Frequency of subclinical interstitial lung disease in COVID-19 autopsy cases: potential risk factors of severe pneumonia.

Risk factors of severe coronavirus disease 2019 (COVID-19) have been previously reported; however, histological risk factors have not been defined thus far. The aim of this study was to clarify subclinical hidden interstitial lung disease (ILD) as a risk factor of severe pneumonia associated with COVID-19. We carefully examined autopsied lungs and chest computed tomography scanning (CT) images from patients with COVID-19 for interstitial lesions and then analyzed their relationship with disease severity. Among the autopsy series, subclinical ILD was found in 13/27 cases (48%) in the COVID-19 group, and in contrast, 8/65 (12%) in the control autopsy group (p = 0.0006; Fisher's exact test). We reviewed CT images from the COVID-19 autopsy cases and verified that subclinical ILD was histologically detectable in the CT images. Then, we retrospectively examined CT images from another series of COVID-19 cases in the Yokohama, Japan area between February-August 2020 for interstitial lesions and analyzed the relationship to the severity of COVID-19 pneumonia. Interstitial lesion was more frequently found in the group with the moderate II/severe disease than in the moderate I/mild disease (severity was evaluated according to the COVID-19 severity classification system of the Ministry of Health, Labor, and Welfare [Japan]) (moderate II/severe, 11/15, 73.3% versus moderate I/mild, 108/245, 44.1%; Fisher exact test, p = 0.0333). In conclusion, it was suggested that subclinical ILD could be an important risk factor for severe COVID-19 pneumonia. A benefit of these findings could be the development of a risk assessment system using high resolution CT images for fatal COVID-19 pneumonia.

Quantitative Analysis for Lung Disease on Thin-Section CT.

Thin-section computed tomography (CT) is widely employed not only for assessing morphology but also for evaluating respiratory function. Three-dimensional images obtained from thin-section CT provide precise measurements of lung, airway, and vessel volumes. These volumetric indices are correlated with traditional pulmonary function tests (PFT). CT also generates lung histograms. The volume ratio of areas with low and high attenuation correlates with PFT results. These quantitative image analyses have been utilized to investigate the early stages and disease progression of diffuse lung diseases, leading to the development of novel concepts such as pre-chronic obstructive pulmonary disease (pre-COPD) and interstitial lung abnormalities. Quantitative analysis proved particularly valuable during the COVID-19 pandemic when clinical evaluations were limited. In this review, we introduce CT analysis methods and explore their clinical applications in the context of various lung diseases. We also highlight technological advances, including images with matrices of 1024 × 1024 and slice thicknesses of 0.25 mm, which enhance the accuracy of these analyses.

Quantitative Computed Tomography Analysis of the Longitudinal Change Between Centrilobular and Paraseptal Emphysema Subtypes: A Retrospective Study.

OBJECTIVE: This study aimed to investigate the difference between the extent of centrilobular emphysema (CLE) and paraseptal emphysema (PSE) on follow-up chest CT scans and their relationship to the cross-sectional area (CSA) of small pulmonary vessels. METHODS: Sixty-two patients (36 CLE and 26 PSE) who underwent 2 chest CT scans were enrolled in this study. The percentage of low attenuation volume (%LAV) and total CSA of the small pulmonary vessels <5 mm 2 (%CSA < 5) were measured at the 2 time points. Analysis of the initial %CSA < 5 and the change in the %LAV and %CSA < 5 on follow-up imaging was performed. RESULTS: The initial %CSA < 5 was not significantly different between the CLE and the PSE groups (CLE, 0.66 vs. PSE, 0.71; P = 0.78). There was no significant difference in the longitudinal change in the %LAV between the 2 groups (CLE, -0.048% vs. PSE, 0.005%; P = 0.26). The longitudinal change in the %CSA < 5 in patients with PSE significantly decreased compared with those with CLE (CLE, 0.025% vs. PSE, -0.018%; P = 0.02). CONCLUSIONS: The longitudinal change in the %CSA < 5 was significantly different for patients with CLE and PSE, demonstrating an important pathophysiological difference between the subtypes.

Concordance between transbronchial lung cryobiopsy and surgical lung biopsy for interstitial lung disease in the same patients.

