An Ovine Model Yields Histology and Gene Expression Changes Consistent with Laryngotracheal Stenosis

OBJECTIVES

Animal models for laryngotracheal stenosis (LTS) are critical to understand underlying mechanisms and study new therapies. Current animal models for LTS are limited by small airway sizes compared to human. The objective of this study was to develop and validate a novel, large animal ovine model for LTS.

METHODS

Sheep underwent either bleomycin-coated polypropylene brush injury to the subglottis (n = 6) or airway stent placement (n = 2) via suspension microlaryngoscopy. Laryngotracheal complexes were harvested 4 weeks following injury or stent placement. For the airway injury group, biopsies (n = 3 at each site) were collected of tracheal scar and distal normal regions, and analyzed for fibrotic gene expression. Lamina propria (LP) thickness was compared between injured and normal areas of trachea.

RESULTS

No mortality occurred in sheep undergoing airway injury or stent placement. There was no migration of tracheal stents. After protocol optimization, LP thickness was significantly increased in injured trachea (Sheep #3: 529.0 vs. 850.8 um; Sheep #4: 933.0 vs. 1693.2 um; Sheep #5: 743.7 vs. 1378.4 um; Sheep #6: 305.7 vs. 2257.6 um). A significant 62-fold, 20-fold, 16-fold, 16-fold, and 9-fold change of COL1, COL3, COL5, FN1, and TGFB1 was observed in injured scar specimen relative to unaffected airway, respectively.

CONCLUSION

An ovine LTS model produces histologic and transcriptional changes consistent with fibrosis seen in human LTS. Airway stent placement in this model is safe and feasible. This large airway model is a reliable and reproducible method to assess the efficacy of novel LTS therapies prior to clinical translation.

LEVEL OF EVIDENCE

N/A Laryngoscope, 2024.

A Comprehensive Flow Cytometry Panel for Analysis of Idiopathic Subglottic Stenosis

OBJECTIVE

To present a comprehensive flow cytometry panel for idiopathic subglottic stenosis (iSGS).

STUDY DESIGN

Controlled ex vivo cohort study.

SETTING

Tertiary care academic hospital in a metropolitan area.

METHODS

Flow cytometry and single-cell RNA sequencing were performed on 9 paired normal and scar tissue samples from iSGS patients. Flow cytometry was used to assess the presence of myeloid (CD11b, CD14, CD15, Siglec8), lymphoid (CD3, CD4, CD8, gamma delta [γδ], FOXP3), endothelial (CD31), fibroblast (CD90, SMA), and epithelial (CD326, CK5) markers.

RESULTS

On flow cytometry, iSGS scar is characterized by an increased presence of myeloid, lymphoid, endothelial, and fibroblast cell types, but a decreased presence of epithelial cells. In the myeloid lineage, iSGS scar samples demonstrated increased CD11b+ monocytes (P < .001), Siglec8+ eosinophils (P = .03), and CD14+ monocytes (P = .02). In the lymphoid lineage, iSGS scar demonstrated increased CD3+ T-cells (P < .001), CD4+ helper T-cells (P < .001), γδ+ T-cells (P < .001), and FOXP3+ regulatory T-cells (P = .002). iSGS scar exhibited specific increases in CD90+ (P = .04) and SMA+ (P < .001) fibroblasts but decreased CD326+ (E-cadherin) epithelial cells (P = .01) relative to normal samples.

CONCLUSION

We present a comprehensive flow cytometry panel for iSGS. This flow panel may serve as a common platform among airway scientists to elucidate the cellular mechanisms underpinning iSGS and other upper airway pathologies. Scar iSGS samples demonstrate a distinct cellular profile relative to normal iSGS specimens, exhibiting increased fibroblast, endothelial, and inflammatory cell types but decreased epithelium.

Characterizing the T Cell Repertoire in the Proximal Airway in Health and Disease

OBJECTIVES

Recent translational scientific efforts in subglottic stenosis (SGS) support a disease model where epithelial alterations facilitate microbiome displacement, dysregulated immune activation, and localized fibrosis. Given the observed immune cell infiltrate in SGS, we sought to test the hypothesis that SGS cases possessed a low diversity (highly clonal) adaptive immune response when compared with healthy controls.

METHODS

Single cell RNA sequencing (scRNA-seq) of subglottic mucosal scar in iSGS (n = 24), iLTS (n = 8), and healthy controls (n = 7) was performed. T cell receptor (TCR) sequences were extracted, analyzed, and used to construct repertoire structure, compare diversity, interrogate overlap, and define antigenic targets using the Immunarch bioinformatics pipeline.

RESULTS

The proximal airway mucosa in health and disease are equally diverse via Hill framework quantitation (iSGS vs. iLTS vs. Control, p > 0.05). Repertoires do not significantly overlap between individuals (Morisita <0.02). Among iSGS patients, clonality of the TCR repertoire is driven by CD8+ T cells, and iSGS patients possess numerous TCRs targeting viral and intercellular pathogens. High frequency clonotypes do not map to known targets in public datasets.

CONCLUSION

SGS cases do not possess a lower diversity adaptive immune infiltrate when compared with healthy controls. Interestingly, the TCR repertoire in both health and disease contains a restricted number of high frequency clonotypes that do not significantly overlap between individuals. The target of the high frequency clonotypes in health and disease remain unresolved.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:1757-1764, 2024.

Factors Associated with Iatrogenic Laryngeal Injury in Recurrent Respiratory Papillomatosis

OBJECTIVE

To describe iatrogenic laryngeal injury and identify its risk factors in recurrent respiratory papillomatosis (RRP) patients receiving surgical care.

STUDY DESIGN

Case-control.

SETTING

Tertiary care academic hospital in a metropolitan area.

METHODS

Charts of patients with RRP seen at our institution from January 2002 to December 2022 were reviewed. Patients were separated into 2 cohorts based upon whether they experienced any form of iatrogenic laryngeal injury-including anterior commissure synechiae, vocal cord scar, reduced vocal fold pliability, vocal fold motion impairment, and glottic and/or subglottic stenosis. Adjusted logistic regressions were performed to identify factors associated with iatrogenic laryngeal injury.

RESULTS

Of 199 RRP patients, 133 (66.8%) had identifiable iatrogenic laryngeal injury. The most common injuries were anterior commissure synechiae (n = 67; 50.4%) and reduced vocal fold pliability (n = 54; 40.6%). On a multivariate logistic regression, patients with diabetes mellitus (adjusted odds ratio [aOR] [95% confidence interval [CI]]: 2.99 [1.02, 8.79]; P = .04) and who received at least 10 surgeries lifetime (aOR [95% CI]: 14.47 [1.70, 123.19]; P = .01) were at increased risk for iatrogenic laryngeal injury, whereas receiving less than 5 surgeries (aOR [95% CI]: 0.21 [0.09, 0.51]; P < .001) was found to be protective. When treating the lifetime number of surgeries as a continuous variable, a greater number of surgeries was a significant risk factor for iatrogenic laryngeal injury (aOR [95% CI]: 1.32 [1.14, 1.53]; P < .001).

CONCLUSION

These results suggest the importance of strict glucose control for diabetic patients receiving RRP surgical care, and emphasize the clinical need to identify medical therapies to decrease RRP surgical frequency for patients.

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

Level NA Laryngoscope, 2024.

Dysfunctional Epithelial Barrier Is Characterized by Reduced E-Cadherin in Idiopathic Subglottic Stenosis

OBJECTIVES

To aim of the study was to characterize the molecular profile and functional phenotype of idiopathic subglottic stenosis (iSGS)-scar epithelium.

METHODS

Human tracheal biopsies from iSGS scar (n = 6) and matched non-scar (n = 6) regions were analyzed using single-cell RNA sequencing (scRNA-seq). Separate specimens were used for epithelial cell expansion in vitro to assess average growth rate and functional capabilities using transepithelial-electrical resistance (TEER), fluorescein isothiocyanate-dextran flux permeability assay, ciliary coverage, and cilia beating frequency (CBF). Finally, epithelial tight junction protein expression of cultured cells was quantified using immunoblot assay (n = 4) and immunofluorescence (n = 6).

RESULTS

scRNA-seq analysis revealed a decrease in goblet, ciliated, and basal epithelial cells in the scar iSGS cohort. Furthermore, mRNA expression of proteins E-cadherin, claudin-3, claudin-10, occludin, TJP1, and TJP2 was also reduced (p < 0.001) in scar epithelium. Functional assays demonstrated a decrease in TEER (paired 95% confidence interval [CI], 195.68-890.83 Ω × cm2 , p < 0.05), an increase in permeability (paired 95% CI, -6116.00 to -1401.99 RFU, p < 0.05), and reduced epithelial coverage (paired 95% CI, 0.1814-1.766, fold change p < 0.05) in iSGS-scar epithelium relative to normal controls. No difference in growth rate (p < 0.05) or CBF was found (paired 95% CI, -2.118 to 3.820 Hz, p > 0.05). Immunoblot assay (paired 95% CI, 0.0367-0.605, p < 0.05) and immunofluorescence (paired 95% CI, 13.748-59.191 mean grey value, p < 0.05) revealed E-cadherin reduction in iSGS-scar epithelium.

CONCLUSION

iSGS-scar epithelium has a dysfunctional barrier and reduced structural protein expression. These results are consistent with dysfunctional epithelium seen in other airway pathology. Further studies are warranted to delineate the causality of epithelial dysfunction on the downstream fibroinflammatory cascade in iSGS.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:374-381, 2024.

Murine Model of Airway Fibrosis has Anatomic, Physiologic, and Molecular Congruency to Human iSGS

OBJECTIVE

To narrow knowledge gaps in the pathophysiology of idiopathic subglottic stenosis (iSGS) through comparison of a murine subglottic stenosis model with iSGS.

STUDY DESIGN

In vivo animal study.

SETTING

Academic institution.

METHODS

Murine samples/measurements were obtained from mice that underwent chemomechanical injury with a wire brush and bleomycin. Human samples/measurements were obtained from iSGS patients. Anatomic, physiologic, and epithelial molecular data were collected using histology, human peak expiratory flow (PEF) and murine airway conductance, gene expression analysis with quantitative polymerase chain reaction, and protein analysis with quantitative immunohistochemistry.

