Serial office-based steroid injections for treatment of idiopathic subglottic stenosis

Electrospun composite-coated endotracheal tubes with controlled siRNA and drug delivery to lubricate and minimize upper airway injury

Endotracheal Tubes (ETTs) maintain and secure a patent airway; however, prolonged intubation often results in unintended injury to the mucosal epithelium and inflammatory sequelae which complicate recovery. ETT design and materials used have yet to adapt to address intubation associated complications. In this study, a composite coating of electrospun polycaprolactone (PCL) fibers embedded in a four-arm polyethylene glycol acrylate matrix (4APEGA) is developed to transform the ETT from a mechanical device to a dual-purpose device capable of delivering multiple therapeutics while preserving coating integrity. Further, the composite coating system (PCL-4APEGA) is capable of sustained delivery of dexamethasone from the PCL phase and small interfering RNA (siRNA) containing polyplexes from the 4APEGA phase. The siRNA is released rapidly and targets smad3 for immediate reduction in pro-fibrotic transforming growth factor-beta 1 (TGFϐ1) signaling in the upper airway mucosa as well as suppressing long-term sequelae in inflammation from prolonged intubation. A bioreactor was used to study mucosal adhesion to the composite PCL-4APEGA coated ETTs and investigate continued mucus secretory function in ex vivo epithelial samples. The addition of the 4APEGA coating and siRNA delivery to the dexamethasone delivery was then evaluated in a swine model of intubation injury and observed to restore mechanical function of the vocal folds and maintain epithelial thickness when observed over 14 days of intubation. This study demonstrated that increase in surface lubrication paired with surface stiffness reduction significantly decreased fibrotic behavior while reducing epithelial adhesion and abrasion.

Laser Versus Cold Steel for Endoscopic Management of Subglottic Stenosis

OBJECTIVE

Endoscopic management of subglottic stenosis (SGS) includes a wide range of techniques. This 17-year review compares treatment outcomes between carbon dioxide (CO2) laser and cold steel.

STUDY DESIGN

Retrospective chart review.

SETTING

Single tertiary care center.

METHODS

A chart review was performed for all patients undergoing endoscopic treatment of SGS at Cleveland Clinic between July 12, 2000 and September 1, 2017. Data collected included demographics, stenosis etiology, stenosis severity, comorbidities, treatment modality, and airway procedure history. The primary endpoint was repeated treatment-free survival (RTFS) within 2 years using a Kaplan-Meier analysis and Cox proportional hazard model.

RESULTS

A total of 139 patients (median [interquartile range] aged 48.7 [37.8, 57.0] years; 83.4% female) were included in the analysis, with etiologies including idiopathic (56.8%), granulomatosis with polyangiitis (25.2%), and intubation (16.5%). All patients underwent either cold steel (107 patients) or CO2 laser (32 patients) lysis of stenosis with concurrent dilation. RTFS within 2 years was 50.2% for CO2 laser and 31.9% for cold steel (hazard ratio [HR] and 95% confidence interval [CI]: 1.69, 0.96-2.97, P = .07). In patients with no prior airway procedures, there was no difference in RTFS between laser and cold knife (P = .41). However, in patients with prior airway procedures, RTFS was significantly greater in the laser group, even after adjusting for age, smoking history, and stenosis etiology (50.0% vs 16.8%, adjusted HR and CI: 2.82, 1.14-6.98, P = .025).

CONCLUSION

Endoscopic lysis of SGS with CO2 laser should be considered in revision cases.

Idiopathic Subglottic Stenosis in Non-Caucasian Women

Objective

To characterize presentation, disease course, and treatment of idiopathic subglottic stenosis (iSGS) in non-Caucasian women and compare this cohort to the predominantly female, Caucasian patient cohorts identified in the literature.

Study Design

Retrospective review. Results are compared to systematic review of demographics.

Setting

Multiple California institutions from 2008 to 2021.

Methods

Patients with intubation within 2 years of disease or who met exclusion criteria listed in prior publications were excluded. A systematic review of iSGS patient demographics was also completed for comparison.

Results

Of 421 patients with iSGS, 58 self-identified as non-Caucasian women, with 50 ultimately included. Mean age of onset was 45.1 years old (95% confidence interval [CI], 41.5-48.8), and mean age at diagnosis was 47.2 years (95% CI, 43.6-50.7). Mean Charlson comorbidity index was 1.06 (n = 49, 95% CI, 0.69-1.44). At diagnosis, Cotton-Meyer severity scores (documented in n = 45) were Cotton-Myer (CM) I (28.9%), CM II (40%), and CM III (31.1%). Mean age at first endoscopic surgery was 47.7 (95% CI, 44.2-51.3) years. 64% experienced disease recurrence with a median of 11 months between their first and second surgery. Our systematic review identified 60 studies that reported demographic features in patients with iSGS. 95% of pooled patients were Caucasian, while other demographic features were similar to the current cohort.

Conclusion

The non-Caucasian population, almost 14% of this Californian cohort, does not differ from the majority Caucasian population detailed in contemporary literature. This cohort supports the presence of some racial and ethnic heterogeneity in this disease population.

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.

Does Idiopathic Subglottic Stenosis Length and Location Change with Serial Endoscopic Interventions?

OBJECTIVES/HYPOTHESIS

The aim was to assess changes in physical parameters of subglottic stenosis (SGS) following serial endoscopic surgical intervention.

STUDY DESIGN

This was a retrospective chart review.

METHODS

A retrospective review of 52 idiopathic subglottic stenosis (iSGS) patients undergoing multiple endoscopic (excision/dilation) procedures between 2014 and 2022 was completed. Parameters including proximal stenosis distance from the vocal process and total stenosis length collected intraoperatively were compared over serial treatments. Differences between patient variables affecting distances from the vocal process and mean stenosis length were statistically analyzed utilizing nonparametric estimators including the Mann Whitney U, Fisher exact, and linear regression models.

RESULTS

For the cohort of iSGS patients (N = 52), the mean age was 55.1 (±15.1). The patients were predominantly female (96.2%) and Caucasian (84.6%). Patients underwent an average of 3.4 (±1.3) endoscopic procedures for long-term treatment of iSGS (range: 1 to 5 procedures). Patients undergoing a total of two (2) total procedures within the data collection window demonstrated a statistically significant decrease in mean stenosis length between the first and second procedures (p = 0.014). Changes in distance of the stenosis from the glottis was not found to be statistically significant (p = 0.833). There was a statistically significant decrease in mean length of stenosis from the 1st to the 2nd procedure by approximately 0.11 cm (p = 0.0003). No additional statistically significant differences in stenosis length or location were detected.

CONCLUSIONS

Serial endoscopic excision/dilation procedures (the mainstay of iSGS surgical management) do not appear to significantly lengthen intraluminal stenosis nor change the distance of the stenosis from the glottis.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:1769-1772, 2024.

