Low Attenuation Area Research Articles

Quantitative assessment of airway and parenchymal components of chronic obstructive pulmonary disease using thin-section helical computed tomography.

PurposeThe purpose of this study was to diagnose and characterise chronic obstructive pulmonary disease (COPD) into its forms, patterns, and severity using MDCT.Material and methodsIn this prospective study, spirometric and MDCT evaluation was done in 52 consecutive patients diagnosed with COPD. In each patient six segmental bronchi were evaluated for CT morphometric indices of bronchial wall thickness (BWT) and wall area percentage (WAP). Quantitative evaluation of emphysema was done using inbuilt software, and volume of emphysematous lung was determined using percentage low attenuation area (LAA). COPD was categorised into the following: emphysema predominant; airway predominant; or mixed phenotypes, and severity grading was assigned as mild, moderate, or severe.ResultsCentrilobular was the predominant emphysema pattern occurring alone (36.5%) or in combination with paraseptal changes (34.6%). Among COPD phenotypes, emphysema predominant was the commonest (44.3%), followed by mixed (30.8%), and bronchitis predominant (25.0%). The mean BWT in the airway-predominant group was significantly higher (1.94 ± 0.28 mm) than in the emphysema-predominant subgroup (1.79 ± 0.23 mm) with a p value of 0.005.ConclusionMDCT is an indispensable tool in quantitative and qualitative evaluation of COPD patients. Measurement of CT indices like BWT, WAP, and %LAA can reliably categorise COPD into phenotypes like emphysema predominant, airway predominant, or mixed, which serve as a guide for patient management.

Incidence and morphological characteristics of the reversed halo sign in patients with acute pulmonary embolism and pulmonary infarction undergoing computed tomography angiography of the pulmonary arteries.

ABSTRACTObjective:To determine the incidence of the reversed halo sign (RHS) in patients with pulmonary infarction (PI) due to acute pulmonary embolism (PE), detected by computed tomography angiography (CTA) of the pulmonary arteries, and to describe the main morphological features of the RHS. Methods:We evaluated 993 CTA scans, stratified by the risk of PE, performed between January of 2010 and December of 2014. Although PE was detected in 164 scans (16.5%), three of those scans were excluded because of respiratory motion artifacts. Of the remaining 161 scans, 75 (46.6%) showed lesions consistent with PI, totaling 86 lesions. Among those lesions, the RHS was seen in 33 (38.4%, in 29 patients). Results:Among the 29 patients with scans showing lesions characteristic of PI with the RHS, 25 (86.2%) had a single lesion and 4 (13.8%) had two, totaling 33 lesions. In all cases, the RHS was in a subpleural location. To standardize the analysis, all images were interpreted in the axial plane. Among those 33 lesions, the RHS was in the right lower lobe in 17 (51.5%), in the left lower lobe in 10 (30.3%), in the lingula in 5 (15.2%), and in the right upper lobe in 1 (3.0%). Among those same 33 lesions, areas of low attenuation were seen in 29 (87.9%). The RHS was oval in 24 (72.7%) of the cases and round in 9 (27.3%). Pleural effusion was seen in 21 (72.4%) of the 29 patients with PI and the RHS. Conclusions:A diagnosis of PE should be considered when there are findings such as those described here, even in patients with nonspecific clinical symptoms.

Velika plućna cista kod nepušača - sporadičan nalaz

Cystic lung disease (CLD) is a group of lung disorders characterized by the presence of multiple cysts, defined as air-filled lucencies or low-attenuating areas, bordered by a thin wall (usually < 4 mm). It is very often mixed with giant bullaes which are common in patients with emphysema. Case report: A 76-year-old woman with a medical history of subocclusive disturbance was admitted to surgery department. Accidentally, during preoperative examination, chest X-ray revealed giant bullae in the right lung. CT scan confirmed it, but due to the wall thickness the changes have been classified into pulmonary cyst which have a completely different approach in treatment. Thus, patient underwent without surgery and was treated conservatively. Conclusion: The main difference between a giant bullae and a pulmonary cyst is in wall thickness, if it measures between 1 and 4 mm it is pulmonary cyst, unlike bullae whose wall is thinner than 1mm.