BACKGROUND: The diagnostic accuracy and safety of transbronchial lung cryobiopsy (TBLC) via a flexible bronchoscope under sedation compared with that of surgical lung biopsy (SLB) in the same patients is unknown. METHODS: Retrospectively the data of fifty-two patients with interstitial lung diseases (median age: 63.5 years; 21 auto-antibody positive) who underwent TBLC followed by SLB (median time from TBLC to SLB: 57 days) was collected. The samples from TBLC and SLB were randomly labelled to mask the relationship between the two samples. Diagnosis was made independently by pathologists, radiologists, and pulmonary physicians in a stepwise manner, and a final diagnosis was made at multidisciplinary discussion (MDD). In each diagnostic step the specific diagnosis, the diagnostic confidence level, idiopathic pulmonary fibrosis (IPF) diagnostic guideline criteria, and treatment strategy were recorded. RESULTS: Without clinical and radiological information, the agreement between the histological diagnoses by TBLC and SLB was 42.3% (kappa [κ] = 0.23, 95% confidence interval [CI]: 0.08-0.39). However, the agreement between the TBLC-MDD and SLB-MDD diagnoses and IPF/non-IPF diagnosis using the two biopsy methods was 65.4% (κ = 0.57, 95% CI: 0.42-0.73) and 90.4% (47/52), respectively. Out of 38 (73.1%) cases diagnosed with high or definite confidence at TBLC-MDD, 29 had concordant SLB-MDD diagnoses (agreement: 76.3%, κ = 0.71, 95% CI: 0.55-0.87), and the agreement for IPF/non-IPF diagnoses was 97.4% (37/38). By adding the pathological diagnosis, the inter-observer agreement of clinical diagnosis improved from κ = 0.22 to κ = 0.42 for TBLC and from κ = 0.27 to κ = 0.38 for SLB, and the prevalence of high or definite diagnostic confidence improved from 23.0% to 73.0% and from 17.3% to 73.0%, respectively. Of all 383 TBLC performed during the same period, pneumothorax occurred in 5.0% of cases, and no severe bleeding, acute exacerbation of interstitial lung disease, or fatal event was observed. CONCLUSIONS: TBLC via a flexible bronchoscope under deep sedation is safely performed, and the TBLC-MDD diagnosis with a high or definite confidence level is concordant with the SLB-MDD diagnosis in the same patients.

Radiological and Pathological Features of Cyst Formation in Idiopathic Multicentric Castleman Disease.

INTRODUCTION: Idiopathic multicentric Castleman disease (MCD) has been reported to form lung cysts at a relatively high rate. However, the radiological and pathological features of cystic formation in MCD are unclear. METHODS: To clarify these questions, we retrospectively investigated the radiological and pathological findings of cysts in MCD patients. Eight consecutive patients who underwent surgical lung biopsies in our center from 2000 to 2019 were included. RESULTS: The median age was 44.5 years, with three males and five females. On the initial computed tomography, cyst formation was found in seven patients (87.5%). All of the cysts were multiple, round, and thin walled, accompanying ground-glass attenuation (GGA) around cysts. In six patients (75%), cysts increased during their clinical courses, and the new cysts had emerged from GGA, although GGA was improved by treatment. In all four cases, whose pulmonary cysts could be pathologically evaluated, a marked plasma cell infiltration around the cyst wall, and loss of elastic fibers of the alveolar wall were observed. CONCLUSIONS: Pulmonary cysts emerged in the area of GGA pathologically consistent with plasma cell infiltration. Cysts in MCD may be formed by the loss of elastic fibers due to marked plasma cell infiltration and may be considered irreversible changes.

Prediction of prognosis in patients with severe COVID-19 pneumonia using CT score by emergency physicians: a single-center retrospective study.

We aimed to develop a method to determine the CT score that can be easily obtained from CT images and examine its prognostic value for severe COVID pneumonia. Patients with COVID pneumonia who required ventilatory management by intubation were included. CT score was based on anatomical information in axial CT images and were divided into three sections of height from the apex to the bottom. The extent of pneumonia in each section was rated from 0 to 5 and summed. The primary outcome was the prediction of patients who died or were managed on extracorporeal membrane oxygenation (ECMO) based on the CT score at admission. Of the 71 patients included, 12 (16.9%) died or required ECMO management, and the CT score predicted death or ECMO management with ROC of 0.718 (0.561-0.875). The death or ECMO versus survival group (median [quartiles]) had a CT score of 17.75 (14.75-20) versus 13 (11-16.5), p = 0.017. In conclusion, a higher score on our generated CT score could predict the likelihood of death or ECMO management. A CT score at the time of admission allows for early preparation and transfer to a hospital that can manage patients who may need ECMO.

