The diagnosis of early pneumoconiosis in dust-exposed workers: comparison of chest radiography and computed tomography.

BACKGROUND: Chest radiography (CR) is employed as the evaluation of pneumoconiosis; however, we sometimes encounter cases in which computed tomography (CT) is more effective in detecting subtle pathological changes or cases in which CR yields false-positive results. PURPOSE: To compare CR to CT in the diagnosis of early-stage pneumoconiosis. MATERIAL AND METHODS: CR and CT were performed for 132 workers with an occupational history of mining. We excluded 23 cases of arc-welder's lung. Five readers who were experienced chest radiologists or pulmonologists independently graded the pulmonary small opacities on CR of the remaining 109 cases. We then excluded 37 cases in which the CT data were not sufficient for grading. CT images of the remaining 72 cases were graded by the five readers. We also assessed the degree of pulmonary emphysema in those cases. RESULTS: The grade of profusion on CR (CR score) of all five readers was identical in only 5 of 109 cases (4.6%). The CR score coincided with that on CT in 40 of 72 cases (56%). The CT score was higher than that on CR in 13 cases (18%). On the other hand, the CT score was lower than that on CR in 19 cases (26%). The incidence of pulmonary emphysema was significantly higher in patients whose CR score was higher than their CT score. CONCLUSION: CT is more sensitive than CR in the evaluation of early-stage pneumoconiosis. In cases with emphysema, the CR score tends to be higher in comparison to that on CT.

Double region of interest timing bolus technique following endovascular aortic repair: Short-term prognosis analysis.

OBJECTIVES: To compare the incidence rate of reintervention in patients with and without complication findings at aortic computed tomography using double region of interest timing bolus (DRTB) method after endovascular stent placement of the aorta. METHODS: We included 40 patients who underwent computed tomography of the aorta using DRTB method after endovascular stent placement. DRTB method allows to scan the aorta with a short injection time of 9 s by synchronizing the scan speed to the aortic flow. Complication findings at computed tomography were defined as endoleak, rupture, occlusion, and infection. The primary endpoint was reintervention, which was defined as any of the following three events: conversion to open repair, graft revision, or secondary intervention. RESULTS: The mean contrast medium during computed tomography angiography was 38.6 ± 3.9 mL. Complication findings at computed tomography were present in 10 patients (25%): endoleak (n = 9) and infection (n = 1). During a median follow-up of 7 months (interquartile range, 4-11 months), two patients experienced reintervention. Kaplan-Meier curves by complication findings showed that event rate at 6 months was significantly higher in patients with complication findings than in patients without (20% vs 0%, p = 0.01). No patients without complication findings at computed tomography experienced reintervention. CONCLUSIONS: No complication findings at computed tomography after intervention of the aorta resulted in good prognosis in patients who underwent aortic computed tomography using DRTB method.

Double ROI Timing Bolus Technique to Perform Aortic CT Angiography With a 9-Second Contrast Injection Duration.

OBJECTIVE. The purpose of this study was to investigate the feasibility of a double ROI timing bolus technique for performing aortic CT angiography (CTA) with 40 mL of contrast medium over 9 seconds. SUBJECTS AND METHODS. A prospective study from February to July 2018 included 106 patients with clinical indications for evaluation of aortic aneurysm or dissection or suspected aortic disease. Forty-seven of these patients had undergone prior aortic CTA by the conventional method. The scanning speed for the double ROI timing bolus technique was calculated from the time-attenuation curves of the ascending and descending aorta by use of the timing bolus data to synchronize aortic flow. The conventional scan was obtained by injection of 1.7 mL of contrast medium per kilogram of body weight for 25 seconds. Enhancement of six points on the aortoiliac arteries and superior vena cava was measured. The t test was used to compare the values. RESULTS. Use of the double ROI timing bolus method significantly reduced the amount of contrast medium injected compared with the amount for the conventional method (40.0 mL vs 88.0 ± 9.4 mL, p < 0.001). Use of the method significantly increased aortoiliac enhancement (403.3 ± 76.0 HU vs 359.7 ± 61.5 HU, p < 0.001) and significantly decreased enhancement of the superior vena cava (118.9 ± 46.2 HU vs 239.2 ± 130.5 HU, p < 0.001) compared with the conventional method. In the group with prior CTA images available, the effective dose was significantly lower with the double ROI timing bolus than with the conventional method (8.3 ± 1.7 mSv vs 12.4 ± 3.2 mSv, p < 0.01). CONCLUSION. Use of the double ROI timing bolus method can dramatically reduce the amount of contrast medium used during aortic CTA while improving aortic enhancement and reducing radiation dose.