The natural history of napkin-ring sign by coronary computed tomography angiography.

IntroductionDespite their significance, the prevalence and the incidence of vulnerable plaques in coronary arteries, as well as their natural history, remain poorly known.AimTo evaluate the prevalence, incidence and evolution of napkin-ring sign (NRS), and to establish factors associated with its presence, progression, or regression, in patients with suspected coronary artery disease (CAD).Material and methodsThe study is based on a single-center prospective registry. Eighty-nine patients with suspected CAD underwent two computed tomography angiography (CTA) examinations within an interval of at least 24 months. High-risk plaque was defined by the presence of a low-attenuation area adjacent to the coronary lumen, surrounded by a ring of higher attenuation – NRS.ResultsAt the baseline 53 NRS were observed in 22 (25%) patients, 7 (8%) patients had single NRS and 15 (17%) had multiple NRS. After the follow-up period, there were 68 NRS in 32 patients. In 18 patients progression was observed with 23 additional NRS. Presence of single NRS and diabetes were independent predictors of NRS progression.ConclusionsThe number of NRS plaque tends to increase over time in patients with suspected CAD. The progression may be predicted by the presence of diabetes or single NRS.

Transthoracic Rebiopsy for Mutation Analysis in Lung Adenocarcinoma: Outcomes and Risk Factors for the Acquisition of Nondiagnostic Specimens in 199 Patients

PurposeTo determine the outcomes of transthoracic rebiopsy for epidermal growth factor receptor (EGFR) mutation in patients with lung adenocarcinoma and to explore the clinical and procedure-related risk factors for the acquisition of nondiagnostic rebiopsy specimens. Patients and MethodsWe retrospectively reviewed 367 patients with lung adenocarcinoma who underwent transthoracic core needle biopsy for mutation analysis from September 2011 to October 2016. Of these, 199 patients underwent rebiopsy. Patient characteristics, treatment history, target lesion characteristics, and procedure-related factors were evaluated. The adequacy rate of specimens for mutation analysis was evaluated. Univariable and multivariable analyses were performed to determine the independent predictors of nondiagnostic specimens. ResultsNinety percent of specimens (179 of 199) were adequate for mutation analysis. The EGFR mutation (exon 18-21) was 65% (117 of 179) and the EGFR T790M mutation 33% (59 of 179) of specimens. In univariable analysis, an internal low-attenuation area in the target lesion (P = .001) and pleural contact (P = .004) on computed tomography were significant risk factors for nondiagnostic specimens. In multivariable analysis, an internal low-attenuation area in the target lesion (odds ratio = 7.333; 95% confidence interval, 1.755-30.633; P = .006) was an independent predictor for acquisition of nondiagnostic specimens. ConclusionImage-guided transthoracic rebiopsy to obtain specimens for mutation analysis in lung adenocarcinoma provides high diagnostic accuracy, with a low rate of nondiagnostic specimens. The presence of internal low-attenuation area in the target lesion on computed tomography was an independent predictor for acquiring nondiagnostic specimens.

Correlation of the modified Medical Research Council dyspnea scale with airway structure assessed by three-dimensional CT in patients with chronic obstructive pulmonary disease.

Dyspnea is a common symptom in chronic obstructive pulmonary disease (COPD). The modified Medical Research Council (mMRC) dyspnea scale is a widely used questionnaire to assess dyspnea. However, the relationship of the mMRC dyspnea scale with morphological airway structures in COPD remains unclear. We evaluated the correlation between the mMRC dyspnea scale and imaging-based airway structures in patients with COPD. The wall area (WA) and airway inner luminal area (Ai) of third-to sixth-generation bronchi and the percentage of low attenuation area with less than -950 HU (%LAA) of the lungs were measured using three-dimensional computed tomography in patients with COPD. WA and Ai were corrected by body surface area (BSA). Forty-two clinically stable patients with COPD were enrolled. The median (range) mMRC dyspnea scale was 2 (0-3). The mMRC dyspnea scale score was significantly correlated with WA/BSA of fifth- and sixth-generation bronchi (Spearman correlation coefficient ρ = 0.386, p = 0.012; ρ = 0.484, p = 0.001, respectively). Partial rank correlation analysis showed that the mMRC dyspnea scale score was significantly correlated with WA/BSA of sixth-generation bronchi, independent of the confounding factors of age, body mass index, %predicted forced expiratory volume in 1 s, %LAA, and Ai/BSA (ρ = 0.481, p = 0.003). However, the %LAA and Ai/BSA were not correlated with this dyspnea scale. Bronchial WA assessed by three-dimensional computed tomography may be used as an assessment tool for dyspnea in patients with COPD.