Recombinant Slit2 attenuates tracheal fibroblast activation in benign central airway obstruction by inhibiting the TGF-β1/Smad3 signaling pathway

Airway fibrosis is among the pathological manifestations of benign central airway obstruction noted in the absence of effective treatments and requires new drug targets to be developed. Slit guidance ligand 2-roundabout guidance receptor 1 (Slit2-Robo1) is involved in fibrosis and organ development. However, its significance in airway fibrosis has not yet been reported. The study explored how the recombinant protein Slit2 functions in transforming growth factor-β1 (TGF-β1)-mediated airway fibrosis in vivo and in vitro. In this study, Slit2 expression initially increased in the tracheal granulation tissues of patients with tracheobronchial stenosis but decreased in the fibrotic tissue. In primary rat tracheal fibroblasts (RTFs), recombinant Slit2 inhibited the expression of extracellular matrices such as Timp1, α-SMA, and COL1A2, whereas recombinant TGF-β1 promoted the expression of Robo1, α-SMA, and COL1A2. Slit2 and TGF-β1 played a mutual inhibitory role in RTFs. Slit2 supplementation and Robo1 downregulation inhibited excessive extracellular matrix (ECM) deposition induced by TGF-β1 in RTFs via the TGF-β1/Smad3 pathway. Ultimately, exogenous Slit2 and Robo1 knockdown-mediated attenuation of airway fibrosis were validated in a trauma-induced rat airway obstruction model. These findings demonstrate that recombinant Slit2 alleviated pathologic tracheobronchial healing by attenuating excessive ECM deposition. Slit2-Robo1 is an attractive target for further exploring the mechanisms and treatment of benign central airway obstruction.

The Subglottic Stenosis 6 Questionnaire: A Novel Quality-of-Life Survey Validated to Predict Need for Intervention in Patients With Idiopathic Subglottic Stenosis

BACKGROUND

Idiopathic subglottic stenosis (iSGS) is a recurrent, chronic disease defined by fibroinflammatory narrowing of the subglottic airway. A key challenge in treatment is monitoring disease progression, which may be debilitating and unpredictable in its timing.

RESEARCH QUESTION

Can the Subglottic Stenosis 6 (SGS-6) questionnaire be validated as a novel quality-of-life (QOL) instrument to monitor breathing, disease progression, and disease severity proactively in patients with iSGS?

STUDY DESIGN AND METHODS

Panel data from 51 patients with iSGS were collected from January 2012 through June 2022, representing 1,684 patient encounters including routine office visits and treatment encounters. Subjective QOL scores (including the novel SGS-6 and established RAND-36 and EuroQol Five Dimensions [EQ-5D] Visual Analog Scale) and objective pulmonary function test (PFT) results were collected at each visit. Subjective SGS-6 QOL scores were repeated within 1 week of initial reporting. Panel regression analyses were performed to assess the relationship between SGS-6 scores, PFT results, and a patient's need for intervention. Minimal clinically important differences (MCIDs) for SGS-6 and peak expiratory flow percentage (PEF%) were assessed using receiver operating characteristic (ROC) curve analysis and a patient's need for intervention as the external anchor.

RESULTS

Each one-point increase in SGS-6 score (of a maximum of 27) was associated with a 3.26% decrease in PEF%, a 1.93-point decrease in RAND-36 Physical Health composite score, a 1.27-point decrease in RAND-36 Mental Health composite score, and a 0.88-point decrease in EQ-5D Visual Analog Scale score. The intracorrelation coefficient for the SGS-6 composite score is 0.838 (95% CI, 0.770-0.888). Compared with patient baselines, SGS-6 scores were 4.66 points greater at the time of intervention with an MCID of 2.25 from a patient's baseline. The area under the ROC curve for SGS-6 and a patient's intervention point was 0.81.

INTERPRETATION

iSGS disease severity can be modeled using the SGS-6 questionnaire, offering physicians and patients a potentially new method of tracking disease progression and need for intervention remotely.

Cost-Effectiveness of Steroids for Prolonging the Surgery-Free Interval in Subglottic Stenosis

OBJECTIVES

Repeat endoscopic dilation (ED) in the operating room for subglottic stenosis (SGS) remains an economic burden to patients. The cost-effectiveness (CE) of adjuvant serial intralesional steroid injections (SILSI) to prolong the surgery-free interval (SFI) in SGS patients requiring ED has yet to be studied.

METHODS

Details of the cost of SILSI and ED were received from our tertiary academic center. SFI, cost of intervention, and the effect of SILSI on prolonging SFI were collected from a systematic review by Luke et al. SGS etiologies in the review included idiopathic, iatrogenic, or autoimmune. A break-even analysis, comparing the cost of SILSI alone with the cost of repeat ED, was performed to determine if SILSI injections were cost-effective in prolonging the SFI.

RESULTS

Average extension of the SFI with SILSI was an additional 219.3 days compared to ED alone based on a systematic review of the literature. 41/55 (74.5%) cases did not require further ED once in-office SILSI management began. SILSI administered in a 4-dose series in 3-to-7-week intervals (~$7,564.00) is CE if the reported recurrence rate of SGS requiring ED (~$39,429.00) has an absolute risk reduction (ARR) of at least 19.18% with the use of SILSI. Based on the literature, SILSI prevents ~3 out of every 4 cases of SGS at sufficient follow-up from undergoing repeat ED, resulting in an ARR of ~75%.

CONCLUSIONS

SILSI is economically reasonable if it prolongs the SFI of at least one case of recurrence out of 5. SILSI, therefore, can be CE in extending the interval for surgical ED.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:3436-3442, 2023.

Long-Term Follow-up of 64 Patients With Idiopathic Subglottic Stenosis: Treatment Pathways, Outcomes, and Impact of Serial Intralesional Steroid Injections

OBJECTIVE

To describe treatment pathways and long-term outcomes in 64 patients with idiopathic subglottic stenosis (iSGS), including the impact of serial intralesional steroid injection (SILSI) on degree of stenosis, need for subsequent operation, and patient-reported outcome measures.

METHODS

Retrospective review of 64 female patients with iSGS undergoing varied management approaches, 57 of whom underwent SILSI as at least part of their care. Treatment pathways included SILSI only, endoscopic intervention followed by SILSI only, endoscopic interventions only, endoscopic intervention followed by SILSI followed by need for repeat endoscopic intervention, open surgery, and tracheotomy. Outcomes assessed included subjectively estimated percent airway stenosis, dyspnea index (DI), modified medical research council (MMRC) dyspnea scale, voice handicap index-10 (VHI-10), number of operative and office-based procedures performed, need for subsequent operative intervention, and inter-operative interval.

RESULTS

Treatment pathways included SILSI alone (n = 6), endoscopic intervention(s) followed by SILSI only (n = 31), SILSI followed by additional endoscopic or office-based procedures (n = 16), open surgery (n = 3), and tracheostomy (n = 4). 57 of 64 patients underwent SILSI as at least part of their treatment. Inter-operative interval was increased after starting SILSI. Of patients undergoing SILSI, those with more procedures or shorter inter-operative interval prior to SILSI were more likely to return to the operating room. Estimated stenosis, DI, MMRC, and VHI-10 decreased with SILSI. Stenosis was not correlated with DI, MMRC, or VHI-10, though DI was correlated with both MMRC and VHI-10 score.

