Current concepts in severe adult tracheobronchomalacia: evaluation and treatment

Tracheobronchomalacia vs Excessive Dynamic Airway Collapse

Tracheobronchomalacia (TBM) is a frequently under-recognized condition that often coexists with other chronic respiratory diseases. The diagnosis of excessive central airway collapse requires consideration by the physician. Dynamic computed tomography scan of the chest and awake dynamic bronchoscopy are critical to establishing a diagnosis of TBM. Patients with severe TBM are candidates for tracheobronchoplasty. Multidisciplinary evaluation of patients with TBM has the potential benefit derived from shared decision-making to ensure patient optimization, prehabilitation, periprocedural care and posttreatment recovery, rehabilitation, and follow-up. Robotic tracheobronchoplasty is safe and improves pulmonary function tests and quality of life in patients with severe TBM.

Unexplained disabling and long-lasting cough: a case report

BACKGROUND

A 51-year-old woman was referred to our department due to chronic dry cough lasting six years without an etiological diagnosis. The patient suffered from chronic deterioration in her quality of life due to a persistent cough that sounded like a barking seal.

CASE PRESENTATION

A severe form of malacia involving the inferior third of trachea and the main bronchi was diagnosed. According to our protocol, a self-expandable prothesis was placed in the distal portion of the trachea via rigid bronchoscopy with excellent results in cough relief. The patient was subsequently scheduled for tracheobronchoplastic surgery with a polypropylene matrix. Two and a half years after surgery the patient had a significant improvement in quality of life with a complete resolution of her symptoms.

CONCLUSION

This report demonstrated that tracheobronchomalacia can be difficult to diagnose with a serious impact on the patient's life. Referral to a specialized center is essential in the diagnostic and therapeutic management of this disease. Surgical treatment by tracheobronchoplasty may represent a good solution in selected patients.

Predicting life-threatening hemoptysis in traumatic pulmonary parenchymal injury using computed tomography semi-automated lung volume quantification

OBJECTIVES

Chest computed tomography (CT) can diagnose and assess the severity of pulmonary contusions. However, in cases of severe lung contusion, the total lung volume ratio may not accurately predict severity. This study investigated the association between life-threatening hemoptysis and chest CT imaging data on arrival at the emergency department in patients with pulmonary contusions or lacerations due to blunt chest injury.

METHODS

The records of 277 patients with lung contusions or lacerations treated at a trauma center between 2018 and 2022 were retrospectively reviewed. The ratio of the local lung contusion volume to lobe volume in each lobe was calculated from chest CT images. The maximal ratio in the Hounsfield unit (HU) range was defined as the highest ratio value within the HU range among five lobes.

RESULTS

The median patient age was 41 years, and 68.6% were male. Life-threatening hemoptysis occurred in 39 patients. The area under the receiver operating characteristic curve for the maximal ratio at -500 HU to 100 HU was 96.52%. The cutoff value was 45.49%. Multivariate analysis showed a high maximal chest CT ratio ≥ 45.49% at -500 HU to 100 HU (adjusted odds ratio [aOR]: 104.66, 95% confidence interval [CI]: 21.81-502.16, p < 0.001), hemopneumothorax (aOR: 5.18, 95% CI: 1.25-21.47, p = 0.023), and chest abbreviated injury scale (AIS, aOR: 5.58, 95% CI: 1.68-18.57, p = 0.005) were associated with life-threatening hemoptysis.

CONCLUSIONS

Maximal chest CT ratios ≥ 45.49% at -500 HU to 100 HU, hemopneumothorax, and high chest AIS scores are associated with life-threatening hemoptysis in patients with blunt chest trauma.

CRITICAL RELEVANCE STATEMENT

The present study provides an objective index derived from chest CT images to predict the occurrence of life-threatening hemoptysis. This information helps screen high-risk patients in need of more intensive monitoring for early intervention to improve outcomes.

KEY POINTS

Emergency department CT helps predict life-threatening hemoptysis in patients with lung contusions. Maximal CT ratios ≥ 45.49% (-500 HU to 100 HU, either lung lobe) are associated with life-threatening hemoptysis. High chest abbreviated injury scale scores and hemopneumothorax also predict life-threatening hemoptysis.

Airway Stents for Excessive Central Airway Collapse: A Randomized Controlled Open-label Trial

BACKGROUND

Short-term airway stent placement (stent evaluation) has been employed to evaluate whether patients with excessive central airway collapse (ECAC) will benefit from tracheobronchoplasty. Although retrospective studies have explored the impact of stent placement on ECAC, prospective randomized controlled trials are absent.

METHODS

This was a randomized open-label trial comparing patients receiving airway stent placement and standard medical treatment (intervention group) versus standard medical treatment alone (control group) for ECAC. At baseline, patients' respiratory symptoms, self-reported measures, and functional capabilities were assessed. Follow-up evaluations occurred 7 to 14 days postintervention, with an option for the control group to crossover to stent placement. Follow-up evaluations were repeated in the crossover patients.

RESULTS

The study enrolled 17 patients in the control group [medical management (MM)] and 14 patients in the intervention group. At follow-up, 15 patients in the MM crossed over to the stent group, resulting in a total of 29 patients in the combined stent group (CSG). Subjectively (shortness of breath and cough), 45% of the CSG exhibited improvement with the intervention compared with just 12% in the MM. The modified St. George Respiratory Questionnaire score in the CSG improved significantly from 61.2 at baseline to 52.5 after stent placement (-8.7, P = 0.04). With intervention, the 6-minute walk test in CSG improved significantly from 364 meters to 398 meters (34 m, P < 0.01). The MM did not show a significant change in the St. George Respiratory Questionnaire score or 6-minute walk test distance.

CONCLUSION

Short-term airway stent placement in patients with ECAC significantly improves respiratory symptoms, quality of life, and exercise capacity.

Ultralow-Dose Dynamic Expiratory CT and Repeated Imaging Enhance Evaluation for Tracheomalacia

OBJECTIVE

This study aims to determine if a novel imaging protocol (ultralow-dose dynamic expiratory computed tomography [CT] with repeated imaging) identifies tracheomalacia (TM) more reliably than traditional dynamic tracheal CT.