Emphysema extent on computed tomography is a highly specific index in diagnosing persistent airflow limitation: a real-world study in China

ObjectiveThe diagnostic value of emphysema extent in consistent air flow limitation remains controversial. Therefore, we aimed to assess the value of emphysema extent on computed tomography (CT) on the diagnosis of persistent airflow limitation. Furthermore, we developed a diagnostic criterion for further verification.Materials and methodsWe retrospectively enrolled patients who underwent chest CT and lung function test. To be specific, 671 patients were enrolled in the derivation group (Group 1.1), while 479 patients were in the internal validation group (Group 1.2). The percentage of lung volume occupied by low attenuation areas (LAA%) and the percentile of the histogram of attenuation values were calculated.ResultsIn patients with persistent airflow limitation, the LAA% was higher and the percentile of the histogram of attenuation values was lower, compared with patients without persistent airflow limitation. Using LAA% with a threshold of −950 HU >1.4% as the criterion, the sensitivity was 44.3% and 47.2%, and the specificity was 95.2% and 95.7%, in Group 1.1 and Group 1.2, respectively. The specificity was influenced by the coexistence of interstitial lung disease, pneumothorax, and post-surgery, rather than the coexistence of pneumonia, nodule, or mass. Multivariable models were also developed.ConclusionThe emphysema extent on CT is a highly specific marker in the diagnosis of persistent airflow limitation.

Typing of chronic obstructive pulmonary disease using high-resolution computed tomography and the association with smoking, airway inflammation, and common comorbidities

Background/aim: This study performed typing of chronic obstructive pulmonary disease (COPD) using high-resolution computed tomography (HRCT) to determine the association with smoking, matrix metalloproteinases, and common comorbidities. Materials and methods: The study enrolled 94 hospitalized patients. Participants were divided into a group of 69 current and former smokers (group A) and a group of 25 that had never smoked (group B). Patients were also divided into 3 categories according to the degree of emphysema and bronchial wall thickness using HRCT to determine the association with levels of matrix metalloproteinase 9 (MMP-9) and TIMP-1, as well as associated comorbidities. These three categories were: type A - no or mild emphysema, with or without bronchial wall thickening; type E - emphysema without bronchial wall thickening; and type M - both emphysema and bronchial wall thickening. Results: The low attenuation area (LAA) scores in group A patients were higher than those in group B (t = 2.86, P < 0.01); correlation analysis showed that smoking was associated with a decline of the forced expiratory volume in 1 s and forced vital capacity ratio (FEV1/ FVC%) and higher LAA scores in patients with COPD (F = 4.46, F = 8.20, P < 0.05). The levels of MMP-9 in group A were higher than those in group B (t = 3.65, P < 0.01). Among COPD patients with more than 3 comorbidities, there were statistically significant differences in both the smoking group and the nonsmoking group (chi-square = 12.08, P < 0.01). When compared to type A patients, who had coincident cardiovascular diseases in the smoking group, patients of type M and E showed statistically significant differences (F = 2.42 and 2.12, P < 0.05). Conclusion: Emphysema was more severe in smokers. Metalloproteinase levels in smokers were higher than those in nonsmokers. Moreover, comorbidities were more severe in smokers.

Quantitative computed tomography phenotypes, spirometric parameters, and episodes of exacerbation in heavy smokers: An analysis from South America.