CONCLUSION

Of 57 patients undergoing SILSI, 37 did not require further operative intervention. Improvements in inter-operative interval, dyspnea, and voice were observed across patients. Randomized trials to identify which patients may benefit most from SILSI are warranted.

Serial In-Office Steroid Injections for Airway Stenosis: Long-Term Benefit and Cost Analysis

OBJECTIVES

To evaluate the long-term benefit of serial in-office steroid injections (SISI) in the treatment of subglottic and proximal tracheal stenosis (SG/PTS). Evaluate cost of SISI compared to endoscopic dilation (ED).

STUDY DESIGN

Retrospective study and cost analysis.

METHODS

All patients with SGS/PTS with at least two consecutive in-office steroid injections between 2013 and 2021 were evaluated. Patients with less than 2 years of follow-up data after the initial SISI series were excluded. Demographics, etiology of stenosis, total injections performed, time between steroid series, surgery-free interval (SFI) and adverse events were collected. For patients with known surgical history before SISI, pre-SISI SFI was compared. Institutional billing records and the national CMS average reimbursement were evaluated. Total charges for three treatment strategies (ED alone, ED with post-operative SISI and primary intervention with SISI) were also compared.

RESULTS

Forty-nine patients were included; 29 (59%) idiopathic, 11 (22%) traumatic and 9 (18%) rheumatologic. Mean (SD) follow-up time after the first SISI was 3.41 years (1.5), range (2.08-7.25 years). 79% (39/49) did not require additional surgery during the entire follow-up period. The SFI improved from a mean 13.5 months (SD 12.6; range 2-42 months) pre-SISI to a mean (SD) of 42 months (SD 20.2; range 10-87 months) (p < 0.0001) after SISI. Annual average charges for ED alone in our cohort was $15,383.28, compared to $7,070.04 for SISI.

CONCLUSIONS

SISI are an effective treatment for patients with SG/PTS. In-office steroid injections could offer cost savings for the patient.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:2673-2679, 2023.

Impact of Serial Intralesional Steroid Injections on Idiopathic Subglottic Stenosis

OBJECTIVES

Serial intralesional steroid injection (SILSI) has been increasingly used to treat idiopathic subglottic stenosis (iSGS). Prior studies have shown effectiveness, but not in all patients. This multi-institutional study evaluates the effect of SILSI on time to recurrent operation, peak expiratory flow (PEF), and dyspnea.

METHODS

Post-hoc secondary analysis of the North American Airway Collaborative data were performed to evaluate the outcomes of iSGS patients undergoing and not undergoing SILSI. The primary outcome was time to recurrent operation, evaluated using Kaplan-Meier curves and Cox regression analysis. Secondary outcomes were change in PEF and clinical chronic obstructive pulmonary disease questionnaire (CCQ) score. Within patients undergoing SILSI, demographics, time from last procedure, and PEF at initiation of SILSI were evaluated to determine the effect on recurrence.

RESULTS

Two hundred and ninety patients were included, 238 undergoing endoscopic dilation alone and 52 undergoing dilation and SILSI. No differences in baseline characteristics were observed. There was no difference in time to recurrence (hazard ratio: 0.64; p = 0.183). There were no differences in PEF or CCQ across the 2.5-year study period. Among 52 patients undergoing SILSI, PEF at the time of starting SILSI did not affect recurrence (χ2  = 0.09, p = 0.77).

CONCLUSION

Patients undergoing and not undergoing SILSI had similar times to recurrence, PEF, and CCQ. Factors predicting recurrence among patients undergoing SILSI were not identified. These results support a randomized controlled trial with a uniform SILSI protocol to quantify the effects of SILSI on objective and subjective outcomes and help determine which iSGS patients benefit most.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:2255-2263, 2023.

A Novel Trans-Tracheostomal Retrograde Inhalation Technique Increases Subglottic Drug Deposition Compared to Traditional Trans-Oral Inhalation

Subglottic stenosis represents a challenging clinical condition in otolaryngology. Although patients often experience improvement following endoscopic surgery, recurrence rates remain high. Pursuing measures to maintain surgical results and prevent recurrence is thus necessary. Steroids therapy is considered effective in preventing restenosis. Currently, however, the ability of trans-oral steroid inhalation to reach and affect the stenotic subglottic area in a tracheotomized patient is largely negligible. In the present study, we describe a novel trans-tracheostomal retrograde inhalation technique to increase corticosteroid deposition in the subglottic area. We detail our preliminary clinical outcomes in four patients treated with trans-tracheostomal corticosteroid inhalation via a metered dose inhaler (MDI) following surgery. Concurrently, we leverage computational fluid-particle dynamics (CFPD) simulations in an extra-thoracic 3D airway model to gain insight on possible advantages of such a technique over traditional trans-oral inhalation in augmenting aerosol deposition in the stenotic subglottic region. Our numerical simulations show that for an arbitrary inhaled dose (aerosols spanning 1–12 µm), the deposition (mass) fraction in the subglottis is over 30 times higher in the retrograde trans-tracheostomal technique compared to the trans-oral inhalation technique (3.63% vs. 0.11%). Importantly, while a major portion of inhaled aerosols (66.43%) in the trans-oral inhalation maneuver are transported distally past the trachea, the vast majority of aerosols (85.10%) exit through the mouth during trans-tracheostomal inhalation, thereby avoiding undesired deposition in the broader lungs. Overall, the proposed trans-tracheostomal retrograde inhalation technique increases aerosol deposition rates in the subglottis with minor lower-airway deposition compared to the trans-oral inhalation technique. This novel technique could play an important role in preventing restenosis of the subglottis.

The Effect of Subglottic Steroid injection on Blood Glucose in a Cohort of Patients With Subglottic Stenosis

OBJECTIVE

The objective of this work was to assess the effect of a single intralesional subglottic steroid injection on fasting blood glucose over 7 days in a cohort of patients with subglottic stenosis.

METHODS

A prospective cohort study of patients undergoing intralesional steroid injections at a tertiary academic center. Patients had baseline bloodwork performed, including fasting blood glucose (FBG), and hemoglobin A1C levels. Demographic data and risk factors were collected. Fasting capillary glucose (FCG) was measured using a capillary glucometer and performed by patients daily from days 0 to 7 after a single injection of Triamcinolone into the subglottic airway. Data were analyzed using descriptive and comparative statistics.

RESULTS

Eleven patients were enrolled, and 10 completed data collection over 7 days. All were female, with a mean age of 52.6 years (SD 17.5). Two patients were diabetic (non-insulin dependent). There was a statistically significant increase in FCG on day 1 post-injection (mean = 122.4 mg/dl compared to 100.7 mg/dl) that normalized for all patients within 24-72 h. The mean increase in FCG was 21.5% (SD 22.5%) of the initial value for the cohort. The diabetic group had statistically significant higher glucose values on day 1 compared to the non-diabetic group (146.5 mg/dl compared to 117.0 mg/dl).