RESULTS

Anatomic patterns of scars at the subglottis and proximal trachea seen in the murine model are similar to iSGS patients. Subglottic stenosis (SGS) mice had a decrease (P = .0194) in airway conductance compared to healthy controls, similar to a decrease (P = .0001) in predilation PEF versus postdilation in iSGS patients. There was decreased epithelial gene expression of E-cadherin (ECAD) (P < 0.01), occludin (OCLN) (P < .01), and cytokeratin-5 (CK5) (P < .05) and protein expression of ECAD (H/M: P < .001), OCLN (H: P < 0.05, M: P < .001), and CK5 (H: P < .001, M: P < .01) in murine SGS and iSGS versus controls.

CONCLUSION

The murine SGS model shows anatomic, physiologic, and molecular congruency with human iSGS, making it a reasonable model to investigate iSGS. The molecular similarities in epithelial barrier dysfunction suggest it may best be suited to explore epithelial mechanisms of iSGS and therapies directed at epithelial reconstitution. This model provides a foundation to collect data that will improve understanding of iSGS, and, ultimately, translate into more accurate animal models for future use.

Post-extubation Assessment of Laryngeal Symptoms and Severity (PALSS) in the Intensive Care Unit: Protocol of a Prospective Cohort Study

Aims

The Post-extubation Assessment of Laryngeal Symptoms and Severity (PALSS) study systematically evaluates patient symptoms related to endotracheal intubation with mechanical ventilation, assesses laryngeal injury and voice function after extubation, and develops a screening tool to identify patients with clinically important, post-extubation laryngeal injury.

Design

Single-center, prospective observational cohort study conducted in 6 intensive care units (ICU).

Methods

Patients ≥18 years old who are orally intubated and mechanically ventilated in an ICU and meet eligibility criteria will undergo flexible laryngoscopy, with a sample size goal of 300 completed laryngoscopies. Primary outcome measures include signs and symptoms of laryngeal injury, including voice symptoms and alterations in swallowing, measured using the Laryngeal Hypersensitivity Questionnaire-Acute and Voice Symptom Scale questionnaires respectively. Data will be collected within 72 hours post-extubation and at 7-day follow-up or hospital discharge (whichever occurs first). Data will be analyzed using descriptive statistics, regression models, and predictive modeling using machine learning.

Discussion

The findings of this study will describe the clinical signs and symptoms of laryngeal injury post-extubation.

Conclusion

The PALSS study will provide insights for future studies that explore laryngeal injuries using flexible laryngoscopy after endotracheal intubation.

Implications for patient care

Identifying signs and symptoms of laryngeal injury after endotracheal intubation will facilitate the development of a screening tool that will assist in early identification of post-extubation laryngeal injury, and aid in decreasing short- and long-term complications of endotracheal intubation.

Reporting Method

SPIRIT.

Patient or Public Contribution

Patients were study participants; and family members provided informed consent when the patient lacked decision-making capacity.

Localizing Hormone Receptor Expression to Cellular Compartments in Idiopathic Subglottic Stenosis

OBJECTIVES

Idiopathic subglottic stenosis (iSGS) is an unexplained progressive fibrosis of the upper airway. iSGS almost exclusively affects women; as a result, female hormones (estrogen and progesterone) have been proposed to participate in the pathogenesis of iSGS. Our aim was to localize cell-specific gene expression of estrogen receptors (ESR1 and ESR2) and progesterone receptor (PGR) using an established iSGS single-cell RNA sequencing (scRNAseq) cell atlas.

STUDY DESIGN

Ex vivo molecular study of airway scar and healthy mucosa from iSGS patients.

METHODS

An established scRNAseq atlas consisting of 25,974 individually sequenced cells from subglottic scar (n = 7) or matched unaffected mucosa (n = 3) in iSGS patients was interrogated for RNA expression of ESR1, ESR2, and PGR. Results were quantified and compared across cell subsets, then visualized using Uniform Manifold Approximation and Projection (UMAP). Confirmatory protein assessment of endocrine receptors in fibroblasts from iSGS patients (n = 5) was performed via flow cytometry.

RESULTS

The proximal airway mucosa in iSGS patients demonstrates differential expression of endocrine receptors (ESR1, ESR2, PGR). Within airway scar, endocrine receptors are primarily expressed by fibroblasts, immune cells, and endothelial cells. Fibroblasts show strong ESR1 and PGR expression, while immune cells possess RNA for both ESR1 and ESR2. Endothelial cells predominantly express ESR2. Epithelial cells in unaffected mucosa express all three receptors, which are all reduced in airway scar.

CONCLUSIONS

scRNAseq data localized endocrine receptor expression to specific cell subsets. These results provide the foundation for future work interrogating how hormone-dependent mechanisms promote, sustain, or participate in iSGS disease pathogenesis.

LEVEL OF EVIDENCE

NA; Basic science Laryngoscope, 133:3506-3511, 2023.

Factors Associated With Loss of Follow-Up in Transgender Patients Receiving Vocal Therapy

OBJECTIVES

Optimal vocal care for transgender patients necessitates regular follow-up. Factors associated with loss of follow-up in voice patients have never been investigated. In this study, we report a case series of transgender patients seeking vocal care at our institution and compare those who were and were not lost to follow-up.

METHODS

Charts of transgender patients diagnosed with gender dysphoria who sought vocal care at our institution from January 2018 through May 2022 were reviewed. A chronological timeline of each patient's care at our vocal clinic was recorded. Loss of follow-up was defined as instances in which patients were not yet satisfied with their vocal outcomes and expressed interest in scheduling a subsequent visit but had not yet done so. Logistic regressions were performed to identify factors associated with loss of follow-up.

RESULTS

Of 73 patients identified, 59 (80.8%) were assigned male at birth, and 72 (98.6%) were non-Hispanic White. Loss of follow-up occurred in 35 (47.9%) patients. Patients who received vocal surgery were significantly less likely to be lost to follow-up (OR: 0.16 (0.03, 0.79); p = 0.03). The availability of telemedicine options for vocal care was protective against loss of follow-up (OR: 0.09 (0.02, 0.44); p = 0.003). Patients who received other non-voice gender-affirming treatments concomitant to their vocal care were more likely to be lost to follow-up (OR: 4.44 (1.35, 14.59); p = 0.01).

CONCLUSION

Loss of follow-up in transgender patients receiving vocal care is common. Providing telemedicine options and encouraging patients to complete vocal care prior to or after receiving other non-voice gender-affirming treatments may help increase rates of follow-up.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:3061-3067, 2023.

Mapping Genetic Susceptibility to Stenosis in the Proximal Airway

OBJECTIVES

Recent translational scientific efforts in subglottic stenosis (SGS) support a disease model where epithelial alterations facilitate microbiome displacement, dysregulated immune activation, and localized fibrosis. Yet despite recent advances, the genetic basis of SGS remains poorly understood. We sought to identify candidate risk genes associated with an SGS phenotype, investigate their biological function, and identify the cell types enriched for their expression.

METHODS

The Online Mendelian Inheritance in Man (OMIM) database was queried for single gene variants associated with an SGS phenotype. The functional intersections and molecular roles of the identified genes were explored using pathway enrichment analysis (PEA) computational methods. Cellular localization of the candidate risk genes was measured via transcriptional quantification in an established single cell RNA sequencing (scRNA-seq) atlas of the proximal airway.

RESULTS

Twenty genes associated with SGS phenotype were identified. PEA resulted in 24 significantly enriched terms including "cellular response to TGF-β," "epithelial-to-mesenchymal transition," and "adherens junctions." Mapping the 20 candidate risk genes to the scRNA-seq atlas found 3 (15%) genes were enriched in epithelial cells, 3 (15%) in fibroblasts, and 3 (15%) in endothelial cells. 11 (55%) genes were expressed ubiquitously among tissue types. Interestingly, immune cells were not significantly enriched for candidate risk genes.

CONCLUSION

We identify and provide biologic context for 20 genes associated with fibrotic disease of the proximal airway and form the foundation for future detailed genetic study.

LEVEL OF EVIDENCE

N/A Laryngoscope, 133:3049-3056, 2023.

Human Leukocyte Antigen Genotyping of Idiopathic Subglottic Stenosis

OBJECTIVE

Despite recent scientific inquiry, idiopathic subglottic stenosis (iSGS) remains an enigmatic disease. The consistent demographics of the affected population suggest genetic factors may contribute to disease susceptibility. Given the inflammation observed in the affected proximal airway mucosa, we interrogated disease association with human leukocyte antigen (HLA) polymorphisms. Polymorphisms in the HLA locus have previously been shown to influence individuals' susceptibility to distinct inflammatory diseases.

METHODS

High-resolution HLA typing of 37 iSGS patients was compared with 1,242,890 healthy Caucasian controls of European ancestry from the USA National Marrow Donor Program and 281 patients with granulomatosis with polyangiitis (GPA).

RESULTS

Complete HLA genotyping of an iSGS population showed no significant associations when compared to a North American Caucasian control population. Unlike GPA patients, iSGS was not associated with allele DPB1*04:01 nor did allele homozygosity correlate with disease severity.

CONCLUSIONS

There was not a detectable HLA association observed in iSGS. These results support the concept that iSGS possesses a distinct genetic architecture from GPA. If genetic susceptibility exists in iSGS, it likely lies outside the HLA locus.

LEVEL OF EVIDENCE

NA, basic science Laryngoscope, 133:2533-2539, 2023.

Myeloid Phenotypes in Tracheostomy-Associated Granulation Tissue

OBJECTIVE(S)

Tracheostomy-associated granulation tissue is a common, recurrent problem occurring secondary to chronic mucosal irritation. Although granulation tissue is composed of predominantly innate immune cells, the phenotype of monocytes and macrophages in tracheostomy-associated granulation tissue is unknown. This study aims to define the myeloid cell population in granulation tissue secondary to tracheostomy.

METHODS

Granulation tissue biopsies were obtained from 8 patients with tracheostomy secondary to laryngotracheal stenosis. Cell type analysis was performed by flow cytometry and gene expression was measured by quantitative real-time polymerase chain reaction. These methods and immunohistochemistry were used to define the monocyte/macrophage population in granulation tissue and were compared to tracheal autopsy control specimens.

RESULTS

Flow cytometry demonstrated macrophages (CD45+CD11b+) and monocytes (CD45+FSClow SSClow ) represent 23.2 ± 6% of the granulation tissue cell population. The M2 phenotype (CD206) is present in 77 ± 11% of the macrophage population and increased compared to the M1 phenotype (p = 0.012). Classical monocytes (CD45+CD14high CD16low ) were increased in granulation tissue compared to controls (61.2 ± 7% and 30 ± 8.5%, p = 0.038). Eighty-five percent of macrophages expressed pro-inflammatory S100A8/A9 and 36 ± 4% of macrophages co-localized CD169, associated with tissue-resident macrophages. M2 gene expression (Arg1/CD206) was increased in granulation tissue (3.7 ± 0.4, p = 0.035 and 3.5 ± 0.5, p = 0.047) whereas M1 gene expression (CD80/CD86) was similar to controls (p = 0.64, p = 0.3). Immunohistochemistry of granulation tissue demonstrated increased cells co-localizing CD11b and CD206.

