Endobronchial Ultrasound is Useful in the Assessment of Bronchial Wall Changes Related to Bronchial Thermoplasty

Background

Bronchial thermoplasty (BT) is an interventional endoscopic treatment for severe asthma leading to the clinical improvement, but morphologic changes of bronchial wall related to the procedure and predictors of a favorable response to BT remain uncertain. The aim of the study was to validate an endobronchial ultrasound (EBUS) in assessing the effectiveness of BT treatment.

Methods

Patients with severe asthma who met the clinical criteria for BT were included. In all patients clinical data, ACT and AQLQ questionnaires, laboratory tests, pulmonary function tests and bronchoscopy with radial probe EBUS and bronchial biopsies were collected. BT was performed in patients with the thickest bronchial wall L₂ layer representing ASM. These patients were evaluated before and after 12 months of follow-up. The relationship between baseline parameters and clinical response was explored.

Results

Forty patients with severe asthma were enrolled to the study. All 11 patients qualified to BT successfully completed the 3 sessions of bronchoscopy. BT improved asthma control (P=0.006), quality of life (P=0.028) and decreased exacerbation rate (P=0.005). Eight of the 11 patients (72.7%) showed a clinically meaningful improvement. BT also led to a significant decrease in the thicknesses of bronchial wall layers in EBUS (L₁ decreased from 0.183 to 0.173 mm, P=0.003; L₂ from 0.207 to 0.185 mm, P = 0.003; and L_3-5 from 0.969 to 0.886 mm, P=0.003). Median ASM mass decreased by 61.8% (P=0.002). However, there was no association between baseline patient characteristics and the magnitude of clinical improvement after BT.

Conclusion

BT was associated with a significant decrease in the thickness of the bronchial wall layers measured by EBUS including L₂ layer representing ASM and ASM mass reduction in bronchial biopsy. EBUS can assess bronchial structural changes related to BT; however, it did not predict the favorable clinical response to therapy.

Assessment of Airway Remodeling Using Endobronchial Ultrasound in Asthma-COPD Overlap

Purpose

The aim of this study was to evaluate the structural changes of the airways using the endobronchial ultrasound (EBUS) in ACO patients compared to severe asthma and COPD patients.

Patients and Methods

The study included 17 patients with ACO, 17 patients with COPD and 33 patients with severe asthma. Detailed clinical data were obtained from all participants. Basic laboratory tests were performed, including measurement of eosinophil counts in blood and serum immunoglobulin E (IgE) concentrations. All patients underwent spirometry and bronchoscopy with EBUS (a 20‑MHz ultrasound probe) to measure the total thicknesses of the bronchial walls and their particular layers in segmental bronchi of the right lower lobe. EBUS allows to distinguish five layers of the bronchial wall. Layer 1 (L₁) and layer 2 (L₂) were analyzed separately, while the outer layers (layers 3–5 [L_3–5]) that correspond to cartilage were assessed together.

Results

In patients with ACO the thicknesses of the L₁ and L₂ layers, which are mainly responsible for remodeling, were significantly greater than in patients with COPD and significantly smaller than in patients with severe asthma (median L₁= 0.17 mm vs 0.16 mm vs 0.18 mm, p<0.001; median L₂= 0.18 mm vs 0.17 mm vs 0.20 mm, p<0.001, respectively). The thicknesses of the total bronchial walls (L₁+L₂+L_3–5) and L_3–5 were significantly smaller in ACO and COPD patients compared to asthma patients (median L₁+L₂+L_3–5= 1.2 mm vs 1.14 mm vs 1.31 mm, p<0.001; median L_3–5= 0.85 mm vs, 0.81 mm vs 0.92 mm, p=0.001, respectively).

Conclusion

The process of structural changes in the airways assessed by EBUS is more advanced in individuals with ACO compared to patients with COPD, and less pronounced compared to patients with severe asthma. It seems that EBUS may provide useful information about differences in airway remodeling between ACO, COPD and severe asthma.

Relationship between the thickness of bronchial wall layers, emphysema score, and markers of remodeling in bronchoalveolar lavage fluid in patients with chronic obstructive pulmonary disease