METHODS

We performed a retrospective evaluation of 184 consecutive ultralow-dose dynamic CTs for TM during 2017. The protocol obtains images during 1 inspiration and 2 forced expirations. Tracheal narrowing during both expirations (airway narrowing [percentage] during first dynamic expiration CT [DE1], airway narrowing [percentage] during second dynamic expiration CT [DE2]) was reported as a percentage of inspiratory area. We identified maximum narrowing of each patient's sequence (maximum narrowing [percentage] on either dynamic expiration CT [DEmax] = greatest narrowing of DE1 or DE2) and compared DE1, DE2, and DEmax in individual studies and between patients. Outcomes included frequency of TM, tracheal narrowing, and severity. Reliability was assessed by comparing tracheal area narrowing and TM grade.

RESULTS

There was significantly more airway narrowing using 2 expiratory image acquisitions. Average DEmax tracheal area was 12% narrower than DE1 alone and 21% worse than DE2 alone (both P < 0.001). Using DEmax, TM was diagnosed 35% more often than DE1 alone and 31% more often than DE2 alone ( P < 0.001). DEmax identified more severe distribution of TM compared with DE1 or DE2 alone ( P < 0.001). Reliability between DE1 and DE2 was good for tracheal narrowing and moderate for TM grade. The mean effective radiation dose was 2.41 millisievert (mSv) for routine inspiration CT and 0.07 mSv for each dynamic expiration CT (total effective radiation, 2.55 mSv).

CONCLUSIONS

Dynamic expiration CT with 2 expiratory image acquisitions enhanced evaluation of TM, minimally increased radiation dose, and should be considered as a noninvasive screening option.

Adult Tracheobronchomalacia that Progressed Following Radiotherapy in an Advanced-stage Lung Cancer Patient: A Rare Case Report

Tracheobronchomalacia (TBM) is the collapse of the trachea and bronchi, which leads to respiratory symptoms and complications, often on forced expiration. Radiotherapy (RT) is a rare cause of adult TBM. Here, we report the first case of progressive TBM following palliative RT in a patient with squamous cell lung carcinoma. TBM was diagnosed by fiberoptic bronchoscopy and thoracic CT scans. In patients with advanced-stage lung cancer who experience worsening dyspnea and cough following palliative RT, TBM should also be taken into account.

Unexpected Airway Collapse: A Rare Case of Spontaneous Postoperative Tracheobronchomalacia in the Absence of Identifiable Risk Factors

We report the case of a 53-year-old female who developed tracheobronchomalacia immediately following an uncomplicated robotic hysterectomy with bilateral salpingo-oophorectomy to treat postmenopausal bleeding. Induction of anesthesia was notable for moderately difficult intubation, managed with applied cricothyroid pressure and a small 6.5 endotracheal tube placement via GlideScope. The surgical course was uneventful. The patient remained intubated in the post-anesthesia care unit but was not providing end-tidal volumes. Attempts to replace the endotracheal tube with a larger tube were unsuccessful and the patient was temporarily unable to ventilate. Rapid troubleshooting discovered that a laryngeal mask airway (LMA) could sufficiently ventilate the patient. An otolaryngologist was able to perform direct bronchoscopy, which revealed more than 50% dynamic anterior-posterior collapse of the trachea and bronchi. The patient was subsequently awakened from anesthesia and monitored in the intensive care unit, ventilating with an LMA. After a couple of hours, it was determined that the patient's airway was protected, and the LMA was removed.

Assessment of MMP-9 and clinical characteristics in dogs with tracheal collapse based on cough severity and fluoroscopic findings: a cross-sectional study

BACKGROUND

Tracheal collapse (TC), a common disease in dogs, is characterized by cough; however, little is known about the serum biomarkers that can objectively evaluate the severity of cough in canine TC. Furthermore, studies elucidating the relationship of fluoroscopic characteristics with the severity of cough are lacking. Therefore, this study aimed to evaluate the relationship between cough severity and clinical characteristics, fluoroscopic images, and new serum biomarkers in canine TC.

RESULTS

Fifty-one client-owned dogs diagnosed with TC based on fluoroscopic and clinical signs were enrolled in this study and divided into three groups according to the severity of cough (grade of cough: 0, 1, and 2). Signalments, comorbidities, and fluoroscopic characteristics were compared among the groups retrospectively. The serum matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6), surfactant protein-A (SP-A), and syndecan-1 (SDC-1) levels were measured in all groups. No significant differences in age, breed, sex, or clinical history were observed among the groups. Concomitant pharyngeal collapse increased significantly with the severity of cough (p = .031). Based on the fluoroscopic characteristics, the TC grade of the carinal region increased significantly and consistently with the grade of cough (p = .03). The serum MMP-9 level was significantly higher in the grade 2 group than that in the grade 0 group (p = .014). The serum IL-6 level was significantly lower in the grade 1 group than that in the grade 0 group (p = .020). The serum SP-A and SDC-1 levels did not differ significantly among the groups.

CONCLUSIONS

The severity of cough with the progression of TC can be predicted with the fluoroscopic TC grade at the carinal region. MMP-9 may be used as an objective serum biomarker that represents cough severity to understand the pathogenesis.

Incidence of Airway Complications in ICU

To show the incidence of airway complications in ICU. Endotracheal intubation is an essential skill performed by multiple medical specialists to secure a patient's airway as well as provide oxygenation and ventilation through the oral route or nose. The goal of endotracheal intubation in the emergency setting is to secure the patient's airway and obtain first-pass success. There are many indications for endotracheal intubation, including poor respiratory drive, questionable airway patency, hypoxia, and Hypercapnia. These indications are assessed by evaluating the patient's mental status, conditions that may compromise the airway, level of consciousness, respiratory rate, respiratory acidosis, and level of oxygenation. In the setting of trauma, a Glasgow Coma Scale of 8 or less is generally an indication for intubation. There are many different complications of intubation as hoarseness of voice, dental injuries, arytenoid dislocation, laryngeal stenosis, tracheal stenosis and tracheomalacia. . 150 patients who were sat in the ICU that developed certain complications. 86 patients (57.3%) were sitting in the ICU develoed certain complications. Liver diseases were the main cause of ICU admission 34 (22.7%) patients then shock 32 (21.3%) patients. Blockage of endotracheal tube was the main ICU complications 18 (12%) patients then sinusitis 16 (10.7%) patients. Endotracheal intubation is a lifesaving procedure and its complications are significant problems in ICUs. A successful procedure of intubation avoids complications. Skilled endotracheal intubation in the ICU decreases the complications.