Prognostic implication of IgG4 and IgG1-positive cell infiltration in the lung in patients with idiopathic interstitial pneumonia.

Immunoglobulin (Ig) G4-positive cells are rarely observed in the lungs of patients with idiopathic interstitial pneumonias (IIPs). IgG1 may be more pathogenic than IgG4, with IgG4 having both pathogenic and protective roles in IgG4-related disease (IgG4-RD). However, the role of both IgG1 and IgG4 in IIPs remains unclear. We hypothesized that patients with IgG4-positive interstitial pneumonia manifest different clinical characteristics than patients with IgG4-RD. Herein, we identified the correlation of the degree of infiltration of IgG1- and IgG4-positive cells with IIP prognosis, using a Japanese nationwide cloud-based database. We included eighty-eight patients diagnosed with IIPs after multidisciplinary discussion, from April 2009 to March 2014. IgG4-positive cell infiltration was identified in 12/88 patients with IIPs and 8/41 patients with idiopathic pulmonary fibrosis (IPF). Additionally, 31/88 patients with IIPs and 19/41 patients with IPF were diagnosed as having IgG1-positive cell infiltration. IgG4-positive IIPs tended to have a better prognosis. Conversely, overall survival in cases with IgG1-positive IPF was significantly worse. IIPs were prevalent with IgG1- or IgG4-positive cell infiltration. IgG1-positive cell infiltration in IPF significantly correlated with a worse prognosis. Overall, evaluating the degree of IgG1-positive cell infiltration may be prognostically useful in cases of IPF.

Radiological pleuroparenchymal fibroelastosis-like lesion in idiopathic interstitial pneumonias.

BACKGROUND: Pleuroparenchymal fibroelastosis (PPFE) is characterised by predominant upper lobe pleural and subpleural lung parenchymal fibrosis. Radiological PPFE-like lesion has been associated with various types of interstitial lung diseases. However, the prevalence and clinical significance of radiological PPFE-like lesion in patients with idiopathic interstitial pneumonias (IIPs) are not fully understood. We aimed to determine the prevalence and clinical impact on survival of radiological PPFE-like lesion in patients with IIPs. METHODS: A post-hoc analysis was conducted using data from the Japanese nationwide cloud-based database of patients with IIPs. All the patients in the database were diagnosed as having IIPs by multidisciplinary discussion. Patients diagnosed with idiopathic PPFE were excluded. Clinical data and chest computed tomography (CT) image of 419 patients with IIPs were analysed. The presence of radiological PPFE-like lesion was independently evaluated by two chest radiologists blind to the clinical data. RESULTS: Of the 419 patients with IIPs, radiological PPFE-like lesions were detected in 101 (24.1%) patients, mainly in idiopathic pulmonary fibrosis (IPF) and unclassifiable IIPs, but less in idiopathic nonspecific interstitial pneumonia. Prognostic analyses revealed that radiological PPFE-like lesion was significantly associated with poor outcome in patients with IIPs, which was independent of age, IPF diagnosis and %FVC. In survival analyses, the patients with radiological PPFE-like lesions had poor survival compared with those without (log-rank, p < 0.0001). Subgroup analyses demonstrated that radiological PPFE-like lesion was significantly associated with poor survival both in patients with IPF and those with unclassifiable IIPs. CONCLUSION: Radiological PPFE-like lesion is a condition that could exist in IIPs, mainly in IPF and unclassifiable IIPs. Importantly, the radiological PPFE-like lesion is a non-invasive marker to predict poor outcome in patients with IIPs, which should be carefully considered in clinical practice.

Preoperative CT Findings for Predicting Acute Exacerbation of Interstitial Pneumonia After Lung Cancer Surgery: A Multicenter Case-Control Study.