CONCLUSION

A single subglottic steroid injection appears to cause a transient increase in FCG 1 day post injection, which resolves after 24-72 h and can be more pronounced in diabetic patients.

LEVEL OF EVIDENCE

4 Laryngoscope, 2022.

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.

Serial Intralesional Steroid Injection for Subglottic Stenosis: Systemic Side Effects and Impact on Surgery-Free Interval

Objectives

In-office serial intralesional steroid injections (SILSIs) have become a commonly used treatment for subglottic stenosis. We characterized the impact of SILSIs on the time between operating room visits and incidence of glucocorticoid systemic side effects.

Study Design

Retrospective case series.

Setting

Academic tertiary care center.

Methods

All patients with subglottic stenosis receiving SILSIs at 1 institution from 2016 to 2020 were included. Surgery-free interval was compared using paired t tests. Side effect incidence was calculated with Kaplan-Meier methodology for visualization.

Results

Nineteen patients and 207 procedures were included. The majority of patients were White (95%) and female (95%) and had idiopathic subglottic stenosis (53%). Mean surgery-free interval for all patients was 8.7 months (95% CI, 5.6-11.8) before initiating SILSIs. Of 11 patients with calculable surgery-free interval, 10 experienced improvement, with a mean surgery-free interval increase of 4.6 months (95% CI, 2.4-6.7). Seven patients have not required surgery since initiation of SILSIs, with a mean follow-up time of 28 months (95% CI, 25-31). Noncutaneous systemic side effects occurred at a mean 3.2 months (95% CI, 2.4-4.0) from first injection and included Cushing’s syndrome, increased intraocular pressure, central serous chorioretinopathy, and new insulin requirement in the setting of diabetes.

Conclusions

Ninety-one percent of patients who initiated SILSIs and had a subsequent return to the operating room experienced a mean 4.6-month increase in surgery-free interval. Systemic side effects of glucocorticoids occurred in 32% of patients after initiating SILSIs. This should be considered in preprocedure counseling and side effect monitoring during treatment.

Estimations of Laryngotracheal Stenosis After Mechanical Ventilation: A Cross-Sectional Analysis

OBJECTIVES/HYPOTHESIS

To estimate the incidence of laryngotracheal stenosis among adults after intubation.

STUDY DESIGN

Cross-sectional analysis.

METHODS

We used the Nationwide Readmission Database to examine adult patients readmitted within 45 days after admission for mechanical ventilation. Those with a diagnosis of laryngotracheal stenosis or tracheostomy dependence on their index admission were excluded. Patient demographics, associated comorbidities, and intubation lengths were compared among those with and without a diagnosis of airway stenosis at readmission.

RESULTS

An estimated 624,918 patients met inclusion with a mean age of 59 years (standard error = 0.2). There were 1,230 patients readmitted within 45 days and diagnosed with laryngeal (N = 362) or tracheal stenosis (N = 920) estimating an incidence of 1.98 per 1,000 discharges. Compared with those without a diagnosis of airway stenosis, those with stenosis were younger (57 vs. 59 years, P < .001), more often female (62% vs. 45%, P < .001) and frequently intubated for >96 hours (47% vs. 32%, P < .001). Additionally, a history of respiratory failure, pneumonia, obesity, gastroesophageal reflux disease, and chronic steroid use were also more common among patients with stenosis. Multiple logistic regression analysis identified a decreased risk of stenosis with advancing age while an increased risk was associated strongest for females (odds ratio [OR]: 1.96, 95% confidence interval [CI]: 1.58-2.44, P < .001) and those with chronic steroid use (OR: 2.69, 95% CI: 1.80-4.02, P < .001).

CONCLUSION

The incidence of laryngotracheal stenosis after intubation in adults is rare but is associated with female gender and younger age.

LEVEL OF EVIDENCE

N/A Laryngoscope, 2021.

Multi-disciplinary management of patients with benign airway strictures: A review

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

Down-Regulation of a Profibrotic Transforming Growth Factor-β1/Cellular Communication Network Factor 2/Matrix Metalloprotease 9 Axis by Triamcinolone Improves Idiopathic Subglottic Stenosis

Idiopathic subglottic stenosis (iSGS) is a progressive fibrotic disease characterized by life-threatening airway narrowing. Although the molecular underpinnings are unknown, previous reports showing that subglottic serial intralesional steroid injections (SILSIs) improve clinical outcomes suggest a steroid-sensitive pathway in iSGS. Herein, a prospective study was conducted to determine the changes in profibrotic markers during SILSI to identify steroid-sensitive profibrotic drivers. Seven newly diagnosed patients with iSGS were recruited for SILSI. Subglottic biopsies before and after SILSI treatments were evaluated for histologic and molecular markers by confocal microscopy and RT-qPCR. At baseline, iSGS subglottises contained abundant vimentin-positive/α-smooth muscle actin-negative fibroblasts, intermingled with a matrix of fibronectin and types I and VI collagen. Transforming growth factor (TGF)-β1 was up-regulated primarily in glandular epithelium. Cellular communication network factor 2 (CCN2) was mainly up-regulated in stromal fibroblasts surrounding TGF-β1-positive glandular structures. SILSI improved iSGS by reducing fibroblast infiltration and increasing matrix remodeling. Mechanistically, SILSI counteracted the effects of TGF-β1 by inducing matrix metalloprotease 9 (MMP9) expression while repressing CCN2 expression, without affecting TGFβ1 levels. Treatment of primary iSGS-derived fibroblasts with TGF-β1 recapitulated aspects of the disease in vivo, demonstrating that the induction in CCN2 and repression of MMP9 are caused by changes in histone acetylation induced by TGF-β1. Triamcinolone counteracted the coregulation of these genes by impairing SMAD2/3 binding to promoter regions, and not through histone acetylation. In conclusion, this study shows that SILSI counteracts a dysregulated TGF-β1/CCN2/MMP9 axis involved in iSGS development.

Efficacy of Office-Based Intralesional Steroid Injections in the Management of Subglottic Stenosis: A Systematic Review

OBJECTIVE

To determine the efficacy of office-based intralesional steroid injections (ILSI) as a management therapy for adult subglottic stenosis (SGS).

DATA SOURCES

A systematic review was completed using PubMed and Science Direct for office-based management of SGS due to various etiologies.

REVIEW METHODS

The primary end point measured was a change in surgery free interval (SFI) between endoscopic procedures due to office-based serial ILSI. The secondary end point was to determine what percentage of patients did not require further operative intervention for SGS maintenance therapy after changing management to office-based serial ILSI.

RESULTS

We identified 187 abstracts, 4 of which were included in the analysis. The total number of participants was 55. The mean age was 50.4, and 78.1% were women. The etiologies were as follows: idiopathic (58.2%), postintubation/tracheotomy (29.1%), and autoimmune (12.7%). The SFI was reported in 3 of the 4 studies. The reported mean pre-ILSI SFI was 362.9 days and the post-ILSI SFI was 582.2 days. The secondary outcome was reported in 3 of the 4 studies. Forty-one of the 55 patients (74.5%) did not require further operative intervention during the duration of the study.

