Incomplete fissures in severe emphysematous patients evaluated with MDCT: Incidence and interobserver agreement among radiologists and pneumologists

The Prediction of Fissure Integrity by Quantitative Computed Tomography Analysis

BACKGROUND

Incomplete interlobar fissure may increase the difficulty of thoracoscopic lobectomy. Herein, we compared the accuracy of visual versus quantitative analysis to predict fissure integrity in lung cancer patients undergoing thoracoscopic lobectomy and evaluated the effects of fissure integrity on surgical outcome.

METHODS

This was a single-center retrospective study including consecutive patients undergoing VATS (video-assisted thoracoscopic surgery) lobectomy for lung cancer. The target interlobar fissures were classified as complete or incomplete by visual and quantitative analysis. Using the intraoperative finding as the reference method, the diagnostic accuracy of the two methods to define fissure completeness (dependent variable) was calculated and statistically compared. Yet, we evaluated differences in postoperative outcomes between patients with complete and incomplete fissure integrity.

RESULTS

A total of 93 patients were included in the study; 33/93 (36%) presented complete fissure. Visual and quantitative analyses correctly identified complete fissure in 19/33 (57%) and 29/33 (88%) patients, respectively, and incomplete fissure in 56/60 (93%) and 58/60 (96%) patients, respectively. Quantitative analysis had better diagnostic accuracy than visual analysis (81 vs. 93%; p = 0.01). Patients with incomplete fissure compared with those with complete fissure had a higher conversion rate (6 vs. 13%; p = 0.43), higher persistent air leak rate (0/33 vs. 14/60; p = 0.03), and longer hospitalization (12.6 ± 3.8 vs. 7.1 ± 2.4 days; p = 0.01).

CONCLUSION

Quantitative analysis accurately predicted the fissures' integrity; it may be useful for selecting suitable cases for thoracoscopic lobectomy especially for surgeons with limited minimally invasive experience.

HRCT characteristics of severe emphysema patients: Interobserver variability among expert readers and comparison with quantitative software

PURPOSE

For a successful bronchoscopic lung volume reduction coil treatment it is important to place the coils in the most emphysematous lobes. Therefore assessment of the lobe with greatest destruction is essential. Our aims were to investigate the level of agreement among expert reviewers of HRCT-scans in emphysema patients and the comparison with QCT (quantitative computed tomography) software.

METHOD

Five experienced CT-assessors, conducted a visual assessment of the baseline HRCT-scans of emphysema patients who participated in the RENEW bronchoscopic lung volume reduction coil study. On the same HRCT-scans, a QCT analysis was performed.

RESULTS

In total 134 HRCT-scans were rated by all 5 experts. All 5 CT-assessors agreed on which was the most destructed lobe in 61 % of the left lungs (ƙ:0.459) and 60 % of the right lungs (ƙ:0.370). The consensus of the 5 assessors matched the QCT in the left lung for 77 % of the patients (ƙ:0.425) and in the right lung for 82 % (ƙ:0.524).

CONCLUSIONS

Our results show that the interobserver agreement between five expert CT-assessors was only fair to moderate when evaluating the most destructed lobe. CT-assessor consensus improved matching with QCT determination of lobar destruction compared to individual assessor determinations. Because some CT-features are associated with treatment outcomes and important for optimal patient selection of bronchoscopic lung volume reduction treatment, we recommend including more than one CT-reviewer and supported by QCT measurements.

Advances in imaging for lung emphysema

Lung emphysema represents a major public health burden and still accounts for five percent of all deaths worldwide. Hence, it is essential to further understand this disease in order to develop effective diagnostic and therapeutic strategies. Lung emphysema is an irreversible enlargement of the airways distal to the terminal bronchi (i.e., the alveoli) due to the destruction of the alveolar walls. The two most important causes of emphysema are (I) smoking and (II) α1-antitrypsin-deficiency. In the former lung emphysema is predominant in the upper lung parts, the latter is characterized by a predominance in the basal areas of the lungs. Since quantification and evaluation of the distribution of lung emphysema is crucial in treatment planning, imaging plays a central role. Imaging modalities in lung emphysema are manifold: computed tomography (CT) imaging is nowadays the gold standard. However, emerging imaging techniques like dynamic or functional magnetic resonance imaging (MRI), scintigraphy and lately also the implementation of radiomics and artificial intelligence are more and more diffused in the evaluation, diagnosis and quantification of lung emphysema. The aim of this review is to shortly present the different subtypes of lung emphysema, to give an overview on prediction and risk assessment in emphysematous disease and to discuss not only the traditional, but also the new imaging techniques for diagnosis, quantification and evaluation of lung emphysema.

Bronchoscopic interventions for emphysema: Current status

Chronic obstructive pulmonary disease is a prevalent and progressive disease. The recently developed bronchoscopic lung volume reduction (BLVR) techniques offer personalized therapeutic options in subgroups of patients with severe emphysema. Endobronchial and intrabronchial valves (EBV/IBV) achieve lung volume reduction by lobar atelectasis. The lung volume reduction coils (LVRCs) and bronchoscopic thermal vapor ablation (BTVA) induce tissue compression, either mechanically or through inflammatory processes. While the effects of EBV/IBV are reversible by removing the implants, the effects of LVRC are partially reversible and that of BTVA is irreversible. The presence of interlobar collateral ventilation (CV) impacts on EBV/IBV treatment outcome due to its mechanism of action. Therefore, using radiological and endoscopic techniques to assess CV has a vital importance. Current evidence of BLVR demonstrates acceptable safety and short-term clinical efficacy. However, head-to-head trials are lacking, and further research is needed to establish long-term clinical benefit, durability, and cost-effectiveness of these techniques.

