Prognostic value of a composite physiologic index developed by adding bronchial and hyperlucent volumes quantified via artificial intelligence technology.

Background: The composite physiologic index (CPI) was developed to estimate the extent of interstitial lung disease (ILD) in idiopathic pulmonary fibrosis (IPF) patients based on pulmonary function tests (PFTs). The CALIPER-revised version of the CPI (CALIPER-CPI) was also developed to estimate the volume fraction of ILD measured by CALIPER, an automated quantitative CT postprocessing software. Recently, artificial intelligence-based quantitative CT image analysis software (AIQCT), which can be used to quantify the bronchial volume separately from the ILD volume, was developed and validated in IPF.

Refractory phenotype of -sensitized asthma with bronchiectasis and allergic bronchopulmonary aspergillosis.

Background: Sensitization to mucus plugs, and bacterial colonization may coexist and relate to a refractory phenotype during follow-up in asthma with bronchiectasis and allergic bronchopulmonary aspergillosis (ABPA).

Objective: This study aimed to clarify the features of -sensitized refractory asthma with bronchiectasis and determine the refractory phenotype in this population and ABPA.

Methods: This study included cases of the oldest available -specific IgE data and chest computed tomography images from a nationwide survey of refractory asthma with bronchiectasis.

Computed tomography morphological assessments of central airways in interstitial lung abnormalities and idiopathic pulmonary fibrosis.

Background: Little is known about whether central airway morphological changes beyond traction bronchiectasis develop and affect clinical outcomes in patients with idiopathic pulmonary fibrosis (IPF). This study aimed to compare central airway structure comprehensively between patients with IPF, subjects with interstitial lung abnormality (ILA), and those without ILA (control) using computed tomography (CT). We further examined the prognostic impact of IPF-specific CT airway parameters in patients with IPF.

Lung imaging in COPD and asthma.

Chronic obstructive pulmonary disease (COPD) and asthma are common lung diseases with heterogeneous clinical presentations. Lung imaging allows evaluations of underlying pathophysiological changes and provides additional personalized approaches for disease management. This narrative review provides an overview of recent advances in chest imaging analysis using various modalities, such as computed tomography (CT), dynamic chest radiography, and magnetic resonance imaging (MRI).

Lower skeletal muscle density and airway structure on computed tomography in asthma.

Background: Lower skeletal muscle density may reflect muscle adiposity and metabolic dysregulation that potentially impair disease control and lung function independent of high body mass index (BMI) in patients with asthma.

Objective: To investigate whether the lower density of pectoralis muscles (PMs) and erector spinae muscles (ESMs) on chest computed tomography was associated with airway structural changes in patients with asthma.

Methods: Consecutive patients with asthma and healthy controls undergoing chest computed tomography were retrospectively analyzed.

Phase angle measured by bioelectrical impedance analysis in patients with chronic obstructive pulmonary disease: Associations with physical inactivity and frailty.

Background: Factors associated with early-stage frailty (pre-frailty) in patients with chronic obstructive pulmonary disease (COPD) remain unestablished. In addition to skeletal muscle quantity, skeletal muscle dysfunction can be estimated using an angular metric from bioelectrical impedance analyzer (BIA), termed the phase angle, that reflects cell membrane reactance representing the structural stability. This study examined whether the phase angle was more closely associated with pre-frailty compared with skeletal muscle quantity in patients with COPD.

Longitudinal assessment of interstitial lung abnormalities on CT in patients with COPD using artificial intelligence-based segmentation: a prospective observational study.

Background: Interstitial lung abnormalities (ILAs) on CT may affect the clinical outcomes in patients with chronic obstructive pulmonary disease (COPD), but their quantification remains unestablished. This study examined whether artificial intelligence (AI)-based segmentation could be applied to identify ILAs using two COPD cohorts.

Methods: ILAs were diagnosed visually based on the Fleischner Society definition.

Investigation of predictors for in-hospital death or long-term hospitalization in community-acquired pneumonia with risk factors for aspiration.

Background: It is known that the mortality of pneumonia in patients with risk factors for aspiration is worse than that in those without these risk factors. However, it is still unknown which risk factors for aspiration predict prognosis. Therefore, we aimed to determine which risk factors for aspiration are associated with death or prolonged hospitalization.