CONCLUSION

This review explored office-based ILSI as a potential treatment option for patients with SGS. The limited data presented found ILSI significantly lengthened SFI, potentially reducing surgical burden. In addition, ILSI was found to be safe with few reported side effects.

Vocal Fold Steroid Injection for Benign Vocal Lesions in Professional Voice Users

OBJECTIVES

Current treatments for benign vocal lesions consist mainly voice therapy and phonomicrosurgery. However, these options are not always suitable for professional voice users because of their tight performance schedule and limited time for voice rest. This study investigated vocal fold steroid injection (VFSI) as an alternative treatment.

STUDY DESIGN

Matched case series.

METHODS

We retrospectively enrolled 28 professional voice users (i.e., singers, actors and news anchors) who received VFSI for vocal nodules and polyps in an office setting of a tertiary teaching hospital. Outcomes were evaluated using videolaryngostroboscopy (VLS), the 10-item Voice Handicap Index (VHI-10), maximum phonation time, and acoustic and perceptual analyses before and 1 month after VFSI. Study results were compared with 56 patients of nonprofessional voice users (i.e., routine or high occupational vocal demands), matched in a 1:2 ratio by age, sex, and treatment date.

RESULTS

After VFSI, VLS revealed substantial lesion resolution in 82% professional voice users. One professional voice user developed a self-limited vocal fold hematoma after VFSI. VHI-10 scores in the professional group decreased from 21 to 14 points, compared with 23 to 16 points in the non-professional group, demonstrating a significant within-group effect (P < 0.01, GEE) and a nonsignificant between-group effect (P = 0.86). Other outcomes also improved significantly after VFSI (P < 0.05), without significant differences between the two groups.

CONCLUSION

VFSI can be an effective and safe alternative treatment for professional voice users with benign vocal lesions.

Reliability of peak expiratory flow percentage compared to endoscopic grading in subglottic stenosis

OBJECTIVE

To determine the reliability of pulmonary function testing compared to endoscopic grading in the assessment of subglottic stenosis.

METHODS

Consecutively treated patients with subglottic stenosis at a tertiary care specialty hospital from 2009 to 2019 were identified. Two fellowship-trained laryngologists and two otolaryngologists blinded to clinical history reviewed laryngo tracheoscopic examinations and assessed the degree of stenosis using the Cotton-Myer grading system (% stenosis). Nine full flow-volume loops were performed at the time of each exam.

RESULTS

The endoscopic images of 45 subjects were graded for degree of stenosis and the spirometry data were analyzed. The kappa values for Cotton-Myer grade overall was 0.37, grade I was -0.103, grade II was 0.052, and grade III was 0.045. The overall intraclass correlation of the physician grading of estimated percent obstruction (% stenosis) was 0.712 (P < .01) whereas the overall intraclass correlation for PEF% was 0.96 (P < .01). Within each Cotton-Myer grade, the intraclass correlation for % stenosis was 0.45 (P = .02) for grade I, 0.06 (P = .30) for grade II, and 0.16 (P = .03) for grade III. The intraclass correlation for PEF% for grade I was 0.97 (P < .01), grade II was 0.92 (P < .01), and grade III was 0.96 (P < .01).

CONCLUSION

Cotton-Myer grading and estimating percent obstruction (% stenosis) for adult subglottic stenosis showed poor reliability as an assessment tool compared to the excellent intraclass correlation seen with pulmonary function tests within each Cotton-Myer grade subgroup. We recommend pulmonary function testing, specifically PEF% because it is a normalized value, for the assessment and management of subglottic stenosis.

LEVEL OF EVIDENCE

4.

Pain Experience and Tolerance of Awake In-Office Upper Airway Procedures: Influencing Factors

OBJECTIVES/HYPOTHESIS

Awake, unsedated in-office upper airway procedures are performed frequently and have high completion rates, yet less is known about the patients' pain experience and potentially influencing factors. It is also unclear if patients' pain experiences become worse with repeated procedures. We identified procedure- and patient-related factors that might influence procedural completion and pain scores.

STUDY DESIGN

Retrospective chart review.

METHODS

Pre-, intra-, and post-procedure pain scores were collected prospectively for awake unsedated upper airway procedures performed at a single institution over a 5-year period. Patient factors reviewed were demographics, body mass index, psychiatric and/or pain diagnosis, and related medications. Procedure factors reviewed were procedure type, route, side, and performance of the same procedure multiple times. Patients reported their pain level before, during, and after the procedure using a standard 0 to 10 scale. Maximum pain score change (PΔmax), or the difference between highest and lowest reported pain levels, was calculated. Descriptive and multivariate analyses were performed.

RESULTS

Procedure completion was 98.7% for 609 first time patients and 99.0% in 60 patients undergoing 292 repeat procedures. PΔmax did not covary with age, gender, or BMI. PΔmax covaried with pain and psychiatric conditions and associated medications. PΔmax was highest for injection medialization and lowest for tracheoscopy. PΔmax decreased over time for those undergoing multiple identical procedures.

CONCLUSIONS

Procedures were performed with a very high completion rate and low pain scores. Age, sex, and BMI did not affect pain experience. A combination of pain and psychiatric conditions did. Injection medialization had the highest PΔmax and tracheoscopy the lowest.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E1580-E1588, 2021.

Development of a Bioinspired, Self-Adhering, and Drug-Eluting Laryngotracheal Patch

OBJECTIVES/HYPOTHESIS

Novel laryngotracheal wound coverage devices are limited by complex anatomy, smooth surfaces, and dynamic pressure changes and airflow during breathing. We hypothesize that a bioinspired mucoadhesive patch mimicking how geckos climb smooth surfaces will permit sutureless wound coverage and also allow drug delivery.

STUDY DESIGN

ex-vivo.

METHODS

Polycaprolactone (PCL) fibers were electrospun onto a substrate and polyethylene glycol (PEG) - acrylate flocks in varying densities were deposited to create a composite patch. Sample topography was assessed with laser profilometry, material stiffness with biaxial mechanical testing, and mucoadhesive testing determined cohesive material failure on porcine tracheal tissue. Degradation rate was measured over 21 days in vitro along with dexamethasone drug release profiles. Material handleability was evaluated via suture retention and in cadaveric larynges.

RESULTS

Increased flocking density was inversely related to cohesive failure in mucoadhesive testing, with a flocking density of PCL-PEG-2XFLK increasing failure strength to 6880 ± 1810 Pa compared to 3028 ± 791 in PCL-PEG-4XFLK density and 1182 ± 262 in PCL-PEG-6XFLK density. The PCL-PEG-2XFLK specimens had a higher failure strength than PCL alone (1404 ± 545 Pa) or PCL-PEG (2732 ± 840). Flocking progressively reduced composite stiffness from 1347 ± 15 to 763 ± 21 N/m. Degradation increased from 12% at 7 days to 16% after 10 days and 20% after 21 days. Cumulative dexamethasone release at 0.4 mg/cm² concentration was maintained over 21 days. Optimized PCL-PEG-2XFLK density flocked patches were easy to maneuver endoscopically in laryngeal evaluation.