Asbestosis and other pulmonary fibrosis in asbestos-exposed workers: high-resolution CT features with pathological correlations.

OBJECTIVE: The purpose was to identify distinguishing CT features of pathologically diagnosed asbestosis, and correlate diagnostic confidence with asbestos body burden. METHODS: Thirty-three workers (mean age at CT: 73 years) with clinical diagnoses of asbestosis, who were autopsied (n = 30) or underwent lobectomy (n = 3), were collected. Two radiologists independently scored high-resolution CT images for various CT findings and the likelihood of asbestosis was scored. Two pathologists reviewed the pathology specimens and scored the confidence of their diagnoses. Asbestos body count was correlated with CT and pathology scores. RESULTS: Pathologically, 15 cases were diagnosed as asbestosis and 18 cases with various lung fibroses other than asbestosis. On CT, only the score of the subpleural curvilinear lines was significantly higher in asbestosis (p = 0.03). Accuracy of CT diagnosis of asbestosis with a high confidence ranged from 0.73 to 0.79. Asbestos body count positively correlated with CT likelihood of asbestosis (r = 0.503, p = 0.003), and with the confidence level of pathological diagnosis (r = 0.637, p < 0.001). CONCLUSIONS: Subpleural curvilinear lines were the only clue for the diagnosis of asbestosis. However, this was complicated by other lung fibrosis, especially at low asbestos body burden. KEY POINTS: • Various patterns of pulmonary fibrosis occurred in asbestos-exposed workers. • The fibre burden in lungs paralleled confident CT diagnosis of asbestosis. • The fibre burden in lungs paralleled confident pathological diagnosis of asbestosis. • Subpleural curvilinear lines were an important CT finding favouring asbestosis.

Final safety and efficacy of erlotinib in the phase 4 POLARSTAR surveillance study of 10 708 Japanese patients with non-small-cell lung cancer.

Interstitial lung disease (ILD) occurrence and risk factors were investigated in the Japanese non-small-cell lung cancer, post-marketing, large-scale surveillance study, POLARSTAR. All patients with unresectable, recurrent/advanced non-small-cell lung cancer who were treated with erlotinib in Japan between December 2007 and October 2009 were enrolled. Primary endpoints were patterns of ILD and risk factors for onset of ILD and ILD-related death. Overall survival, progression-free survival, and occurrence of adverse drug reactions were secondary endpoints. Interstitial lung disease was confirmed in 429 (4.3%) patients. Concurrent/previous ILD (hazard ratio, 3.19), emphysema or chronic obstructive pulmonary disease (hazard ratio, 1.86), lung infection (hazard ratio, 1.55), smoking history (hazard ratio, 2.23), and period from initial cancer diagnosis to the start of treatment (<360 days; hazard ratio, 0.58) were identified as significant risk factors for developing ILD by Cox multivariate analysis. Logistic regression analysis identified Eastern Cooperative Oncology Group performance status 2-4 (odds ratio, 2.45 [95% confidence interval, 1.41-4.27]; P = 0.0016), ≤50% remaining normal lung area (odds ratio, 3.12 [1.48-6.58]; P = 0.0029), and concomitant honeycombing with interstitial pneumonia (odds ratio, 6.67 [1.35-32.94]; P = 0.02) as poor prognostic factors for ILD death. Median overall survival was 277 days; median progression-free survival was 67 days. These data confirm the well-characterized safety profile of erlotinib. Interstitial lung disease is still an adverse drug reaction of interest in this population, and these results, including ILD risk factors, give helpful information for treatment selection and monitoring. Erlotinib efficacy was additionally confirmed in this population. (POLARSTAR trial ML21590.).

