数字X射线摄影在尘肺筛查中的应用研究

目的 本研究从影像质量、辐射剂量、优质片率与阳性检出率等方面对传统尘肺高千伏屏-片摄影（FSR）和数字X射线摄影（DR）的性能进行对比分析,为数字DR摄影技术取代传统高千伏摄影应用于尘肺筛查提供科学依据。方法 分别用传统高千伏FSR装置和数字DR装置拍摄对比度-细节模体,并对影像质量进行客观比较。选择来我院进行尘肺筛查人员120人,经本人同意,分别进行DR胸片摄影和高千伏摄影,依据《职业性尘肺病诊断标准》（中华人民共和国国家职业卫生标准GBZ 70-2015）附录C进行评片,对胸片质量进行比较分析。回顾性统计2014-2015年我院使用两种设备摄影的阳性率。结果 高千伏模体摄影和数字DR模体摄影的IQFinv分别为1.41和2.58;DR胸片组和高千伏胸片组的优片率分别为82.50%和68.83%,两组胸片质量之间差异有统计学意义而在尘肺筛查效率方面无区别。结论 在不增加辐射剂量的前提下,DR胸片的影像质量明显高于FSR胸片;但两者在诊断效能上却有很好的一致性,数字摄影可用于粉尘作业者的职业健康普查。     

Relationships (I) of International Classification of High-resolution Computed Tomography for Occupational and Environmental Respiratory Diseases with the ILO International Classification of Radiographs of Pneumoconioses for parenchymal abnormalities

The International Classification of High-resolution Computed Tomography (HRCT) for Occupational and Environmental Respiratory Diseases (ICOERD) has been developed for the screening, diagnosis, and epidemiological reporting of respiratory diseases caused by occupational hazards. This study aimed to establish a correlation between readings of HRCT (according to the ICOERD) and those of chest radiography (CXR) pneumoconiotic parenchymal opacities (according to the International Labor Organization Classification/International Classification of Radiographs of Pneumoconioses [ILO/ICRP]). Forty-six patients with and 28 controls without mineral dust exposure underwent posterior-anterior CXR and HRCT. We recorded all subjects’ exposure and smoking history. Experts independently read CXRs (using ILO/ICRP). Experts independently assessed HRCT using the ICOERD parenchymal abnormalities grades for well-defined rounded opacities (RO), linear and/or irregular opacities (IR), and emphysema (EM). The correlation between the ICOERD summed grades and ILO/ICRP profusions was evaluated using Spearman’s rank-order correlation. Twenty-three patients had small opacities on CXR. HRCT showed that 21 patients had RO; 20 patients, IR opacities; and 23 patients, EM. The correlation between ILO/ICRP profusions and the ICOERD grades was 0.844 for rounded opacities (p<0.01). ICOERD readings from HRCT scans correlated well with previously validated ILO/ICRP criteria. The ICOERD adequately detects pneumoconiotic micronodules and can be used for the interpretation of pneumoconiosis.     

Follow-up of asbestosis patients and predictors for radiographic progression

Objective: We followed a group of 85 Finnish asbestosis patients radiographically for an average of 6.5 (range 2–10) years to examine the progression of the disease and to assess possible explanations for the progression. Methods: The examinations included full-size chest radiographs and a blood specimen analysis. The radiographs were classified according to the 1980 International Labor Office (ILO) classification. Progression was accepted if the second or third radiography was estimated (in a side-by-side comparison) to have more profusion of small opacities qualitatively than the first, even if the radiographs were classified into the same profusion category. Results: In all, 38% of the patients showed progression during the follow-up period. The average progression of small opacities ranged from ILO 1/1 to ILO 2/2 (0.4 minor ILO categories/year). The asbestosis was progressive more often among the sprayers than among the insulators and asbestos factory workers [cross-tabulation, odds ratio (OR) 5.0, 95% confidence interval (95% CI) 1.2–20]. In the logistic regression model the ILO classification category at the beginning of the follow-up (OR 1.54; 95% CI 0.96–2.47), the fibronectin (OR 1.01; 95% CI 1.00–1.01) and angiotensin-converting enzyme (ACE; OR 1.10; 95% CI 1.00–1.20) levels, and the erythrocyte sedimentation rate (ESR; OR 1.05; 95% CI 1.00–1.10) were statistically associated with the radiographic progression of small opacities. Abnormalities of the pleura were found to progress more often among the patients with progressive parenchymal opacities. Conclusion: For the progression of small-opacity profusion the significant predictors in the logistic regression model were the ILO profusion category at the beginning of the follow-up period, the fibronectin level, the ACE value, and the ESR. The model correctly classified 94% of the patients with progression and 65% of those without progression. The differences in the mean values recorded for the biomarkers between the progressors and nonprogressors, however, were small and may therefore not be of any importance to the clinician. Received: 17 November 1997 / Accepted: 8 May 1998     

