Use of Steroid Injections to Prevent the Recurrence of Tracheal Stenosis in Idiopathic Subglottic Stenosis

Inclusion Criteria: * Have a life expectancy of ≥6 months; and, * Eastern Cooperative Oncology Group (ECOG) performance status of 0 - 1. Exclusion Criteria: * History of subglottic stenosis from identifiable cause (not idiopathic), including any of the below clinical criteria: * Prolonged endotracheal intubation or tracheostomy (intervention greater than 7 days immediately prior to diagnosis of subglottic stenosis); * External physical trauma (including but not limited to blunt, penetration, chemical, or thermal injury) that causes injury to the subglottis; * Clinical diagnosis of granulomatosis with polyangiitis (GPA); * Radiation exposure to the neck; * Current or previous treatment with Serial Intralesional Steroid Injection (SILSI); * Use of systemic corticosteroids (oral, intravenous, or intramuscular glucocorticoids), regardless of indication, within 7 days before triamcinolone administration; * Local administration of corticosteroids (ophthalmic, intranasal, inhaled) is not prohibited. However, the administration of intraarticular corticosteroids during the treatment phase is not recommended due to potential increased risk of infection. * Intralesional administration, in a site other than the subglottis, of corticosteroids should be discussed with the site PI before enrollment * Intraarticular corticosteroids during the treatment phase due to potential increased risk of infection; * Use of anticoagulants other than aspirin (aspirin dose should not exceed 81mg); * Pulmonary disease including interstitial lung disease and Chronic Obstructive Pulmonary Disease (COPD)/emphysema; * Systemic infection requiring treatment with antibiotics, antifungal, or antiviral agents within 21 days of enrollment; * Poorly controlled diabetes as defined by a HbA1C value greater or equal to 8.0 in the last 180 days); * Participants with active cancer or a history of cancer in the last 5 years, except for squamous or basal cell carcinoma of the skin; * Participation in any clinical trial involving an investigational drug or device, within four weeks, or 5 half-lives of the investigational agent (whichever time point is longer) prior to enrollment or during this trial participation; * Active autoimmune disease requiring systemic treatment; * History of solid organ transplant due to use of immunosuppression; * Contraindication to any aspect of the index endoscopic dilation procedure. * Inability to tolerate in office SILSI procedure; * Contraindication, hypersensitivity, or history of intolerance to oral or injectable steroids; * Contraindication to intralipid including: * Severe lipid metabolism disorders characterized by hypertriglyceridemia; * Hypersensitivity to eggs, soybean, peanut protein, or any active ingredient in intralipid; * History of intolerance to intralipid; * Participants with known, suspected, or plan for becoming pregnant or breastfeeding; * New York Heart Association (NYHA) class II-IV heart failure within the past 6 months; * History of angioedema; * History of subglottic stenosis from other causes, including prolonged intubation (intubation of \>1 week immediately prior to diagnosis of subglottic stenosis, external physical trauma that causes injury to the subglottis); * Lack of capacity to consent; * Alcohol or substance abuse or dependence in the past 6 months; * Participants who for any reason may not complete the study as judged by the PI; * Participants planning to move to another city or state during the duration of the study; * Not able to undergo phlebotomy as reported by the participant or determined by the study coordinator or physician. * The presence of a medical condition, and/or use of a medication and/or any substance, individually or in aggregate, that in the judgement of the study team could impair study participation.