BACKGROUND. Acute exacerbation (AE) is a life-threatening complication of inter-stitial pneumonia (IP). Thoracic surgery may trigger AE. OBJECTIVE. The purpose of this study is to explore the role of preoperative CT findings in predicting postoperative AE in patients with IP and lung cancer. METHODS. This retrospective case-control study included patients from 22 institutions who had IP and underwent thoracic surgery for lung cancer. AE was diagnosed on the basis of symptoms and imaging findings noted within 30 days after surgery and the absence of alternate causes. For each patient with AE, two control patients without AE were identified. After exclusions, the study included 92 patients (78 men and 14 women; 31 with AE [the AE group] and 61 without AE [the no-AE group]; mean age, 72 years). Two radiologists independently reviewed preoperative thin-slice CT examinations for pulmonary findings and resolved differences by consensus. The AE and no-AE groups were compared using the Fisher exact and Mann-Whitney U tests. Multivariable logistic regression was performed. Interreader agreement was assessed by kappa coefficients. RESULTS. A total of 94% of patients in the AE group underwent segmentectomy or other surgery that was more extensive than wedge resection versus 75% in the no-AE group (p = .046). The usual IP pattern was present in 58% of the AE group versus 74% of the no-AE group (p = .16). According to subjective visual scoring, the mean (± SD) ground-glass opacity (GGO) extent was 6.3 ± 5.4 in the AE group versus 3.9 ± 3.8 in the no-AE group (p = .03), and the mean consolidation extent was 0.5 ± 1.2 in the AE group versus 0.1 ± 0.3 in the no-AE group (p = .009). Mean pulmonary trunk diameter was 28 ± 4 mm in the AE group versus 26 ± 3 mm in the no-AE group (p = .02). In a model of CT features only, independent predictors of AE (p < .05) were GGO extent (odds ratio [OR], 2.8), consolidation extent (OR, 9.4), and pulmonary trunk diameter (OR, 4.2); this model achieved an AUC of 0.75, a PPV of 71%, and an NPV of 77% for AE. When CT and clinical variables were combined, undergoing segmentectomy or more extensive surgery also independently predicted AE (OR, 8.2; p = .02). CONCLUSION. The presence of GGO, consolidation, and pulmonary trunk enlargement on preoperative CT predicts AE in patients with IP who are undergoing lung cancer surgery. CLINICAL IMPACT. Patients with IP and lung cancer should be carefully managed when predictive CT features are present. Wedge resection, if possible, may help reduce the risk of AE in these patients. TRIAL REGISTRATION. University Hospital Medical Information Clinical Trial Registry UMIN000029661.

Investigation of Cushing's and subclinical Cushing's syndromes using adrenocortical scintigraphy.

OBJECTIVES: This study assessed the factors related to the intake rate of adrenocortical scintigraphy in Cushing's and subclinical Cushing's syndromes, in addition to the methods for differentiating between the two. METHODS: Clinical findings, blood sampling, and adrenocortical scintigraphy collected at St. Marianna University School of Medicine from 1 January 2010 to 31 December 2019 were used to diagnose initial-onset Cushing's syndrome and subclinical Cushing's syndrome, and patients who underwent 131I-NP-59 adrenocortical scintigraphy were used as study subjects. RESULTS: A total of 24 (8 male and 16 female) patients were selected. Of them, 7 had Cushing's syndrome and 17 had subclinical Cushing's syndrome. A correlation coefficient of -0.474 (P = 0.026) was determined between the intake rate after 7 days and adrenocorticotropic hormone levels. Intake rates after 5 days were 0.51% and 0.31% for Cushing's and subclinical Cushing's syndromes, respectively, and were statistically significant (P = 0.03). Intake rates after 7 days were 0.47% and 0.30% for Cushing's and subclinical Cushing's syndromes, respectively, and were statistically significant (P = 0.04). Receiver operating characteristic analysis results of Cushing's and subclinical Cushing's syndromes for intake rates after 7 days were as follows: cutoff value, 0.248; area under curve, 0.769; and 95% confidence interval, 0.561-0.977. CONCLUSION: There were differences in the intake rates of adrenocortical scintigraphy between the Cushing's syndrome group and subclinical Cushing's syndrome group, making it possible to differentiate between the two using the intake rate.