Pathologically proved nonspecific interstitial pneumonia: CT pattern analysis as compared with usual interstitial pneumonia CT pattern.

PURPOSE: To assess the variability of computed tomography (CT) patterns in patients with pathologic nonspecific interstitial pneumonia (NSIP) and to evaluate correlation of CT patterns with new idiopathic pulmonary fibrosis (IPF) classification guidelines, including pathologic diagnosis and predicted mortality. MATERIALS AND METHODS: The ethical review boards of the five institutions that contributed cases waived the need for informed consent for retrospective review of patient records and images. The study included 114 patients with (a) a pathologic diagnosis of idiopathic NSIP (n = 39) or (b) a pathologic diagnosis of usual interstitial pneumonia (UIP) and a clinical diagnosis of IPF (n = 75). Two groups of independent observers evaluated the extent and distribution of various CT findings and identified the following five patterns: UIP, possible UIP, indeterminate (either UIP or NSIP), NSIP, and suggestive of an alternative diagnosis. CT findings were compared with pathologic diagnoses and outcome from clinical findings by using the log-rank test and Kaplan-Meier curves. RESULTS: Radiologists classified 17 cases as UIP, 24 as possible UIP, 13 as indeterminate (either UIP or NSIP), and 56 as NSIP. In 35 of 39 patients with pathologic NSIP, a diagnosis of NSIP was made with CT. On the basis of CT interpretations, the mean overall survival time of patients with UIP, possible UIP, indeterminate findings, or NSIP was 33.5, 73.0, 101.0, and 140.2 months, respectively. Outcome of patients with a CT diagnosis of UIP was significantly worse than that of patients with a pattern of possible UIP, indeterminate findings, or NSIP (log-rank test: P = .013, P = .018, and P < .001, respectively). CONCLUSION: CT pattern in patients with pathologic NSIP is more uniform than that in patients with pathologic UIP, and CT NSIP pattern is associated with better patient outcome than is CT UIP pattern.

Changing patterns of pulmonary abnormalities in rheumatoid arthritis.

BACKGROUND: As a first step in identifying the developmental pathways of pulmonary abnormalities in rheumatoid arthritis (RA), we sought to determine the existing and changing patterns of pulmonary abnormalities. METHODS: We conducted a retrospective cohort study of consecutive patients with RA who underwent high-resolution computed tomography before and during biologic therapy. The presence of 20 pulmonary abnormalities and the changes in those abnormalities were recorded. Patterns of pre-existing and changing abnormalities were examined via cluster analysis, and their relationship was also assessed using the Kaplan-Meier method and log-rank test. RESULTS: A total of 208 subjects were included. Pulmonary abnormalities were observed in 70% of patients: 39% had interstitial lung disease, and 55% had airway disease (AD). Several different pulmonary abnormalities were commonly found to co-exist in several patterns in the same patient. In most patients with pulmonary abnormalities, AD was present alone or in combination with other abnormalities. During the observation period (mean 3.2 years), 172 pulmonary abnormalities had changed in 91 patients: 115 pulmonary abnormalities newly emerged, whereas 42 worsened and 25 demonstrated improvement. Pulmonary abnormalities changed in several patterns. Correlations were observed between pre-existing and new/worsening abnormalities at individual and regional levels, such as new ground-glass opacity (GGO) and pre-existing AD, small nodular patterns, and honeycombing. AD was a possible initial abnormality. CONCLUSIONS: Pulmonary abnormalities occurred and changed in several patterns, which suggests the existence of developmental pathways of pulmonary abnormalities. AD may play an important role in the development of these abnormalities, including GGO.