ObjectiveTo evaluate the quantitative computed tomography (QCT) phenotypes, airflow limitations, and exacerbation-like episodes in heavy smokers in Southern Brazil.MethodsWe enrolled 172 smokers with a smoking history ≥30 pack-years who underwent pulmonary function tests (PFTs) and CT scan for lung cancer screening. Patients were classified regarding airflow limitation (FEV1/FVC <0.7 forced expiratory volume in 1 second/forced vital capacity) and the presence of emphysema on the QCT. The QCT were analyzed in specialized software and patients were classified in two disease-predominant phenotypes: emphysema-predominant (EP) and non-emphysema-predominant (NEP). EP was determined as ≥6% of percent low-attenuation areas (LAA%) with less than -950 Hounsfield units. NEP was defined as having a total LAA% of less than 6%.ResultsMost of our patients were classified in the EP phenotype. The EP group had significantly worse predicted FEV1 (60.6 ±22.9 vs. 89.7 ±15.9, p <0.001), higher rates of airflow limitation (85.7% vs. 15%; p <0.001), and had more exacerbation-like episodes (25.8% vs. 8.3%, p <0.001) compared to the NEP group. Smoking history, ethnicity, and BMI did not differ between the groups. The total LAA% was the QCT parameter with the strongest correlation to FEV1 (r = -0.669) and FEV1/FVC (r = -0.787).ConclusionsHeavy smokers with the EP phenotype on QCT were more likely to have airflow limitation, worse predicted FEV1, and a higher rate of exacerbation-like episodes than those with the NEP phenotype. Approximately 23% of patients with no airflow limitation on PFTs were classified in EP phenotype.

CT Imaging-Based Low-Attenuation Super Clusters in Three Dimensions and the Progression of Emphysema

Distributions of low-attenuation areas in two-dimensional (2-D) CT lung slices are used to quantify parenchymal destruction in patients with COPD. However, these segmental approaches are limited and may not reflect the true three-dimensional (3-D) tissue processes that drive emphysematous changes in the lung. The goal of this study was to instead evaluate distributions of 3-D low-attenuation volumes, which we hypothesized would follow a power law distribution and provide a more complete assessment of the mechanisms underlying disease progression. CT scans and pulmonary function test results were acquired from an observational database for N= 12 patients with COPD and N= 12 control patients. The data set included baseline and two annual follow-up evaluations in patients with COPD. Three-dimensional representations of the lungs were reconstructed from 2-D axial CT slices, with low-attenuation volumes identified as contiguous voxels< -960 Hounsfield units. Low-attenuation sizes generally followed a power law distribution, with the exception of large, individual outliers termed "super clusters," which deviated from the expected distribution. Super cluster volume was correlated with disease severity (%total low attenuation, ρ = 0.950) and clinical measures of lung function including FEV1 (ρ= -0.849) and diffusing capacity of the lung for carbon monoxide Dlco (ρ= -0.874). To interpret theseresults, we developed a personalized computational model of super cluster emergence. Simulations indicated disease progression was more likely to occur near existing emphysematous regions, giving rise to a biomechanical, force-induced mechanism of super cluster growth. Low-attenuation super clusters are defining, quantitative features of parenchymal destruction that dominate disease progression, particularly in advanced COPD.

Validation of lung density indices by cardiac CT for quantification of lung emphysema.

ObjectivesCardiovascular disease is often associated with COPD. Lung density quantification of images obtained from cardiac computed tomography (CT) scans would allow simultaneous evaluation of emphysema and coronary artery calcification score and provide further mechanistic insight into the relationship between these syndromes.Patients and methodsWe assessed the agreement between lung density indices obtained by cardiac and full-lung CT scans. Paired cardiac and chest CT scans were assessed in 156 individuals with and without airflow limitation. Quantitative threshold indices of low attenuation area (LAA) and 15th percentile density index (PD15) were compared in terms of precision using Spearman’s correlation coefficient, accuracy using concordance correlation coefficient (CCC), and relative accuracy using P15 and P30. We also assessed the relationship between visually and quantitatively determined emphysema and used receiver operating characteristic curves to evaluate the ability of lung density indices to discriminate airflow limitation.ResultsCorrelation coefficients between lung density indices obtained from cardiac and chest CT scans were 0.49 for percent LAA (%LAA)-950 and 0.71 for PD15. Corresponding values for CCC, P15, and P30 were 0.33, 3.2, and 5.1, respectively, for %LAA-950, and 0.34, 17.3, and 37.8, respectively, for PD15. For both cardiac and chest CT scans, visually determined emphysema was associated with higher %LAA-950 and lower PD15, and the ability of %LAA-950 and PD15 to discriminate airflow limitation were comparable.ConclusionAlthough chest CT imaging is preferable, cardiac CT imaging may also be used for lung emphysema quantification where association measures are of primary interest.