Radiographic (ILO) readings predict arterial oxygen desaturation during exercise in subjects with asbestosis

Background: Exercise impairment is common in subjects with asbestosis. Arterial oxygen desaturation during exercise is an important contributor to exercise limitation. The International Labour Office (ILO) classification of plain chest radiographs correlates with resting pulmonary function, but its value in predicting abnormal ventilatory responses to exercise, including desaturation, has not been explored. Aims: To determine in subjects with asbestosis (1) if radiographic profusion scores and the extent of small irregular shadows on plain chest radiographs correlate with resting lung function and abnormal ventilatory responses to exercise; and (2) if radiographic scores add value to resting lung function tests in predicting abnormal ventilatory responses to exercise. Methods: Thirty eight male subjects with asbestosis were included. Plain chest radiographs were read according to the ILO classification independently by three observers. All subjects underwent assessment of lung function and an incremental exercise test. Results: Profusion scores and number of affected zones correlated significantly with the percentage predicted values of single breath diffusing capacity (DLCO), forced vital capacity (FVC), and total lung capacity (TLC). Arterial oxygen desaturation occurred in 29% of the subjects. The severity of desaturation correlated significantly with profusion and the number of affected zones. The combined use of number of affected zones, FEV₁/FVC ratio and DLCO predicted desaturation during exercise with an explained variance of 41%. VO₂max was significantly related only to DLCO but was not predicted by the ILO score. Conclusion: Arterial oxygen desaturation correlated with the profusion and extent of parenchymal abnormality on chest radiographs. The addition of morphological indices to physiological measurements is valuable for predicting oxygen desaturation during exercise but not for VO₂max. Refinement of the radiographic scoring system and the addition of more sophisticated imaging techniques may further improve the predictive power.     

Utility of digital radiography for the screening of pneumoconiosis as compared to analog radiography: radiation dose, image quality, and pneumoconiosis classification

The purpose of this study was to compare digital radiography (DR) and analog radiography (AR) for the screening of pneumoconiosis with respect to radiation dose, image quality, and pneumoconiosis classification. DR was performed on 50 subjects who were enrolled for an examination of pneumoconiosis (Digital Diagnost?, Philips, Netherlands), and AR (MXO-15B, Toshiba, Japan) was performed the same day after the study was approved by the Institutional Review Board and written informed consent was obtained from all subjects. Entrance surface doses (ESDs) of DR and AR were measured using a glass dosimeter attached to a Rando human phantom (Alderson Co., U.S.) under exposure conditions commonly used in clinical practice in Korea. Visibilities on all images were evaluated using a 5-point scale by four chest radiologists using a modified form of the European Chest Guidelines (EUR 16260). All the images were classified using the ILO's guidelines by referencing standard analog radiographs. ESDs of DR were significantly lower than those of AR (0.15 mGy vs. 0.21 mGy, p < 0.05). All anatomic structures were significantly more visible by DR images (p < 0.0001), especially the left main bronchus, ribs, and thoracic spine. Body mass index did not correlate with anatomic structure visibility by DR (r = -0.029, p = 0.842) or AR images (r = -0.076, p = 0.602). Overall intra- and inter-reader agreements for DR images were significantly higher than for AR images. DR offers improved image quality with a significant reduction of up to 23.6% in radiation dose and more accurate pneumoconiosis classification than AR.     