CONCLUSIONS

M2 macrophages are the dominant macrophage phenotype in tracheostomy-associated granulation tissue. The role of this cell type in promoting ongoing inflammation warrants future investigation to identify potential treatments for granulation tissue secondary to tracheostomy.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:2346-2356, 2023.

Characterizing the Macrophage Population in Patients With Idiopathic Subglottic Stenosis

OBJECTIVES

Idiopathic subglottic stenosis (iSGS) is characterized by progressive fibrosis and subglottic luminal narrowing. Currently, immune characterization has focused on T-cells; however, macrophages remain largely unexplored. The goals of this study are to characterize the transcriptome of iSGS macrophages and the fibrogenic nature of identifed biomarkers.

STUDY DESIGN

Bioinformatics and in vitro.

METHODS

Human tracheal biopsies from iSGS scar (n = 4), and matched non-scar (n = 4) regions were analyzed using single-cell RNA-seq (scRNA-seq). Immunofluorescence (IF) was performed on rapidly processed autopsies (RPA) and iSGS tracheal resections (n = 4) to co-localize S100A8/9 and CD11b. Collagen gene/protein expression was assessed in iSGS fibroblasts (n = 4) treated with protein S100A8/9 (1000 ng/ml). Macrophages were subclustered to identify distinct subpopulations.

RESULTS

scRNA-seq analysis revealed S100A8/S100A9 (fold change (FC) = 4.1/1.88, p < 0.001) as top differentially expressed genes in iSGS macrophages. IF exhibited increased CD11b+/S100A8/9+ cells in tracheal samples of iSGS versus RPA (26.75% ± 7.08 vs. 0.594% ± 0.974, n = 4, p = 0.029). iSGS fibroblasts treated with S100A8/9 demonstrated increased gene expression of COL1A1 (FC = 2.30 ± 0.45, p = 0.03, n = 4) and COL3A1 (FC = 2.44 ± 0.40, p = 0.03, n = 4). COL1A1 protein assays revealed an increase in the experimental group, albeit not significant, (p = 0.12, n = 4). Finally, macrophage sub clustering revealed one subpopulation as a predominant source of S100A8/S100A9 expression (FC = 7.94/5.47, p < 0.001).

CONCLUSIONS

S100A8/9 is a key biomarker in iSGS macrophages. Although S100A8/9 demonstrates profibrotic nature in vitro, the role of S100A8/9+ macrophages in vivo warrants further investigation.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:2308-2316, 2023.

Sirolimus-eluting airway stent reduces profibrotic Th17 cells and inhibits laryngotracheal stenosis

Laryngotracheal stenosis (LTS) is pathologic fibrotic narrowing of the larynx and trachea characterized by hypermetabolic fibroblasts and CD4+ T cell-mediated inflammation. However, the role of CD4+ T cells in promoting LTS fibrosis is unknown. The mTOR signaling pathways have been shown to regulate the T cell phenotype. Here we investigated the influence of mTOR signaling in CD4+ T cells on LTS pathogenesis. In this study, human LTS specimens revealed a higher population of CD4+ T cells expressing the activated isoform of mTOR. In a murine LTS model, targeting mTOR with systemic sirolimus and a sirolimus-eluting airway stent reduced fibrosis and Th17 cells. Selective deletion of mTOR in CD4+ cells reduced Th17 cells and attenuated fibrosis, demonstrating CD4+ T cells' pathologic role in LTS. Multispectral immunofluorescence of human LTS revealed increased Th17 cells. In vitro, Th17 cells increased collagen-1 production by LTS fibroblasts, which was prevented with sirolimus pretreatment of Th17 cells. Collectively, mTOR signaling drove pathologic CD4+ T cell phenotypes in LTS, and targeting mTOR with sirolimus was effective at treating LTS through inhibition of profibrotic Th17 cells. Finally, sirolimus may be delivered locally with a drug-eluting stent, transforming clinical therapy for LTS.

Idiopathic subglottic stenosis arises at the epithelial interface of host and pathogen

Background

Idiopathic subglottic stenosis (iSGS) is a rare fibrotic disease of the proximal airway affecting adult Caucasian women nearly exclusively. Life-threatening ventilatory obstruction occurs secondary to pernicious subglottic mucosal scar. Disease rarity and wide geographic patient distribution has previously limited substantive mechanistic investigation into iSGS pathogenesis.

Result

By harnessing pathogenic mucosa from an international iSGS patient cohort and single-cell RNA sequencing, we unbiasedly characterize the cell subsets in the proximal airway scar and detail their molecular phenotypes. Results show that the airway epithelium in iSGS patients is depleted of basal progenitor cells, and the residual epithelial cells acquire a mesenchymal phenotype. Observed displacement of bacteria beneath the lamina propria provides functional support for the molecular evidence of epithelial dysfunction. Matched tissue microbiomes support displacement of the native microbiome into the lamina propria of iSGS patients rather than disrupted bacterial community structure. However, animal models confirm that bacteria are necessary for pathologic proximal airway fibrosis and suggest an equally essential role for host adaptive immunity. Human samples from iSGS airway scar demonstrate adaptive immune activation in response to the proximal airway microbiome of both matched iSGS patients and healthy controls. Clinical outcome data from iSGS patients suggests surgical extirpation of airway scar and reconstitution with unaffected tracheal mucosa halts the progressive fibrosis.

Conclusion

Our data support an iSGS disease model where epithelial alterations facilitate microbiome displacement, dysregulated immune activation, and localized fibrosis. These results refine our understanding of iSGS and implicate shared pathogenic mechanisms with distal airway fibrotic diseases.

Posterior Glottic Injury Following Prolonged Intubation in COVID-19 Patients

OBJECTIVE

The objective of this study was to characterize the risk factors for posterior glottic injury (PGI) in patients with coronavirus disease 2019 (COVID-19) who underwent prolonged intubation.

STUDY DESIGN

This was a case-control study designed to assess the risk factors associated with development of PGI in COVID-19 patients who underwent prolonged intubation.

SETTING

This single-center study was conducted at a tertiary care academic hospital in a metropolitan area.

METHODS

We retrospectively reviewed patients who underwent prolonged intubation (≥7 days) for COVID-19 and compared those with PGI to those without. Patient demographics, comorbidities, and intubation characteristics were compared. Factors associated with PGI development among COVID-19 patients were assessed using multivariate regression.

RESULTS

We identified 56 patients who presented with PGI following prolonged intubation for COVID-19 and 60 control patients who underwent prolonged intubation for COVID-19 but did not develop PGI. On univariate analyses, the number of reintubations due to failed extubation efforts was significantly associated with development of PGI (odds ratio [OR], 2.9; 95% CI, 1.4-6.2). On multivariate analyses, patients with cardiovascular disease (OR, 3.3; 95% CI, 1.2-9.0); non-COVID-19 respiratory illnesses, which included obstructive sleep apnea and asthma (OR, 5.9; 95% CI, 2.0-17.8); and diabetes mellitus (OR, 11.6; 95% CI, 3.7-36.6) were more likely to develop PGI.

CONCLUSION

Our results represent the largest case-control study investigating risk factors for PGI in the setting of prolonged intubation specific to COVID-19. Our study suggests a significant role of comorbidities associated with poor wound healing with development of PGI.

Comparative Treatment Outcomes for Idiopathic Subglottic Stenosis: 5-Year Update

The North American Airway Collaborative (NoAAC) previously published a 3-year multi-institutional prospective cohort study showing variation in treatment effectiveness between 3 primary surgical techniques for idiopathic subglottic stenosis (iSGS). In this report, we update these findings to include 5 years of data evaluating treatment effectiveness. Patients in the NoAAC cohort were re-enrolled for 2 additional years and followed using the prespecified published protocol. Consistent with prior data, prospective observation of 487 iSGS patients for 5 years showed treatment effectiveness differed by modality. Cricotracheal resection maintained the lowest rate of recurrent operation (5%), followed by endoscopic resection with adjuvant medical therapy (30%) and endoscopic dilation (50%). These data support the initial observations and continue to provide value to providers and patients navigating longitudinal decision-making. Level of evidence: 2-prospective cohort study.

Phenotypic Epithelial Changes in Laryngotracheal Stenosis

OBJECTIVE

Characterize and quantify epithelium in multiple etiologies of laryngotracheal stenosis (LTS) to better understand its role in pathogenesis.

STUDY DESIGN

Controlled in vitro cohort study.

METHODS

Endoscopic brush biopsy samples of both normal (non-scar) and scar were obtained in four patients with idiopathic subglottic stenosis (iSGS) and four patients with iatrogenic LTS (iLTS). mRNA expression of basal, ciliary, and secretory cell markers were evaluated using quantitative PCR. Cricotracheal resection tissue samples (n = 5 per group) were also collected, analyzed using quantitative immunohistochemistry, and compared with rapid autopsy tracheal samples.

RESULTS

Both iSGS and iLTS-scar epithelium had reduced epithelial thickness compared with non-scar control epithelium (P = .0009 and P = .0011, respectively). Basal cell gene and protein expression for cytokeratin 14 was increased in iSGS-scar epithelium compared with iLTS or controls. Immunohistochemical expression of ciliary tubulin alpha 1, but not gene expression, was reduced in both iSGS and iLTS-scar epithelium compared with controls (P = .0184 and P = .0125, respectively). Both iSGS and iLTS-scar had reductions in Mucin 5AC gene expression (P = .0007 and P = .0035, respectively), an epithelial goblet cell marker, with reductions in secretory cells histologically (P < .0001).

CONCLUSIONS

Compared with non-scar epithelium, the epithelium within iSGS and iLTS is morphologically abnormal. Although both iSGS and iLTS have reduced epithelial thickness, ciliary cells, and secretory cells, only iSGS had significant increases in pathological basal cell expression. These data suggest that the epithelium in iSGS and iLTS play a common role in the pathogenesis of fibrosis in these two etiologies of laryngotracheal stenosis.

SETTING

Tertiary referral center (2017-2020).

LEVEL OF EVIDENCE

NA Laryngoscope, 132:2194-2201, 2022.