Emerging Interventional Pulmonary Therapies for Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease is a condition characterized by progressive airflow limitation caused by airway and parenchymal inflammation. Current medical therapies, including bronchodilators, corticosteroids, and anti-inflammatory medications, have been shown to variably improve pulmonary function or quality of life without providing a long-term mortality benefit. Mortality benefits to therapy have been demonstrated in only 2 therapeutic interventions to date: long-term use of daily supplemental oxygen and surgical lung volume reduction (LVRS) for upper-lobe-predominant disease in patients with a low baseline exercise capacity. Newer bronchoscopic techniques for lung volume reduction (bLVR) have attracted interest from clinicians and researchers. To achieve successful results, these advanced therapies require an interdisciplinary approach between general and interventional pulmonologists and thoracic radiologists. In this article, we aim to review the latest interventional pulmonary techniques for treatment of chronic obstructive pulmonary disease with an emphasis on bLVR. We will review the bLVR preprocedure imaging evaluation, postprocedure imaging findings, and explore the potential benefits and risks of therapy based on the most recent clinical trial evidence.

The STELVIO trial, a game changer for bronchoscopic lung volume reduction in patients with severe emphysema

Chronic obstructive pulmonary disease (COPD) is characterised by persistent respiratory symptoms and airflow limitation, which is caused by small airway disease (bronchiolitis) and alveolar destruction (emphysema) [1]. Patients primarily suffering from severe emphysema are often limited in exercise capacity due to the consequences of hyperinflation [2].

The STELVIO trial was crucial to ensure that bronchoscopic lung volume reduction using one-way valves has evolved from an experimental intervention into a state-of-the-art treatment option for specific patients with advanced emphysemahttp://bit.ly/2IgMrsp

An open-source framework for pulmonary fissure completeness assessment

We present an open-source framework for pulmonary fissure completeness assessment. Fissure incompleteness has been shown to associate with emphysema treatment outcomes, motivating the development of tools that facilitate completeness estimation. Generally, the task of fissure completeness assessment requires accurate detection of fissures and definition of the boundary surfaces separating the lung lobes. The framework we describe acknowledges a) the modular nature of fissure detection and lung lobe segmentation (lobe boundary detection), and b) that methods to address these challenges are varied and continually developing. It is designed to be readily deployable on existing lung lobe segmentation and fissure detection data sets. The framework consists of multiple components: a flexible quality control module that enables rapid assessment of lung lobe segmentations, an interactive lobe segmentation tool exposed through 3D Slicer for handling challenging cases, a flexible fissure representation using particles-based sampling that can handle fissure feature-strength or binary fissure detection images, and a module that performs fissure completeness estimation using voxel counting and a novel surface area estimation approach. We demonstrate the usage of the proposed framework by deploying on 100 cases exhibiting various levels of fissure completeness. We compare the two completeness level approaches and also compare to visual reads. The code is available to the community via github as part of the Chest Imaging Platform and a 3D Slicer extension module.

Changes in ventilation and perfusion following lower lobe endoscopic lung volume reduction (ELVR) with endobronchial valves in severe COPD

BACKGROUND

We have previously reported significant improvements in ventilation and perfusion (VQ) and V/Q matching in the contralateral lung, especially the non-targeted lower zone in patients with severe COPD following upper lobe ELVR with endobronchial valves. However, V/Q changes after lower lobe ELVR have not been described.

METHODS

Seven patients with lower lobe heterogeneous emphysema underwent unilateral lower lobe ELVR at Macquarie University Hospital. Lung function tests, 6-minute walk tests (6MWT), St George's Respiratory Questionnaire (SGRQ) and planar differential VQ scans were performed at baseline and at 1, 3 and 12 months post-ELVR.

RESULTS

Compared to baseline, patients showed significant improvements in FEV1 (0.83 ± 0.09L-0.97 ± 0.12L, p < 0.05), 6MWD (200.33 ± 56.54 m-274.24 ± 48.03 m, p < 0.05) and SGRQ (61.13 ± 5.33-42.86 ± 6.99, p < 0.05) at 3 months after ELVR. This improvement was maintained at 12 months. There was a corresponding significant improvement in the differential ventilation (30.21 ± 3.04%-37.82 ± 3.76%, p < 0.05) and perfusion (31.77 ± 2.53%-35.60 ± 2.58%, p < 0.05) of the contralateral non-targeted upper zone.

CONCLUSIONS

Within the limitations of a small sample size, we have found that in heterogeneous severe COPD patients undergoing ELVR targeting the lower lobes, there are clinical and PFT improvements similar to that reported in ELVR targeting upper lobes. Contralateral improvement in V/Q matching also occurs following lower lobe ELVR with the greatest improvement in the contralateral upper zone, suggesting the contralateral upper lobe should be the least affected lobe if the lower lobe is targeted in ELVR. These findings need to be confirmed in a study with a larger number of patients.

