time to recurrence (hazard ratio [HR] = 1.00, 95% confidence interval [CI]: 0.53-1.88; P = .99) or 12-month change in PEF (L/min) (median [interquartile range], 12.0 [10.7-12.2] vs. 8.7 [-5.1 to 24.9]; P = .59), but was associated with 12-month change in CCQ (-0.05 [-0.97 to 0.75] vs. -0.50 [-1.60 to 0.20]; P = .04). ICS did not affect outcome measures. TMP-SMX use in ERMT did not affect time to recurrence (HR = 0.842, 95% CI: 0.2345-3.023; P = .79), PEF at 12 months (75 [68-89] vs. 81 [68-89]; P = .92), or 12-month change in CCQ (0.20 [-1.05 to 0.47] vs. -0.30 [-1.00 to 0.10]; P = .45). CONCLUSION: There is no standard practice for prescribing adjuvant medications. These data do not support that adjuvant medications prolong time to recurrence or increase PEF. Patients with iSGS and gastroesophageal reflux disease may experience some symptom benefit with PPI. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:E2880-E2886, 2021.

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Laryngeal stenosis is certainly one of the most severe complications of airway intubation in children, eventually leading to tracheostomy and sometimes to additional surgical procedures. Primary prophylaxis through modification of its risk factors and secondary prophylaxis through the management of post-extubation laryngeal acute lesions seem to be key to avoidance of this fearful complication. The present article addresses known risk factors for the development of laryngeal acute lesions with emphasis on sedation level and intubation time. It also discusses available classification systems proposed in medical literature, especially the Classification of Acute Laryngeal Injuries (CALI) conceived by our research group, and its positive predictive value for the development of chronic lesions. Finally, debate focuses on treatment of each individual lesion. Despite excellent results observed with endoscopic methods for treating these lesions, there is still doubts pending over their management, and there is need for further studies to define adequate treatment for each patient and for each type of lesion.

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