[The use of the dura mater at the final stage of reconstructive plastic surgical treatment of cicatricial stenosis of the larynx and trachea]. / Ispol'zovanie tverdoi mozgovoi obolochki pri zaklyuchitel'nom etape rekonstruktivno-plasticheskogo operativnogo lecheniya rubtsovogo stenoza gortani i trakhei.

The article presents an analysis of the plastic reconstructive surgery effectiveness for patients with an extended tracheal defect using an allograft based on the dura mater (DM) at the final stage of surgical treatment of laryngeal and tracheal cicatricial stenosis. The study included 20 patients with cicatricial stenosis of the larynx and trachea, who were previously performed plastic reconstructive treatment with scar tissue excision in the lumen of the respiratory tract and restoration of the supporting frame of the larynx and trachea using allografts based on costal allocartilage. The age of the patients ranged from 21 to 54 years, the duration of the disease was from 1 to 5 years. After a standard clinical and laboratory examination, with a mandatory video endoscopic examination of the larynx and trachea, multislice computed tomography of the larynx and trachea, patients underwent plastic closure of the tracheal defect using DM. Dynamic outpatient monitoring was carried out once a week for 1 month, once a month for 3 months, control examination was done 6 months after surgical treatment. The results of the study demonstrated a full-fledged social and labor rehabilitation of all 20 patients after the final stage of surgical treatment using DM, the absence of rejection reaction and migration of allo-implantation material, the preserved lumen of the larynx and trachea with a rigid supporting skeleton and the absence of anterior tracheal wall floatation. The use of DM as an additional strengthening of the anterior tracheal wall for patients with deficiency of muscular aponeurotic tissues and more than 2 cm size tracheal defect is highly effective at the final stage of surgical treatment for plastic closure of the tracheal defect.

Subcutaneous fixation model for complex stenting of recurrent laryngotracheal stenosis.

BACKGROUND: A straight silicone stent can be used to treat proximal benign tracheal stenosis in non-surgical candidates. However, stent migration is a common complication when placed at a particular location and can lead to major complications. This case series of laryngotracheal stenosis reports a fixation method for straight silicone stents in the subglottic trachea (Stage 3 of the McCaffrey classification). METHODS: The medical charts of these patients scheduled for straight silicone stent placement with suture fixation between 2014 and 2020 at the CHU UCL Namur Hospital (Belgium) were retrospectively reviewed. The procedure was performed using a rigid bronchoscope. Details of the procedure were obtained from medical records. RESULTS: This case series included six patients (males: 4, females: 2). The median patient age was 59 years. Two suture fixations were placed following previous silicone stent migration episodes, whereas the others were placed proactively to avoid this risk. All fixations were performed by the device Freka® Pexact II ENFIt®, originally developed for gastropexy in endoscopic gastrostomy. The sutures were subcutaneously buried. CONCLUSIONS: During the 6-month follow-up period, complications such as fixation issues and stent migration were reported despite the off-label use of the treatment. The straight silicone stent fixation technique used in this case series was simple and effective for securing the stent in upper benign tracheal stenosis.

Characterizing Dysphonia After Pediatric Open Airway Reconstruction: Systematic Review and Meta-Analysis.