Impact of Low-Volume, Low-Pressure Tracheostomy Cuffs on Acute Mucosal Injury in Swine

OBJECTIVE

Tapered low-volume, low-pressure (LVLP) cuffs have been introduced to improve sealing and reduce injury from tracheostomy and endotracheal intubation compared to traditional cylindrical high-volume, low-pressure (HVLP) cuffs. The objective of this study is to develop a swine model of tracheostomy injury and to compare live tissue response following LVLP and HVLP tracheostomy placement.

STUDY DESIGN

In vivo animal study.

SETTING

Academic institution.

METHODS

Swine underwent tracheostomy followed by placement of LVLP and HVLP tracheostomy cuffs at 30 cm H2O. After 24 and 48 hours, tracheal specimens underwent histopathological analysis including cilia, lamina propria and epithelial thickness, and mucosal injury score.

RESULTS

In all cuff contact areas, mean epithelial thickness for both tracheostomy cohorts was decreased compared to control epithelium at 24 and 48 hours (P < .01). HVLP proximal epithelium thickness was decreased at 24 and 48 hours relative to LVLP sections (P < .05). Lamina propria thickness in proximal LVLP sections was less than HVLP sections at 24 hours and 48 hours (P < .05). Mucosal injury score at areas of cuff contact was increased in tracheostomy cohorts relative to controls (P < .001), with HVLP injury score greater than LVLP at the proximal cuff (P < .05).

CONCLUSION

In a swine model, tracheostomy resulted in increased mucosal injury compared to normal tracheal mucosa. LVLP cuffs resulted in less injury than HVLP cuffs, with reduced mucosal inflammation and improved health of epithelium and lamina propria. The wider proximal LVLP cuff demonstrated improved mucosal health compared to the HVLP cylindrical cuff.

Delayed Diagnosis of Idiopathic Subglottic Stenosis

OBJECTIVE

Idiopathic subglottic stenosis (iSGS) is a rare disease, causing life-threatening dyspnea secondary to scarring. Perhaps because it is rarely encountered, there is often a delay in diagnosing iSGS. The objective of this study is to characterize diagnostic delay of iSGS, factors that prolong delay, and its impact on iSGS patients.

STUDY DESIGN

Retrospective chart review.

METHODS

A retrospective chart review of 124 iSGS patients was performed. Times of symptom onset, presentation to otolaryngologist, diagnosis, imaging, pulmonary function testing (PFTs), surgeries, emergency department (ED) visits, and hospitalizations were recorded and univariate analyses were used to identify risk factors for delay.

RESULTS

The median total time to diagnosis from symptom onset was 24.5 months, with time to first presentation of 6.3 months and healthcare delay of 17.8 months. 54.8% of patients were diagnosed with asthma. Earlier presentation to otolaryngologist was associated with shorter healthcare delay and total time to diagnosis (rho = 0.75, rho = 0.99, P < .0001). Earlier CT imaging was correlated to shorter healthcare delay (rho = 0.84, P < .0001) and total time to diagnosis (rho = 0.74, P < .001), while earlier PFTs were correlated to shorter total time to diagnosis alone (rho = 0.71, P = .01). During evaluation, 10.5% (n = 17/124) of patients had ED visits and 13.7% (n = 13/124) patients were hospitalized. Before diagnosis, 7% (9/124) of patients underwent surgeries (including 3% (n = 4) undergoing tracheostomy) and 8% (n = 10) of patients required unplanned urgent endoscopic surgery that may have been avoided with earlier diagnosis.

CONCLUSION

iSGS diagnosis is frequently delayed, resulting in additional surgeries (including tracheostomy), ED visits, and hospitalizations. Further, patients' symptoms are commonly attributed to asthma. Earlier otolaryngologist evaluation, PFTs, and CT imaging may expedite iSGS diagnosis.

LEVEL OF EVIDENCE

4 Laryngoscope, 132:413-418, 2022.

Impact of human immunodeficiency virus status on laryngeal cancer survival and locoregional control

OBJECTIVES

To compare long-term outcomes of laryngeal cancer (LC) in people living with HIV (PLWH) versus uninfected individuals and determine how clinical and viral factors-such as demographics, cancer stage, HIV viral load, and CD4 nadir-contribute to these outcomes.

METHODS

This was a retrospective case-control study of 749 patients seen for LC at a single tertiary care center between 2003 and 2017. Of these, 22 had HIV at the time of LC diagnosis, and they were matched in a 1:4 ratio to uninfected controls based on sex, presence of smoking history, and age at cancer diagnosis. Kaplan-Meier survival curves and Cox proportional hazards models were constructed to identify overall and disease-free survival differences based on HIV status, as well as other clinical and viral factors.

RESULTS

Compared to all uninfected individuals, PLWH were diagnosed with LC approximately 6 years younger (p = .013). 1-, 2-, and 5-year overall survival for PLWH were 86.4% (63.4%-95.4%), 77.3% (53.7%-89.9%), and 65.8% (40.8%-82.2%), respectively following LC diagnosis, and HIV was not significantly associated with overall (HR = 3.34 [0.59-18.79]) or disease-free survival (HR = 2.12 [0.71-6.36]). The incidence rate of locoregional recurrence among PLWH was 541 compared to 371 per 10,000 person-years in controls, which were not significantly different (p = .420). Furthermore, among PLWH, peak viral load and CD4 nadir were not associated with overall or disease-free survival.

CONCLUSION

While previous work has shown that HIV is associated with elevated risk of LC, survival did not differ significantly between PLWH and uninfected individuals in this study.

LEVEL OF EVIDENCE

3.

A survey of patients with laryngotracheal stenosis on future clinical trial design

BACKGROUND/AIMS

Laryngotracheal stenosis is a rare but devastating proximal airway fibrosis that restricts a patient's ability to breathe. Treatment is primarily surgical and to date, there has never been a multi-institutional, randomized, prospective, and interventional clinical trial for a medical therapy to treat laryngotracheal stenosis. Therefore, we aimed to obtain patient feedback to guide successful trial design, recruitment, retention, and for identifying potential barriers to study participation.

METHODS

Over 1000 members of an international laryngotracheal stenosis online support community (the Living with Idiopathic Subglottic Stenosis Facebook group) were sent two questionnaires for a proposed interventional double-blinded, randomized, placebo-controlled clinical trial.

RESULTS

A total of 317 and 558 participants responded to the first and second surveys, respectively. The majority of participants (77%) were willing to consider enrollment, regardless of having a 50% chance of receiving placebo versus treatment (78%). The majority (84%) of participants were willing to travel 200 miles to participate for up to six in-person visits over 50 days. Specific side effects, including anemia/thrombocytopenia (72%) or risk of infection (69.3%) had the greatest impact on clinical trial participation with other side effects (peripheral edema (53%), oral ulcers (51%), and gastrointestinal side effects (41%)) having less impact.

CONCLUSION

Patients with laryngotracheal stenosis possess nuanced insight into their disease and treatment options. As a group, they are extremely motivated for better therapies. Future laryngotracheal stenosis clinical trials should focus on providing excellent side effect -related education and utilizing feedback from online advocacy groups to optimize recruitment and retention.

Prolonged Surgical Interval Following Chemotherapy in a Patient With Idiopathic Subglottic Stenosis (iSGS): Case Report and Brief Review of Literature

Objective:

To report a case of a patient with idiopathic subglottic stenosis (iSGS) who no longer required surgical intervention for her disease following a chemotherapy regimen of carboplatin and doxorubicin for ovarian cancer. A brief review of the literature and discussion on the possible mechanism of action of chemotherapy agents affecting fibrosis is included.

Methods:

Case report and review of literature.

Results:

A 71-year-old Caucasian woman with iSGS was managed with serial endoscopic excision and dilation (n = 5) from 2013 to 2017 with an average dilation interval of 12.3 months. After a course of doxorubicin and carboplatin to treat her ovarian cancer, we observed that her airway stenosis surprisingly stabilized, and has no longer required a surgical dilation for 45 months, which signifies an increase of 33 months when compared to her averaged dilation interval (12.3 months) prior to her second course of chemotherapy.

Conclusion:

We present an iSGS patient whose fibrosis was arrested following carboplatin/doxorubicin treatment. While a single case, a possible mechanism is carboplatin/doxorubicin’s inhibition of pathologic CD4 lymphocytes that propagate laryngotracheal fibrosis. Further investigation of like mechanisms may allow for translation of local agents with inhibitory effects on CD4+ cells and/or fibroblasts as a novel therapy for airway fibrosis.

Laryngeal disorders in people living with HIV

OBJECTIVES

Several studies have shown that HIV infected individuals are at higher risk compared to the general population of developing non-AIDS defining conditions such as some types of cancer, kidney disease, liver disease and others. In this case-control study, we compared the incidence of laryngeal disorders between a treatment-seeking HIV-positive population and uninfected controls. We aimed to investigate whether there are any laryngeal disorders that are overrepresented in HIV-positive individuals.

METHODS

This was a case-control study based on retrospective chart review, comparing the incidence of laryngeal, airway, and swallowing disorders in sixty-nine HIV positive individuals and 4178 HIV negative controls treated between January 1, 2016 and December 31, 2017, at the Johns Hopkins Voice Center.

RESULTS

A majority of HIV-infected patients (59.4%) had at least one diagnosis belonging to the Vocal cord pathology category compared to 48.2% of controls (OR 1.57, p = 0.065). Compared to the entire treatment-seeking population, HIV patients were more likely to present with laryngeal cancer (15.9% vs. 3.4% in controls, OR 5.43, p < 0.001) and chronic laryngitis (17.4% vs. 4.2%, OR 4.79, p < 0.001). Fungal and ulcerative laryngitis were also overrepresented in HIV-positive individuals (OR 9.45, p < 0.001 and 6.29, p < 0.001, respectively). None of the diagnoses categorized as functional voice disorders, swallowing, or airway problems showed a significant difference between groups. Laryngeal papillomatosis, which is an HPV-dependent disease, had similar prevalence in both groups.

CONCLUSIONS

Treatment-seeking HIV-positive patients presenting to a laryngology clinic suffer significantly more often from laryngeal squamous cell carcinoma as well as chronic, fungal, and ulcerative laryngitis compared to HIV-negative individuals.

LEVEL OF EVIDENCE

4.

Corticosteroid Use in Otolaryngology: Current Considerations During the COVID-19 Era

OBJECTIVE

To offer pragmatic, evidence-informed advice on administering corticosteroids in otolaryngology during the coronavirus disease 2019 (COVID-19) pandemic, considering therapeutic efficacy, potential adverse effects, susceptibility to COVID-19, and potential effects on efficacy of vaccination against SARS-CoV-2, which causes COVID-19.