P1.14-27 Differentiation Between Each Thymic Epithelial Tumor According to WHO Classification Scheme by Using MDCT Findings

Thymic epithelial tumors are the uncommon mediastinal tumors but are the most common primary tumors of the anterior mediastinum. Computed tomography (CT) is the imaging modality of choice for assessment in patients suspected thymic epithelial tumor. The objectives of this study were to assess the CT features of various types of thymic epithelial tumors on the basis of the 2004 WHO classification and to identify the specific CT findings for differentiation between each thymic epithelial tumor. A retrospective study reviewed CT findings of 35 patients with thymic epithelial tumors, who underwent surgical resection from January 2010 to April 2017 and had available pre-operative chest CT study. The tumors were reclassified into six types of thymic epithelial tumors (A, AB, B1, B2, B3 and thymic carcinoma) on the basis of the 2004 WHO classification system. The CT findings including the size (longest diameter), margin, shape, presence of focal area of low attenuation of necrosis or cystic change, mediastinal fat invasion, great vessels invasion, degree and pattern of tumor enhancement, presence of tumor calcification and presence of mediastinal lymphadenopathy (short axis diameter more than 10 mm), the presences of pleural effusion, pleural mass, pulmonary nodule, pericardial effusion and extrathoracic metastasis were evaluated. Our study consisted of 20 (57.14%) men and 15 (42.86%) women, age 15-78 years (mean 51.25 years). Pathological proven into 30 thymomas (85.71%) and 5 cases (14.29%) of thymic carcinomas. The 30 thymomas were classified according to WHO classification; type A in 5 (14.29%), type AB in 4 (11.43%), type B1 in 5 (14.29%), type B2 in 9 (25.71%), and type B3 in 7 (20%) patients. The tumor sizes of type A, AB, B1, B2 and B3 thymomas and thymic carcinoma were 6.2±1.97, 8.1±2.17, 4.9±2.47, 6.8±3.04, 4.7±1.87, and 9.6±2.78 cm, respectively. No definite CT manifestation that distinguishes between each different WHO pathological type of thymoma with statistical significance. The tumor dimension > 8 cm, irregular margin, mediastinal fat invasion, great vessel invasion, lymphadenopathy, pericardial effusion and extrathoracic metastasis could differentiate between thymoma and thymic carcinoma (P-value <0.05). Great vessel invasion and extrathoracic metastasis had high sensitivity (80%), specificity (100%), PPV (100%) and NPV (96.77%) for diagnosis thymic carcinoma. No definite CT manifestation that distinguishes between each different WHO pathological types of thymomas. Tumor size more than 8 cm, irregular margin, presence of mediastinal fat invasion, great vessel invasion, mediastinal lymphadenopathy or extrathoracic metastasis favors the diagnosis of thymic carcinoma.

Effect of the emphysema subtypes of patients with chronic obstructive pulmonary disease on airway inflammation and COTE index.