CONCLUSIONS

This novel, sutureless, patch is a mucoadhesive platform suitable to laryngeal and tracheal anatomy with drug delivery capability.

LEVEL OF EVIDENCE

NA Laryngoscope, 131:1958-1966, 2021.

Idiopathic Subglottic Stenosis: An Institutional Review of Outcomes With a Multimodality Surgical Approach

OBJECTIVES

This article reports on a unique cohort of patients with idiopathic subglottic stenosis spilt fairly equally between endoscopic and open surgical approaches. Patients' sequence of operations and reinterventions over time are outlined, offering insight to improve surgical counseling and allow for informative, autonomous patient decision making.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary care academic center.

METHODS

Cases of consecutive adults with idiopathic subglottic stenosis managed surgically over a 12-year period (January 2006-December 2017) were retrospectively reviewed. Surgical workflow, complications, and outcomes, including reinterventions and tracheotomy dependence, are reported.

RESULTS

Seventy-two patients (71 women; mean age, 50.4 years) with idiopathic subglottic stenosis requiring surgical airway intervention were identified. Six patients underwent tracheotomy prior to attempt at airway stenosis surgery. Initial surgical approach thereafter included endoscopic (73.5%, n = 53) and open (26.4%, n = 19) procedures. Thirty-one patients underwent cricotracheal resection; the reintervention rate was 22.5%. Sixty patients underwent 147 endoscopic procedures; the reintervention rate was 75.5%, and the mean time between dilations was 83 weeks (range, 5-402). Two (2.8%) patients remain tracheotomy dependent. Adverse events were significantly higher in the cricotracheal group, especially with respect to dysphonia and temporary gastrostomy tube placement (P < .01).

CONCLUSIONS

Endoscopic and open surgical airway intervention can be employed successfully to avoid tracheotomy dependence and maintain airway patency; however, multiple procedures are usually required, regardless of surgical approach. Cricotracheal reintervention rates are lower than endoscopic dilation but with increased morbidity. Quality-of-life outcomes should be clearly discussed with patients before deciding on a surgical management strategy.

Voice-Related Quality of Life Is Associated with Postoperative Change in Subglottic Stenosis

OBJECTIVES

To characterize the impact of subglottic stenosis (SGS) on voice-related quality of life (V-RQOL) and quantify the effect of treatment on voice outcomes.

STUDY DESIGN

Case series.

METHODS

Retrospective review of SGS patients treated from 1996 to 2018 at a single institution to assess for 1) V-RQOL association with individual patient cumulative treatment number and 2) V-RQOL correlation with treatment type, time between treatments, and degree of stenosis. Analysis included both parametric and nonparametric statistical comparison across treatment types and multivariable and univariate linear regression.

RESULTS

Sixty-one patients, predominantly white (93%) and female (93%), were included. Etiology of SGS included idiopathic (61%), iatrogenic (16%), granulomatosis with polyangiitis (16%), and other (7%). The plurality of patients had four or more treatments (44%), with the remainder having one (28%), two (13%), or three treatments (15%). Analysis of change between pre- and postoperative V-RQOL scores was completed for 130 treatments. These included dilation with laser incision (52%), in-office injection (34%), dilation without division (8%), cricotracheal resection (1%), and all other treatment (8%). For every 10% improvement in airway caliber postoperatively, there was a 1.3-point improvement in calculated V-RQOL (r = 0.27, P = .02). After adjustment for treatment type, age, sex, and SGS etiology, this association held (beta = 1.5, P = .02). Change in V-RQOL was not associated with treatment type, treatment number, or time between treatments.

CONCLUSION

Patients with subglottic stenosis who have greater degree of change in airway caliber experience greater improvement in V-RQOL scores following treatment. V-RQOL scores are not associated with treatment type or time between individual treatments.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:360-365, 2021.

Idiopathic Subglottic Stenosis during Pregnancy: A Support Group Survey

OBJECTIVES

(1) To determine how pregnancy affects idiopathic subglottic stenosis (iSGS) symptoms. (2) To determine treatments utilized (including operating room (OR) and in-office procedures) for iSGS before, during, and after pregnancy.

METHODS

A 24-question survey was distributed to an international iSGS support group to assess the patient experience among individuals who have been pregnant with diagnosis of iSGS. Descriptive statistics and chi² analyses were completed.

RESULTS

A total of 413 iSGS patients participated; 84.7% (n = 350) of patients were diagnosed prior to menopause. A total of 25.5% patients reported being pregnant when they had airway stenosis; 71.1% of those reported more severe airway symptoms during pregnancy. The proportion of patients that reported requiring ≥1 OR interventions (microlaryngoscopy and bronchoscopy, laser, balloon dilation, or steroid injection) before, during and after pregnancy was the following, respectively: 37.3%, 35.6%, 51.3%. Whereas the proportion of patients that reported requiring ≥1 in-office interventions (awake balloon dilation or steroid injection) before, during and after pregnancy was the following, respectively: 13.6%, 11.8%, 15.8%. Number of pregnancies and age of diagnosis was not related to severity of symptoms or requiring more airway interventions (P > .05).

CONCLUSIONS

This survey reveals worsening of symptoms during pregnancy, however, this did not lead to increase in operative or clinic interventions to improve airway symptoms during pregnancy. Future avenues for research include optimizing management of airway symptoms during pregnancy to limit OR-based interventions.

LEVEL OF EVIDENCE

Level IV.

Proteomic and Genomic Methylation Signatures of Idiopathic Subglottic Stenosis

OBJECTIVE

Idiopathic subglottic stenosis (iSGS) is a chronic inflammatory condition that causes dyspnea and affects middle-aged women of White race and non-Latino or Hispanic ethnicity. To better characterize its phenotype and pathogenesis, we assessed the proteomic and genomic methylation signatures of subglottic tissue collected from iSGS patients compared to controls.

STUDY DESIGN

Molecular analysis of clinical biospecimens.

METHODS

We collected subglottic tissue biopsies from 12 patients during direct laryngoscopy, immediately prior to surgical treatment of iSGS; as well as from 4 age-, sex-, and race/ethnicity-matched control patients undergoing other direct laryngoscopic procedures. We isolated protein and genomic DNA, acquired proteomic data using label-free quantitative mass spectrometry techniques, and acquired genome-wide methylation data using bisulfite conversion and a microarray platform. We compared molecular profiles across the iSGS and control groups, and with respect to clinical course in the iSGS group. Eight of the 12 iSGS patients underwent subsequent blood collection and plasma isolation for further assessment.

RESULTS

Proteomic analysis revealed 42 differentially abundant proteins in the iSGS biopsies compared to controls, inferring enrichment of biological pathways associated with early wound healing, innate immunity, matrix remodeling, and metabolism. Proteome-based hierarchical clustering organized patients into two iSGS and one control subgroups. Methylation analysis revealed five hypermethylated genes in the iSGS biopsies compared to controls, including the biotin recycling enzyme biotinidase (BTD). Follow-up analysis showed elevated plasma BTD activity in iSGS patients compared to both controls and published normative data.