Lung cancer in chronic interstitial pneumonia: early manifestation from serial CT observations.

OBJECTIVE: The purpose of this study was to use serial CT observations to characterize early-stage lung cancer in patients with chronic interstitial pneumonia. MATERIALS AND METHODS: We found 23 lung cancers in 22 patients during routine follow-up of chronic interstitial pneumonia between 1999 and 2010. Patients with lung cancer found at initial CT were excluded. Two radiologists independently reviewed serial CT scans, determined the earliest scan showing lung cancer, and evaluated the tumor shape, size, density, and location. Delay in diagnosis was measured from the time of the earliest scan showing lung cancer and the subsequent clinical diagnosis. RESULTS: During the mean follow-up period of 4.1 years, CT scans were obtained eight times on average. The median tumor size at presentation was 11 mm, and at clinical diagnosis was 22 mm. The median delay in diagnosis was 409 days. Fifteen tumors (65.2%) were in the interface between normal and fibrotic lung cysts (honeycomb cysts, paraseptal emphysema, and traction bronchiolectasis), four were in the area of ground-glass opacity, and one was in the midst of honeycomb cysts. Twelve tumors were round or oval, eight tumors had an ill-defined stellate shape, and two had a bandlike shape. One tumor appeared as an area of ill-defined increased lung attenuation. CONCLUSION: Nearly one half of the tumors had a stellate or bandlike shape and were difficult to recognize as tumors initially. Most of the tumors were located at the interface between normal lung and fibrotic cysts; only rarely were tumors located in the midst of honeycomb cysts.

Drug-induced interstitial lung disease in molecular targeted therapies: high-resolution CT findings.

Drug-induced lung injury (DLI) comprises a wide variety of pathologies, each with a unique imaging pattern, so there are no characteristic imaging findings to establish diagnosis. When DLI is suspected, evaluation must exclude progression of underlying disease, infection, and mimicking diseases. Correct diagnosis requires integration of clinical information and radiologic, laboratory, and pathological findings when available. We describe the radiologic findings of DLI, the roles of the findings in the management of patients with DLI, and the limitations of radiologic diagnosis.

Honeycomb lung: history and current concepts.

OBJECTIVE: Originally used to describe the macroscopic appearance of various pathologic processes with multiple cysts, honeycomb lung is now the term used to describe endstage pulmonary fibrosis. The purpose of this article is to discuss the history and imaging of honeycomb lung. CONCLUSION: Honeycomb lung is considered one of the important CT findings in usual interstitial pneumonia. An additional challenge for radiologists is that different pathologic processes can mimic honeycomb lung. Therefore, a precise understanding of honeycomb lung is necessary.

Computed tomography findings of current nonspecific interstitial pneumonia based on the 2013 updated classification of idiopathic interstitial pneumonias: What is a characteristic of previously diagnosed nonspecific interstitial pneumonia excluded from the updated classification.

PURPOSE: To evaluate computed tomography (CT) findings of nonspecific interstitial pneumonia (NSIP) based on the current classification of idiopathic interstitial pneumonias (IIPs) and elucidate a characteristic of previously diagnosed NSIP excluded from the current classification. MATERIALS AND METHODS: The study included 74 patients with biopsy-proven NSIP (idiopathic NSIP [I-NSIP], 39 patients; NSIP associated with connective tissue disease [CTD-NSIP], 35 patients). Among patients who were compatible with the current classification of IIPs, 29 and 21 were categorized as having current I-NSIP and current CTD-NSIP, respectively. The remaining 24 patients were categorized as having previous I-NSIP or previous CTD-NSIP due to the primary pathologic diagnosis of cellular NSIP or associated findings of acute inflammatory changes. CT findings were evaluated and compared among the four groups. RESULTS: Current I-NSIP was indicated by ground-glass attenuation and reticulation with traction bronchiectasis/bronchiolectasis in predominantly peribronchovascular areas of the lower lung zone. The previous I-NSIP group tended to show broader airspace consolidation than the current I-NSIP group (p = 0.068). The previous CTD-NSIP group showed significantly broader airspace consolidation than the current I-NSIP group (p = 0.035). CONCLUSION: Broad airspace consolidation is a characteristic of previously diagnosed CTD-NSIP excluded from the current classification of IIPs.