The aim of the present study was investigate the association of the severity of emphysema of patients with chronic obstructive pulmonary disease (COPD) with airway inflammation and the COPD-specific comorbidity test (COTE) index. A total of 94 patients with COPD were divided into four groups according to the severity of their emphysema; in each patient, comorbidities were recorded and inflammatory biomarkers, including MMP-9 and TIMP-1 were determined in circulating blood. The unbalanced proportion of MMP-9 and its inhibitor, TIMP-1, led to the airway inflammation and lung remodeling in the patients with COPD. A total of 80.85% of the patients had emphysema of different degrees. The quantity of male patients and the smoking index in the three emphysema groups were significantly higher than those in the non-emphysema group (F=7.67 and 5.42, P<0.05). The level of the predicted percent offorced expiratory volume in 1 sec in the non-emphysema group were significantly higher than those in the emphysema group (4.33; P<0.05), and the level of D-dimer in the non-emphysema group was significantly lower than that in the mild and moderate emphysema groups (F=9.38, P<0.05). The low-attenuation area score was negatively correlated with inhaled bronchodilators (r=-0.240, P=0.007) but positively correlated with the frequency of acute exacerbations in the previous year (r=0.211, P=0.001). In terms of treatment, the use of systemic hormone therapy in the emphysema group was more frequent than that in the non-emphysema group (F=6.21, 12.92 and 4.08, P<0.05). The level of MMP-9 was significantly higher in COPD patients with >3 comorbidities, a COTE index of ≥4 and cardiovascular disease as well as coronary heart disease (t=6.40, 2.53, 3.65 and 2.90, P<0.05). The level of MMP-9 was positively correlated with the neutrophilic granulocyte percentage, the number of comorbidities and the COTE index (r=0.193, 0.402 and 0.311, P<0.01). The severity of emphysema in patients with COPD was correlated with the persistence of inflammatory factors in the circulating blood and the frequency of acute exacerbations. It was indicated that MMP-9 has a critical role in numerous comorbidities of COPD.

Fractal analysis of low attenuation clusters on computed tomography in chronic obstructive pulmonary disease

BackgroundThe fractal dimension characterizing the cumulative size distribution of low attenuation area (LAA) clusters, identified with a fixed threshold such as − 950 Hounsfield Units (HU), on computed tomography (CT) sensitively detects parenchymal destruction in chronic obstructive pulmonary disease (COPD) even when the percent LAA (LAA%), a standard emphysema index, is unchanged. This study examines whether the cumulative size distribution of LAA clusters, defined with thresholds of the 15th, 25th, and 35th percentiles of a CT density histogram instead of the fixed-threshold of − 950 HU, exhibits a fractal property and whether its fractal dimension (D’15, D’25, and D’35, respectively) provides additional structural information in emphysematous lungs that is difficult to detect with the conventional − 950-HU-based fractal dimension (D950).MethodsChest inspiratory CT scans and pulmonary functions were cross-sectionally examined in 170 COPD subjects. A proxy for the inspiration level at CT scan was obtained by dividing CT-measured total lung volume (CT-TLV) by physiologically measured total lung capacity. Moreover, long-term (> 5 years) changes in D950 and the new fractal dimensions were longitudinally evaluated in 17 current and 42 former smokers with COPD.ResultsD950, but not D’15, D’25, or D’35 was weakly correlated with the proxy for the inspiration. D950, D’25, and D’35 but not D’15 correlated with LAA% and diffusion capacity. In the long-term longitudinal study, LAA% was increased and D950 and D’35 were decreased in both current and former smokers, while D’25 was decreased only in current smokers and D’15 was not changed in either group. The longitudinal changes in D’25 but not those in LAA%, D950, D’15, and D’35 were greater in current smokers than in former smokers. This greater change in D’25 in current smokers was confirmed after adjusting the change in CT-TLV and the baseline D’25.ConclusionsD’25 reflects diffusion capacity in emphysematous lungs and is robust against inspiration levels during CT scans. This new fractal dimension might provide additional structural information that is difficult to detect with the conventional D950 and LAA% and allow for more sensitive evaluation of emphysema progression over time.

William M. Feinberg Award for Excellence in Clinical Stroke: Small Vessel Disease; a Big Problem, But Fixable.

Like much in stroke, this research journey started with a clot although this clot and this stroke were different.1 Small vessel disease (SVD) is now recognized to cause 20% to 25% of strokes, to be the second commonest cause of dementia, to cause cognitive decline, physical frailty, and late onset depression. In addition to acute small subcortical (lacunar) ischemic strokes, SVD includes lesions seen commonly on brain imaging: white matter hypertensities (WMH), lacunes, microbleeds, perivascular spaces (PVS), brain shrinkage,2 and biomarkers in apparently normal areas (eg, increased tissue fluid volume and mobility).3 However, when this research started, the strokes, cognitive presentations, and neuroimaging features of SVD were thought generally to be unrelated, silent, permanent, and lacunar stroke was a small version of large artery stroke. In 2000 AD, a 70-year-old man presented to our hospital with a recent lacunar stroke. His computed tomographic scan showed a small, low attenuation area, consistent with a recent small subcortical (lacunar) infarct. There were 3 odd features. 1. In the center was a small white dot, like a mini version of the hyperattenuated middle cerebral artery commonly seen in patients with hyperacute cardio- or athero-thromboembolic ischemic stroke, an appearance not described previously. 2. Brain magnetic resonance imaging (MRI) immediately after the computed tomographic scan confirmed the recent lacunar infarct, including the odd central line/dot, except that there also appeared to be some blood in the arteriole wall. Although a few small cardiac or carotid atheromatous emboli can enter the basal perforating arterioles, ≈6% in experimental models,4 and no more than 11% in patients,5 an embolus would not explain the blood in the arteriole wall. 3. The infarct was around the affected arteriolar segment, not at the end of it, as would be expected in, for example, an infarct occurring secondary to an …