CONCLUSION

iSGS exhibits distinct proteomic and genomic methylation signatures. These signatures expand current understanding of the iSGS phenotype, support the possibility of disease subgroups, and should inform the direction of future experimental studies.

LEVEL OF EVIDENCE

Not applicable Laryngoscope, 131:E540-E546, 2021.

The role of inflammatory cytokines in the development of idiopathic subglottic stenosis

Idiopathic subglottic stenosis (iSGS) is a debilitating extrathoracic obstruction involving the lower laryngeal and upper tracheal airway. It arises without a known antecedent injury or associated disease process. iSGS is a fibrotic disease marked histologically by excessive accumulation of fibrous connective tissue components of the extracellular matrix (ECM, i.e., collagen and fibronectin) in inflamed tissue, which leads to airway obstruction and clinical dyspnea. Diverse diseases in divergent organ systems are associated with fibrosis, suggesting common pathogenic pathways. One of the most common is sustained host inflammation. Recent investigations focusing on the inflammatory response associated with iSGS have sought to characterize the immunophenotype and cytokine profile of the airway scar in iSGS. While the role of the immune response as inciting event in iSGS remains unresolved, the centrality of an active immune response to the observed subglottic tissue remodeling is becoming more defined.

Office-Based Steroid Injections for Idiopathic Subglottic Stenosis: Patient-Reported Outcomes, Effect on Stenosis, and Side Effects

Objective:

Office-based steroid injection has shown promise for idiopathic subglottic stenosis (iSGS). It is important to understand safety and patient-lived experience. We report patient experience related to airway restriction, voice, and side effects.

Methods:

Sixteen patients (51 ± 14 years) with mild-moderate (20-50%) stenosis undergoing office-based transnasal steroid injections were included; fourteen had prior operations. Patients typically underwent three injections, 1 month apart, followed by transnasal tracheoscopy 1 month later to evaluate outcome; number of injections can vary based on disease severity and response. Outcomes were Dyspnea Index (DI), Modified Medical Research Council (MMRC) dyspnea scale, voice handicap index-10 (VHI-10), and degree of stenosis (estimated from procedural video). At each visit, patients were queried about post-injection airway restriction and side effects. Paired t-tests compared values at baseline versus follow-up tracheoscopy.

Results:

DI decreased ( t = 3.938, P = 0.0013), as did MMRC ( t = 2.179, P = 0.0457). There was no change in VHI-10 ( t = 1.354; P = 0.1957) scores. Airway stenosis decreased ( t = 4.331; P = 0.0006); this was not correlated with change in DI ( r = 0.267, P = 0.318). Side effects included airway restriction lasting <48 hours (n = 5), cough (n = 3), and nasal pain (n = 2).

Conclusion:

Steroid injections improved upper airway symptoms. Side effects were mild and transient. Improvement in DI did not correlate with percent stenosis.

The minimal clinically important difference of the dyspnea index in laryngotracheal stenosis

OBJECTIVE

The Dyspnea Index (DI) is a validated patient-reported outcome (PRO) instrument that has been used in the management of laryngotracheal stenosis (LTS). The minimal clinically important difference (MCID) is an established concept to help determine the change in a PRO instrument that reflects meaningful change for the patient. It is not known what change in the DI is of clinical significance in airway surgery. This study aims to determine the MCID for the DI in patients undergoing surgical treatment for LTS.

METHODS

This is a prospective cohort study in which 26 patients with LTS completed the DI (score range 0 to 40) before and 6 to 8 weeks postoperatively, in addition to a Global Ratings Change Questionnaire (GRCQ), scored from -7 to +7, at the postoperative interval. A hypothesis test was carried out to test the association between GRCQ and change in DI. The MCID for change in DI was determined using anchor-based analysis.

RESULTS

Overall mean change in DI was -11, and mean change in GRCQ was +5. Change in DI scores were significantly different among the improvement and no improvement groups (P value <0.002). Area under the receiver operating curve was 0.92, demonstrating high discriminatory ability of the change in DI score. A change of -4 was determined to be the threshold that discriminated between significant improvement and no improvement.

CONCLUSION

A decrease of 4 in the DI can be considered as the MCID for patients with LTS after surgical treatment.

LEVEL OF EVIDENCE

2b Laryngoscope, 130:1775-1779, 2020.

Vocal fold fixation due to proximal stenosis progression complicating idiopathic subglottic stenosis

Purpose

This study examined the incidence and risk factors for vocal fold fixation due to proximal progression of idiopathic subglottic stenosis (ISS) over the course of serial treatments.

Methods

Records of 22 consecutive patients with ISS treated between 2004 and 2016 were retrospectively reviewed. Patient, stenosis, and treatment details were recorded. Cox regression was used to identify independent predictors of vocal fold fixation.

Results

All patients were female and mean age at diagnosis was 46 ± 7 years. In five patients, the stenosis was within 15 mm of the glottis at first treatment. Vocal fold fixation due to proximal stenosis progression occurred in seven (32%) patients. It led to permanent hoarseness due to unilateral vocal fold fixation in two patients and caused airway compromise due to bilateral vocal fixation in two other patients. No airway-related deaths occurred and no patient required a tracheostomy. Stenosis incision using coblation or potassium titanyl phosphate laser, and an initial glottis-to-stenosis (GtS) distance < 15 mm significantly increased the risk of proximal stenosis progression on univariable analysis.

Conclusion

Vocal fold fixation due to proximal stenosis progression is a significant complication of idiopathic subglottic stenosis and causes permanent voice and/or airway sequelae. It should be actively looked for and documented every time a patient is assessed. If a reduction in the GtS distance is observed, definitive surgery should be promptly considered before proximal stenosis progression compromises the efficacy and safety of definitive treatment or, worse, causes vocal fold fixation.

Office-based corticosteroid injections as adjuvant therapy for subglottic stenosis

Objective

Subglottic stenosis (SGS) is a serious, potentially life‐threatening disorder that is difficult to treat due to significant recurrence rates. While conventional treatment of SGS relies heavily on serial endoscopic dilation procedures, this study aims to characterize the efficacy of incorporating subglottic corticosteroid injections in increasing surgery‐free intervals (SFIs) for a cohort of patients at a university‐based medical system.

Study Design

Retrospective chart review.

Methods

All SGS patients who underwent endoscopic dilation and at least one adjuvant office‐based serial intralesional steroid injection (SILSI) were reviewed. Patients were excluded if they had synchronous airway lesions or stenosis outside of the subglottis. Charts were reviewed for demographic and treatment‐specific data. The SFI was calculated for patients both prior to the initiation of SILSI and after. Groups were compared via Mann–Whitney U test, with P < .05 as the threshold for significance.

Results

Thirteen patients met criteria, with mean age 50.1 ± 14.1 years and 7:6 female to male ratio. Eight of the thirteen (61.5%) had intubation‐related stenosis, while 4/13 were idiopathic and 1/13 was due to Wegener's granulomatosis. Mean follow‐up was 20.4 months. Patients underwent an average of 4.2 ± 2.2 postoperative injections, beginning 45.9 ± 19.0 days after surgery. The mean SFI prior to initiating SILSI was 288.6 ± 362.0 days; while after receiving SILSI, the mean interval was significantly longer (545.5 ± 152.7 days, P = .0041).