Predictors of Response to Endobronchial Coil Therapy in Patients With Advanced Emphysema

BACKGROUND

The Lung Volume Reduction Coil Treatment in Patients With Emphysema (RENEW) trial reported improvements in quality of life, pulmonary function, and exercise performance following endobronchial coil treatment.

OBJECTIVES

The purpose of this post hoc analysis was to identify baseline predictors, including quantitative CT measures, that identify patients most likely to significantly benefit from endobronchial coil therapy.

METHODS

Quantitative CT analysis by an independent radiology laboratory and a qualitative evaluation by five blinded experts of the baseline thoracic CT imaging were performed. Univariate and multivariate logistic regression analyses were performed to elucidate characteristics associated with clinical response.

RESULTS

In total, 125 patients underwent coil treatment and had evaluable 12-month follow-up results. Of these, 78 patients received treatment of lobes with the highest emphysematous destruction determined by quantitative CT analysis (quantitative visual match [QVM]+), and 47 received treatment in at least one lobe that was not the most destroyed (QVM-). From the 78 patients with QVM+ treatment, a subgroup of 50 patients (64%) was identified with baseline residual volume > 200% predicted, emphysema score > 20% low attenuation area, and absence of airway disease. In this subgroup, greater lobar residual volume reduction in the treated lobes was achieved, which was associated with significant mean ± SE improvement in FEV₁ (15.2 ± 3.1%), St. George's Respiratory Questionnaire (-12 ± 2 points), and residual volume (-0.57 ± 0.13 L).

DISCUSSION

This post hoc analysis found that both significant hyperinflation (residual volume ≥ 200% predicted) and CT analysis are critical for patient selection and treatment planning for endobronchial coil therapy. Quantitative CT analysis is important to identify optimal lobar treatment and to exclude patients with insufficient emphysema (< 20% low attenuation area), whereas visual assessment identifies patients with signs of airway disease associated with worse outcomes.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01608490; URL: www.clinicaltrials.gov.

Emphysema and lung volume reduction: the role of radiology

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death worldwide. One of the main findings is pulmonary emphysema in association with chronic bronchitis. Clinical signs, pulmonary function tests and imaging are the current used methods to diagnose and stage emphysema. Lung volume reduction (LVR) and endoscopic lung volume reduction (ELVR) are the current therapeutic options beside lung transplantation in cases of severe emphysema. Nowadays imaging is one of the key factors for the success of these therapies. Especially quantitative computed tomography (CT) with its increasing possibilities has become a viable tool, providing detailed information about distribution and heterogeneity of emphysema. Other imaging techniques like dual-energy CT (DECT) and functional magnetic resonance (MR) have shown to add functional information. These structural and functional information support thoracic surgeons and interventional pulmonologists in selecting patients and optimizing LVR procedures but also enables the development of new endobronchial therapies. Imaging will further improve the individual outcome by supporting the choice of optimal therapy.

Valve therapy in patients with emphysematous type of chronic obstructive pulmonary disease (COPD): from randomized trials to patient selection in clinical practice

In recent years a number of endoscopic methods have emerged to treat patients with severe emphysematous type of chronic obstructive pulmonary disease (COPD), who are primarily symptomatic due to hyperinflation despite optimal medical management. Of these techniques, implantation of endobronchial one-way valves into targeted airways of isolated emphysematous lobes appears to be one of the most promising innovations. Results from randomized controlled trials of valve therapy for emphysema show consistent benefits in terms of lung function, exercise capacity, symptoms, and quality of life. This review aims to provide a comprehensive summary of the currently available scientific data, discussion of typical treatment related side effects, and recommendations for patient selection in clinical practice.

Pleural Adhesion Assessment as a Predictor for Pneumothorax after Endobronchial Valve Treatment

BACKGROUND

Pneumothorax after bronchoscopic lung volume reduction using one-way endobronchial valves (EBVs) in patients with advanced emphysema occurs in approximately 20% of patients. It is not well known which factors predict the development of pneumothorax.

OBJECTIVE

To assess whether pleural adhesions on pretreatment high-resolution computed tomography (HRCT) scans are associated with pneumothorax occurrence after EBV treatment.

METHODS

HRCT scan analyses were performed on all patients who received EBV treatment in a randomized controlled trial. Three blinded readers scored adhesions by number and by measuring the longest axis of each pleural adhesion in the treated lung. The Pleural Adhesion Score (PAS) was calculated by adding 1 point for each small pleural lesion (<1 mm), 5 points for each medium-sized lesion (1-5 mm), and 10 points for each large lesion (>5 mm).

RESULTS

The HRCT scans of 64 treated patients were assessed, of whom 14 developed pneumothorax. Patients who developed pneumothorax had a higher median number of pleural adhesions, 2.7 (IQR 1.9-4) compared to 1.7 (1-2.7) adhesions in the group without pneumothorax (p < 0.01). The PAS in the group with pneumothorax was higher compared to that in the group without: 14.3 (12.4-24.1) versus 6.7 (3.7-11.2) (p < 0.01). A threshold PAS of ≥12 was associated with a higher risk of pneumothorax (OR 13.0, 95% CI 3.1-54.9). A score <12 did not rule out the occurrence of pneumothorax.