BACKGROUND: Pediatric laryngotracheal stenosis often requires open airway reconstruction. While these surgeries establish an airway for adequate ventilation, many patients develop subsequent dysphonia. Numerous studies have reported outcomes related to voice. OBJECTIVE: This study aims to evaluate dysphonia in pediatric patients following open airway reconstruction, focusing on acoustic parameters, perceptual voice quality, and voice-related quality of life. METHODS: A comprehensive search using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines across 6 databases identified articles involving pediatric patients who underwent open airway reconstruction and reported postoperative vocal acoustic parameters, perceptual voice quality, voice-related quality of life, or vocal mechanics. Articles were assessed for bias risk, and common outcomes were synthesized qualitatively and quantitatively using meta-analyses. RESULTS: Among 4089 articles, 21 were included, involving 497 pediatric patients. Laryngotracheoplasty was the most common procedure followed by cricotracheal resection. The Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V) scale was frequently used to assess voice quality, with a mean score of 55.6 [95% confidence intervals (CIs): 47.9-63.3]. Voice-related quality of life was measured using the pediatric Voice Handicap Index (pVHI) and Pediatric Voice-Related Quality of Life Survey, with mean scores of 35.6 (95% CI: 21.4-49.7) and 83.7 (95% CI: 74.1-93.2), respectively. The fundamental frequency was 210.5 (95% CI: 174.6-246.3). Other common findings included supraglottic phonation, anterior commissure blunting, posterior glottic diastasis, and abnormal vocal cord mobility. CONCLUSION: Pediatric patients experiencing dysphonia after open airway reconstruction exhibited moderately decreased voice quality and reduced voice-related quality of life. However, there was inconsistency in study protocols and outcome measures used. Preserving voice quality during airway reconstruction is crucial to avoid negative impacts on quality of life.

The impact of previous endoscopic treatments on functional outcome after cricotracheal resection.

OBJECTIVES: Treatment options for benign subglottic stenosis include endoscopic techniques or open surgery. Although endoscopic treatment is less invasive, a considerable proportion of patients develop recurrent stenosis. Endoscopic pretreatments do not exclude patients from a later surgical repair; however, the impact of previous endoscopic treatment attempts on functional outcome after open surgery is unknown. METHODS: All patients, who received a cricotracheal resection (CTR) between January 2017 and June 2023 at the Department of Thoracic Surgery, Medical University of Vienna, were included in this retrospective study. Patient characteristics, surgical variables and postoperative outcome including a detailed functional assessment were analysed. RESULTS: A total of 65 patients received a CTR during the study period, of which 40 were treatment naïve and 25 had a median of 2 (range 1-9) endoscopic pretreatments. Less-invasive voice-sparing CTR or standard CTR were more often possible in treatment-naïve patients. In contrary, pretreated patients regularly required extended procedures (P = 0.049). Three or more endoscopic treatments resulted in a significantly lower mean fundamental frequency (F0) after open repair (P = 0.048). In addition, a trend towards smaller mean sound pressure levels, a higher voice handicap index, higher impairments in RBH scores (roughness, breathing and hoarseness) and a higher dysphagia severity index was found in pretreated patients. The respiratory outcome after surgery was comparable between both groups. CONCLUSIONS: Multiple endoscopic pretreatments lead to worse voice quality after CTR. The impact of prior endoscopic treatment before surgical repair should be considered when discussing treatment options with patients suffering from subglottic stenosis.

Degrees of Inflammation in the Treatment of Subglottic Stenosis in a Rabbit Model: Histopathological Assessment of a Novel Bioabsorbable Ultra-high Ductility Magnesium Alloy Stent.

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.

Stridor and severe subglottic stenosis: emergency tracheostomy for a neonate with a pinhole trachea.

Congenital subglottic stenosis is a rare but potentially catastrophic condition. In this report, we describe the management of a term neonate who was noted to have biphasic stridor during preassessment for correction of an imperforate anus at 26 hours of life. The neonate was found to have a pinhole trachea secondary to congenital subglottic stenosis. It was impossible to pass an endotracheal tube, so the neonate underwent an emergency surgical tracheostomy with a good outcome. A high index of suspicion led to appropriate steps being taken to safely anaesthetise the neonate.

POSTN Regulates Fibroblast Proliferation and Migration in Laryngotracheal Stenosis Through the TGF-ß/RHOA Pathway.