Pruning of the Pulmonary Vasculature in Asthma. The Severe Asthma Research Program (SARP) Cohort.

Loss of the peripheral pulmonary vasculature, termed vascular pruning, is associated with disease severity in patients with chronic obstructive pulmonary disease. To determine if pulmonary vascular pruning is associated with asthma severity and exacerbations. We measured the total pulmonary blood vessel volume (TBV) and the blood vessel volume of vessels less than 5 mm2 in cross-sectional area (BV5) and of vessels less than 10 mm2 (BV10) in cross-sectional area on noncontrast computed tomographic scans of participants from the Severe Asthma Research Program. Lower values of the BV5 to TBV ratio (BV5/TBV) and the BV10 to TBV ratio (BV10/TBV) represented vascular pruning (loss of the peripheral pulmonary vasculature). Compared with healthy control subjects, patients with severe asthma had more pulmonary vascular pruning. Among those with asthma, those with poor asthma control had more pruning than those with well-controlled disease. Pruning of the pulmonary vasculature was also associated with lower percent predicted FEV1 and FVC, greater peripheral and sputum eosinophilia, and higher BAL serum amyloid A/lipoxin A4 ratio but not with low-attenuation area or with sputum neutrophilia. Compared with individuals with less pruning, individuals with the most vascular pruning had 150% greater odds of reporting an asthma exacerbation (odds ratio, 2.50; confidence interval, 1.05-5.98; P = 0.039 for BV10/TBV) and reported 45% more asthma exacerbations during follow-up (incidence rate ratio, 1.45; confidence interval, 1.02-2.06; P = 0.036 for BV10/TBV). Pruning of the peripheral pulmonary vasculature is associated with asthma severity, control, and exacerbations, and with lung function and eosinophilia.

Computed tomography quantification of emphysema in people living with HIV and uninfected controls.

People living with HIV (PLWH) may be more susceptible to the development of emphysema than uninfected individuals. We assessed prevalence and risk factors for emphysema in PLWH and uninfected controls. Spirometry and chest computed tomography scans were obtained in PLWH from the Copenhagen Comorbidity in HIV Infection (COCOMO) study and in uninfected controls from the Copenhagen General Population Study (CGPS) who were >40 years. Emphysema was quantified using a low attenuation area < -950 Hounsfield units (%LAA-950) and the 15th percentile density index (PD15) and assessed by semi-quantitative visual scales. Of 742 PLWH, 21.2% and 4.7% had emphysema according to the %LAA-950 threshold with cut-offs at 5% and 10%, respectively. Of 470 uninfected controls, these numbers were 24.3% (p=0.23) and 4.0% (p=0.68). HIV was not associated with emphysema (adjusted OR 1.25, 95% CI 0.68-2.36 for %LAA-950 >10%) by PD15 or by visually assessed emphysema. We found no interaction between HIV and cumulative smoking. Breathlessness and sputum production were more common in PLWH with emphysema, and emphysema seemed to be more prevalent in PLWH with airflow limitation. HIV was therefore not independently associated with emphysema, but the clinical impact of emphysema was greater in PLWH than in uninfected controls.

The pulmonary damage caused by smoking: A longitudinal study.