CONCLUSION

A higher number of pleural adhesions on HRCT with a subsequent higher PAS in the treated lung is associated with a higher occurrence of pneumothorax after EBV treatment.

Coil therapy for patients with severe emphysema and bilateral incomplete fissures - effectiveness and complications after 1-year follow-up: a single-center experience

Background

Lung volume reduction coil (LVRC) treatment is established in daily endoscopic lung volume reduction routine. The aim of this study was to evaluate the safety and efficacy of LVRC treatment.

Patients and methods

This was a retrospective analysis of 86 patients (male/female: 40/46, mean age: 64±7 years) with severe COPD and bilateral incomplete fissures. A total of 10 coils were unilaterally implanted in a single lobe, and 28 out of 86 patients were treated bilaterally. At 90-, 180-, and 365-day follow-up, changes in pulmonary function test (PFT), 6-minute walk test (6MWT) and modified Medical Research Council (mMRC) dyspnea scale, as well as possible complications, were recorded.

Results

At 90 days, the forced expiratory volume in 1 second did improve (P<0.001), but the improvement was not sustained at the 180- and 365-day follow-up (baseline: 0.71±0.21 vs 0.77±0.23 vs 0.73±0.22 vs 0.70±0.18 L). Both vital capacity and residual volume improved significantly (P<0.001) at the 90- and 180-day follow-up, but the improvement was lost after 365 days. Total lung capacity decreased at the 90-day follow-up but returned to baseline values at the 180- and 365-day follow-up. 6MWT (P=0.01) and mMRC (P=0.007) also improved at 90 and 180 days (Δ6MWT of 31±54 and 20±60 m, respectively), but the improvement was also lost at the 365-day follow-up. No significant further improvement was evident at any point in the follow-up after the second procedure. A total of 4 out of 86 patients passed away due to complications. Significant complications in the first 3 months and then at 12 months included the following: severe hemoptysis in 4 (3.5%) and 4 (3.5%) patients, pneumonia requiring hospitalization in 32 (28.1%) and 9 (7.9%) patients and pneumothorax in 7 (6.1%) and 2 (1.7%) patients, respectively. Milder adverse events included self-limited hemoptysis, pneumonias, or COPD exacerbations treated orally.

Conclusion

LVRC improved PFT, 6MWT and mMRC initially, but the improvement was lost after 365 days. Furthermore, we observed 4 deaths and significant severe complications, which need to be further elucidated.

Status of and prospects for bronchoscopic lung volume reduction for patients with severe emphysema

Bronchoscopic lung volume reduction (BLVR) is a minimally invasive treatment for severe emphysema, providing treatment options for patients who are unable to undergo lung volume reduction surgery (LVRS) or lung transplantation. Current BLVR techniques include bronchoscopic volume reduction with valve implants, use of a lung volume reduction coil (LVRC), bronchoscopic thermal vapor ablation (BTVA), biological lung volume reduction (BioLVR), and use of airway bypass stents (ABS). To date, several randomized controlled trials of these bronchoscopic therapies have been conducted in patients with emphysema, and bronchoscopic volume reduction with valve implants remains the best approach thus far. Recent studies indicate that BLVR may be of great value in improving lung function, exercise capacity, and quality of life and that BLVR has the potential to replace conventional surgery for patients with severe emphysema. Optimal patient selection and the proper selection of the BLVR technique in accordance with patient characteristics are crucial to the success of BLVR. More multicenter, prospective, randomized controlled trials need to be conducted in the future to optimize the current selection strategy and evaluate the safety, efficiency, and long-term benefit of BLVR techniques.

Lung volume reduction of pulmonary emphysema: the radiologist task

PURPOSE OF REVIEW

Several lung volume reduction (LVR) techniques have been increasingly evaluated in patients with advanced pulmonary emphysema, especially in the last decade. Radiologist plays a pivotal role in the characterization of parenchymal damage and, thus, assessment of eligibility criteria. This review aims to discuss the most common LVR techniques, namely LVR surgery, endobronchial valves, and coils LVR, with emphasis on the role of computed tomography (CT).

RECENT FINDINGS

Several trials have recently highlighted the importance of regional quantification of emphysema by computerized CT-based segmentation of hyperlucent parenchyma, which is strongly recommended for candidates to any LVR treatment. In particular, emphysema distribution pattern and fissures integrity are evaluated to tailor the choice of the most appropriate LVR technique. Furthermore, a number of CT measures have been tested for the personalization of treatment, according to imaging detected heterogeneity of parenchymal disease.

SUMMARY

CT characterization of heterogeneous parenchymal abnormalities provides criteria for selection of the preferable treatment in each patient and improves outcome of LVR as reflected by better quality of life, higher exercise tolerance, and lower mortality.

The fissure: interlobar collateral ventilation and implications for endoscopic therapy in emphysema

In patients with severe emphysema, bronchoscopic lung volume reduction using one-way valves is a promising therapeutic option to improve lung function and quality of life. The goal of this treatment is to achieve a complete lobar atelectasis. In a significant proportion of patients, this atelectasis cannot be achieved due to interlobar collateral ventilation. This collateral ventilation is generated through incomplete lobar fissures. Therefore, only patients with complete fissures and no collateral ventilation can be selected for endobronchial therapy with one-way valves.