Tracheobronchomalacia: an unusual cause of debilitating dyspnoea and its surgical management

Tracheobronchomalacia (TBM) is a progressive weakening of the airways, leading to collapse and dyspnoea. TBM can be misdiagnosed when multiple chronic conditions accompany it. Tracheobronchoplasty (TBP) is indicated for severe symptomatic TBM, diagnosed by bronchoscopy and CT thorax. We report the case of a patient who underwent tracheal resection and reconstruction for continuing dyspnoea post argon therapy, TBP and a failure to tolerate extracorporeal membrane oxygenation-assisted Y-stent insertion. Relevant background history includes asthma, sleep apnoea, reflux, cardiomyopathy and a high body mass index. Bronchoscopy postreconstruction showed patent airways. Airway reconstruction was a viable management option for this patient's TBM. TBP is a treatment option for TBM. In this case, tracheal resection was required to sustain benefit. In addition, surveillance bronchoscopies will be carried out every year.

[Interventionnal bronchoscopy for the treatment of tracheobronchomalacia]

Tracheobronchomalacia is usually characterized by more than 50% expiratory narrowing in diameter of the trachea and the bronchi. The expiratory collapse includes two entities: (1) the TBM related to the weakness of the cartilaginous rings, and (2) the Excessive Dynamic Airway Collapse (EDAC) due to the excessive bulging of the posterior membrane. Patients have nonspecific respiratory symptoms like dyspnea and cough. Diagnosis is confirmed by dynamic tests: flexible bronchoscopy and/or computed tomographic scan of the chest. There are different forms of tracheobronchomalacia in adults: primary (genetic, idiopathic) or secondary to trauma, tracheotomy, intubation, surgery, transplantation, emphysema, infection, inflammation, chronic bronchitis, extrinsic compression; or undiagnosed in childhood vascular rings. Some management algorithms have been proposed, but no specific recommendation was established. Only symptomatic patients should be treated. Medical treatments and noninvasive positive pressure ventilation should be the first line therapy, after evaluation of various quality measures (functional status, performance status, dyspnea and quality of life scores). If symptoms persist, therapeutic bronchoscopy permits: (1) patient's selection by stent trial to determine whether patient benefit for surgical airway stabilization; (2) malacic airways stenting in patients who are not surgical candidates, improving QOL despite a high complication rate; (3) the management of stent-related complication (obstruction, plugging, migration granuloma); (4) alternative therapeutics like thermo-ablative solution. Lasty, the development of new types of stents would reduce the complication rates. These different options remained discussed.

Thermoablative Techniques to Treat Excessive Central Airway Collapse

Excessive central airway collapse (ECAC) is a condition characterized by the excessive narrowing of the trachea and mainstem bronchi during expiration, which can be caused by Tracheobronchomalacia (TBM) or Excessive Dynamic Airway Collapse (EDAC). The initial standard of care for central airway collapse is to address any underlying conditions such as asthma, COPD, and gastro-esophageal reflux. In severe cases, when medical treatment fails, a stent-trial is offered to determine if surgical correction is a viable option, and tracheobronchoplasty is suggested as a definitive treatment approach. Thermoablative bronchoscopic treatments, such as Argon plasma coagulation (APC) and laser techniques (potassium-titanyl-phosphate [KTP], holmium and yttrium aluminum pevroskyte [YAP]) are a promising alternative to traditional surgery. However, further research is needed to assess their safety and effectiveness in humans before being widely used.

Excessive Dynamic Airway Collapse Severity Scoring System: A Call Out for an Overall Severity Determination

BACKGROUND

Severe excessive dynamic airway collapse (EDAC) is defined as airway narrowing due to posterior wall protrusion into the airway lumen, >90%. We aimed to establish an overall severity score to assess severe EDAC and the need for subsequent intervention.

METHODS

A retrospective study of patients who underwent dynamic bronchoscopy for evaluation of expiratory central airway collapse between January 2019 and July 2021. A numerical value was given to each tracheobronchial segmental collapse: 0 points (<70%), 1 point (70% to 79%), 2 points (80% to 89%), and 3 points (>90%) to be added for an overall EDAC severity score per patient. We compared the score among patients who underwent stent trials (severe EDAC) and those who did not. Based on the receiver operating characteristics curve, a cutoff total score to predict severe EDAC was calculated.

RESULTS

One hundred fifty-eight patients were included. Patients were divided into severe (n = 60) and nonsevere (n = 98) EDAC. A cutoff of 9 as the total score had a sensitivity of 94% and a specificity of 74% to predict severe EDAC, based on an area under the curve 0.888 (95% CI: 0.84, 0.93; P < 0.001).

CONCLUSION

Our EDAC Severity Scoring System was able to discern between severe and nonsevere EDAC by an overall score cutoff of 9, with high sensitivity and specificity for predicting severe disease and the need for further intervention, in our institution.

Tracheobronchoplasty: Indications and Best Approaches

Tracheobronchomalacia (TBM) is an increasingly recognized abnormality of the central airways in patients with respiratory symptoms. Severe TBM in symptomatic patients warrants screening dynamic CT of the chest and/or awake dynamic bronchoscopy. The goal of surgical repair is to restore the C-shaped configuration of the airway lumen and splint or secure the lax posterior membrane to the mesh to ameliorate symptoms. Robotic tracheobronchoplasty is safe and associated with improvements in pulmonary function and subjective improvement in quality of life.

Pre-treatment bronchoscopic evaluation in a case of relapsing polychondrits

BACKGROUND

Relapsing polychondritis (RP) is a chronic and recurrent inflammatory disease of the cartilage tissues in the body. The cause of RP is unknown, and since it is a rare disease with symptoms that affect multiple organs, diagnosis is often delayed.

CASE PRESENTATION

A 62-year-old woman with no smoking history visited our institution complaining of fever, cough, and dyspnoea. Chest CT showed a stenosis from the left main bronchus to the left lower lobe branch. Bronchoscopy visualised intense erythema and oedema at the left main bronchus, with airway narrowing. Biopsy of the ear revealed degenerative vitreous cartilage and fibrous connective tissue with a mild inflammatory cell infiltrate. She was subsequently diagnosed with RP and administered systemic corticosteroid therapy. Her symptoms improved rapidly, and post-treatment bronchoscopy revealed that although mild erythema of the airway epithelium remained, oedema markedly improved, and the airway stenosis was resolved.

CONCLUSIONS

We report a case where pre-treatment bronchoscopy was able to visually confirm RP at the acute stage. Since RP is difficult to diagnose, severe airway narrowing can occur prior to diagnosis. Therefore, to determine the stage of the disease, it is helpful to perform bronchoscopic observation before treatment. However, bronchoscopic observation before treatment should be performed by experienced bronchoscopists due to the risk of airway obstruction.