DATA SOURCES

PubMed, Cochrane Library, EMBASE, CINAHL, and guideline databases.

REVIEW METHODS

Guideline search strategies, supplemented by database searches on sudden sensorineural hearing loss (SSNHL), idiopathic facial nerve paralysis (Bell's palsy), sinonasal polyposis, laryngotracheal disorders, head and neck oncology, and pediatric otolaryngology, prioritizing systematic reviews, randomized controlled trials, and COVID-19-specific findings.

CONCLUSIONS

Systemic corticosteroids (SCSs) reduce long-term morbidity in individuals with SSNHL and Bell's palsy, reduce acute laryngotracheal edema, and have benefit in perioperative management for some procedures. Topical or locally injected corticosteroids are preferable for most other otolaryngologic indications. SCSs have not shown long-term benefit for sinonasal disorders. SCSs are not a contraindication to vaccination with COVID-19 vaccines approved by the US Food and Drug Administration. The Centers for Disease Control and Prevention noted that these vaccines are safe for immunocompromised patients.

IMPLICATIONS FOR PRACTICE

SCS use for SSNHL, Bell's palsy, laryngotracheal edema, and perioperative care should follow prepandemic standards. Local or topical corticosteroids are preferable for most other otolaryngologic indications. Whether SCSs attenuate response to vaccination against COVID-19 or increase susceptibility to SARS-CoV-2 infection is unknown. Immunosuppression may lower vaccine efficacy, so immunocompromised patients should adhere to recommended infection control practices. COVID-19 vaccination with Pfizer-BioNTech, Moderna, or Johnson & Johnson vaccines is safe for immunocompromised patients.

Preoperative Briefings and Postoperative Debriefings to Increase Resident Operative Autonomy and Performance

OBJECTIVE

To implement the use of standardized preoperative briefings and postoperative debriefings for surgical cases involving residents in an effort to improve resident autonomy and skill acquisition.

DESIGN

Prospective longitudinal study.

SETTING

Johns Hopkins Department of Otolaryngology-Head and Neck Surgery.

PARTICIPANTS

Resident and attending physicians.

RESULTS

Joint Huddles for Improving Resident Education (JHFIRE) tool was created and successfully implemented by 19 residents and 17 faculty members. Over the course of three data collection periods spanning an academic year, overall scores improved though not statistically significantly in the metrics of Zwisch autonomy, Resident Performance, and Objective Structured Assessment of Technical Skills (OSATS) scores. Female residents were scored significantly higher by attendings than their male counterparts in the assessment of baseline Resident Performance.

CONCLUSIONS

(1) JHFIRE tool implemented a standardized preoperative briefing and postoperative debriefing to improve communication and resident skill acquisition; (2) The tool was accepted and utilized throughout an academic year; (3) Zwisch, Resident Performance, and OSATS scores improved though not significantly.

Quantifying Viral Particle Aerosolization Risk During Tracheostomy Surgery and Tracheostomy Care

Importance

During respiratory disease outbreaks such as the COVID-19 pandemic, aerosol-generating procedures, including tracheostomy, are associated with the risk of viral transmission to health care workers.

Objective

To quantify particle aerosolization during tracheostomy surgery and tracheostomy care and to evaluate interventions that minimize the risk of viral particle exposure.

Design, Setting, and Participants

This comparative effectiveness study was conducted from August 2020 to January 2021 at a tertiary care academic institution. Aerosol generation was measured in real time with an optical particle counter during simulated (manikin) tracheostomy surgical and clinical conditions, including cough, airway nebulization, open suctioning, and electrocautery. Aerosol sampling was also performed during in vivo swine tracheostomy procedures (n = 4), with or without electrocautery. Fluorescent dye was used to visualize cough spread onto the surgical field during swine tracheostomy. Finally, 6 tracheostomy coverings were compared with no tracheostomy covering to quantify reduction in particle aerosolization.

Main Outcomes and Measures

Respirable aerosolized particle concentration.

Results

Cough, airway humidification, open suctioning, and electrocautery produced aerosol particles substantially above baseline. Compared with uncovered tracheostomy, decreased aerosolization was found with the use of tracheostomy coverings, including a cotton mask (73.8% [(95% CI, 63.0%-84.5%]; d = 3.8), polyester gaiter 79.5% [95% CI, 68.7%-90.3%]; d = 7.2), humidification mask (82.8% [95% CI, 72.0%-93.7%]; d = 8.6), heat moisture exchanger (HME) (91.0% [95% CI, 80.2%-101.7%]; d = 19.0), and surgical mask (89.9% [95% CI, 79.3%-100.6%]; d = 12.8). Simultaneous use of a surgical mask and HME decreased the particle concentration compared with either the HME (95% CI, 1.6%-12.3%; Cohen d = 1.2) or surgical mask (95% CI, 2.7%-13.2%; d = 1.9) used independently. Procedures performed with electrocautery increased total aerosolized particles by 1500 particles/m3 per 5-second interval (95% CI, 1380-1610 particles/m3 per 5-second interval; d = 1.8).

Conclusions and Relevance

The findings of this laboratory and animal comparative effectiveness study indicate that tracheostomy surgery and tracheostomy care are associated with significant aerosol generation, putting health care workers at risk for viral transmission of airborne diseases. Combined HME and surgical mask coverage of the tracheostomy was associated with decreased aerosolization, thereby reducing the risk of viral transmission to health care workers.

Endoscopic Resection and Mucosal Reconstitution With Epidermal Grafting: A Pilot Study in Idiopathic Subglottic Stenosis

OBJECTIVE

To describe technical aspects and surgical outcomes of endoscopic resection and mucosal reconstitution with epidermal grafting (ie, the Maddern procedure) in the treatment of idiopathic subglottic stenosis.

STUDY DESIGN

Medical record abstraction.

SETTING

Johns Hopkins Hospital.

METHODS

Retrospective series of 9 adults with idiopathic subglottic stenosis who underwent the Maddern procedure by a single surgeon over a 5-year period. Prespecified outcomes included (1) perioperative outcomes (Clavien-Dindo grade 4/5 complications, need for staged tracheostomy, hospital length of stay), (2) postoperative outcomes (peak expiratory flow rate [PEFR], need for subsequent airway surgery, tracheostomy at follow-up), and (3) patient-reported quality-of-life outcomes (Clinical COPD Questionnaire, Voice Handicap Index-10, Eating Assessment Tool-10, and 12-Item Short Form Version 2). Wilcoxon matched-pairs signed rank test and Kaplan-Meier analysis were performed.

RESULTS

There were no Clavien-Dindo grade 4/5 complications; 2 patients required unplanned staged tracheostomy; and the median length of stay was 3 days. Following endoscopic resection and stent removal, a median of 2 laser resurfacing procedures were required. Two patients developed recurrent stenosis requiring cricotracheal resection (CTR). There were significant improvements in PEFR, Clinical COPD Questionnaire, and Voice Handicap Index-10, without significant difference in Eating Assessment Tool-10. The 12-Item Short Form Version 2 approximated the population norm. Kaplan-Meier analysis demonstrated significant improvement in time to surgery after the final laser resurfacing.

CONCLUSION

The Maddern procedure has a low complication rate and offers durable physiologic improvement in PEFR, limiting need for additional procedures. Risks included need for CTR salvage, temporary tracheostomy, phlegm accumulation, and laryngospasm. It is a surgical option for patients with short dilation intervals who prefer to avoid the risks of CTR.

The Role of Preoperative Briefing and Postoperative Debriefing in Surgical Education

OBJECTIVE

To study the impact of a new preoperative briefing and postoperative debriefing tool on the perceived quality of surgical education and to assess attitudes of residents and attendings regarding this tool.

DESIGN

Surrounding introduction and use of the tool (JHFIRE: Joint Huddles for Improving Resident Education), perceived quality of surgical education was assessed with pre- and postintervention System for Evaluation of Teaching Qualities (SETQ) surveys. Additionally, a postintervention Likert survey regarding the JHFIRE tool itself was completed by residents and faculty.

SETTING

Johns Hopkins University Department of Otolaryngology-Head and Neck Surgery, a tertiary care academic institution.

PARTICIPANTS

All residents and attendings who used the tool were invited to participate. 40 participants (13 residents, 27 attendings) completed the preintervention SETQ. 11 participants (3 residents, 7 attendings, 1 unspecified) completed the postintervention SETQ. For postintervention qualitative assessment of the tool itself, 12 participants (3 residents, 7 attendings, 2 unspecified) provided feedback.

RESULTS

The tool was well-received with large subjective benefit in improving resident surgical education. A total of 88% thought that the time spent on the debriefings was "just right" and 91% planned to make the debriefings a regular part of operative performance assessments. Despite this overwhelmingly positive feedback, there was no overall difference in pre- and postintervention SETQ scores for climate of surgical education in the Department (4.25 ± 0.55 vs. 4.10 ± 0.88, p = 0.63).

CONCLUSIONS

Introduction of 4 item preoperative briefing and 4 item postoperative debriefing checklists was welcomed by both residents and faculty for its ability to shape surgical education in the operating room into a guided discovery model of hands-on education. Overall SETQ scores did not change, but most participants found value in the tool and plan to continue its use.

Characterization of Fibroblasts in Iatrogenic Laryngotracheal Stenosis and Type II Diabetes Mellitus

OBJECTIVES

Iatrogenic laryngotracheal stenosis (iLTS) is the pathological narrowing of the glottis, subglottis, and/or trachea due to scar tissue. Patients with type 2 diabetes mellitus (T2DM) are over 8 times more likely to develop iLTS and represent 26% to 53% of all iLTS patients. In this investigation, we compared iLTS scar-derived fibroblasts in patients with and without T2DM.

STUDY DESIGN

Controlled ex vivo study.

METHODS

iLTS scar fibroblasts were isolated and cultured from subglottic scar biopsies in iLTS patients diagnosed with or without type 2 diabetes (non-T2DM). Fibroblast proliferation, fibrosis-related gene expression, and metabolic utilization of oxidative phosphorylation (OXPHOS) and glycolysis were assessed. Contractility was measured using a collagen-based assay. Metabolically targeted drugs (metformin, phenformin, amobarbital) were tested, and changes in fibrosis-related gene expression, collagen protein, and contractility were evaluated.