计算机X线摄影与传统X线新生儿胸部床片摄影的对比

目的:比较计算机X线摄影(CR)与传统X线摄影两者在重症新生儿胸部床片摄影中的应用价值,保证CR的图像质量,提高新生儿胸部床边摄片优质片比例。并与传统X线新生儿床片摄影的对比。方法:回顾性分析我院重症新生儿CR床片胸片和常规床片胸片各500张年龄0~28天的婴幼儿,经集体读片将其评估分为Ⅰ~Ⅳ级,提出优质片评估标准。结果:CR胸片:Ⅰ级片(优)470张、Ⅱ级片(良)20张、Ⅲ级片(差)6张、Ⅳ级片(废)4张,常规胸片:Ⅰ级片(优)238张、Ⅱ级片(良)206张、Ⅲ级片(差)32张、Ⅳ级片(废)24张,统计学比较X2=77.45,p<0.01,差别显著。曝光剂量约降低一半。经CR系统后处理调节后与屏/胶片系统进行对照。结论:CR系统在婴幼儿胸部摄影中的应用实现了影像数字化,降低了X线照射剂量,提高了影像质量,基本消除了废片,为临床提供了良好的影像诊断依据。     

Observer variation in classifying chest radiographs for small lung opacities and pleural abnormalities in a population sample

Background The purpose of this study was to assess inter- and intraobserver variation in the radiographic categories of small lung opacities (profusion) and pleural abnormalities classified according to the ILO classification of pneumoconioses with some modifications. Methods Chest radiographs derived from a representative adult population sample (n = 7,095) were classified by two radiologists. Observer variation was assessed on the basis of kappa (κ)-type statistics. Results The observers agreed on profusion categories in 69% of cases of the total material. Up to 98% of the classifications fell into the same category or deviated by no more than one category. The corresponding kappa (κ) coefficient was 0.48 (95%CI = 0.46–0.49) and the weighted κ 0.72. When a selected subsample was reclassified by the observers, the proportions of crude agreement on profusion of small opacities ranged from 42% to 47% (weighted κ 0.52–0.55). The proportions of agreement on the main pleural abnormalities were 92% or over, and the corresponding κ coefficients at least 0.73. Conclusion The classification of lung opacities was subject to considerable observer variation, which calls for caution when results from different studies are compared. This variation, however, rarely exceeded one category, and thus appears to be small enough for meaningful comparisons between groups, at least within a single study. Am. J. Ind. Med. 34:261–265, 1998. © 1998 Wiley-Liss, Inc.     

粉尘作业者肺部小阴影的高千伏胸片与高分辨率CT对比研究

[目的]比较高分辨率CT(HRCT)和高千伏胸片对粉尘接触者肺部小阴影的显示能力。[方法]对137例(男性125例,女性12例)HRCT和高千伏胸片资料完整者的影像学资料进行回顾性分析。其中,接触焊尘者56例,接触矽尘者37例,接触其他粉尘(包括铝尘、炭黑、水泥等)者44例。HRCT采用2mm层厚、10mm间隔从肺尖至膈肌扫描,采用-700HU/1500HU的窗位/窗宽进行摄片和观察。HRCT和高千伏胸片在不知晓职业史的前提下分别进行读片。对胸片和HRCT评估获得的各肺区小阴影的密集度进行一一比较,并对小阴影总体密集度进行比较。[结果]HRCT对小阴影总体密集度的评估与胸片评估密切相关(r=0.655,P<0.01),但HRCT对小阴影的评估分辨率高于胸片(P<0.01)。115例HRCT显示小阴影,其中s影86例,p影5例,p/s影8例,s/p影15例,q影1例。86例胸片显示小阴影,其中s影25例,p影5例,p/s影28例,s/p影24例,q/p影3例,q/s影2例。86例胸片显示小阴影的工人中6例HRCT显示正常。50例胸片无小阴影的工人中,34例(68%)HRCT显示异常小阴影。HRCT显示了上肺区及背部小阴影的分布优势。[结论]胸部HRCT在小阴影早期检测方面可弥补胸片的不足,对于准确评估小阴影有一定价值。     

Chest x ray films from construction workers: International Labour Office (ILO 1980) classification compared with routine readings.