Conclusions

We demonstrate that office‐based corticosteroid injection for SGS was associated with a statistically significant improvement in the SFI and is a promising adjuvant approach. Future prospective studies should evaluate if the efficacy is reproducible on a large scale and if SILSI can and/or should be incorporated into the standard management paradigm for SGS treatment.

Level of Evidence

4

Assessment and Treatment of Pain during In-Office Otolaryngology Procedures: A Systematic Review

OBJECTIVE

To qualitatively assess practices of periprocedural pain assessment and control and to evaluate the effectiveness of interventions for pain during in-office procedures reported in the otolaryngology literature through a systematic review.

DATA SOURCES

PubMed, CINAHL, and Web of Science searches from inception to 2018.

REVIEW METHODS

English-language studies reporting qualitative or quantitative data for periprocedural pain assessment in adult patients undergoing in-office otolaryngology procedures were included. Risk of bias was assessed via the Cochrane Risk of Bias or Cochrane Risk of Bias in Non-Randomized Studies of Interventions tools as appropriate. Two reviewers screened all articles. Bias was assessed by 3 reviewers.

RESULTS

Eighty-six studies describing 32 types of procedures met inclusion criteria. Study quality and risk of bias ranged from good to serious but did not affect assessed outcomes. Validated methods of pain assessment were used by only 45% of studies. The most commonly used pain assessment was patient tolerance, or ability to simply complete a procedure. Only 5.8% of studies elicited patients' baseline pain levels prior to procedures, and a qualitative assessment of pain was done in merely 3.5%. Eleven unique pain control regimens were described in the literature, with 8% of studies failing to report method of pain control.

CONCLUSION

Many reports of measures and management of pain for in-office procedures exist but few employ validated measures, few are standardized, and current data do not support any specific pain control measures over others. Significant opportunity remains to investigate methods for improving patient pain and tolerance of in-office procedures.

T-Helper 2 Lymphocyte Immunophenotype Is Associated With Iatrogenic Laryngotracheal Stenosis

OBJECTIVE/HYPOTHESIS

This prospective controlled human and murine study assessed the presence of inflammatory cells and cytokines to test the hypothesis that immune cells are associated with fibroproliferation in iatrogenic laryngotracheal stenosis (iLTS).

METHODS

Inflammation was assessed by histology and immunofluorescence (IF), quantitative real-time polymerase chain reaction (qRT-PCR), and flow cytometry of cricotracheal resections of iLTS patients compared to normal controls. An iLTS murine model assessed the temporal relationship between inflammation and fibrosis.

RESULTS

iLTS specimens showed increased inflammation versus normal controls (159/high power field [hpf] vs. 119/hpf, P = 0.038), and increased CD3 + T-cells, CD4 + cells, and CD3+/CD4 + T-helper (T_H ) cells (all P < 0.05). The inflammatory infiltrate was located immediately adjacent to the epithelial surface in the superficial aspect of the thickened lamina propria. Human flow cytometry and qRT-PCR showed a significant increase in interleukin (IL)-4 gene expression, indicating a T_H 2 phenotype. Murine IF revealed a dense CD4 + T-cell inflammatory infiltrate on day 4 to 7 postinjury, which preceded the development of fibrosis. Murine flow cytometry and qRT-PCR studies mirrored the human ones, with increased T-helper cells and IL-4 in iLTS versus normal controls.

CONCLUSION

CD3/CD4 + T-helper lymphocytes and the proinflammatory cytokine IL-4 are associated with iLTS. The association of a T_H 2 immunophenotype with iLTS is consistent with findings in other fibroinflammatory disorders. The murine results reveal that the inflammatory infiltrate precedes the development of fibrosis. However, human iLTS specimens with well-developed fibrosis also contain a marked chronic inflammatory infiltrate, suggesting that the continued release of IL-4 by T-helper lymphocytes may continue to propagate iLTS.

LEVEL OF EVIDENCE

NA Laryngoscope, 129:177-186, 2019.

Pathologic Fibroblasts in Idiopathic Subglottic Stenosis Amplify Local Inflammatory Signals

OBJECTIVE

To characterize the phenotype and function of fibroblasts derived from airway scar in idiopathic subglottic stenosis (iSGS) and to explore scar fibroblast response to interleukin 17A (IL-17A).

STUDY DESIGN

Basic science.

SETTING

Laboratory.

SUBJECTS AND METHODS

Primary fibroblast cell lines from iSGS subjects, idiopathic pulmonary fibrosis subjects, and normal control airways were utilized for analysis. Protein, molecular, and flow cytometric techniques were applied in vitro to assess the phenotype and functional response of disease fibroblasts to IL-17A.

RESULTS

Mechanistically, IL-17A drives iSGS scar fibroblast proliferation ( P < .01), synergizes with transforming growth factor ß1 to promote extracellular matrix production (collagen and fibronectin; P = .04), and directly stimulates scar fibroblasts to produce chemokines (chemokine ligand 2) and cytokines (IL-6 and granulocyte-macrophage colony-stimulating factor) critical to the recruitment and differentiation of myeloid cells ( P < .01). Glucocorticoids abrogated IL-17A-dependent iSGS scar fibroblast production of granulocyte-macrophage colony-stimulating factor ( P = .02).

CONCLUSION

IL-17A directly drives iSGS scar fibroblast proliferation, synergizes with transforming growth factor ß1 to promote extracellular matrix production, and amplifies local inflammatory signaling. Glucocorticoids appear to partially abrogate fibroblast-dependent inflammatory signaling. These results offer mechanistic support for future translational study of clinical reagents for manipulation of the IL-17A pathway in iSGS patients.

Serial intralesional triamcinolone acetonide injections for acquired subglottic stenosis in premature infants

PURPOSE

Long-term intubation of premature infants sometimes induces acquired subglottic stenosis (SGS), causing glottic or supraglottic problems. These kinds of SGS often require tracheostomy and subsequently make decannulation difficult. The aim of our study was to clarify the efficacy of repeated intralesional steroid injections to the stenosis.

METHODS

Six children with acquired SGS, who were treated with triamcinolone acetonide injections to the subglottic space just below the vocal folds between September 2015 and December 2017 were retrospectively reviewed.

RESULTS

The patients' mean age was 4.3 (range 1.3-4.4) years, the mean gestational age at birth was 25 (23-28) weeks, and the mean birth weight was 591 (456-734) g. The degree of SGS was grade II in one patient and III in five patients, with both tracheostoma and glottic or supraglottic abnormalities. They generally underwent ten procedures, every 3-4 weeks. In most cases, the patency of the injected space improved by 25-220%, and the symptoms were relieved. One patient achieved decannulation, and another one underwent laryngotracheal reconstruction and decannulation. Two patients started using a speech cannula. There were no severe complications.

CONCLUSION

Serial intralesional steroid injections are likely to be effective in improving the patency of acquired SGS.