Incomplete fissures are very common and exhibit a great variation in anatomy. The reported prevalence is 17%–85% for the right major fissure, 19%–74% for the left major fissure, and 20%–90% for the minor fissure. There are several methods of measuring or predicting the presence of collateral ventilation, with computed tomography (CT)-fissure analysis and the Chartis measurement being the most important. CT-fissure analysis is an indirect method to measure the completeness of fissures as a surrogate for collateral ventilation. The Chartis system is an endobronchial method to directly measure the presence of collateral ventilation. Both methods have unique value, and the combination of both can accurately predict the treatment response to the bronchoscopic placement of endobronchial valves. This review provides an in-depth view of lung fissure and collateral ventilation to help understand its importance in selecting the appropriate patients for new emphysema treatments and thus avoid useless treatment in unsuitable patients.

Emphysema prevalence related air pollution caused by a cement plant

Background

To identify adverse pulmonary health effects due to air pollution derived from a cement plant in Korea. The emphysema prevalence in residents around a cement plant was compared to that in the group who live far away from the plant by chest films (PA and lateral view) and high-resolution computed tomography (HRCT) lung images.

Methods

From June to August in 2013 and from August to November in 2014, chest films and HRCT scan were conducted on residents over the age of 40 who lived around a cement plant. The residents were divided into two groups; a “more exposed group (MEG)” which consisted of 1,046 people who lived within a 1 km radius and a “less exposed group (LEG)” which consisted of 317 people who lived more than 5 km away from the same plant. We compared the emphysema prevalence and estimated the OR of this between the MEG and the LEG by using a chi-square and logistic regression on chest films and HRCT.

Results

The emphysema prevalence was 9.1 % in the LEG, 14.3 % in the MEG on chest films and 11.4 %, 17.8 % on the HRCT, respectively. The OR of the emphysema prevalence in MEG was 2.92 (95 % CI 1.77-4.83) on the chest films, 2.56 (95 % CI 1.64–3.99) on the HRCT after sex, age, body mass index (BMI), smoking history, residency period and firewood used history were adjusted. The OR in the less than 29 pack-years smoking history was 1.66 (95 % CI 0.92–3.06) and in the more than 30 pack-years was 3.05 (95 % CI 1.68–5.52) on the chest films, and was 1.68 (95 % CI 0.98–2.90), 2.93 (95 % CI 1.72–4.98) on the HRCT, respectively.

Conclusion

The emphysema prevalence seems to be affected by the level of exposure to air pollution derived from the cement plant as well as sex, age, BMI, and smoking history in this study. Moreover, the OR of the case of the more exposed to the air pollution was similar to that of the case in smoking.

Clinical review: Endobronchial valve treatment for emphysema

Breathlessness and impaired quality of life are prominent features in patients with severe emphysema even when conventional methods of treatment are optimal. Lung volume reduction using endobronchial management for emphysema has emerged as a new method to relieve symptoms and improve lung function tests in this group. The endobronchial valves (EBVs) are the most widely used treatment. This article outlines current criteria of patients' selection with literature review and evidence of efficacy. Complications of EBV insertion as well as current shortfalls of this method of treatment are also discussed.

Outcomes of Endobronchial Valve Treatment Based on the Precise Criteria of an Endobronchial Catheter for Detection of Collateral Ventilation under Spontaneous Breathing

BACKGROUND

Endoscopic lung volume reduction with valves is a valid therapeutic option for COPD patients with severe emphysema. The exclusion of interlobar collateral ventilation (CV) is an important predictor of clinical success.

OBJECTIVES

Recently, a catheter-based endobronchial in vivo measurement system (Chartis, Pulmonx, USA) has become routine in the clinical evaluation of CV status in target lobes, but the criteria for phenotyping CV by Chartis evaluation have not yet been defined. We asked the questions, how many phenotypes can be identified using Chartis, what are the exact criteria to distinguish them, and how do the Chartis phenotypes respond to valve insertion?

METHODS

In a retrospective study, 406 Chartis assessments of 166 patients with severe COPD were analyzed. Four Chartis phenotypes, CV positive (CV+), CV negative (CV-), low flow (LF) and low plateau were identified. Fifty-two patients without CV were treated with valves and followed for 3 months.

RESULTS

The Chartis phenotypes were discriminated with respect to decline in expiratory peak flow, increase in resistance index and change in total exhaled volume after 1, 2, 3, 4 and 5 min of measurement time (p < 0.0001, ANOVA), and the cutoff criteria were defined accordingly. To examine the application of these phenotyping criteria, students applied them to 100 Chartis assessments, and they demonstrated almost perfect inter- and intraobserver agreements (x03BA; > 0.9). Compared to baseline, CV- and LF patients with ipsilateral CV- lobe showed an improvement in FEV1 (p < 0.05), vital capacity (p < 0.05) and target lobe volume reduction (p < 0.005) after valve insertion.

CONCLUSION

This study describes the most prevalent Chartis phenotypes.

Endobronchial Valves for Emphysema without Interlobar Collateral Ventilation

BACKGROUND

Bronchoscopic lung-volume reduction with the use of one-way endobronchial valves is a potential treatment for patients with severe emphysema. To date, the benefits have been modest but have been hypothesized to be much larger in patients without interlobar collateral ventilation than in those with collateral ventilation.