CT texture analysis of mediastinal lymphadenopathy: Combining with US-based elastographic parameter and discrimination between sarcoidosis and lymph node metastasis from small cell lung cancer.

OBJECTIVES: To investigate the potential of computed tomography (CT)-based texture analysis and elastographic data provided by endobronchial ultrasonography (EBUS) for differentiating the mediastinal lymphadenopathy by sarcoidosis and small cell lung cancer (SCLC) metastasis. METHODS: Sixteen patients with sarcoidosis and 14 with SCLC were enrolled. On CT images showing the largest mediastinal lymph node, a fixed region of interest was drawn on the node, and texture features were automatically measured. Among the 30 patients, 19 (12 sarcoidosis and 7 SCLC) underwent endobronchial ultrasound transbronchial needle aspiration, and the fat-to-lesion strain ratio (FLR) was recorded. Texture features and FLRs were compared between the 2 patient groups. Logistic regression analysis was performed to evaluate the diagnostic accuracy of these measurements. RESULTS: Of the 31 texture features, the differences between 11 texture features of CT ROIs in the patients with sarcoidosis versus patients with SCLC were significant. Among them, the grey-level run length matrix with high gray-level run emphasis (GLRLM-HGRE) showed the greatest difference (P<0.01). Differences between FLRs were significant (P<0.05). Logistic regression analysis together with receiver operating characteristic curve analysis demonstrated that the FLR combined with the GLRLM-HGRE showed a high diagnostic accuracy (100% sensitivity, 92% specificity, 0.988 area under the curve) for discriminating between sarcoidosis and SCLC. CONCLUSION: Texture analysis, particularly combined with the FLR, is useful for discriminating between mediastinal lymphadenopathy caused by sarcoidosis from that caused by metastasis from SCLC.

Longitudinal changes in structural lung abnormalities using MDCT in chronic obstructive pulmonary disease with asthma-like features.

BACKGROUND: Some patients with chronic obstructive pulmonary disease (COPD) have asthma-like features. However, there have been few reports on the structural lung abnormalities found in this patient population. Multi-detector computed tomography (MDCT) can detect emphysematous low-attenuation areas (LAA) within the lung, airway thickness (wall area percentage, WA%), and the loss of pulmonary vasculature as the percentage of small pulmonary vessels with cross-sectional area (CSA) less than 5 mm2 (%CSA<5). We analyzed differences in structural lung changes over time between patients with COPD and those with COPD with asthma-like features using these CT parameters. MATERIAL AND METHODS: We performed pulmonary function tests (PFTs), MDCT, and a COPD assessment test (CAT) in 50 patients with COPD and 29 patients with COPD with asthma-like features at the time of enrollment and two years later. We analyzed changes in clinical parameters and CT indices over time and evaluated differences in structural changes between groups. RESULTS: The CAT score and FEV1 did not significantly change during the follow-up period in either group. Emphysematous LAA regions significantly increased in both groups. The %CSA<5 showed a small but significant increase in COPD patients, but a significant decrease in patients with COPD with asthma-like features. The WA% at the distal bronchi was significantly decreased in COPD, but did not significantly change in COPD with asthma -like features. CONCLUSION: Emphysematous LAA increased in patients with COPD with and without asthma-like features. The %CSA<5 and WA% at the distal bronchi did not change in parallel with LAA. Furthermore, changes in %CSA<5 were significantly different between patients with COPD and those with COPD with asthma-like features. Patients with COPD with asthma-like features may have different longitudinal structural changes than those seen in COPD patients.

Comparison of diagnostic precision for bone metastasis of primary breast cancer between BONENAVI version 1 and BONENAVI version 2.

