Tracheobronchomalacia and excessive dynamic airway collapse

Airway malacia in chronic obstructive pulmonary disease: prevalence, morphology and relationship with emphysema, bronchiectasis and bronchial wall thickening

The aim of this study was to determine the prevalence of airway malacia and its relationship with ancillary morphologic features in patients with chronic obstructive pulmonary disease (COPD). A retrospective review was performed of a consecutive series of patients with COPD who were imaged with inspiratory and dynamic expiratory multidetector computed tomography (MDCT). Airway malacia was defined as > or =50% expiratory reduction of the airway lumen. Both distribution and morphology of airway malacia were assessed. The extent of emphysema, extent of bronchiectasis and severity of bronchial wall thickness were quantified. The final study cohort was comprised of 71 patients. Airway malacia was seen in 38 of 71 patients (53%), and such proportion was roughly maintained in each stage of COPD severity. Almost all tracheomalacia cases (23/25, 92%) were characterised by an expiratory anterior bowing of the posterior membranous wall. Both emphysema and bronchiectasis extent did not differ between patients with and without airway malacia (p > 0.05). Bronchial wall thickness severity was significantly higher in patients with airway malacia and correlated with the degree of maximal bronchial collapse (p < 0.05). In conclusion, we demonstrated a strong association between airway malacia and COPD, disclosing a significant relationship with bronchial wall thickening.

Congenital airway lesions and lung disease

Structural upper and lower airway disorders and parenchymal disorders are uncommon in pediatric practice, but many pediatricians will encounter them and be responsible for the ongoing care of these patients. Pediatricians need to be cognizant of these diagnoses because, even though management of these disorders generally lacks an evidence base, existing principles of good care surrounding accurate diagnosis, classifications of severity, judicious use of investigations, medication, and surgical approaches are essential to good outcomes.

Longitudinal quantification of growth and changes in primary tracheobronchomalacia sites in children

RATIONALE

Longitudinal follow-up of children with tracheobronchomalacia is essential to improving our understanding of these disorders, yet currently, there is no such data.

OBJECTIVES

To longitudinally define malacia sites and quantify the cross-sectional area (CSA) of the lumen using a bronchoscopic technique and to relate these measurements to illness profiles.

METHODS

The validated color histogram mode technique was utilized to quantify primary malacia lesions and airway sites' CSA. Illness frequency, validated scales of illness and cough diary scores were prospectively used to assess clinical profiles.

RESULTS

Thirty-five malacia sites were defined from the 2 studies of 21 children. CSA of 21 (60%) of the malacia lesions increased, 5 (14%) new lesions appeared, 5 (14%) decreased in size, 3 (8%) remained unchanged, and 1(3%) was indeterminate. Overall there was no statistically significant change in paired-data assessments of malacia sites' area while there was a significant increase in area of non-malacia sites. The median yearly growth rate for the malacia sites and non-malacia was 3.65 mm2/year sites and 5.38 mm2/year, respectively (P = 0.31). The type and severity of lesion was not associated with any difference in growth rates, illness frequency or clinical scores.

CONCLUSIONS

Malacia lesions increase in size at the same rate as non-malacia sites. However malacia may worsen and new primary lesions may develop. Neither malacia type nor severity influences their growth pattern or illness profile.

Description of a multidimensional classification system for patients with expiratory central airway collapse

BACKGROUND AND OBJECTIVE

Patients with expiratory central airway collapse present with various symptoms, aetiologies, morphologies, extent and severity of airway collapse. The aim of this study was to delineate a multidimensional classification system and common language for evaluating patients with expiratory central airway collapse.

METHODS

The classification system was based on the morphology and origin of the airway abnormality as well as stratification parameters such as functional status, extent and severity of airway collapse. Patients with expiratory central airway collapse who underwent clinical and bronchoscopic examination before and after treatment were identified from a bronchoscopy database. The classification was applied to the study patients before and after treatment to assess the utility of this stratification approach.

RESULTS

Eighteen patients were studied. Four had excessive dynamic airway collapse and 14 had tracheobronchomalacia. Post-treatment, functional status improved by one class in 12 patients, by two classes in four patients and remained unchanged in two. Severity of airway collapse improved in 15 and remained unchanged in three patients. The extent of abnormality diminished in 14 patients and did not change in four.

CONCLUSIONS

Using this classification, the morphologies and aetiologies of expiratory central airway collapse are identified, and an objective stratification of patients according to degree of functional impairment, extent of disease and severity of airway collapse is possible.

The role of chest radiography and computed tomography in the diagnosis and management of asthma

PURPOSE OF REVIEW

The management of asthma is guided by clinical symptoms, physiological measurements, and response to therapy. Recent advances in computed tomography imaging promise to add a new dimension to our diagnostic armamentarium. Accurate representation of airway pathology, visualized by high-resolution chest computed tomography scan, helps to improve the understanding of the pathophysiology of asthma. In addition, findings on computed tomography may help to guide therapies for asthma. As radiologists provide us with sophisticated modalities that may also have a bearing on treatment, clinicians should stay abreast of this evolving noninvasive technology.

RECENT FINDINGS

This review focuses on the findings seen on computed tomography imaging as related to asthma. Airway wall thickness is discussed and how it relates to disease progression and pulmonary function test. In addition, indirect findings such as bronchial dilatation and mosaic attenuation, both consequences of air-trapping, are discussed. Other investigational tools, such as endobronchial ultrasound and positron emission tomography, are described.

SUMMARY

New modalities in radiology hold promise to aid in the understanding and treatment of small-airway disease. Although still considered investigational modalities, research evidence is fast accumulating. It behooves the clinician to have a heightened awareness regarding further advancements in this field.

Comparison of natural and Dumon airway stents for the management of benign tracheobronchial stenoses

OBJECTIVE AND BACKGROUND

To investigate the utility and safety of the 'Natural stent', a newly designed silicone airway stent, the authors compared clinical outcomes and complications in patients who underwent silicone airway stenting for the management of benign airway stenosis.

METHODS

The medical records of 94 patients requiring the placement of 100 airway stents (43 Dumon and 57 Natural) were retrospectively reviewed in a tertiary referral hospital.

RESULTS

Post-tuberculous stenosis was the leading indication for airway stenting (74%), followed by post-intubation stenosis (21%). After intervention, dyspnoea improved in patients who underwent Dumon (90%) and Natural (86%) stenting. After stabilizing dyspnoea, stents could be successfully removed in half of the patients who underwent Dumon (54%) or Natural (49%) stenting. During a 42-month follow-up period, complication rates were similar in patients who underwent Dumon or Natural stenting.

CONCLUSION

Natural airway stent was as effective and safe as Dumon stent for the management of benign tracheobronchial stenoses.