Pleuroparenchymal fibroelastosis-like lesions in patients with interstitial pneumonia diagnosed by multidisciplinary discussion with surgical lung biopsy.

PURPOSE: The present study aimed to evaluate the significance of Pleuroparenchymal fibroelastosis (PPFE)-like lesions in predicting prognosis in patients with chronic interstitial pneumonia (IP). METHOD: The present study enrolled 207 patients with IP in whom surgical lung biopsy was performed. Among the patients enrolled in the present study, 77 had idiopathic pulmonary fibrosis (IPF), 15 had nonspecific interstitial pneumonia (NSIP), 13 had chronic hypersensitivity pneumonitis (CHP), 41 had connective tissue disease (CTD), three had PPFE, and 58 had unclassifiable diagnosis. The incidence, characteristics, and thickness of PPFE-like lesions were evaluated in each patient with IP. Additionally, the influence of PPFE-like lesions on the prognosis was also determined. RESULTS: Of 207 patients, 160 (77.3 %) showed PPFE-like lesions. The frequency of PPFE-like lesions was similar in patients with IPF, NSIP, CHP, CTD, and unclassifiable diagnosis (79.5 %, 79.5 %, 73.2 %, 65.9 %, and 81 %, respectively); however, PPFE-like lesions were present in all patients with PPFE (p = 0.42). Consequently, there was no significant difference in the characteristics of PPFE-like lesions among patients with all forms of IP, except PPFE. PPFE-like lesions were not a significant predictor of prognosis (hazard ratio [HR], 1.16; 95 % confidence interval [CI], 0.64-2.10, p = 0.62); however, patients with PPFE-like lesions under the aortic arch had significantly poorer prognoses (HR, 2.70; 95 % CI, 1.66-4.39, p < 0.001). For craniocaudal extent comparison, patients with IPF with PPFE-like lesions below the level of the carina had significantly poorer prognoses than those without PPFE-like lesions (p = 0.001, overall survival 53.1 and 80.6, respectively). CONCLUSION: PPFE-like lesions are common in patients with IP, and their characteristics were not significantly different among all forms of IP, except idiopathic PPFE. The broad extent of PPFE-like lesions is an important predictor of prognosis in patients with IPF.

High-resolution CT features distinguishing usual interstitial pneumonia pattern in chronic hypersensitivity pneumonitis from those with idiopathic pulmonary fibrosis.

PURPOSE: Radiologic diagnosis of chronic hypersensitivity pneumonitis (CHP) presenting a usual interstitial pneumonia (UIP) pattern is challenging. The aim of this study was to identify the high-resolution CT (HRCT) findings which are useful to discriminate CHP-UIP from idiopathic pulmonary fibrosis (IPF). MATERIALS AND METHODS: This study included 49 patients with well-established bird-related CHP-UIP, histologically confirmed, and 49 patients with IPF. Two groups of observers independently assessed HRCT, evaluated the extent of each abnormal HRCT finding. When their radiological diagnosis was CHP-UIP, they noted the HRCT findings inconsistent with IPF. RESULTS: Correct CT diagnoses were made in 79% of CHP-UIP and 53% of IPF. Although no apparent difference was seen in the extent of each HRCT finding, upper or mid-lung predominance, extensive ground-glass abnormality, and profuse micronodules were more frequently pointed out as inconsistent findings in CHP-UIP than IPF (p = 0.007, 0.010, 0.001, respectively). On regression analysis, profuse micronodules [OR 13.34 (2.85-62.37); p = 0.001] and upper or mid-lung predominance of findings [OR 2.86 (1.16-7.01); p = 0.022] remained as variables in the equation. CONCLUSION: In this cohort, some IPF cases were misdiagnosed as CHP-UIP. Profuse micronodules and upper or mid-lung predominance are important clues for the differentiation of CHP-UIP from IPF.