OBJECTIVE: The aim of this study was to compare the diagnostic precision of bone scintigraphy with BONENAVI version 1 and BONENAVI version 2 in bone metastasis of primary breast cancer. METHODS: The subjects were 56 consecutive patients (all women, mean age 59 ± 12.7 years) who underwent bone scintigraphy with Tc-MDP and were diagnosed with bone metastasis of primary breast cancer from January 2012 to November 2014. Bone scintigraphy was performed with BONENAVI version 1 and BONENAVI version 2 to calculate artificial neural network (ANN), bone scan index (BSI), and hot-spot values, with ANN ≥ 0.5 considered to reflect bone metastasis for the calculation of sensitivity. Mean ANN, BSI, hot-spot values, and sensitivity were compared between BONENAVI version 1 and BONENAVI version 2, with P < 0.05 considered a significant difference. RESULTS: With BONENAVI version 1, mean ANN was 0.73 ± 0.29, BSI was 1.47 ± 1.85, the hot-spot value was 12.4 ± 12.5, and sensitivity was 76.8% (43/56). With BONENAVI version 2, the mean ANN was 0.86 ± 0.19, BSI was 1.53 ± 2.09, hot-spot value was 12.9 ± 15.6, and sensitivity was 94.6% (53/56). BONENAVI version 2 yielded significantly better ANN and sensitivity than BONENAVI version 1 (both P < 0.01). CONCLUSION: BONENAVI version 2 has improved sensitivity for detecting bone metastasis of primary breast cancer compared to BONENAVI version 1.

Computer-aided Quantification of Pulmonary Fibrosis in Patients with Lung Cancer: Relationship to Disease-free Survival.

Background Interstitial lung abnormalities (ILAs) are present at CT in about 10% of individuals undergoing lung cancer screening. The relationship between histologic findings of ILAs and their influence on patient prognosis remains unknown. Purpose To evaluate the percentage of ILAs at preoperative CT, as measured by radiologists and a computer-aided detection (CAD) software, as a predictor of disease-free survival in patients with lung cancer. Materials and Methods This retrospective study evaluated 217 consecutive patients who underwent complete resection of lung cancer from April 2010 to December 2015. Two radiologists, blinded to the patients' clinical information, scored percentage fibrosis extent and determined whether ILAs and the usual interstitial pneumonia (UIP) pattern were present. They assessed ILA progression at follow-up CT. Two pathologists determined the presence of an UIP pattern. Percentage fibrosis extent was also measured by using CAD. Binary logistic regression analysis was performed to determine whether the CAD percentage fibrosis extent was associated with ILA at CT. Multivariable Cox regression analysis was used to evaluate the significance of CAD percentage fibrosis extent as a predictor of prognosis. Results The radiologists classified 47 patients with ILAs and 24 patients with a UIP pattern at chest CT. The pathologists detected a UIP pattern in 25 patients. CT abnormalities showed progression over a 2-year period in all patients with histologic evidence of UIP. After adjustment for age, sex, and smoking index, the CAD percentage fibrosis extent was independently associated with ILA (odds ratio: 3.1; 95% confidence interval [CI]: 2.1, 4.7; P < .001). After adjustment for age, forced expiratory volume in 1 second (percentage predicted) radiologist-assessed percentage fibrosis extent, and pathologic stage, CAD percentage fibrosis extent was independently associated with worse disease-free survival (hazard ratio: 1.3; 95% CI: 1.1, 1.6; P < .001). Conclusion Greater computer-aided detection percentage fibrosis extent at preoperative CT independently predicted worse disease-free survival in patients with lung cancer. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Goo in this issue.

Nationwide cloud-based integrated database of idiopathic interstitial pneumonias for multidisciplinary discussion.

Multidisciplinary discussion (MDD) requiring close communication between specialists (clinicians, radiologists and pathologists) is the gold standard for the diagnosis of idiopathic interstitial pneumonias (IIPs). However, MDD by specialists is not always feasible because they are often separated by time and location. An online database would facilitate data sharing and MDD. Our aims were to develop a nationwide cloud-based integrated database containing clinical, radiological and pathological data of patients with IIPs along with a web-based MDD system, and to validate the diagnostic utility of web-based MDD in IIPs.Clinical data, high-resolution computed tomography images and lung biopsy slides from patients with IIPs were digitised and uploaded to separate servers to develop a cloud-based integrated database. Web-based MDD was performed using the database and video-conferencing to reach a diagnosis.Clinical, radiological and pathological data of 524 patients in 39 institutions were collected, uploaded and incorporated into the cloud-based integrated database. Subsequently, web-based MDDs with a pulmonologist, radiologist and pathologist using the database and video-conferencing were successfully performed for the 465 cases with adequate data. Overall, the web-based MDD changed the institutional diagnosis in 219 cases (47%). Notably, the MDD diagnosis yielded better prognostic separation among the IIPs than did the institutional diagnosis.This is the first study of developing a nationwide cloud-based integrated database containing clinical, radiological and pathological data for web-based MDD in patients with IIPs. The database and the web-based MDD system that we built made MDD more feasible in practice, potentially increasing accurate diagnosis of IIPs.