OBJECTIVES: To investigate the role of periostin (POSTN) and the transforming growth factor ß (TGF-ß) pathway in the formation of laryngotracheal stenosis (LTS) scar fibrosis and to explore the specific signaling mechanism of POSTN-regulated TGF-ß pathway in tracheal fibroblasts. METHODS: Bioinformatics analysis was performed on scar data sets from the GEO database to preliminarily analyze the involvement of POSTN and TGF-ß pathways in fibrosis diseases. Expression of POSTN and TGF-ß pathway-related molecules was analyzed in LTS scar tissue at the mRNA and protein levels. The effect of POSTN on the biological behavior of tracheal fibroblasts was studied using plasmid DNA overexpression and siRNA silencing techniques to regulate POSTN expression and observe the activation of TGF-ß1 and the regulation of cell proliferation and migration via the TGF-ß/RHOA pathway. RESULTS: The bioinformatics analysis revealed that POSTN and the TGF-ß pathway are significantly involved in fibrosis diseases. High expression of POSTN and TGF-ß/RHOA pathway-related molecules (TGFß1, RHOA, CTGF, and COL1) was observed in LTS tissue at both mRNA and protein levels. In tracheal fibroblasts, overexpression or silencing of POSTN led to the activation of TGF-ß1 and regulation of cell proliferation and migration through the TGF-ß/RHOA pathway. CONCLUSION: POSTN is a key molecule in scar formation in LTS, and it regulates the TGF-ß/RHOA pathway to mediate the formation of cicatricial LTS by acting on TGF-ß1. This study provides insights into the molecular mechanisms underlying LTS and suggests potential therapeutic targets for the treatment of this condition. LEVEL OF EVIDENCE: NA Laryngoscope, 134:4078-4087, 2024.

Mapping quality of life after balloon dilatation in subglottic stenosis using Dyspnea index and Short Form Health Survey-36.

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.

Reconstructive Surgery of the Laryngotracheal Junction. / Rekonstruktive Chirurgie des laryngo-trachealen Übergangs.

The laryngotracheal junction is an anatomical region with special pathophysiological features. This review presents clinical pictures and malformations that manifest pre-dilectively at this localisation in children and adolescents as well as in adults. The diagnostic procedure is discussed. The possibilities of surgical reconstruction are presented depending on the pathology and age of the patient.

Endoscopic posterior cricoid split with costal cartilage graft placement in patients under one year of age.

Endoscopic posterior cricoid split and costal rib graft placement (EPCSCG) is an important tool in enlarging the glottic and subglottic airway, both of which can be disproportionally affected in the small airways of neonates and early infants. We present a series of 8 patients under the age of one who successfully underwent EPCSCG, with 7/8 patients avoiding tracheostomy entirely. Of these patients, the indication for EPCSCG was isolated bilateral vocal fold immobility (6/8), bilateral vocal fold immobility with subglottic stenosis (1/8), and isolated subglottic stenosis (1/8). EPCSCG can be safely applied to select patients less than one year of age.

Congenital glottic stenosis as a clinical manifestation of FREM1-associated disorders in a neonate with respiratory distress and aphonia.

A female infant born at 38 weeks and 2 days via induced vaginal delivery was admitted to the neonatal intensive care unit for respiratory distress soon after birth. Noted to have aphonia on examination, the patient underwent direct laryngoscopy and was diagnosed with an anterior glottic web and subglottic stenosis. The patient underwent a genetic workup including whole exome sequencing which resulted in a diagnosis of a FREM1-associated disorder. Congenital glottic webs and subglottic stenoses have not been previously described as clinical manifestations of FREM1-associated disorders.

Endoscopic balloon dilatation for pediatric subglottic stenosis: a meta-analysis of successful outcomes.

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.

Impact of BMI on Dyspnea and Need for Surgical Intervention in Bilateral Vocal Fold Immobility.