METHODS

We randomly assigned patients with severe emphysema and a confirmed absence of collateral ventilation to bronchoscopic endobronchial-valve treatment (EBV group) or to continued standard medical care (control group). Primary outcomes were changes from baseline to 6 months in forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and 6-minute walk distance.

RESULTS

Eighty-four patients were recruited, of whom 16 were excluded because they had collateral ventilation (13 patients) or because lobar segments were inaccessible to the endobronchial valves (3 patients). The remaining 68 patients (mean [±SD] age, 59±9 years; 46 were women) were randomly assigned to the EBV group (34 patients) or the control group (34). At baseline, the FEV1 and FVC were 29±7% and 77±18% of the predicted values, respectively, and the 6-minute walk distance was 374±86 m. Intention-to-treat analyses showed significantly greater improvements in the EBV group than in the control group from baseline to 6 months: the increase in FEV1 was greater in the EBV group than in the control group by 140 ml (95% confidence interval [CI], 55 to 225), the increase in FVC was greater by 347 ml (95% CI, 107 to 588), and the increase in the 6-minute walk distance was greater by 74 m (95% CI, 47 to 100) (P<0.01 for all comparisons). By 6 months, 23 serious adverse events had been reported in the EBV group, as compared with 5 in the control group (P<0.001). One patient in the EBV group died. Serious treatment-related adverse events in this group included pneumothorax (18% of patients) and events requiring valve replacement (12%) or removal (15%).

CONCLUSIONS

Endobronchial-valve treatment significantly improved pulmonary function and exercise capacity in patients with severe emphysema characterized by an absence of interlobar collateral ventilation. (Funded by the Netherlands Organization for Health Research and Development and the University Medical Center Groningen; Netherlands Trial Register number, NTR2876.).

Endoscopic bronchial valve treatment: patient selection and special considerations

As well as lung volume reduction surgery, different minimally invasive endoscopic techniques are available to achieve lung volume reduction in patients with severe emphysema and significant hyperinflation. Lung function parameters and comorbidities of the patient, as well as the extent and distribution of the emphysema are factors to be considered when choosing the patient and the intervention. Endoscopic bronchial valve placement with complete occlusion of one lobe in patients with heterogeneous emphysema is the preferred technique because of its reversibility. The presence of high interlobar collateral ventilation will hinder successful treatment; therefore, endoscopic coil placement, polymeric lung volume reduction, or bronchoscopic thermal vapor ablation as well as lung volume reduction surgery can be used for treating patients with incomplete fissures. The effect of endoscopic lung volume reduction in patients with a homogeneous distribution of emphysema is still unclear and this subgroup should be treated only in clinical trials. Precise patient selection is necessary for interventions and to improve the outcome and reduce the risk and possible complications. Therefore, the patients should be discussed in a multidisciplinary approach prior to determining the most appropriate treatment for lung volume reduction.

Endoscopic volume reduction in COPD- a critical review

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is common in Germany, with a prevalence of 13.2%. The available treatments are exclusively symptomatic, except for lung transplantation, from which no more than a few patients can benefit. Over the past decade, endoscopic lung volume reduction (ELVR) has broadened the therapeutic spectrum for patients with advanced pulmonary emphysema.

METHODS

We review pertinent publications that were retrieved from Pubmed using the search terms "endoscopic lung volume reduction," "endobronchial valves," "endobronchial coil," and "bronchoscopic thermal vapor ablation," along with current data from the annual meeting of the German Respiratory Society (Deutsche Gesellschaft für Pneumologie).

RESULTS

ELVR is now performed with three different techniques. Endoscopic valve implantation has been studied in three randomized controlled trials (RCTs) and several noncontrolled trials, which have shown a benefit from valve therapy particularly for patients who have only a small amount of interlobar collateral ventilation or none at all. A reduction of lobar lung volume by 56-80% was found, in association with a significant improvement of lung function (a 16-26% increase of forced expiratory volume in one second [FEV1]). The main complication of valve therapy is pneumothorax, which arises in up to 23% of cases. Coil implantation has been studied to date in only a single RCT, which revealed a significant improvement in quality of life as the primary endpoint (St. George´s Respiratory Questionnaire [SGRQ]: -8 points). Bronchoscopic thermoablation has been studied only in noncontrolled intervention trials; in patients with emphysema mainly affecting the upper lobes, it has been found to reduce lobar volume by an average of 48%.

CONCLUSION

Endoscopic lung volume reduction has broadened the therapeutic spectrum for selected patients with advanced pulmonary emphysema. Further prospective trials are needed to evaluate the benefits, risks, and long-term effects of the available techniques for ELVR.

An update on the efficacy of endobronchial valve therapy in the management of hyperinflation in patients with chronic obstructive pulmonary disease

Lung volume reduction surgery has been shown to be effective in patients with heterogeneous emphysema, but is also associated with a relatively high perioperative morbidity and mortality. Accordingly, several novel and potentially less invasive methods for bronchoscopic lung volume reduction have been developed. Endobronchial valve (EBV) therapy is one such therapeutic approach in patients with advanced emphysema. It has been the most widely studied technique over the past years and represents an effective treatment option for patients with severe heterogeneous upper- or lower-lobe-predominant emphysema. The choice of EBV therapy largely depends on the distribution of emphysema and the presence or absence of interlobar collateral ventilation. Adequate patient selection and technical success of valve implantation with the intention of lobar exclusion are predictive factors for positive outcomes. This review attempts to highlight the milestones in the development of bronchoscopic lung volume reduction with one-way valve implantation over the past few years.