The Association Between Bronchial Wall CT Attenuation and Spirometry in Patients with Bronchial Asthma.

RATIONALE AND OBJECTIVE: The purpose of this study was to evaluate the correlation between generation-based bronchial wall attenuation on thin-section computed tomography (CT) scans and airflow limitation in patients with bronchial asthma. MATERIALS AND METHODS: This study included 28 bronchial asthma patients (13 men, 15 women; age range, 23-89 years) who underwent both chest CT and spirometry. On CT, the mean values of peak wall attenuation, wall area percentage, and luminal area were measured in the segmental, subsegmental, and sub-subsegmental bronchi of the right B1 and B10 bronchi. Correlations of the CT measurements with forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC), percent predicted forced expiratory flow at 25%-75% of the FVC (%pred forced expiratory flow25-75), and percent predicted peak flow rate were evaluated with Spearman's rank correlation test. RESULTS: The peak wall attenuation of each generation of segmental bronchi significantly correlated with the forced expiratory volume in 1 second/FVC (B1 segmental, ρ = -0.683, p < 0.0001; B1 subsegmental, ρ = -0.875, p < 0.0001; B1 sub-subsegmental, ρ = -0.926, p < 0.0001; B10 segmental, ρ = -0.811, p < 0.0001; B10 subsegmental, ρ = -0.903, p < 0.0001; B10 sub-subsegmental ρ = -0.950, p < 0.0001). Similar correlations were found between the peak wall attenuation and %pred forced expiratory flow 25-75 or percent predicted peak flow rate. Overall, the correlation coefficients were relatively high in the more peripheral bronchial generations. In all measurements, the coefficients of the peak wall attenuations were higher than those of the wall area percentage and luminal area. CONCLUSION: Peak attenuation of the bronchial wall, particularly in the peripheral bronchi, measured on CT is a good biomarker for the severity of bronchial asthma.

Quantitative CT Evaluation of Small Pulmonary Vessels in Patients with Acute Pulmonary Embolism.

RATIONALE AND OBJECTIVES: The objective of this study was to investigate the correlation between the computed tomography (CT) cross-sectional area (CSA) of small pulmonary vessels and the CT obstruction index in patients with acute pulmonary embolism (PE) and the correlation between the changes in these measurements after anticoagulant therapy. MATERIALS AND METHODS: Fifty-two patients with acute PE were selected for this study. We measured the CSA less than 5 mm2 on coronal reconstructed images to obtain the percentage of the CSA (%CSA < 5). CT angiographic index was obtained based on the Qanadli method for the evaluation of the degree of pulmonary arterial obstruction. Spearman rank correlation analysis was used to evaluate the relationship between the initial and the follow-up values and changes in the %CSA < 5 and the CT obstruction index. RESULTS: There was no significant correlation between the %CSA < 5 and CT obstruction index on both initial (ρ = -0.03, P = 0.84) and follow-up (ρ = -0.03, P = 0.82) assessments. In contrast, there was a significant negative correlation between the changes in %CSA < 5 and the CT obstruction index (ρ = -0.59, P < 0.0001). CONCLUSIONS: Although the absolute %CSA < 5 and CT obstruction index were not significantly correlated, the changes in the values of the two parameters had a significant correlation. Changes in %CSA < 5, which can be obtained easily, can be used as biomarker of therapeutic response in patients with acute PE.

Correlation between heart size and emphysema in patients with chronic obstructive pulmonary disease: CT-based analysis using inspiratory and expiratory scans.