OBJECTIVE: Bilateral vocal fold paralysis (BVFP) and posterior glottic stenosis (PGS) are causes of bilateral vocal fold immobility (BVFI) and may cause shortness of breath, stridor, and need for surgical intervention. Although increased body mass index (BMI) is associated with restrictive breathing patterns in patients with normal upper airways, it is unclear how BMI impacts dyspnea and need for surgical intervention in BVFI patients. STUDY DESIGN: Retrospective cohort study. SETTING: Three tertiary academic centers in the United States. METHODS: Demographics, BMI, Dyspnea Index (DI), etiology, presence of tracheostomy and surgical intervention (dilation, tracheostomy, cordotomy, arytenoidectomy, open reconstruction) were collected. Primary outcomes included dyspnea measured by DI and need for surgery to improve airway. Linear regressions were performed to assess continuous outcomes. Mann-Whitney U-test was utilized to assess categorical outcomes. RESULTS: Among 121 patients, 52 presented with BVFP and 69 with PGS. Previous neck surgery was the most common cause of BVFI (40.2%). 44.3% of patients received a tracheostomy. Through multivariate linear regression, increased BMI was significantly associated with increased DI in the entire cohort (ß = .43, P = .016). Increased BMI was also associated with need for any surgical intervention (odds ratio [OR] = 1.07, 95% confidence interval [CI] = [1.01-1.13]) in the overall cohort. When stratifying our data, BMI was only significantly associated with DI in BVFP (ß = .496) and need for surgical intervention in PGS (OR = 1.11, 95% CI = [1.01-1.21]), although a positive trend was seen in all analyses. CONCLUSION: Increased BMI may correlate with worsening dyspnea symptoms and need for surgical intervention in patients with BVFI. Weight-loss-related counseling may benefit symptom management.

Assessing the interrater and intrarater reliability of subglottic stenosis grading systems.

BACKGROUND: Subglottic stenosis (SGS) is a condition leading to narrowing of the upper airway which can lead to dyspnea and life-threatening airway obstruction. Although other proposed grading systems exist, the Cotton Myer (CM) and percent stenosis systems are the most widespread in clinical practice. Despite this, the CM system has not yet been validated for visual assessment of SGS. OBJECTIVE: To determine the interrater and intrarater reliability of the CM grading system among a cohort of physicians who manage patients with SGS. METHODS: An online survey created with videos of tracheoscopies from 20 adult patients with subglotticstenosis (SGS) was sent individually to 9 expert physicians from various medical specialties, all of whom managed patients with SGS. Physicians were asked to view the 20 tracheoscopy videos and assess both the percent stenosis and Cotton Myer (CM) grade of each patient. After a period of 4 weeks, the physicians were sent the same survey of the 20 tracheoscopy videos. The interrater and intrarater reliability was calculated using the intraclass correlation coefficient (ICC), a measurement used to evaluate the reliability (the extent to which a measurement can be replicated) of two or more raters measuring the same subject. RESULTS: Overall, CM and percent stenosis systems were found to have an ICC of 0.94 and 0.90 within the domain of interrater reliability, respectively, and ICC of 0.71 and 0.81 within the domain of intrarater reliability, respectively. CONCLUSION: Our findings suggest that the CM and percent stenosis grading systems remain a valid clinical tool to measure and communicate the severity of airway obstruction in SGS.

In-depth analysis of pre- and postoperative functional outcome parameters in patients receiving laryngotracheal surgery.