Quantification of Airway Structures by Persistent Homology.

We propose two types of novel morphological metrics for quantifying the geometry of tubular structures on computed tomography (CT) images. We apply our metrics to identify irregularities in the airway of patients with chronic obstructive pulmonary disease (COPD) and demonstrate that they provide complementary information to the conventional metrics used to assess COPD, such as the tissue density distribution in lung parenchyma and the wall area ratio of the segmented airway. The three-dimensional shape of the airway and its abstraction as a rooted tree with the root at the trachea carina are automatically extracted from a lung CT volume, and the two metrics are computed based on a mathematical tool called persistent homology; treeH0 quantifies the distribution of branch lengths to assess the complexity of the tree-like structure and radialH0 quantifies the irregularities in the luminal radius along the airway.

Centrilobular emphysema and airway dysanapsis: factors associated with low respiratory function in younger smokers.

Background: Low respiratory function in young adulthood is one of the important factors in the trajectory leading to the future development of COPD, but its morphological characteristics are not well characterised.

Methods: We retrospectively enrolled 172 subjects aged 40-49 years with ≥10 pack-years smoking history who underwent lung cancer screening by computed tomography (CT) and spirometry at two Japanese hospitals. Emphysema was visually assessed according to the Fleischner Society guidelines and classified into two types: centrilobular emphysema (CLE) and paraseptal emphysema (PSE).

Associations of fractional exhaled nitric oxide with airway dimension and mucus plugs on ultra-high-resolution computed tomography in former smokers and nonsmokers with asthma.

Background: Associations of fractional exhaled nitric oxide (FeNO) with airway wall remodeling and mucus plugs remain to be explored in smokers and nonsmokers with asthma. Ultra-high-resolution computed tomography (U-HRCT), which allows accurate structural quantification of airways >1 mm in diameter, was used in this study to examine whether higher FeNO was associated with thicker walls of the 3rd to 6th generation airways and mucus plugging in patients with asthma.

Methods: The retrospective analyses included consecutive former smokers and nonsmokers with asthma who underwent U-HRCT in a hospital.

Longitudinal changes in respiratory reactance in patients with COPD: associations with longitudinal change in air-trapping, exacerbations, and mortality.

Introduction: Air-trapping affects clinical outcomes in patients with chronic obstructive pulmonary disease (COPD) and may be detected by reactance at 5 Hz (X5) on respiratory oscillometry because X5 sensitively reflects the elasticity of the chest wall, airway and lung. However, the longitudinal association between X5 and air-trapping remains to be explored. This study aimed to test whether longitudinal changes in X5 could be associated with air-trapping progression, exacerbations, and mortality in patients with COPD.

Aggregated eosinophils and neutrophils characterize the properties of mucus in chronic rhinosinusitis.

Background: Airway obstruction caused by viscous mucus is an important pathophysiologic characteristic of persistent inflammation, which can result in organ damage.

Objective: We investigated the hypothesis that the biophysical characteristics of accumulating granulocytes affect the clinical properties of mucus.

Methods: Surgically acquired nasal mucus samples from patients with eosinophilic chronic rhinosinusitis and neutrophil-dominant, noneosinophilic chronic rhinosinusitis were evaluated in terms of computed tomography density, viscosity, water content, wettability, and protein composition.

A reference equation for lung volume on computed tomography in Japanese middle-aged and elderly adults.

Background: Effective use of lung volume data measured on computed tomography (CT) requires reference values for specific populations. This study examined whether an equation previously generated for multiple ethnic groups in the United States, including Asians predominantly composed of Chinese people, in the Multi-Ethnic Study of Atherosclerosis (MESA) could be used for Japanese people and, if necessary, to optimize this equation. Moreover, the equation was used to characterize patients with chronic obstructive pulmonary disease (COPD) and lung hyperexpansion.

Perioperative changes in radiographic density in erector spinae muscle and mortality after lung transplantation.

Rationale: The radiographic density of the erector spinae muscle (ESM) is often decreased early after lung transplantation (LTx). The prognostic impact of this change has not been elucidated.

Objective: To investigate whether the decrease in the radiographic density of ESMs early after LTx is associated with a poor prognosis.