Radiologic manifestations of bronchoscopic lung volume reduction in severe chronic obstructive pulmonary disease

OBJECTIVE. Bronchoscopic lung volume reduction promises to become an effective treatment option in severe chronic obstructive pulmonary disease. Several techniques are currently being investigated, including implantation of devices into the lung and instillation of hot water vapor or polymer. This article reviews the spectrum of radiologic manifestations on chest radiography and CT that occur after the intervention. CONCLUSION. Familiarity with the intended effects and adverse events will aid the radiologist in supporting bronchoscopic lung volume reduction.

Endoscopic lung volume reduction with endobronchial valves in patients with severe emphysema and established pulmonary hypertension

BACKGROUND

One of the most common forms of pulmonary hypertension (PH) is that associated with chronic obstructive pulmonary disease (COPD). So far, patients with severe emphysema and established PH have been excluded from endoscopic lung volume reduction (ELVR) therapy due to the risk of right heart decompensation.

OBJECTIVE

The aim of this pilot study was to evaluate the feasibility and efficacy of ELVR using one-way endobronchial valves (EBV) in this specific group of patients.

METHODS

We prospectively included 6 patients with COPD, severe heterogeneous emphysema, and established PH who underwent right heart catheterization and clinical assessments before and 90 days after ELVR with unilateral EBV placement.

RESULTS

This study was not powered to measure any statistical differences in endpoints. Ninety days after ELVR, the symptoms, lung function, and hemodynamics improved in 5 out of 6 patients (1 patient normalized and 1 slightly worsened). The mean hemodynamics improved from baseline to 90 days after ELVR as follows: mean pulmonary artery pressure, -2.5 ± 3.5 mm Hg; pulmonary arterial wedge pressure, -4.3 ± 8.3 mm Hg; cardiac index, +0.3 ± 0.6 l/min/m(2), and 6-min walk distance, +59 ± 99 m. ELVR was performed without PH-related complications in all patients.

CONCLUSION

To our knowledge, this is the first prospective, single-center pilot study to evaluate the feasibility and efficacy of ELVR in patients with established PH. ELVR was feasible and resulted in an improvement of clinical and hemodynamic parameters in 5 out of 6 patients. These results have to be further confirmed in larger-scale controlled studies.

Predictors of efficacy for endobronchial valves in bronchoscopic lung volume reduction: A meta-analysis

Over the last several years, numerous trials have been carried out to check the efficacy of one-way valves in the management of advanced emphysema. While the design of the valves has not altered much, by selectively studying these valves in a select group of participants, such as those with and without intact fissures (FI+ and FI-), and by using different procedural techniques, our understanding of the valves has evolved. In this meta-analysis, we sought to study the effect of these factors on the efficacy of one-way valves. From PubMed and Embase, we included only those studies that provided separate data on fissure integrity or collateral ventilation. Our study outcomes included the mean change in forced expiratory volume in first second (FEV1), 6-minute walk distance (6MWD) and the St George's Respiratory Questionnaire (SGRQ). In the FI+ subgroup of participants, the pooled standardized mean difference in FEV1, 6MWD, and SGRQ were 0.50 (95% confidence interval (CI): 0.34 to 0.67), p ≤ 0.001, 0.29 (95% CI: 0.13 to 0.45), p ≤ 0.001 and -6.02 (95% CI: -12.12 to 0.06), p = 0.05, respectively. In comparison, these results were superior to the FI- subgroup of participants. A separate analysis of the FI+ subgroup based on lobar occlusion versus nonlobar occlusion favored the former for superior efficacy. The preliminary findings of our meta-analysis confirm that one-way valves perform better in a select group of patients who show intact fissures on lung imaging pretreatment and in those who achieve lobar occlusion.

Bronchoscopic interventions for chronic obstructive pulmonary disease

Over the past decade, several non-surgical and minimally invasive bronchoscopic lung volume reduction (BLVR) techniques have been developed to treat patients with severe chronic obstructive pulmonary disease (COPD). BLVR can be significantly efficacious, suitable for a broad cohort of patients, and associated with a solid safety profile at a reasonable expense. The introduction of BLVR is also expected to accelerate the further development of interventional pulmonology worldwide. Recently, results from clinical studies on BLVR techniques have been published, providing valuable information about the procedure's indications, contraindications, patient-selection criterion and outcomes. BLVR utilizing one-way endobronchial valves is gaining momentum as an accepted treatment in regular medical practice because of the identification of best responders. Patients with a heterogeneous emphysema distribution and without inter-lobar collateral ventilation show encouraging results. Furthermore, for patients with collateral ventilation, who are not considered candidates for valve treatment, and for patients with homogeneous emphysema, the introduction of lung volume reduction coil treatment is a promising solution. Moreover, with the development of newer treatment modalities, that is, biochemical sealant and thermal water vapor, the potential to treat emphysema irrespective of collateral flow, may be further increased. Nevertheless, patient selection for BLVR treatment will be crucial for the procedure's success and should be performed using a multidisciplinary team approach. Consequently, BLVR needs to be concentrated in high-volume centres that will offer better quality and experience with treatment challenges and adverse events. This review gives a general overview of BLVR from an expert and scientific perspective.