OBJECTIVES: Surgical treatment for airway stenosis necessitates personalized techniques based on the stenosis location and length, leading to favourable surgical outcomes. However, there is limited literature on functional outcomes following laryngotracheal surgery with an adequate number of patients. METHODS: We conducted a retrospective analysis of patients who underwent laryngotracheal surgery at the Department of Thoracic Surgery, Medical University of Vienna, from January 2017 to June 2021. The study included standardized functional assessments before and after surgery, encompassing spirometry, voice measurements, swallowing evaluation and subjective patient perception. RESULTS: The study comprised 45 patients with an average age of 51.9 ± 15.9 years, of whom 89% were female, with idiopathic being the most common aetiology (67%). Procedures included standard cricotracheal resection in 11%, cricotracheal resection with dorsal mucosal flap in 49%, cricotracheal resection with dorsal mucosal flap and lateral cricoplasty in 24% and single-stage laryngotracheal reconstruction in 16%. There were no in-hospital mortalities or restenosis cases during the mean follow-up period of 20.8 ± 13.2 months. Swallowing function remained intact in all patients. Voice evaluations showed a decrease in fundamental vocal pitch [203 (81-290) Hz vs 150 (73-364) Hz, P < 0.001] and dynamic voice range (23.5 ± 5.8 semitones vs 17.8 ± 6.7 semitones, P < 0.001). However, no differences in voice volume were observed (60.0 ± 4.1 dB vs 60.2 ± 4.8 dB, P = 0.788). The overall predicted voice profile changed from R0B0H0 to R1B0H1. CONCLUSIONS: Laryngotracheal surgery proves effective in fully restoring breathing capacity while preserving vocal function. Even in cases of high-grade and complex airway stenosis necessitating laryngotracheal reconstruction, favourable functional outcomes can be achieved.

Factors affecting graft healing in laryngotracheal reconstruction: a retrospective single-center experience.

PURPOSE: To examine the factors that affect graft healing after laryngotracheal reconstruction (LTR). METHODS: We conducted a retrospective chart review at King Abdulaziz University Hospital, Riyadh, Saudi Arabia, between January-2008 and October-2023. We included all patients who underwent LTR and required anterior and/or posterior graft placement, while those who underwent procedures without graft placement and those with incomplete information were excluded. RESULTS: Forty-nine patients were analyzed. Most patients were pediatric (65.3%), male (65.3%), had no coexisting comorbidities (55.1%), and harbored grade 3-4 stenosis (59.2%). Thirty patients (61.2%) underwent open surgery. Various graft complications occurred including infection (n = 1, 2%), dehiscence (n = 3, 6.1%), scar (n = 6, 12.2%), and granulation (n = 29, 59.2%). Only 15 patients (30.65%) achieved the composite status of "healthy" graft. Among 43 patients who had postoperative cultures, positive results for Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus were observed in 10 and four patients, respectively. Open surgery and double-stage procedure were significantly associated with higher rates of granulation tissue formation. Pediatric-age group had significantly higher rate of complete epithelization compared to adult-age group. A significantly greater proportion of patients who had unhealthy grafts had open surgery. The rate of double-stage LTR was significantly higher in unhealthy grafts compared to healthy grafts. Prolonged stent duration was linked to various graft-related complications. Multivariate logistic regression analyses showed no statistically significant correlations between various factors and postoperative graft-related complications. CONCLUSION: Open surgery, double-stage procedure, pediatric age group, and stent duration were not significant risk factors associated with postoperative graft-related complications during LTR in multivariate analysis.

[Application of acellular dermal matrix in prevention of laryngeal stenosis in glottic carcinoma].

Objective:To investigate the effect of acellular dermal matrix in preventing laryngeal stenosis in glottic carcinoma patients. Methods:Fifty-five patients with glottic carcinoma（T2, T3） from February 2018 to December 2022 were divided into experimental group（28 cases） and control group（27 cases） according to their wishes. Acellular dermal matrix was placed in the operation cavity in the experimental group after laryngofission, while control group 12 cases were sutured by pulling the upper and lower edges, 15 cases were repaired with sternohyoid muscle fascia flap. Results:In the experimental group, 1 case had laryngeal stenosis caused by laryngeal mucosa swelling after operation, and extubated successfully after symptomatic treatment. In the control group, 7 cases had laryngeal stenosis after operation, of which 3 cases were caused by granulation tissue hyperplasia in laryngeal cavity, and extubated after symptomatic treatment. 2 cases extubated after operation suffered from progressive dyspnea during radiotherapy, and underwent tracheotomy again, extubation successful after treatment. 2 cases caused by laryngeal mucosa swelling, after symptomatic treatment, one case was successfully extubated, and one case had long-term intubation. The laryngeal stenosis rate of the experimental group was 3.6%（1/28） , which was lower than control group 25.9%（7/27）, and the therapeutic effect of the experimental group was significantly better than control group （χ²=5.526, P=0.019）. Conclusion:Implanting acellular dermal matrix in the operation cavity of glottic carcinoma can reduce the occurrence of laryngeal stenosis and have satisfactory preventive effect on laryngeal stenosis.