Computer-based airway stenosis quantification from bronchoscopic images: preliminary results from a feasibility trial

PURPOSE

Airway Stenosis (AS) is a condition of airway narrowing in the expiration phase. Bronchoscopy is a minimally invasive pulmonary procedure used to diagnose and/or treat AS. The AS quantification in a form of the Stenosis Index (SI), whether subjective or digital, is necessary for the physician to decide on the most appropriate form of treatment. The literature reports that the subjective SI estimation is inaccurate. In this paper, we propose an approach to quantify the SI defining the level of airway narrowing, using depth estimation from a bronchoscopic image.

METHODS

In this approach we combined a generative depth estimation technique combined with depth thresholding to provide Computer-based AS quantification. We performed an interim clinical analysis by comparing AS quantification performance of three expert bronchoscopists against the proposed Computer-based method on seven patient datasets.

RESULTS

The Mean Absolute Error of the subjective Human-based and the proposed Computer-based SI estimation was [Formula: see text] [%] and [Formula: see text] [%], respectively. The correlation coefficients between the CT measurements were used as the gold standard, and the Human-based and Computer-based SI estimation were [Formula: see text] and 0.46, respectively.

CONCLUSIONS

We presented a new computer method to quantify the severity of AS in bronchoscopy using depth estimation and compared the performance of the method against a human-based approach. The obtained results suggest that the proposed Computer-based AS quantification is a feasible tool that has the potential to provide significant assistance to physicians in bronchoscopy.

Nocturnal continuous positive airway pressure offers symptomatic benefit in excessive dynamic airway collapse despite normal sleep study

Excessive dynamic airway collapse (EDAC) and tracheobronchomalacia (TBM) cause debilitating symptoms yet are often misdiagnosed as asthma or chronic obstructive pulmonary disease (COPD). EDAC/TBM should be considered in all cases of obstructive ventilatory defect refractory to medical management. Diagnosis is made with flexible bronchoscopy and/or inspiratory and expiratory phase computed tomography (CT) scans. Treatment should be individualised and "pneumatic stenting" with the use of continuous positive airway pressure (CPAP) may lead to symptomatic relief, and in some cases regardless of the degree of collapse or absence of sleep disordered breathing in overnight oximetry. The case of a 63-year-old female referred to a tertiary respiratory department for a trial of CPAP due to EDAC is presented. Over the course of a few months, she had presented frequently to hospital with cough and shortness of breath which had been attributed to asthma. As she had not responded to treatment, an inpatient flexible bronchoscopy was performed which identified EDAC of the right main bronchus and she was referred to a tertiary ventilation department. Despite a normal sleep study whilst self-ventilating, nocturnal CPAP therapy significantly improved quality and duration of sleep, daytime symptoms and therefore quality of life. She was discharged with nocturnal CPAP and remains adherent to treatment.

Tracheobronchoplasty yields long-term anatomy, function, and quality of life improvement for patients with severe excessive central airway collapse

OBJECTIVES

This study examines the long-term anatomic and clinical effects of tracheobronchoplasty in severe excessive central airway collapse.

METHODS

Included patients underwent tracheobronchoplasty for excessive central airway collapse (2002-2016). The cross-sectional area of main airways on dynamic airway computed tomography was measured before and after tracheobronchoplasty. Expiratory collapse was calculated as the difference between inspiratory and expiratory cross-sectional area divided by inspiratory cross-sectional area ×100. The primary outcome was improvement in the percentage of expiratory collapse in years 1, 2, and 5 post-tracheobronchoplasty. Secondary outcomes included mean response profile for the 6-minute walk test, Cough-Specific Quality of Life Questionnaire, Karnofsky Performance Status score, and St George Respiratory Questionnaire. Repeated-measures analysis of variance was used for statistical analyses.

RESULTS

The cohort included 61 patients with complete radiological follow-up at years 1, 2, and 5 post-tracheobronchoplasty. A significant linear decrease in the percentage of expiratory collapsibility of the central airways after tracheobronchoplasty was present. Anatomic repair durability was preserved 5 years after tracheobronchoplasty, with decrease in percentage of expiratory airway collapse up to 40% and 30% at years 1 and 2, respectively. The St George Respiratory Questionnaire (74.7 vs 41.8%, P < .001) and Cough-Specific Quality of Life Questionnaire (78 vs 47, P < .001) demonstrated significant improvement at year 5 compared with baseline. Similar results were observed in the 6-minute walk test (1079 vs 1268 ft, P < .001) and Karnofsky score (57 vs 82, P < .001).

CONCLUSIONS

Tracheobronchoplasty has durable effects on airway anatomy, functional status, and quality of life in carefully selected patients with severe excessive central airway collapse.

Tracheal Stent Migration in a Patient With Tracheomalacia and Tracheoesophageal Fistula: A Rare Case

Tracheomalacia refers to diffuse or segmental tracheal weakness. Most commonly, tracheomalacia develops after prolonged endotracheal intubation or tracheostomy. Surgical management is warranted in symptomatic patients with severe tracheomalacia. Relief of airway obstruction via stenting often provides immediate improvement in both airflow and symptoms. However, stent placement is associated with significant complications. Here, we present the case of a 71-year-old man who was brought to the emergency department with acute respiratory distress. The patient was known to have tracheomalacia with tracheoesophageal fistula. He had multiple medical comorbidities, including longstanding hypertension, diabetes mellitus, and asthma. The patient had a progressive decline in his level of consciousness and was admitted to the intensive care unit for further management. Despite the maximum ventilatory support, the patient did not achieve an adequate oxygenation level. The patient underwent tracheal stent placement by the interventional radiology team. The insertion was unsuccessful despite three attempts. The tracheal stent had migrated into the upper esophagus on the first and second insertion attempts. Because the patient was unstable to tolerate further attempts, the multidisciplinary team recommended the insertion of an esophageal stent to cover the tracheoesophageal fistula. Despite this, the patient continued to have air leakage with progressive worsening of his respiratory condition as he developed multiorgan failure and died. The management of tracheomalacia in the setting of the tracheoesophageal fistula may pose several challenges. The present case highlights an essential complication of stent placement with the stent migrating into the tracheoesophageal fistula, which is an unusual site of migration. A multidisciplinary approach is crucial in the management of difficult cases of tracheomalacia.

Stent Evaluation for Expiratory Central Airway Collapse: Does the Type of Stent Really Matter?

BACKGROUND

Careful selection of patients with expiratory central airway collapse (ECAC) that may benefit from tracheobronchoplasty (TBP) can be aided by a short-term airway stent evaluation. This can be performed with either silicone Y-stents (SYSs) or uncovered self-expanding metallic airway-stents (USEMAS). No direct comparison has been made between these 2 stent types.