Computed tomography findings in pathological usual interstitial pneumonia: relationship to survival.

RATIONALE: Patients with a clinicopathological diagnosis of idiopathic pulmonary fibrosis (IPF) may have typical findings of usual interstitial pneumonia (UIP) on computed tomography (CT) or nonspecific or atypical findings, including those often seen in nonspecific interstitial pneumonia. OBJECTIVES: The aims of this study were to revisit the high-resolution CT findings of IPF and to clarify the correlation between the CT findings and mortality. METHODS: The study included 98 patients with a histologic diagnosis of UIP and a clinical diagnosis of IPF. Two observers evaluated the CT findings independently and classified each case into one of the following three categories: (1) definite UIP, (2) consistent with UIP, or (3) suggestive of alternative diagnosis. The correlation between the CT categories and mortality was evaluated using the Kaplan-Meier method and the log-rank test, as well as Cox proportional hazards regression models. MEASUREMENTS AND MAIN RESULTS: Thirty-three of the 98 CT scans were classified as definite UIP, 36 as consistent with UIP, 29 as suggestive of an alternative diagnosis. The mean survival was 45.7, 57.9, and 76.9 months, respectively. There was no significant difference in survival among the three categories (all P > 0.05). Traction bronchiectasis and fibrosis scores were significant predictors of outcome (hazard ratios: 1.30 and 1.10, respectively; 95% confidence intervals: 1.18-14.2 and 1.03-1.19, respectively). CONCLUSIONS: In patients with IPF and UIP pattern on the biopsy, the pattern of abnormality on thin-section CT, whether characteristic of UIP or suggestive of alternative diagnosis, does not influence prognosis. Prognosis is influenced by traction bronchiectasis and fibrosis scores.

Aortic CT angiography using the double region of interest timing bolus technique: feasibility of 80 kVp scanning in lean patients.

To investigate the feasibility of aortic computed tomography angiography (CTA) performed at 80 kVp in lean patients using the double region of interest timing bolus (DRTB) technique compared to 100 kVp scanning. This study was approved by the institutional ethics committee, and all patients provided written informed consent. We prospectively included 165 patients from July 2018 to February 2019. We used an 80 kVp protocol when the maximal tube current did not exceed the limit using automatic exposure control; otherwise, 100 kVp was selected. The scan parameters for aortic CTA were determined from the test scan data. Enhancement at six points of the aortoiliac arteries and noise at the bifurcation level were measured. We compared the enhancement and signal to noise ratio (SNR) using Student's t-test. The tube voltage was 80 kVp in 87 patients (53%). The enhancement of the aortoiliac arteries was significantly higher (449.3 ± 77.8 vs 378.7 ± 53.1 HU, p < 0.0001) and the SNR was similar (42.4 ± 11.1 vs 40.0 ± 10.6, p = 0.17), and the amount of contrast medium was lower (33.0 ± 2.5 vs 41.8 ± 3.3 ml, p < 0.001) in the 80 kVp group compared to the 100 kVp group. Reducing the tube current to 80 kVp could decrease the amount of contrast medium used compared to the 100 kVp protocol, while maintaining image quality, for aortic CTA using the DRTB technique.

Inter-observer agreement in identifying traction bronchiectasis on computed tomography: its improvement with the use of the additional criteria for chronic fibrosing interstitial pneumonia.