RESULTS

Compared to non-T2DM, T2DM iLTS scar fibroblasts had increased α-smooth muscle actin (αSMA) expression (8.2× increased, P = .020), increased contractility (mean 71.4 ± 4.3% vs. 51.7 ± 16% Δ area × 90 minute-1 , P = .016), and reduced proliferation (1.9× reduction at 5 days, P < .01). Collagen 1 (COL1) protein was significantly higher in the T2DM group (mean 2.06 ± 0.19 vs. 0.74 ±.44 COL1/total protein [pg/μg], P = .036). T2DM iLTS scar fibroblasts had increased measures of OXPHOS, including basal respiration (mean 86.7 vs. 31.5 pmol/minute/10 μg protein, P = .016) and adenosine triphosphate (ATP) generation (mean 97.5 vs. 25.7 pmol/minute/10 μg protein, P = .047) compared to non-T2DM fibroblasts. Amobarbital reduced cellular contractility; decreased collagen protein; and decreased expression of αSMA, COL1, and fibronectin. Metformin and phenformin did not significantly affect fibrosis-related gene expression.

CONCLUSION

T2DM iLTS scar fibroblasts demonstrate a myofibroblast phenotype and greater contractility compared to non-T2DM. Their bioenergetic preference for OXPHOS drives their increased contractility, which is selectively targeted by amobarbital.

LEVEL OF EVIDENCE

NA Laryngoscope, 131:1570-1577, 2021.

Identifying Phenotypically Distinct Fibroblast Subsets in Type 2 Diabetes-Associated Iatrogenic Laryngotracheal Stenosis

OBJECTIVE

Iatrogenic laryngotracheal stenosis (iLTS) is the pathologic narrowing of the glottis, subglottis, and/or trachea secondary to intubation or tracheostomy related injury. Patients with type 2 diabetes mellitus (T2DM) are more likely to develop iLTS. To date, the metabolomics and phenotypic expression of cell markers in fibroblasts derived from patients with T2DM and iLTS are largely unknown.

STUDY DESIGN

Controlled in vitro cohort study.

SETTING

Tertiary referral center (2017-2020).

METHODS

This in vitro study assessed samples from 6 patients with iLTS who underwent surgery at a single institution. Fibroblasts were isolated from biopsy specimens of laryngotracheal scar and normal-appearing trachea and compared with controls obtained from the trachea of rapid autopsy specimens. Patients with iLTS were subcategorized into those with and without T2DM. Metabolic substrates were identified by mass spectrometry, and cell protein expression was measured by flow cytometry.

RESULTS

T2DM iLTS-scar fibroblasts had a metabolically distinct profile and clustered tightly on a Pearson correlation heat map as compared with non-T2DM iLTS-scar fibroblasts. Levels of itaconate were elevated in T2DM iLTS-scar fibroblasts. Flow cytometry demonstrated that T2DM iLTS-scar fibroblasts were associated with higher CD90 expression (Thy-1; mean, 95%) when compared with non-T2DM iLTS-scar (mean, 83.6%; P = .0109) or normal tracheal fibroblasts (mean, 81.1%; P = .0042).

CONCLUSIONS

Scar-derived fibroblasts from patients with T2DM and iLTS have a metabolically distinct profile. These fibroblasts are characterized by an increase in itaconate, a metabolite related to immune-induced scar remodeling, and can be identified by elevated expression of CD90 (Thy-1) in vitro.

Quantitative Assessment of the Immune Microenvironment in Patients With Iatrogenic Laryngotracheal Stenosis

OBJECTIVE

Iatrogenic laryngotracheal stenosis (iLTS) is characterized by fibroinflammatory narrowing of the upper airway and is most commonly caused by intubation injury. Evidence suggests a key role for CD4 T cells in its pathogenesis. The objective of this study is to validate emerging multiplex immunofluorescence (mIF) technology for use in the larynx and trachea while quantitatively characterizing the immune cell infiltrate in iLTS. In addition to analyzing previously unstudied immune cell subsets, this study aims to validate previously observed elevations in the immune checkpoint PD-1 and its ligand PD-L1 while exploring their spatial and cellular distributions in the iLTS microenvironment.

STUDY DESIGN

Controlled ex vivo cohort study.

SETTING

Tertiary care center.

METHODS

mIF staining was performed with formalin-fixed, paraffin-embedded slides from 10 patients with iLTS who underwent cricotracheal resection and 10 control specimens derived from rapid autopsy for CD4, CD8, CD20, FoxP3, PD-1, PD-L1, and cytokeratin.

RESULTS

There was greater infiltration of CD4+ T cells, CD8+ T cells, CD20+ B cells, FoxP3+CD4+ Tregs, and FoxP3+CD8+ early effector T cells in the submucosa of iLTS specimens as compared with controls (P < .05 for all). PD-1 was primarily expressed on T cells and PD-L1 predominantly on CD4+ cells and "other" cells.

CONCLUSION

This study leverages the power of mIF to quantify the iLTS immune infiltrate in greater detail. It confirms the highly inflammatory nature of iLTS, with CD4+ cells dominating the immune cell infiltrate; it further characterizes the cellular and spatial distribution of PD-1 and PD-L1; and it identifies novel immunologic targets in iLTS.

Resistin-Like Molecule α Dysregulates Cardiac Bioenergetics in Neonatal Rat Cardiomyocytes

Heart (right) failure is the most frequent cause of death in patients with pulmonary arterial hypertension. Although historically, increased right ventricular afterload has been considered the main contributor to right heart failure in such patients, recent evidence has suggested a potential role of load-independent factors. Here, we tested the hypothesis that resistin-like molecule α (RELMα), which has been implicated in the pathogenesis of vascular remodeling in pulmonary artery hypertension, also contributes to cardiac metabolic remodeling, leading to heart failure. Recombinant RELMα (rRELMα) was generated via a Tet-On expression system in the T-REx 293 cell line. Cultured neonatal rat cardiomyocytes were treated with purified rRELMα for 24 h at a dose of 50 nM. Treated cardiomyocytes exhibited decreased mRNA and protein expression of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) and transcription factors PPARα and ERRα, which regulate mitochondrial fatty acid metabolism, whereas genes that encode for glycolysis-related proteins were significantly upregulated. Cardiomyocytes treated with rRELMα also exhibited a decreased basal respiration, maximal respiration, spare respiratory capacity, ATP-linked OCR, and increased glycolysis, as assessed with a microplate-based cellular respirometry apparatus. Transmission electron microscopy revealed abnormal mitochondrial ultrastructure in cardiomyocytes treated with rRELMα. Our data indicate that RELMα affects cardiac energy metabolism and mitochondrial structure, biogenesis, and function by downregulating the expression of the PGC-1α/PPARα/ERRα axis.

Factors Affecting Dilation Interval in Patients With Granulomatosis With Polyangiitis-Associated Subglottic and Glottic Stenosis

OBJECTIVE

Subglottic stenosis (SGS) is a known complication of granulomatosis with polyangiitis (GPA). We investigated the impact of medical and surgical interventions on the surgical dilation interval and characterized patients with glottic involvement.

STUDY DESIGN

A retrospective chart review of patients with GPA-associated SGS was performed from 2010 to 2019.

SETTING

Tertiary academic medical center.

METHODS

The impact of medical and surgical interventions on dilation interval was assessed. The prevalence of glottic involvement was assessed, and clinical characteristics and outcomes were compared with patients without glottic involvement.

RESULTS

A total of 39 patients with GPA-associated SGS were analyzed. Dilation intervals in patients receiving leflunomide (n = 4; median, 484 days; 95% CI, 405-1099) were greater than in those not receiving leflunomide (median, 155 days; 95% CI, 48-305; P = .033). The surgical technique used did not affect dilation interval. Patients with glottic involvement (n = 13) had a greater incidence of dysphonia (13/13 vs 15/26 [58%], P = .007) and a shorter dilation interval with involvement (median, 91 days; interquartile range, 70-277) versus without involvement (median, 377 days; interquartile range, 175-1148; hazard ratio, 3.38; 95% CI, 2.26-5.05; P < .001). Of 13 patients, 8 (62%) did not have glottic involvement on first presentation.

CONCLUSION

Although GPA is classically thought to affect the subglottis, it also involves the glottis in a subset of patients. These patients have greater complaints of dysphonia and require more frequent surgery. Systemic therapy may increase dilation intervals. In this preliminary study, patients taking leflunomide demonstrated an improvement, highlighting the need for further study of immunosuppression regimens in the treatment of GPA-associated SGS.

Laryngeal Injury and Upper Airway Symptoms After Endotracheal Intubation During Surgery: A Systematic Review and Meta-analysis

Laryngeal injury from intubation can substantially impact airway, voice, and swallowing, thus necessitating multidisciplinary interventions. The goals of this systematic review were (1) to review the types of laryngeal injuries and their patient-reported symptoms and clinical signs resulting from endotracheal intubation in patients intubated for surgeries and (2) to better understand the overall the frequency at which these injuries occur. We conducted a search of 4 online bibliographic databases (ie, PubMed, Embase, Cumulative Index of Nursing and Allied Health Literature [CINAHL], and The Cochrane Library) and ProQuest and Open Access Thesis Dissertations (OPTD) from database inception to September 2019 without restrictions for language. Studies that completed postextubation laryngeal examinations with visualization in adult patients who were endotracheally intubated for surgeries were included. We excluded (1) retrospective studies, (2) case studies, (3) preexisting laryngeal injury/disease, (4) patients with histories of or surgical interventions that risk injury to the recurrent laryngeal nerve, (5) conference abstracts, and (6) patient populations with nonfocal, neurological impairments that may impact voice and swallowing function, thus making it difficult to identify isolated postextubation laryngeal injury. Independent, double-data extraction, and risk of bias assessment followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and the Cochrane Collaboration's criteria. Twenty-one articles (1 cross-sectional, 3 cohort, 5 case series, 12 randomized controlled trials) representing 21 surgical studies containing 6140 patients met eligibility criteria. The mean patient age across studies reporting age was 49 (95% confidence interval [CI], 45-53) years with a mean intubation duration of 132 (95% CI, 106-159) minutes. Studies reported no injuries in 80% (95% CI, 69-88) of patients. All 21 studies presented on type of injury. Edema was the most frequently reported mild injury, with a prevalence of 9%-84%. Vocal fold hematomas were the most frequently reported moderate injury, with a prevalence of 4% (95% CI, 2-10). Severe injuries that include subluxation of the arytenoids and vocal fold paralysis are rare (<1%) outcomes. The most prevalent patient complaints postextubation were dysphagia (43%), pain (38%), coughing (32%), a sore throat (27%), and hoarseness (27%). Overall, laryngeal injury from short-duration surgical intubation is common and is most often mild. No uniform guidelines for laryngeal assessment postextubation from surgery are available and hoarseness is neither a good indicator of laryngeal injury or dysphagia. Protocolized screening for dysphonia and dysphagia postextubation may lead to improved identification of injury and, therefore, improved patient outcomes and reduced health care utilization.