The objective of this study was to investigate the relationship between the extent of emphysema and heart size in patients with chronic obstructive pulmonary disease (COPD) using inspiratory and expiratory chest computed tomography (CT). This retrospective study was approved by the institutional review board and informed consent was waived. We measured lung volume (LV), low attenuation area percent (%LAA; less than or equal to -950 HU), maximum cardiac area, and maximum transverse cardiac diameter on inspiratory/expiratory chest CT in 60 patients with COPD. Spearman rank correlation analysis was used to determine the correlations between the heart and lung CT measurements, and the correlations between these measurements and spirometric values. On inspiratory CT, the maximum transverse cardiac diameter was negatively correlated with LV ( ρ = -0.42; p < 0.01) and %LAA ( ρ = -0.43; p < 0.001). Furthermore, on expiratory CT, the maximum cardiac area was negatively correlated with LV ( ρ = -0.35; p < 0.01) and %LAA ( ρ = -0.37; p < 0.01), and there was a negative correlation between transverse cardiac diameter and %LAA ( ρ = -0.34; p < 0.01). Although inspiratory cardiac size was not correlated with any of the spirometric values, the maximum cardiac area and transverse diameter on expiratory scans were significantly correlated with the reduced airflow values on spirometry ( p < 0.01). In patients with COPD, the transverse cardiac diameter decreased as the emphysema progressed. A smaller cardiac area on expiratory CT suggested the presence of large LVs, emphysema, and airflow limitation in COPD.

Selective venous sampling for primary hyperparathyroidism: how to perform an examination and interpret the results with reference to thyroid vein anatomy.

Primary hyperparathyroidism (pHPT) causes hypercalcemia. The treatment for pHPT is surgical dissection of the hyperfunctioning parathyroid gland. Lower rates of hypocalcemia and recurrent laryngeal nerve injury imply that minimally invasive parathyroidectomy (MIP) is safer than bilateral neck resection. Current trends in MIP use can be inferred only by reference to preoperative localization studies. Noninvasive imaging studies (typically preoperative localization studies) show good detection rates of hyperfunctioning glands; however, there have also been cases of nonlocalization or discordant results. Selective venous sampling (SVS) is an invasive localization method for detecting elevated intact parathyroid hormone in the thyroid and/or internal jugular and brachiocephalic veins. SVS was developed mainly for postoperative patients with persistent or recurrent pHPT; however, SVS could also be useful before initial operations due to its high sensitivity to pHPT. Currently, SVS is generally indicated for recurrent HPT, and for cases with negative imaging study results for HPT or discordant results. Multi-detector row helical CT is useful for imaging the anatomy of the jugular and thyroid veins. Knowledge of the thyroid vein anatomy enables the creation of sampling points in the internal jugular and brachiocephalic veins for catheterization of the thyroid veins and venous anastomoses.

Longitudinal changes in structural abnormalities using MDCT in COPD: do the CT measurements of airway wall thickness and small pulmonary vessels change in parallel with emphysematous progression?

BACKGROUND: Recent advances in multidetector computed tomography (MDCT) facilitate acquiring important clinical information for managing patients with COPD. MDCT can detect the loss of lung tissue associated with emphysema as a low-attenuation area (LAA) and the thickness of airways as the wall area percentage (WA%). The percentage of small pulmonary vessels <5 mm2 (% cross-sectional area [CSA] <5) has been recently recognized as a parameter for expressing pulmonary perfusion. We aimed to analyze the longitudinal changes in structural abnormalities using these CT parameters and analyze the effect of exacerbation and smoking cessation on structural changes in COPD patients. METHODS: We performed pulmonary function tests (PFTs), an MDCT, and a COPD assessment test (CAT) in 58 patients with COPD at the time of their enrollment at the hospital and 2 years later. We analyzed the change in clinical parameters including CT indices and examined the effect of exacerbations and smoking cessation on the structural changes. RESULTS: The CAT score and forced expiratory volume in 1 second (FEV1) did not significantly change during the follow-up period. The parameters of emphysematous changes significantly increased. On the other hand, the WA% at the distal airways significantly decreased or tended to decrease, and the %CSA <5 slightly but significantly increased over the same period, especially in ex-smokers. The parameters of emphysematous change were greater in patients with exacerbations and continued to progress even after smoking cessation. In contrast, the WA% and %CSA <5 did not change in proportion to emphysema progression. CONCLUSION: The WA% at the distal bronchi and the %CSA <5 did not change in parallel with parameters of LAA over the same period. We propose that airway disease and vascular remodeling may be reversible to some extent by smoking cessation and appropriate treatment. Optimal management may have a greater effect on pulmonary vascularity and airway disease than parenchymal deconstruction in the early stage of COPD.