Effectiveness of endobronchial coil treatment for lung volume reduction in patients with severe heterogeneous emphysema and bilateral incomplete fissures: a six-month follow-up

BACKGROUND

Treatment with lung volume reduction coils (LVRC) may be effective in patients with severe heterogeneous emphysema and incomplete fissures.

OBJECTIVE

We hypothesized that LVRC placement improves pulmonary function, exercise tolerance and quality of life in these patients.

METHODS

Twenty-six patients with chronic obstructive pulmonary disease (COPD), 13 males and 13 females, aged 66 ± 8 years with heterogeneous emphysema and incomplete fissures were included in this retrospective analysis. The coils were implanted unilaterally in the upper or lower lobe. Patients were followed up at 30, 90 and 180 days after treatment and changes in pulmonary function test and 6-minute-walk-test (6MWT) values as well as scores for the modified Medical Research Council (mMRC) dyspnea scale and the St. George's Respiratory Questionnaire (SGRQ) were recorded.

RESULTS

FEV1 improved significantly at 90 days and tended to decrease at the 180-day follow-up (0.67 ± 0.17 vs. 0.78 ± 0.25 vs. 0.73 ± 0.21 liters, respectively, p < 0.001). The 6MWT score had improved significantly at 90 days and had tended to decrease at the 180-day follow-up (216 ± 107 vs. 262 ± 97 vs. 262 ± 112 m, respectively, p = 0.001). SGRQ was significantly improved at 90 days. Multivariate analysis showed that worse 6MWT performance at baseline was independently associated with a greater improvement in 6MWT at the 90-day follow-up. The total complication rate was 54% (n = 14) and included light hemorrhage in 6 patients, COPD exacerbation in 6, pneumothorax in 1 and both COPD exacerbation and pneumothorax in 1 patient.

CONCLUSIONS

This is the first study to show that LVRC in patients with heterogeneous emphysema and incomplete fissures improves exercise capacity, quality of life and lung function up to 90 days after the intervention. Further studies are needed to assess the long-term effects of LVRC in these patients.

Incomplete pulmonary fissures evaluated by volumetric thin-section CT: semi-quantitative evaluation for small fissure gaps identification, description of prevalence and severity of fissural defects

OBJECTIVE

To assess the interobserver agreement for a semi-quantitative evaluation of the interlobar fissures integrity in volumetric thin-section CT images, looking for more detailed information regarding fissural defects; and describe prevalence and severity of fissural defects between the different functional groups of subjects.

MATERIALS AND METHODS

Volumetric scans of 247 individuals exposed to tobacco with different functional status (normal to severe COPD), were retrospectively and independently evaluated by 2 chest radiologists, with a consensual reading additionally with a third reader in disagreement cases. Right oblique (RO), right horizontal (RH) and left oblique fissures (LO) integrity was estimated using a 5% scale. GOLD classification was available for all subjects.

RESULTS

Interobserver agreement (weighted Kappa-index) for fissural categorization was 0.76, 0.70 and 0.75, for RO, RH and LO, respectively. Final evaluation found 81%, 89% and 50% of RO, RH and LO to be incomplete, with respective mean integrity of 80%, 58% and 80%. Small fissure gaps (<10%) were present in 30% of patients. Prevalence and severity of fissural defects were not different between the GOLD categories.

CONCLUSIONS

A substantial agreement between readers was found in the analysis of interlobar fissures integrity. The semi-quantitative method allowed a detailed description of the fissural defects, information that can be important, for example, in endoscopic lung volume reduction therapies for emphysema. Small fissure gaps, overlooked in previous studies, were found in almost a third of the patients. A higher than previously described prevalence of fissural defects was described, but without significant differences among the distinct functional groups.

Endobronchial valves in severe emphysematous patients: CT evaluation of lung fissures completeness, treatment radiological response and quantitative emphysema analysis

OBJECTIVE: To evaluate lung fissures completeness, post-treatment radiological response and quantitative CT analysis (QCTA) in a population of severe emphysematous patients submitted to endobronchial valves (EBV) implantation. MATERIALS AND METHODS: Multi-detectors CT exams of 29 patients were studied, using thin-section low dose protocol without contrast. Two radiologists retrospectively reviewed all images in consensus; fissures completeness was estimated in 5% increments and post-EBV radiological response (target lobe atelectasis/volume loss) was evaluated. QCTA was performed in pre and post-treatment scans using a fully automated software. RESULTS: CT response was present in 16/29 patients. In the negative CT response group, all 13 patients presented incomplete fissures, and mean oblique fissures completeness was 72.8%, against 88.3% in the other group. QCTA most significant results showed a reduced post-treatment total lung volume (LV) (mean 542 ml), reduced EBV-submitted LV (700 ml) and reduced emphysema volume (331.4 ml) in the positive response group, which also showed improved functional tests. CONCLUSION: EBV benefit is most likely in patients who have complete interlobar fissures and develop lobar atelectasis. In patients with no radiological response we observed a higher prevalence of incomplete fissures and a greater degree of incompleteness. The fully automated QCTA detected the post-treatment alterations, especially in the treated lung analysis.