Lipoaspirate Injection in Relapsing Idiopathic Subglottic Stenosis: Preliminary Results.

OBJECTIVES: The management of idiopathic subglottic stenosis (iSGS) poses a clinical challenge due to high recurrence rates following both endoscopic and open approaches, often leading to tracheostomy. The activation of abnormal T-cells and cytokine pathways has been linked to iSGS pathogenesis. Autologous adipose tissue centrifugation yields lipoaspirate, offering optimal anti-inflammatory effects and biocompatibility widely utilized in various medical settings. This report presents the first 3 cases employing endoscopic dilation (ED) in combination with local lipoaspirate injection to address recurrent iSGS. METHODS: A prospective observational study was conducted, involving multidisciplinary evaluation by the Tracheal Team at the University of Modena. Patients meeting specific criteria were directed to undergo ED + lipoaspirate injection. RESULTS: Three patients fulfilled the inclusion criteria. The mean number of prior endoscopic procedures performed was 8. Endoscopic examination revealed 90% stenosis in patient A, 60% stenosis in patient B, and 60% stenosis in patient C. All patients presented inflammatory tissue or incipient granulations at the stenotic site, with an average time of 6 months between previous procedures. After 15 months, none of the patients required further procedures, and endoscopic examination revealed a significant reduction or disappearance of inflammatory tissue with a stable airway lumen. CONCLUSIONS: The observed results are encouraging in terms of reducing local inflammation and halting stenosis progression, especially in cases of short-term relapsing iSGS.

Similarity Network Analysis of the Adaptive Immune Response in the Proximal Airway.

OBJECTIVES: Recent immunologic study of the adaptive immune repertoire in the subglottic airway demonstrated high-frequency T cell clones that do not overlap between individuals. However, the anatomic distribution and antigenic target of the T cell repertoire in the proximal airway mucosa remain unresolved. METHODS: Single-cell RNA sequencing of matched scar and unaffected mucosa from idiopathic subglottic stenosis patients (iSGS, n = 32) was performed and compared with airway mucosa from healthy controls (n = 10). T cell receptor (TCR) sequences were interrogated via similarity network analysis to explore antigenic targets using the published algorithm: Grouping of Lymphocyte Interactions by Paratope Hotspots (GLIPH2). RESULTS: The mucosal T cell repertoire in healthy control airways consisted of highly expressed T cell clones conserved across anatomic subsites (trachea, bronchi, bronchioles, and lung). In iSGS, high-frequency clones were equally represented in both scar and adjacent non-scar tissue. Significant differences in repertoire structure between iSGS scar and unaffected mucosa was observed, driven by unique low-frequency clones. GLIPH2 results suggest low-frequency clones share targets between multiple iSGS patients. CONCLUSION: Healthy airway mucosa has a highly conserved T cell repertoire across multiple anatomic subsites. Similarly, iSGS patients have highly expressed T cell clones present in both scar and unaffected mucosa. iSGS airway scar possesses an abundance of less highly expanded clones with predicted antigen targets shared between patients. Interrogation of these shared motifs suggests abundant adaptive immunity to viral targets in iSGS airway scar. These results provide insight into disease pathogenesis and illuminate new treatment strategies in iSGS. LEVEL OF EVIDENCE: NA Laryngoscope, 134:3245-3252, 2024.