Association of Social Determinants of Health with Time to Diagnosis and Treatment Outcomes in Idiopathic Subglottic Stenosis

OBJECTIVES

To examine whether social determinants of health (SDH) factors are associated with time to diagnosis, treatment selection, and time to recurrent surgical intervention in idiopathic subglottic stenosis (iSGS) patients.

METHODS

Adult patients with diagnosed iSGS were recruited prospectively (2015-2017) via clinical providers as part of the North American Airway Collaborative (NoAAC) and via an online iSGS support community on Facebook. Patient-specific SDH factors included highest educational attainment (self-reported), median household income (matched from home zip code via U.S. Census data), and number of close friends (self-reported) as a measure of social support. Main outcomes of interest were time to disease diagnosis (years from symptom onset), treatment selection (endoscopic dilation [ED] vs cricotracheal resection [CTR] vs endoscopic resection with adjuvant medical therapy [ERMT]), and time to recurrent surgical intervention (number of days from initial surgical procedure) as a surrogate for disease recurrence.

RESULTS

The total 810 participants were 98.5% female, 97.2% Caucasian, and had a median age of 50 years (IQR, 43-58). The cohort had a median household income of $62 307 (IQR, $50 345-$79 773), a median of 7 close friends (IQR, 4-10), and 64.7% of patients completed college or graduate school. Education, income, and number of friends were not associated with time to diagnosis via multivariable linear regression modeling. Univariable multinominal logistic regression demonstrated an association between education and income for selecting ED versus ERMT, but no associations were noted for CTR. No associations were noted for time to recurrent surgical procedure via Kaplan Meier modeling and Cox proportional hazards regression.

CONCLUSIONS

Patient education, income, and social support were not associated with time to diagnosis or time to disease recurrence. This suggests additional patient, procedure, or disease-specific factors contribute to the observed variations in iSGS surgical outcomes.

Chronic Pain Syndromes and Their Laryngeal Manifestations

Importance

Fibromyalgia syndrome (FMS), irritable bowel syndrome (IBS), and chronic fatigue syndrome (CFS) are traditionally considered as distinct entities grouped under chronic pain syndrome (CPS) of an unknown origin. However, these 3 disorders may exist on a spectrum with a shared pathophysiology.

Objective

To investigate whether the clinical presentation of FMS, IBS, and CFS is similar in a population presenting with voice and laryngeal disorders.

Design, Setting, and Participants

This case series was a retrospective review of the medical records and clinical notes of patients treated between January 1, 2016, and December 31, 2017, at the Johns Hopkins Voice Center in Baltimore, Maryland. Patients with at least 1 CPS of interest (FMS, IBS, or CFS) were included (n = 215), along with patients without such diagnoses (n = 4034). Diagnoses, demographic, and comorbidity data were reviewed. Diagnoses related to voice and laryngeal disorders were subdivided into 5 main categories (laryngeal pathology, functional voice disorders, airway problems, swallowing problems, and other diagnoses).

Main Outcomes and Measures

Prevalence and odds ratios of 45 voice and laryngeal disorders were reviewed. Odds ratios (ORs) were calculated by comparing patients with CPS with control patients.

Results

In total, 4249 individuals were identified; 215 (5.1%) had at least 1 CPS and 4034 (94.9%) were control participants. Patients with CPS were 3 times more likely to be women compared with the control group (173 of 215 [80.5%] vs 2318 of 4034 [57.5%]; OR, 3.156; 95% CI, 2.392-4.296), and the CPS group had a mean (SD) age of 57.80 (15.30) years compared with the mean (SD) age of 55.77 (16.97) years for the control group. Patients with CPS were more likely to present with functional voice disorders (OR, 1.812; 95% CI, 1.396-2.353) and less likely to present with laryngeal pathology (OR, 0.774; 95% CI, 0.610-0.982) or airway problems (OR, 0.474; 95% CI, 0.285-0.789).

Conclusions and Relevance

The voice and airway presentation of patients with FMS, IBS, and/or CFS appears to be indistinguishable from each other. This finding suggests that these 3 diseases share upper airway symptoms.

Comparative Treatment Outcomes for Patients With Idiopathic Subglottic Stenosis

Question

What are the outcomes of the 3 most common surgical approaches for idiopathic subglottic stenosis (iSGS)?

Findings

In this cohort study of 810 patients with iSGS who underwent 1 of the 3 most common surgical treatments, 23% of patients underwent a recurrent surgical procedure during the 3-year study period, but recurrence differed by modality (cricotracheal resection, 1%; endoscopic resection with adjuvant medical therapy, 12%; and endoscopic dilation, 28%). Among successfully treated patients, those who underwent cricotracheal resection reported the highest quality of life but the greatest perioperative risk and worst long-term voice outcomes.

Meaning

These results show the feasibility of integrating an engaged rare disease community with a network of surgeons to facilitate rapid and nuanced treatment comparisons; findings may help inform treatment decision-making in iSGS.

Importance

Surgical treatment comparisons in rare diseases are difficult secondary to the geographic distribution of patients. Fortunately, emerging technologies offer promise to reduce these barriers for research.

Objective

To prospectively compare the outcomes of the 3 most common surgical approaches for idiopathic subglottic stenosis (iSGS), a rare airway disease.

Design, Setting, and Participants

In this international, prospective, 3-year multicenter cohort study, 810 patients with untreated, newly diagnosed, or previously treated iSGS were enrolled after undergoing a surgical procedure (endoscopic dilation [ED], endoscopic resection with adjuvant medical therapy [ERMT], or cricotracheal resection [CTR]). Patients were recruited from clinician practices in the North American Airway Collaborative and an online iSGS community on Facebook.

Main Outcomes and Measures

The primary end point was days from initial surgical procedure to recurrent surgical procedure. Secondary end points included quality of life using the Clinical COPD (chronic obstructive pulmonary disease) Questionnaire (CCQ), Voice Handicap Index-10 (VHI-10), Eating Assessment Test-10 (EAT-10), the 12-Item Short-Form Version 2 (SF-12v2), and postoperative complications.

Results

Of 810 patients in this cohort, 798 (98.5%) were female and 787 (97.2%) were white, with a median age of 50 years (interquartile range, 43-58 years). Index surgical procedures were ED (n = 603; 74.4%), ERMT (n = 121; 14.9%), and CTR (n = 86; 10.6%). Overall, 185 patients (22.8%) had a recurrent surgical procedure during the 3-year study, but recurrence differed by modality (CTR, 1 patient [1.2%]; ERMT, 15 [12.4%]; and ED, 169 [28.0%]). Weighted, propensity score–matched, Cox proportional hazards regression models showed ED was inferior to ERMT (hazard ratio [HR], 3.16; 95% CI, 1.8-5.5). Among successfully treated patients without recurrence, those treated with CTR had the best CCQ (0.75 points) and SF-12v2 (54 points) scores and worst VHI-10 score (13 points) 360 days after enrollment as well as the greatest perioperative risk.

Conclusions and Relevance

In this cohort study of 810 patients with iSGS, endoscopic dilation, the most popular surgical approach for iSGS, was associated with a higher recurrence rate compared with other procedures. Cricotracheal resection offered the most durable results but showed the greatest perioperative risk and the worst long-term voice outcomes. Endoscopic resection with medical therapy was associated with better disease control compared with ED and had minimal association with vocal function. These results may be used to inform individual patient treatment decision-making.

Glutamine Inhibition Reduces Iatrogenic Laryngotracheal Stenosis

OBJECTIVE/HYPOTHESIS

Glutamine inhibition has been demonstrated an antifibrotic effect in iatrogenic laryngotracheal stenosis (iLTS) scar fibroblasts in vitro. We hypothesize that broadly active glutamine antagonist, DON will reduce collagen formation and fibrosis-associated gene expression in iLTS mice.

STUDY DESIGN

Prospective controlled animal study.

METHODS

iLTS in mice were induced by chemomechanical injury of the trachea using a bleomycin-coated wire brush. PBS or DON (1.3 mg/kg) were administered by intraperitoneal injection (i.p.) every other day. Laryngotracheal complexes were harvested at days 7 and 14 after the initiation of DON treatment for the measurement of lamina propria thickness, trichrome stain, immunofluorescence staining of collagen 1, and fibrosis-associated gene expression.

RESULTS

The study demonstrated that DON treatment reduced lamina propria thickness (P = .025) and collagen formation in trichrome stain and immunofluorescence staining of collagen 1. In addition, DON decreased fibrosis-associated gene expression in iLTS mice. At day 7, DON inhibited Col1a1 (P < .0001), Col3a1 (P = .0046), Col5a1 (P < .0001), and Tgfβ (P = .023) expression. At day 14, DON reduced Co1a1 (P = .0076) and Tgfβ (P = .023) expression.

CONCLUSIONS

Broadly active glutamine antagonist, DON, significantly reduces fibrosis in iLTS mice. These results suggest that the concept of glutamine inhibition may be a therapeutic option to reduce fibrosis in the laryngotracheal stenosis.

LEVEL OF EVIDENCE

N/A Laryngoscope, 131:E2125-E2130, 2021.

Dysphonia and dysphagia as early manifestations of autoimmune inflammatory myopathy

PURPOSE

While dysphagia is a recognized manifestation of autoimmune inflammatory myopathy, a relationship between myositis and dysphonia or laryngeal pathology is not well-documented. We therefore sought to describe the spectrum of laryngeal disorders present in myositis patients, evaluate whether any specific conditions are overrepresented among these patients compared to a large treatment-seeking population, and examine the clinical course and outcomes of these symptoms.

MATERIALS AND METHODS

This was a retrospective chart review, including all patients seen at the Johns Hopkins Voice Center between January 2016 and December 2017. Demographic data, comorbidities, and laryngeal diagnoses were extracted from the electronic medical record. The charts of patients with myositis were reviewed further to ascertain details of their laryngeal symptoms and myositis disease course. Associations between myositis and dysphonia/dysphagia were evaluated using binary regression and multinomial logistic regression models to adjust for age, sex, race, and smoking status.

RESULTS

Of 4252 patients, sixteen had myositis. Compared to 4236 controls, these patients had significantly higher odds of presenting with muscular voice disorders (adjusted odds ratio (OR*) = 4.503, p* = 0.005) and dysphagia (OR* = 6.823, p* < 0.001). A majority (64.3%, CI:35.6-93.0%) of myositis patients had laryngeal pathology among the presenting symptoms of their myositis. Across all diagnostic categories, there was a non-significant trend towards better outcomes in patients receiving specific interventions for their laryngeal symptoms.