BACKGROUND:Smoking for a long period is known to cause several harms to the human body, chiefly associated with serious pulmonary damage.OBJECTIVE: The purpose of this study was to evaluate the difference in the pulmonary damage between current smokers and ex-smokers, through measuring the bronchial parameters and the extent of emphysema, in order to further illustrate the harm of smoking and the need to stop smoking.METHODS:Using the FACT-Digital lung TM software quantitatively analysis of CT images, including the WT, WA%, LD, LV, PD, and %LAA-950 was performed. The percentage of low attenuation areas less than -950 Hounsfield units (%LAA-950) was defined as the extent of emphysema. The longitudinal data in the two consecutive years of these current smoker group and ex-smoker group were compared by paired t-test.RESULTS:The LV, %LAA-950, WT and WA% of current smokers increased more rapidly each year than that of ex-smokers. The PD and LD of current smokers declined more rapidly each year than that of ex-smokers.CONCLUSIONS:This study shows that pulmonary damage caused by smoking related to the smoking status, can be measured. Smoking cessation has a positive role in alleviating the progress of pulmonary damage.

Assessment of the correlates of respiratory morbidity related quality of life, using St George Respiratory Questionnaire (SGRQ) among male COPD patients

Background: COPD is ranked eighth among the top 20 conditions causing disability globally. Assessment in subjective areas such as dyspnea and HRQL provides complementary information to physiologic measurements. Lower Health-Related Quality of Life has been associated with mortality and morbidity in COPD.Methods: The study was conducted at the Department of Respiratory Medicine and at Vallabhbhai Patel Chest Institute and the associated, Vishwanathan Chest Hospital, University of Delhi. Between September 2012 to August 2013. We conducted present study on 40 male COPD subjects aged more than 45 years, divided into 4 groups based on CT phenotype as normal, Airway Dominant (AD), Emphysema Dominant (ED) and mixed types. We compared the St. George Respiratory Questionnaire scores, 6 Minutes’ walk Distance scores, Clinical parameters, Spirometry indices across these phenotypes. Results: The mean SGRQ score in present study was 54.07 ± 17.24 (Range :17.3 to 84.57). The Mean 6MWD in present study was 434.58 ± 125.47 metres. The significant parameters which had correlation with SGRQ total score were Age (r=0.343, p = 0.03), 6MWD (-0.397, p = 0.011), FEV1 /FVC (0.499, p&lt; 0.001), DLCO (-0.601, p &lt;0.001), Low attenuation areas in CT (0.606, p&lt; 0.001). Conclusions: 6MWD, FEV1/FVC, age, Low attenuation areas in CT, DLCO had an influence on the quality of life as measured by SGRQ scores in present study. Therapeutic approaches to improve the quality of life in COPD should take these indices into consideration.

CT-based Visual Classification of Emphysema: Association with Mortality in the COPDGene Study.

PurposeTo determine whether visually assessed patterns of emphysema at CT might provide a simple assessment of mortality risk among cigarette smokers.Materials and MethodsOf the first 4000 cigarette smokers consecutively enrolled between 2007 and 2011 in this COPDGene study, 3171 had data available for both visual emphysema CT scores and survival. Each CT scan was retrospectively visually scored by two analysts using the Fleischner Society classification system. Severity of emphysema was also evaluated quantitatively by using percentage lung volume occupied by low-attenuation areas (voxels with attenuation of −950 HU or less) (LAA-950). Median duration of follow-up was 7.4 years. Regression analysis for the relationship between imaging patterns and survival was based on the Cox proportional hazards model, with adjustment for age, race, sex, height, weight, pack-years of cigarette smoking, current smoking status, educational level, LAA-950, and (in a second model) forced expiratory volume in 1 second (FEV1).ResultsObserver agreement in visual scoring was good (weighted κ values, 0.71–0.80). There were 519 deaths in the study cohort. Compared with subjects who did not have visible emphysema, mortality was greater in those with any grade of emphysema beyond trace (adjusted hazard ratios, 1.7, 2.5, 5.0, and 4.1, respectively, for mild centrilobular emphysema, moderate centrilobular emphysema, confluent emphysema, and advanced destructive emphysema, P < .001). This increased mortality generally persisted after adjusting for LAA-950.ConclusionThe visual presence and severity of emphysema is associated with significantly increased mortality risk, independent of the quantitative severity of emphysema.Online supplemental material is available for this article.