METHODS

This was a small retrospective review of consecutive patients that underwent a stent evaluation. A propensity score was used to match patients in the USEMAS and SYS groups. Outcomes included complications, changes in the health-related quality-of-life (HR-QoL), and changes in exercise capacity. Baseline measurements were compared with those obtained during stent evaluation and after TBP.

RESULTS

Forty-two patients with severe ECAC underwent USEMAS placement, while 18 patients had an SYS placed. Propensity score matching resulted in 13 matched SYS and USEMAS pairs. The SYS group had an increased rate of mucus plugging (38.5% vs. 0%, P <0.047). Although not statically significant, a clinical improvement was observed in HR-QoL and exercise capacity in the USEMAS group during stent placement. In patients who underwent TBP, both USEMAS and SYS groups had a statistically significant change in the Modified Medical Research Council Dyspnea Scale during stent evaluation and after TBP.

CONCLUSION

In patients with severe ECAC, short-term evaluation with airway stents appears to be safe and improves respiratory symptoms, HR-QoL, and exercise capacity. The use of USEMAS led to a lower complication rate, a greater improvement in HR-QoL and exercise capacity, and appeared to better predict how the patients would respond to TBP.

Coordination of Care for Expiratory Central Airway Collapse: A Structured Process for a Multifaceted Disease

Common respiratory symptoms, including dyspnea, cough, sputum production, and recurrent infections, frequently remain without a clear cause and may be the result of expiratory central airway collapse (ECAC). Establishing the diagnosis and appropriate treatment plan for patients with ECAC is challenging and benefits from a multidisciplinary approach. A coordinator role is crucial in this process to ensure optimal patient-centered outcomes. We describe the coordination of care in the process of diagnosing and treating ECAC. The coordinator leads the organization of the multiple services involved in the care of patients with ECAC, including pulmonary medicine, interventional pulmonology, radiology, and thoracic surgery, as well as hospital inpatient staff. From initial screening to evaluation and management with airway stents and corrective treatment with tracheobronchoplasty, the ECAC coordinator oversees the entire process of care for patients with ECAC.

Bronchoscopy Laser and Silicone Y-Stents as Emergency Airway Management in Central Airway Stenosis Due to Secondary Thyroid Carcinoma: A Case Report

Total airway obstruction in thyroid cancer is rare and has high morbidity and mortality. Airway management in such cases is challenging, especially in cases in which thyroid masses cannot be totally resected. It is important to choose the appropriate airway treatment modality. Currently, therapeutic rigid bronchoscopy procedures and endoluminal lasers, as well as airway stent insertion, are a management modality of near-total malignant airway obstruction. We report a rigid bronchoscopy procedure combined with laser and Y-stent silicone insertion in thyroid cancer with extension infiltration, as well as compression in the trachea covering the subglottic tracheal area up to the main carina and tracheo-bronchomalacia, manifesting as acute respiratory failure.

Tracheobronchomalacia and Excessive Dynamic Airway Collapse: Current Concepts and Future Directions

Tracheobronchomalacia (TBM) and excessive dynamic airway collapse (EDAC) are airway abnormalities that share a common feature of expiratory narrowing but are distinct pathophysiologic entities. Both entities are collectively referred to as expiratory central airway collapse (ECAC). The malacia or weakness of cartilage that supports the tracheobronchial tree may occur only in the trachea (ie, tracheomalacia), in both the trachea and bronchi (TBM), or only in the bronchi (bronchomalacia). On the other hand, EDAC refers to excessive anterior bowing of the posterior membrane into the airway lumen with intact cartilage. Clinical diagnosis is often confounded by comorbidities including asthma, chronic obstructive pulmonary disease, obesity, hypoventilation syndrome, and gastroesophageal reflux disease. Additional challenges include the underrecognition of ECAC at imaging; the interchangeable use of the terms TBM and EDAC in the literature, which leads to confusion; and the lack of clear guidelines for diagnosis and treatment. The use of CT is growing for evaluation of the morphology of the airway, tracheobronchial collapsibility, and extrinsic disease processes that can narrow the trachea. MRI is an alternative tool, although it is not as widely available and is not used as frequently for this indication as is CT. Together, these tools not only enable diagnosis, but also provide a road map to clinicians and surgeons for planning treatment. In addition, CT datasets can be used for 3D printing of personalized medical devices such as stents and splints. An invited commentary by Brixey is available online. Online supplemental material is available for this article. ^©RSNA, 2022.

Expiratory central airway collapse during positive pressure ventilation: a case report

Background

Physiologic narrowing of the central airway occurs during expiration. Conditions in which this narrowing becomes excessive are referred to as expiratory central airway collapse. Expiratory central airway collapse is usually managed by applying positive pressure to the airways, which acts as a pneumatic stent. The particularity of the case reported here included the patient’s left main bronchus being permeable during spontaneous breathing but collapsing during general anaesthesia, despite positive pressure ventilation and positive end-expiratory pressure.

Case presentation

We present the case of a 55-year-old man admitted for the placement of a ureteral JJ stent. Rapid desaturation occurred a few minutes after the onset of anaesthesia. After excluding the most common causes of desaturation, fibreoptic bronchoscopy was performed through the tracheal tube and revealed complete collapse of the left main bronchus. The collapse persisted despite the application of positive end-expiratory pressure and several recruitment manoeuvres. After recovery of spontaneous ventilation, the collapse was lifted, and saturation increased back to normal levels. No evidence of extrinsic compression was found on chest X-rays or computed tomography scans.

Conclusion

Cases of unknown expiratory central airway collapse reported in the literature were usually managed with positive pressure ventilation. This approach has been unsuccessful in the case described herein. Our hypothesis is that mechanical bending of the left main bronchus occurred due to loss of the patient’s natural position and thoracic muscle tone under general anaesthesia with neuromuscular blockade. When possible, spontaneous ventilation should be maintained in patients with known or suspected ECAC.

Central airway obstruction: is it time to move forward?

INTRODUCTION

Central airway obstruction (CAO) represents a pathological condition that can lead to airflow limitation of the trachea, main stem bronchi, bronchus intermedius or lobar bronchus.

MAIN BODY

It is a common clinical situation consensually considered under-diagnosed. Management of patients with CAO can be difficult and deciding on the best treatment approach represents a medical challenge. This work intends to review CAO classifications, causes, treatments and its therapeutic limitations, approaching benign and malign presentations. Three illustrative cases are further presented, supporting the clinical problem under review.