INTRODUCTION    Airway remodeling plays an important role in the development of chronic obstructive pulmonary disease (COPD). Imaging methods, such as computed tomography (CT) and endobronchial ultrasound (EBUS), may be useful in the assessment of structural alterations in the lungs. OBJECTIVES    The aim of this study was to evaluate a relationship between the severity of emphysema assessed by chest CT, the thickness of bronchial wall layers measured by EBUS, and the markers of remodeling in bronchoalveolar lavage fluid (BALF) in patients with COPD. PATIENTS AND METHODS    The study included 33 patients with COPD who underwent pulmonary function tests, emphysema score assessment by chest CT, as well as bronchofiberoscopy with EBUS in order to measure the total bronchial wall thickness and, separately, layers L1, L2, and L3-5. Selected remodeling (matrix metalloproteinase 9 [MMP-9], tissue inhibitor of metalloproteinase 1, transforming growth factor β1 [TGF-β1]) and inflammatory markers (neutrophil elastase, eosinophil cationic protein) were measured in BALF samples using an enzyme-linked immunosorbent assay. RESULTS    MMP-9 levels in BALF were significantly higher in patients with very severe bronchial obstruction than in those with moderate and mild bronchial obstruction (P = 0.02), and showed a negative correlation with forced expiratory volume in 1 second (r = -0.538, P = 0.002). The thickness of L1 and L2, which histologically correspond to the mucosa, submucosa, and smooth muscle, demonstrated a positive correlation with TGF-β1 levels in BALF (r = 0.366, P = 0.046 and r = 0.425, P = 0.02) and the thickness of L1 showed a negative association with neutrophil elastase levels (r = -0.508, P = 0.004). There was no significant correlation between the analyzed markers in BALF and the emphysema score. CONCLUSIONS    Significant correlations of TGF-β1 and elastase with the thickness of bronchial wall layers, and of MMP-9 with the severity of obstruction, may suggest the involvement of these markers in airway remodeling in patients with COPD.

Assessment of remodeling in chronic obstructive pulmonary disease using imaging methods

INTRODUCTION

While spirometry plays a key role in diagnosing chronic obstructive pulmonary disease (COPD), imaging methods including endobronchial ultrasound (EBUS) and chest computed tomography (CT) appear to be useful for investigating structural changes in the lungs.

OBJECTIVES

The aim of this study was to evaluate remodeling in COPD patients using EBUS and chest CT.

PATIENTS AND METHODS

The study included 33 patients with COPD, 15 patients with severe asthma, and 15 control subjects. All subjects underwent pulmonary function tests and bronchoscopy with EBUS to measure the total thickness of the bronchial wall and its layers. Additionally, in COPD patients, a chest CT was performed to measure total bronchial wall thickness.

RESULTS

The total bronchial wall thickness measured by EBUS in patients with COPD (1.192 ±0.079 mm) was significantly smaller than that in asthmatic patients (1.433 ±0.230 mm, P = 0.001) and significantly greater than in control subjects (1.099 ±0.095 mm, P = 0.04), and was positively correlated with residual volume (RV) / total lung capacity (r = 0.5, P = 0.02), RV (r = 0.6, P = 0.007), and RV (%) (r = 0.5, P = 0.05). The thickness of the bronchial wall layers in patients with COPD were as follows: L1 = 0.135 ±0.018 mm, L2 = 0.151 ±0.026 mm, and L3-5 = 0.906 ±0.065 mm. There was no correlation between the thickness of the bronchial wall layers and forced expiratory volume in 1 second.

CONCLUSIONS

The results of this study show that EBUS is a useful method for evaluating bronchial wall layers not only in asthma but also in COPD, and suggest that the pattern of remodeling differs in each of these diseases.

Integration of Image and Laser Scanning Data Based on Selected Example

The paper aims at presentation of results of research on integration of image and laser data based on selected example. Since a few years the authors have been conducting research on processing image data, and those obtained from laser scanning in the form of the so-called point cloud. In experiments data from terrestrial and mobile laser scanning gained for two different objects were compared: a parish house from Goźlice located in the open-air ethnographic museum at the village of Tokarnia, Poland, and part of the Cracow-Warsaw railway line. The results of those experiments proved that data in the form of point cloud were not always sufficient for a precise 3D model reconstruction. Supplementing point clouds with photogrammetric images seems to be the best solution.

The use of endobronchial ultrasonography in assessment of bronchial wall remodeling in patients with asthma

BACKGROUND

Endobronchial ultrasound (EBUS) is a new technique that enables the assessment of bronchial wall layers. The aim of the study was to verify the utility of EBUS for the assessment of bronchial wall remodeling in patients with asthma.

METHODS

In 35 patients with asthma and 23 control subjects, high-resolution CT (HRCT) scanning and EBUS were used to measure bronchial wall thickness in the 10th segment of the right lung. With a radial 20-MHz probe, EBUS identified the 5-laminar structure of the bronchial wall. Layer 1 (L(1)) and layer 2 (L(2)) were analyzed separately, and layers 3 through 5 (L(3-5)), which corresponded to cartilage, were analyzed jointly. Digitalized EBUS images were used for the quantitative assessment of bronchial wall thickness and the wall area (WA) of the layers. Finally, bronchial biopsy specimens were taken for measuring the thickness of the reticular basement membrane (RBM). The thickness and WA of the bronchial wall layers, which were assessed using EBUS, were correlated with FEV(1) and RBM.

RESULTS

There was no significant difference in the measurements of total bronchial wall thickness using EBUS and HRCT scanning. The thickness and WA of the bronchial wall and its layers were significantly greater in patients with asthma than in the control subjects. A negative correlation among the thicknesses of L(1), L(2), and L(3-5) and FEV(1), and a positive correlation with RBM were observed only in the patients with asthma.

CONCLUSIONS

EBUS allows precise measurement of the thickness and WA of bronchial wall layers. The correlation of these parameters with asthma severity suggests implementation of EBUS in the assessment of bronchial wall remodeling in patients with asthma.