PURPOSE: To assess inter-observer variability in identifying traction bronchiectasis on computed tomography (CT) using additional criteria for chronic fibrosing interstitial pneumonia. METHODS: Seven experts categorized CT image set representing 39 patients into three groups on the basis of the presence of traction bronchiectasis, using a three-point scale: 3-definitely/probably yes; 2-possibly yes; and 1-definitely/probably no. This scale served as a reference standard. The image set included cases of chronic fibrosing interstitial pneumonia, non-interstitial lung disease, and difficult-to-determine cases. Forty-eight observers similarly assessed the same image set, first according to the Fleischner Society definition, and second with additional criteria, in which traction bronchiectasis was observed exclusively in chronic fibrosing interstitial pneumonia. The agreement level between the reference standard and each observer's evaluation in each session was calculated using weighted kappa values which were compared between the two sessions using a paired t test. RESULTS: The mean weighted kappa value for all observers was significantly higher in the second reading session (mean 0.75) than in the first reading session (mean 0.62) (p < 0.001). CONCLUSION: Inter-observer agreement in identifying traction bronchiectasis improves when using the additional criteria which specify chronic fibrosing interstitial pneumonia as the underlying disease.

Progression from near-normal to end-stage lungs in chronic interstitial pneumonia related to silica exposure: long-term CT observations.

OBJECTIVE: The objective of our study was to evaluate serial CT changes from normal or near-normal lungs to honeycomb lungs in dust-exposed patients who developed chronic interstitial pneumonia. MATERIALS AND METHODS: From the records of the national hospital for pneumoconiosis, we retrospectively identified patients with chronic interstitial pneumonia who were under surveillance between 1986 and 2006. All patients occasionally underwent chest CT for evaluation of silicosis or exclusion of possible complications. Patients were included in this study only if the initial CT examination did not show obvious chronic interstitial pneumonia. Fourteen patients (all men; median age at initial CT, 58 years) were identified as meeting the inclusion criterion. Two independent reviewers randomly reviewed the CT scans of the study patients to score the extent of ground-glass opacity, reticulation, and honeycombing; to provide a summation of all interstitial opacities (fibrosis score); and to assess coarseness. RESULTS: Autopsy findings were available for eight of the 14 patients and confirmed the usual interstitial pneumonia (UIP) pattern seen on CT. The median follow-up period was 15.4 years, and none of the patients experienced acute exacerbation. One hundred two CT scans were reviewed. The earliest CT abnormalities included faint ground-glass opacity limited to the lung bases (n = 13) or only coarse reticular opacity (n = 1). In 13 patients, fibrosis and coarseness progressed linearly, whereas the other opacities did not. The annual increase of the fibrosis score and coarseness ranged from 0.306% to 4.633% and 0.179 to 0.479, respectively. Honeycombing developed in all patients over a median period of 12.1 years (range, 3.7-19.1 years). CONCLUSION: The coarseness best represented the progression of chronic interstitial pneumonia in dust-exposed patients. The earliest CT finding of a UIP pattern in dust-exposed patients was indistinguishable from other types of chronic interstitial pneumonia.

Acute eosinophilic pneumonia: Thin-section CT findings in 29 patients.

PURPOSE: To determine thin-section computed tomography (CT) characteristics of acute eosinophilic pneumonia (AEP). MATERIALS AND METHODS: Thin-section CT scans of 29 patients (14 males, 15 females; mean age, 26+/-15 years; age range, 15-72 years) with AEP were included this retrospective study. The clinical diagnosis of AEP was established by Allen's criteria. Each thin-section CT was reviewed by two observers. RESULTS: Bilateral areas with ground-glass attenuation were observed on thin-section CT in all patients. Areas of air-space consolidation were present in 16 (55%) of 29 patients. Poorly defined centrilobular nodules were present in 9 patients (31%). Interlobular septal thickening was present in 26 patients (90%). Thickening of bronchovascular bundles was present in 19 patients (66%). Pleural effusions were present in 23 patients (79%) (bilateral=22, right side=1, left side=0). The predominant overall anatomic distribution was central in only 2 (7%) of 29 patients, peripheral in 9 patients (31%), and random in 18 patients (62%). The overall zonal predominance was upper in 4 patients (14%), lower in 8 patients (28%), and random in 17 patients (58%). CONCLUSION: CT findings in AEP patients consisted mainly of bilateral areas of ground-glass attenuation, interlobular septal thickening, thickening of bronchovascular bundles, and the presence of a pleural effusion without cardiomegaly. The most common overall anatomic distribution and zonal predominance of the abnormal CT findings were random.