CONCLUSION

Management of CAO still remains a challenge. The available options are not always effective nor free from complications. A new generation of costume-tailored airway stents, associated with stem cell-based therapy, could be an option in specific clinical situations.

Physiotherapy for large airway collapse: an ABC approach

Large airway collapse (LAC) describes the phenomenon of excessive, abnormal, inward movement of the large airways (i.e. trachea and/or main bronchi and/or bronchus intermedius) occurring during the expiratory phase of the respiratory cycle. It is an increasingly well-recognised problem and a prevalent comorbidity in other chronic respiratory conditions (e.g. COPD and asthma). LAC is associated with pervasive respiratory features such as a barking cough, exertional dyspnoea and an increased propensity to lower respiratory tract infection. These symptoms are unpleasant, and patients are often limited in their daily life and their function. The pathophysiology of this condition impairs airway clearance and can cause breathlessness and exercise intolerance, due to a loss of airway patency during expiratory flow. Dysfunctional adaptations to breathing and coughing may further amplify symptoms. This article provides, for the first time, clinically focused physiotherapeutic intervention advice based on our understanding of the pathophysiology of LAC, to support conservative management. It uses the available evidence from LAC, transferable evidence from other conditions and knowledge based on clinical experience. It proposes a practical "ABC model" to ensure physiotherapy assessment and treatments are centred around optimising three key clinical areas: Airways, including airway clearance and cough; Breathing, including breathlessness and breathing pattern; and Capacity for exercise, including an assessment of functional exercise ability.

Respiratory manifestations in the Ehlers-Danlos syndromes

Persons with the Ehlers-Danlos syndromes (EDS) report a wide range of respiratory symptoms, most commonly shortness of breath, exercise limitation, and cough. Also reported are noisy breathing attributed to asthma, difficulty with deep inhalation, and inspiratory thoracic pain. The literature consists of case reports and small cross-sectional and cohort studies. One case-control study estimated twofold to threefold greater respiratory disease burden among persons with EDS as compared to controls. The differential diagnosis for symptoms is broad. Structural alterations include pectus deformities, scoliosis, recurrent rib subluxations, and tracheobronchomalacia, associated with varying degrees of physiologic impairment. Those with vascular EDS have an increased risk of pneumothorax, intrapulmonary bleeding, cysts, and nonmalignant fibrous nodules. Functional aerodigestive manifestations such as inducible laryngeal obstruction may be misdiagnosed as asthma, with gastro-esophageal dysmotility and reflux as common contributing factors. Inflammatory manifestations include costochondritis, bronchiectasis, and localized respiratory allergic and nonallergic mast cell activation. Cranio-cervical instability can dysregulate respiratory control pathways. There is a need for careful phenotyping using standardized clinical tools and patient-reported outcomes and continuing collaboration with aerodigestive specialists including otolaryngologists and gastroenterologists. Also needed is further evaluation of respiratory symptoms in persons with hypermobility spectrum disorders. Personalized monitoring strategies are invaluable for interpretation and long-term management of respiratory symptoms.

Oral Positive Expiratory Pressure Device for Excessive Dynamic Airway Collapse Caused by Emphysema

Excessive dynamic airway collapse (EDAC) contributes to breathlessness and reduced quality of life in individuals with emphysema. We tested a novel, portable, oral positive expiratory pressure (o-PEP) device in a patient with emphysema and EDAC. MRI revealed expiratory tracheal narrowing to 80 mm² that increased to 170 mm² with the o-PEP device. After 2-weeks use of the o-PEP device for 33% to 66% of activities, breathlessness, quality of life, and exertional dyspnea improved compared with minimal clinically important differences (MCID): University of California-San Diego Shortness of Breath questionnaire score declined 69 to 42 (MCID, ≥5), St. George's Respiratory Questionnaire score decreased 71 to 27 (MCID, ≥4), and before and after the 6-minute walk test Borg score difference improved from Δ3 to Δ2 (MCID, ≥1). During the 6-minute walk test on room air without the use of the o-PEP device, oxyhemoglobin saturation declined 91% to 83%; whereas, with the o-PEP device, the nadir was 90%. Use of the o-PEP device reduced expiratory central airway collapse and improved dyspnea, quality of life, and exertional desaturation in a patient with EDAC and emphysema.

A Pilot Gene Expression and Histopathologic Analysis of Tracheal Resections in Tracheobronchomalacia

BACKGROUND

The airway structures and mRNA expression of genes that regulate airway inflammation and remodeling may be altered in the trachea of patients with tracheobronchomalacia (TBM).

METHODS

Fourteen tracheal specimens from 2005-to-2018 were used in this study. Surgical resection specimens from patients with TBM and tracheal stenosis (TS) were compared to control tracheal specimens obtained from autopsy cases. We investigated the mRNA expression of genes encoding fibroblast growth factor (FGF), binding protein 2 (FGFBP2), FGF receptor R3 (FGFR3), interleukin-1 beta (IL1β), tumor growth factor-beta 1 (TGFβ1), tissue inhibitor of metalloproteinases 1 (TIMP1), and intercellular adhesion molecule 1 (ICAM1), as well as established markers of airway inflammation including interferon-gamma (IFNγ) and tumor necrosis factor (TNF). The relative expression of target transcripts was assessed by qRT-PCR. A histological examination of the same resected airway specimens was performed on formalin-fixed paraffin embedded tissue sections.

RESULTS

FGFBP2 and FGFR3 showed higher expression in TBM compared to TS and control groups (p<0.05, p<0.01, respectively). Furthermore, both TGFβ1 and TIMP1 were elevated in TBM compared to controls (p<0.05). Conversely, ICAM1 was downregulated in TBM versus TS and controls (p<0.05). IL1β, IFNγ, and TNF were increased in TBM although did not achieve statistical significance. Histologically, compared to control airways, both TBM and TS demonstrated submucosal fibrotic changes, with TBM additionally demonstrating alterations in elastin fiber quality and density in the posterior membrane.

CONCLUSIONS

Significant changes in gene expression are observed in the tracheal walls of patients with TBM and TS compared to controls.

Complications of Lung Transplantation: Update on Imaging Manifestations and Management

As lung transplantation has become the most effective definitive treatment option for end-stage chronic respiratory diseases, yearly rates of this surgery have been steadily increasing. Despite improvement in surgical techniques and medical management of transplant recipients, complications from lung transplantation are a major cause of morbidity and mortality. Some of these complications can be classified on the basis of the time they typically occur after lung transplantation, while others may occur at any time. Imaging studies, in conjunction with clinical and laboratory evaluation, are key components in diagnosing and monitoring these conditions. Therefore, radiologists play a critical role in recognizing and communicating findings suggestive of lung transplantation complications. A description of imaging features of the most common lung transplantation complications, including surgical, medical, immunologic, and infectious complications, as well as an update on their management, will be reviewed here. Keywords: Pulmonary, Thorax, Surgery, Transplantation Supplemental material is available for this article. © RSNA, 2021.