CONCLUSIONS

Muscular voice disorders and dysphagia are significantly overrepresented in myositis patients presenting to a laryngology clinic, and in these patients, both are frequently among the presenting symptoms of myositis.

Multidisciplinary Safety Recommendations After Tracheostomy During COVID-19 Pandemic: State of the Art Review

OBJECTIVE

In the chronic phase of the COVID-19 pandemic, questions have arisen regarding the care of patients with a tracheostomy and downstream management. This review addresses gaps in the literature regarding posttracheostomy care, emphasizing safety of multidisciplinary teams, coordinating complex care needs, and identifying and managing late complications of prolonged intubation and tracheostomy.

DATA SOURCES

PubMed, Cochrane Library, Scopus, Google Scholar, institutional guidance documents.

REVIEW METHODS

Literature through June 2020 on the care of patients with a tracheostomy was reviewed, including consensus statements, clinical practice guidelines, institutional guidance, and scientific literature on COVID-19 and SARS-CoV-2 virology and immunology. Where data were lacking, expert opinions were aggregated and adjudicated to arrive at consensus recommendations.

CONCLUSIONS

Best practices in caring for patients after a tracheostomy during the COVID-19 pandemic are multifaceted, encompassing precautions during aerosol-generating procedures; minimizing exposure risks to health care workers, caregivers, and patients; ensuring safe, timely tracheostomy care; and identifying and managing laryngotracheal injury, such as vocal fold injury, posterior glottic stenosis, and subglottic stenosis that may affect speech, swallowing, and airway protection. We present recommended approaches to tracheostomy care, outlining modifications to conventional algorithms, raising vigilance for heightened risks of bleeding or other complications, and offering recommendations for personal protective equipment, equipment, care protocols, and personnel.

IMPLICATIONS FOR PRACTICE

Treatment of patients with a tracheostomy in the COVID-19 pandemic requires foresight and may rival procedural considerations in tracheostomy in their complexity. By considering patient-specific factors, mitigating transmission risks, optimizing the clinical environment, and detecting late manifestations of severe COVID-19, clinicians can ensure due vigilance and quality care.

Characterization of Geriatric Dysphagia Diagnoses in Age-Based Cohorts

OBJECTIVE

An aging population requires increased focus on geriatric otolaryngology. Patients aged ≥65 years are not a homogenous population, and important physiologic differences have been documented among the young-old (65-74 years), middle-old (75-84), and old-old (≥85). We aim to analyze differences in dysphagia diagnoses and swallowing-related quality-of-life among these age subgroups.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary care laryngology clinic.

SUBJECTS AND METHODS

We identified chief complaint, diagnosis, and self-reported swallowing handicap (Eating Assessment Tool [EAT-10] score) of all new patients aged ≥65 years presenting to the Johns Hopkins Voice Center between April 2015 and March 2017. Dysphagia diagnoses were classified by physiologic etiology and anatomic source. Diagnostic categories and EAT-10 score were evaluated as functions of patient age and sex.

RESULTS

Of 839 new patients aged ≥65 years, 109 (13.0%) reported a chief complaint of dysphagia and were included in this study. The most common dysphagia etiologies were neurologic and esophageal. Most common diagnoses were diverticula (15.6%), reflux (13.8%), and radiation induced (8.3%). Diverticula, cricopharyngeal hypertonicity, and radiation-induced changes were associated with higher EAT-10 score (P < .001). Significant differences by sex were found in anatomic source of dysphagia, as men and women were more likely to present with oropharyngeal and esophageal disease, respectively (P = .023). Dysphagia etiology and EAT-10 score were similar across age subgroups.

CONCLUSION

Important differences among dysphagia diagnosis and EAT-10 score exist among patients aged ≥65 years. Knowledge of these differences may inform diagnostic workup, management, and further investigations in geriatric otolaryngology.

Increased Expression of PD-1 and PD-L1 in Patients With Laryngotracheal Stenosis

OBJECTIVES

Laryngotracheal stenosis (LTS) is a fibrotic condition of the upper airway. Recent evidence suggests dysregulated host immunity plays a role in LTS development and progression. The programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) axis, targeted by paradigm-shifting immunotherapies for cancer treatment, has also recently been implicated in the pathogenesis of fibrotic pulmonary disease. However, a role for the PD-1/PD-L1 axis in the proximal airway fibrosis seen in LTS patients has not been explored.

STUDY DESIGN

Controlled ex vivo study.

METHODS

Expression of PD-1, PD-L1, CD4, and CD8 were evaluated using immunohistochemical staining of cricotracheal resection specimens from postintubation iatrogenic laryngotracheal stenosis (iLTS), idiopathic subglottic stenosis (iSGS) patients, and normal controls derived from rapid autopsy (n = 8 per group). Fibroblasts derived from iLTS scar were also treated with transforming growth factor beta 1 (TGFβ1) and analyzed for PD-L1 expression by quantitative real-time polymerase chain reaction (n = 6).

RESULTS

iLTS specimens exhibited increased expression of PD-1, PD-L1, and CD4 (all P < .0167) compared to controls, whereas iSGS specimens exhibited increased expression of PD-1 and CD4 (P < .0167) compared to controls. PD-1, PD-L1, and CD4 showed periepithelial patterns of expression in both disease cohorts. TGFβ1 treatment of iLTS fibroblasts increased expression of PD-L1 (the cognate ligand for PD-1).

CONCLUSION

Expression of both PD-1 and its ligand PD-L1 are significantly greater in patients with iLTS compared to controls, and PD-1 expression is also elevated in patients with iSGS. Given published evidence implicating the PD-1/PD-L1 axis in pulmonary fibrosis, this suggests a possible role for checkpoint inhibitors targeting the PD-1/PD-L1 axis for the treatment of LTS.

LEVEL OF EVIDENCE

N/A Laryngoscope, 131:967-974, 2021.

Laryngeal Pathologies and Their Associations With Mental Health Disorders

OBJECTIVES

Mental health disorders are very common. Understanding their clinical manifestations in terms of voice and laryngeal disorders (VLD) is important because they constitute a significant proportion of all patients seen by otolaryngology-head and neck surgery. In this study, we examine different mental disorders (MDs) and their presenting symptoms and diagnoses of VLD.

METHODS

Case series study, retrospective chart review of patients seen between January 2016 and December 2017 at the Johns Hopkins Voice Center. Diagnoses, demographic data, and comorbidities were collected. VLD were grouped into categories (laryngeal pathology, functional voice disorders, airway, swallowing, other) for statistical analysis.

RESULTS

Of a total 4,249 patients, 836 patients (19.7%) suffered from at least one MD. Those patients presented more frequently with swallowing problems (24.9% of all diagnoses in MD compared to 21.2% in control group; adjusted odds ratio [aOR] 1.280, 95% confidence interval [CI] 1.107-1.480, P = .001) and less frequently with vocal cord pathology (30.9% of all diagnoses in MD compared to 33.9% in control group, aOR 0.793, 95% CI 0.694-0.907, P = .001). Patients suffering from depression had significantly increased odds for dysphagia (aOR 1.570, 95% CI 1.216-2.026, P = .001). VLD clinical presentation profile was created for every MD studied.

CONCLUSION

Patients suffering from mental health disorders present more frequently with swallowing complaints, in particular for dysphagia. Awareness of this can guide appropriate referrals. Objective laryngeal findings are common in patients with substance abuse disorders. They should be screened with careful diagnostic laryngoscopy.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E231-E239, 2021.

Laryngotracheal Mucosal Surface Expression of Candidate Biomarkers in Idiopathic Subglottic Stenosis

OBJECTIVES

Idiopathic subglottic stenosis (iSGS) is an inflammatory process leading to fibrosis and narrowing of the laryngotracheal airway. There is variability in patient response to surgical intervention, but the mechanisms underlying this variability are unknown. In this pilot study, we measure expression of candidate targets at the mucosal surface of the subglottis in iSGS patients. We aim to identify putative biomarkers for iSGS that provide insights into the molecular basis of disease progression, yield a gene signature for the disease, and/or predict a response to therapy.

STUDY DESIGN

In vitro comparative study of human cells.

METHODS

Levels of candidate transcripts and proteins were measured in healthy and stenotic laryngotracheal tissue specimens taken from the mucosal surface in 16 iSGS patients undergoing endoscopic balloon dilation. Pre- and post-operative pulmonary function test and patient reported voice and breathing outcomes were also assessed. Unsupervised clustering was used to define patient subgroups based on expression profile.

RESULTS

Pulmonary function and voice and breathing outcome metrics demonstrated significant post-operative improvement. Transcript levels of αSMA, CCL2, COL1A1, COL3A1, FN1, IFNG, and TGFB1 and protein levels of CCL2, IFNG, and IL-6 were significantly upregulated in stenotic as compared to healthy tissues. Marked heterogeneity was observed in the patterns of expression of candidate markers across individuals and tissue types. Patient subgroups defined by expression profile did not show a statistically significant difference in dilation interval.

CONCLUSION

Pro-inflammatory and pro-fibrotic pathways are significantly upregulated along the mucosal surface of stenotic laryngotracheal tissues, and CCL2 and IFNG merit further investigation as potential iSGS biomarkers.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:342-349, 2021.

CT Lung Screening in Patients with Laryngeal Cancer

Laryngeal cancer (LC) patients who meet the age and smoking criteria of the U.S. Preventive Services Task Force (USPSTF) for annual CT lung screening were analysed for pulmonary nodules (PN) detection and secondary lung cancer (SLC) diagnosis. This is a retrospective chart review of LC patients treated at Johns Hopkins Hospital from January 2010 to December 2017. The study population included patients who met USPSTF criteria by age and smoking history for annual chest screening and were followed for at least 3 consecutive years. A total of 998 LC patients' records were reviewed, of which 151 met the inclusion criteria. Inadequate follow-up period (37% of excluded cases) was the most common reason for exclusion, followed by not meeting USPSTF age criteria (27% excluded cases). In seventy-eight patients (n = 78, 52% of analysed patients) PN were reported. Nine individuals (6% of analysed patients) were diagnosed with SLC. Age over 70 (p = 0.003) was an independent predictor of malignancy. White race and smoking history over 40 pack-years were positively associated with a pulmonary nodule detection (p = 0.037 and p = 0.044, respectively). The incidence of PN and SLC in patients with LC is high. Many patients with laryngeal cancer meet the formal guidelines for USPSTF screening, and should be screened annually according to evidence-based medicine for the early detection of secondary lung cancers.