Low-dose chest computed tomography screening of subjects exposed to asbestos.

OBJECTIVES: The primary aim was to reveal the prevalence of lung cancer (LC) and malignant pleural mesothelioma (MPM) in subjects with past asbestos exposure (AE). We also examined pulmonary or pleural changes correlated with the development of LC. MATERIALS AND METHODS: This was a prospective, multicenter, cross-sectional study. There were 2132 subjects enrolled between 2010 and 2012. They included 96.2% men and 3.8% women, with a mean age of 76.1 years; 78.8% former or current smokers; and 21.2% never smokers. We screened subjects using low-dose computed tomography (CT). The CT images were taken with a CT dose Index of 2.7 mGy. The evaluated CT findings included subpleural curvilinear shadow/subpleural dots, ground glass opacity or interlobular reticular opacity, traction bronchiectasia, honeycombing change, parenchymal band, emphysema changes, pleural effusion, diffuse pleural thickening, rounded atelectasis, pleural plaques (PQs), and tumor formation. RESULTS: The PQs were detected in most of subjects (89.4%) and emphysema changes were seen in 46.0%. Fibrotic changes were detected in 565 cases (26.5%). A pathological diagnosis of LC was confirmed in 45 cases (2.1%) and MPM was confirmed in 7 cases (0.3%). The prevalence of LC was 2.5% in patients with a smoking history, which was significantly higher than that in never smokers (0.7%, p = 0.027). The prevalence of LC was 2.8% in subjects with emphysema changes, which was higher than that of subjects without those findings (1.6%); although, the difference was not statistically significant (p = 0.056). The prevalence of LC in subjects with both fibrotic plus emphysema changes was 4.0%, which was significantly higher than that of subjects with neither of those findings (1.8%, p = 0.011). Logistic regression analysis revealed smoking history, fibrotic plus emphysema changes, and pleural effusion as significant explanatory variables. CONCLUSIONS: Smoking history, fibrotic plus emphysema changes, and pleural effusion were correlated with the prevalence of LC.

A Volumetric Computed Tomography Analysis of the Normal Lung in Idiopathic Pulmonary Fibrosis: The Relationship with the Survival.

Objective An image analysis of high-resolution computed tomography (HRCT) can provide objective quantitation of the disease status in idiopathic pulmonary fibrosis (IPF). However, to our knowledge, no reports have investigated the utility of the normal lung volume for evaluating mortality from IPF. This study aimed to evaluate the relationship between the normally attenuated lung volume on HRCT as a percentage of whole-lung volume (NL%) and IPF mortality. Methods The NL% was determined by HRCT (between -950 and -701 Hounsfield units) using a density mask technique and volumetric software. The NL%, visual assessments of the normal lung by two radiologists, pulmonary function variables, and the gender, age, and physiology (GAP) index were retrospectively evaluated for 175 patients with IPF. Uni- and multivariate Cox proportional hazards analyses and C statistics for mortality were performed. Results The univariate Cox proportional hazards analysis identified the NL% as a prognostic factor [hazard ratio, 0.949; 95% confidence interval (CI), 0.936-0.964; p<0.0001]. In the multivariate analysis, the NL% was a prognostic factor, but the radiologists' visual assessment scores of normal lung were not. The C index increased when the NL% was included in the models of the pulmonary function variables. Furthermore, the C index for a combined model of GAP stage and categorized NL% (0.758; 95% CI, 0.751-0.762) was higher than for the model with the GAP stage alone (0.689; 95% CI, 0.672-0.709). Conclusion The NL% was a prognostic factor in our study population. Quantification of the normal lung using our method may help improve the IPF staging systems.