Obese Patients Undergoing Tracheobronchoplasty Have Excellent Outcomes

BACKGROUND

Tracheobronchoplasty (TBP) is the gold-standard treatment for severe symptomatic excessive central airway collapse (ECAC), however outcomes among obese patients are unknown.

METHODS

A retrospective, single-center analysis was conducted on consecutive patients undergoing TBP for severe symptomatic ECAC from 2003 to 2020. Demographics, comorbidities, functional status, and peri-operative complications were collected. Functional status was assessed with a six-minute walk test (6MWT). Health-related quality of life (HRQOL) was assessed with the St. George's Respiratory Questionnaire (SGRQ), Cough-Specific Quality of Life Questionnaire (CSQL), and modified Medical Research Council dyspnea scale (mMRC) at baseline and post-operatively. Wilcoxon rank-sum and chi-squared tests were used to compare outcomes between groups. A mixed-effects regression model compared 6MWT and HRQOL over time.

RESULTS

One-hundred and three patients underwent TBP with complete follow-up data. Thirty-four patients (33%) were obese (BMI ≥ 35 kg/m²). Baseline demographics were similar between obese and non-obese groups, however obese patients had worse pre-operative SGRQ and mMRC. Overall complication rates were similar (52.9% vs. 43.5%, p=0.36). At 3-months, there was no significant difference in SGRQ, CSQL, or 6MWT, however, mMRC was higher in obese patients (p=0.04). At 12 months, there was no significant difference in SGRQ, CSQL, mMRC, or 6MWT. Correcting for age, sex, and Charlson Comorbidity Index, a mixed-effects regression model demonstrated obesity was not an independent predictor for lower 6MWT or HRQOL.

CONCLUSIONS

Obese patients achieve similar improvement in HRQOL and functional capacity with comparable morbidity following TBP as non-obese patients. Obesity should not preclude patients with severe symptomatic ECAC from TBP.

Argon Plasma Coagulation (APC) for the Treatment of Excessive Dynamic Airway Collapse (EDAC): An Animal Pilot Study

BACKGROUND

Surgical stabilization of the airway through tracheobronchoplasty (TBP) is the current treatment modality for patients with severe symptomatic excessive dynamic airway collapse. However, TBP is associated with increased morbidity and mortality. Bronchoscopic treatment of the posterior membrane using argon plasma coagulation (APC) may be a safer alternative to TBP in highly selected patients. This study aimed to evaluate the effect of APC in the tracheobronchial tree of a sheep animal model.

PATIENTS AND METHODS

Two adult sheep were used for this study. Under flexible bronchoscopy, the posterior tracheal membrane was treated with precise APC using different power settings. Chest computed tomography was done at 2 days and bronchoscopy was performed at 30 days following initial procedure, before euthanasia. The airways were assessed for the presence of treatment-related histopathologic changes along with expression of genes associated with fibrosis.

RESULTS

There was no perioperative or postoperative morbidity or mortality. Chest computed tomography showed no signs of pneumomediastinum or pneumothorax. Flexible bronchoscopy showed adequate tracheobronchial tissue healing process, independent of the power settings used. Histologic changes demonstrated an increased extent of fibroblastic collagen deposition in the treated posterior membrane when higher power settings were used. In a similar manner, APC treatment managed to activate fibrosis-associated gene transcription factors, with higher settings achieving a higher level of expression.

CONCLUSION

APC at high-power settings achieved higher levels of fibroblast collagen deposition at the posterior membrane and higher expression of fibrosis-associated gene transcription factors, when compared with lower settings.

An unusual case of breathlessness

We present the case of an asthmatic patient who continued to present with breathlessness and received multiple courses of steroids for her presumed asthma exacerbations. After multiple investigations, we made the diagnosis of TBM secondary to relapsing polychondritis. https://bit.ly/3b8Uw1O.

Approach to the Patient with Cough

Cough is a common presenting symptom for patients in a primary care setting. Chronic cough is defined as a cough lasting for more than 8 weeks. The most common causes of chronic cough are upper airway cough syndrome, asthma, and gastroesophageal reflux disease. Detailed history and physical examination are critical in identifying potential etiologies of cough. When there is no prevailing diagnosis, step-wise empiric trial of medication is a strategic and cost-effective approach. Certain features of chronic cough should provoke an expedited and invasive diagnostic strategy. Effectively treating patients with chronic cough has a high impact on quality of life.

Single-Lumen Endotracheal Tube and Bronchial Blocker for Airway Management During Tracheobronchoplasty for Tracheobronchomalacia: A Case Report

We present a case of a 69-year-old man who underwent tracheobronchoplasty for tracheobronchomalacia using a single-lumen endotracheal tube and a Y-shaped bronchial blocker for airway management. Tracheobronchoplasty is performed by sewing mesh to plicate the posterior, membranous wall of the distal trachea and main bronchi through a right posterolateral thoracotomy. The goals of airway management include continuous left-lung ventilation and lung protection from aspiration. Ideally, only conventional airway management tools are used. This case demonstrates that a single-lumen endotracheal tube with a bronchial blocker can be a straightforward strategy for airway management during tracheobronchoplasty.

Central Airway Collapse, an Underappreciated Cause of Respiratory Morbidity

Dyspnea, cough, sputum production, and recurrent respiratory infections are frequently encountered clinical concerns leading patients to seek medical care. It is not unusual for a well-defined etiology to remain elusive or for the therapeutics of a presumed etiology to be incompletely effective. Either scenario should prompt consideration of central airway pathology as a contributor to clinical manifestations. Over the past decade, recognition of dynamic central airway collapse during respiration associated with multiple respiratory symptoms has become more commonly appreciated. Expiratory central airway collapse may represent the answer to this diagnostic void. Expiratory central airway collapse is an underdiagnosed disorder that can coexist with and mimic asthma, chronic obstructive pulmonary disease, and bronchiectasis. Awareness of expiratory central airway collapse and its spectrum of symptoms is paramount to its recognition. This review includes clear definitions, diagnostics, and therapeutics for this challenging condition. We performed a narrative review through the PubMed (MEDLINE) database using the following MeSH terms: airway collapse, tracheobronchomalacia, tracheomalacia, and bronchomalacia. We include reports from systematic reviews, narrative reviews, clinical trials, and observational studies from 2005 to 2020. Two reviewers evaluated potential references. No systematic reviews were found. A total of 28 references were included into our review. Included studies report experience in the diagnosis and/or treatment of dynamic central airway collapse; case reports and non-English or non-Spanish studies were excluded. We describe the current diagnostic dilemma, highlighting the role of dynamic bronchoscopy and tracheobronchial stent trial; outline the complex therapeutic options (eg, tracheobronchoplasty); and present future directions and challenges.

Quality of life outcomes in tracheobronchomalacia surgery

Tracheobronchomalacia (TBM) is an obstructive airway disease characterized by laxity and redundancy of the posterior membrane of the main airways leading to dynamic airway collapse during exhalation. The gold standard for diagnosis is dynamic computed tomography (DCT) scan and dynamic flexible bronchoscopy (DFB). Patients with complete or near-complete collapse (>90% reduction in cross-sectional area) of the airway are possible candidates for surgical management. Central airway stabilization by tracheobronchoplasty (TBP) effectively corrects malacic airways and has demonstrated significant improvement in objective functional measures, which is often but not uniformly accompanied by equal improvement in health-related quality of life (HRQOL) metrics. This article reviews HRQOL instruments used to report outcomes after TBM surgery.

Expiratory central airway collapse - an overlooked entity?: Two case reports

INTRODUCTION

Expiratory central airway collapse is defined by excessive inward bulging of either tracheobronchial posterior membrane or cartilage. The former is called excessive dynamic airway collapse (EDAC), and the latter, depending on the site of collapse, tracheomalacia, bronchomalacia or tracheobronchomalacia. Due to their non-specific symptoms and lack of awareness amongst clinicians they tend to be mislabeled as common obstructive lung disorders, or complicate their course undetected. Particular controversies refer to EDAC sometimes considered just as a symptom of obstructive lung disease and not a separate entity. Nonetheless, a growing body of evidence indicates that EDAC might be present in patients without apparent obstructive lung disease or it might be an independent risk factor in chronic obstructive pulmonary disease or asthma patients.

PATIENT CONCERNS

Patient #1 was admitted because of idiopathic chronic cough whereas patient #2 was admitted for differential diagnosis of dyspnea of uncertain etiology. In both patients symptoms were unresponsive to bronchodilators and inhaled corticosteroids.

FINDINGS AND DIAGNOSIS

In both patients an excess collapse of tracheobronchial posterior membrane was detected during bronchoscopy; in patient #1, of right main bronchus and right upper lobe bronchus and in patient #2 of right upper lobe bronchus and both main bronchi. Excess central airway collapse in patient #2 was also visualized on expiratory chest CT. In patient #1 spirometry did not reveal obturation, whereas in patient #2 only mild, irreversible, obstruction was revealed, disproportionate to patients significant breathlessness.

INTERVENTIONS

Both patients were treated with N-acetylcysteine and adjustable positive expiratory pressure valves.

OUTCOMES

Due to aforementioned treatment chronic cough in patient #1 subsided almost completely whereas patient's #2 dyspnea improved significantly.

CONCLUSIONS

In presented cases EDAC was an unexpected finding, even though, it firmly corresponded with reported symptoms. Treatment modification led to improvement of patients quality of life.

Care recommendations for the respiratory complications of esophageal atresia-tracheoesophageal fistula

Tracheoesophageal fistula (TEF) with esophageal atresia (EA) is a common congenital anomaly that is associated with significant respiratory morbidity throughout life. The objective of this document is to provide a framework for the diagnosis and management of the respiratory complications that are associated with the condition. As there are no randomized controlled studies on the subject, a group of experts used a modification of the Rand Appropriateness Method to describe the various aspects of the condition in terms of their relative importance, and to rate the available diagnostic methods and therapeutic interventions on the basis of their appropriateness and necessity. Specific recommendations were formulated and reported as Level A, B, and C based on whether they were based on "strong", "moderate" or "weak" agreement. The tracheomalacia that exists in the site of the fistula was considered the main abnormality that predisposes to all other respiratory complications due to airway collapse and impaired clearance of secretions. Aspiration due to impaired airway protection reflexes is the main underlying contributing mechanism. Flexible bronchoscopy is the main diagnostic modality, aided by imaging modalities, especially CT scans of the chest. Noninvasive positive airway pressure support, surgical techniques such as tracheopexy and rarely tracheostomy are required for the management of severe tracheomalacia. Regular long-term follow-up by a multidisciplinary team was considered imperative. Specific templates outlining the elements of the clinical respiratory evaluation according to the patients' age were also developed.

Longitudinal Follow-up of Patients With Tracheobronchomalacia After Undergoing Tracheobronchoplasty: Computed Tomography Findings and Clinical Correlation

PURPOSE

The purpose of this study was to evaluate intermediate and long-term changes in expiratory tracheal collapsibility by computed tomography (CT) in patients with tracheobronchomalacia following surgical treatment with tracheobronchoplasty and to correlate CT findings with clinical findings.

MATERIALS AND METHODS

Between 2003 and 2016, 18 patients with tracheobronchomalacia underwent tracheobronchoplasty and were imaged preoperatively and postoperatively at both intermediate and long-term intervals. Imaging included end-inspiratory and dynamic expiratory phase scans. The cross-sectional area of the airway lumen was measured at 2 standard levels (1 cm above the aortic arch and carina). These measurements were used to calculate % collapsibility. Clinical findings recorded included a questionnaire on symptomatology and a 6-minute walk test.

RESULTS

Before surgery, expiratory collapsibility of the upper trachea was 72%±25% (mean±SD) and that of the lower trachea was 68%±22%. On intermediate follow-up (mean, 1.5 y), collapsibility significantly decreased to 37%±21% at the upper trachea and 35%±19% at the lower trachea (P<0.001). On long-term follow-up (mean, 6 y), collapsibility increased to 51%±20% at the upper trachea and 47%±17% at the lower trachea and was significantly worse than on intermediate follow-up (P=0.002). However, collapsibility on long-term follow-up remained significantly lower than preoperative collapsibility (P=0.015). Clinical findings showed a similar trend as quantitative CT measurements.

CONCLUSION

Expiratory tracheal collapsibility substantially decreases after tracheobronchoplasty on intermediate follow-up. At long-term follow-up, tracheal collapsibility shows a modest increase, but remains significantly lower than the preoperative baseline. Quantitative measurements from dynamic CT have the potential to play an important role as imaging biomarkers for assessing response to tracheobronchoplasty.