The extent of agreement between International Labour Office (ILO) and clinical readings of chest x ray films from construction workers was studied. From a survey of 5898 workers 258 subjects with a profusion of small opacities of > or = 1/1 and a stratified sample of subjects with profusion < 1/1 were selected. Only 41% of the films classified as ILO profusion category > or = 1/1 were clinically recorded as non-normal for the parenchyma. The proportion of films recorded as pneumoconiotic (or possibly so) was especially low for irregular opacities (22%), but increased with the profusion category (both rounded and irregular) as well as with the size of rounded opacities (p 3/11, q 12/25, r 3/4). Only with the profusion category > or = 2/1 were most of the films recorded as pneumoconiotic. The specificity and sensitivity were highest in the geographical areas where a few clinical readers had assessed many films each. The proportion of false negative clinical reports was low for circumscribed pleural thickening of the chest wall (9%) and diaphragmatic pleural thickening (6%). For calcified pleural changes and for the combination of diffuse pleural thickening and obliteration of the costophrenic angle, false negative reports were absent. The present study shows an unsatisfactory sensitivity for clinical compared with ILO readings as a means for screening the parenchyma of workers with a risk of pneumoconiosis.     

Chest x ray films from construction workers: International Labour Office (ILO 1980) classification compared with routine readings.

The extent of agreement between International Labour Office (ILO) and clinical readings of chest x ray films from construction workers was studied. From a survey of 5898 workers 258 subjects with a profusion of small opacities of > or = 1/1 and a stratified sample of subjects with profusion < 1/1 were selected. Only 41% of the films classified as ILO profusion category > or = 1/1 were clinically recorded as non-normal for the parenchyma. The proportion of films recorded as pneumoconiotic (or possibly so) was especially low for irregular opacities (22%), but increased with the profusion category (both rounded and irregular) as well as with the size of rounded opacities (p 3/11, q 12/25, r 3/4). Only with the profusion category > or = 2/1 were most of the films recorded as pneumoconiotic. The specificity and sensitivity were highest in the geographical areas where a few clinical readers had assessed many films each. The proportion of false negative clinical reports was low for circumscribed pleural thickening of the chest wall (9%) and diaphragmatic pleural thickening (6%). For calcified pleural changes and for the combination of diffuse pleural thickening and obliteration of the costophrenic angle, false negative reports were absent. The present study shows an unsatisfactory sensitivity for clinical compared with ILO readings as a means for screening the parenchyma of workers with a risk of pneumoconiosis.     

尘肺诊断标准中小阴影密集度的应用价值

目的探讨尘肺诊断标准中小阴影密集度的应用价值。方法采用职业流行病学的方法,参照1980ILO国际尘肺X线影像分类指南,分析比较了太钢耐火厂不同时期接尘工人X线胸片小阴影密集度小级的发生率、发生密度及其与工龄的关系。同时,选择了接触煤矽尘工人的X线胸片与之比较其胸片小阴影密集度小级的发展速度和特点。结果①不同时期接尘工人胸片小阴影密集度小级的发生率不同,统计学检验P＜0．05。②胸片小阴影密集度随工龄延长而呈现出由低到高的上升趋势。③接触不同性质粉尘的工人其小阴影密集度小级的晋级速度不同。结论小阴影密集度是观察尘肺发生发展、评价生产环境的质量和估测接触粉尘性质的指标。     

Relations between occupational exposure to coal mine dusts,erythrocyte catalase and Cu++/Zn++ superoxide dismutase activities,and the severity of coal workers' pneumoconiosis

OBJECTIVES: To better understand the relations between occupational exposure, blood antioxidant enzyme activities, total plasma antioxidant concentration, and the severity of coal workers'' pneumoconiosis (CWP). METHODS: Blood samples were obtained from miners without CWP exposed to low dust concentrations for > or = 4 years at the time of the study (n = 105), or exposed to high dust concentrations for > or = 14 years at the time of the study (n = 58), and from retired miners with CWP (n = 19). Miners without CWP were classified into three subgroups according to their estimated cumulative exposure to dust. Chest x ray films were obtained for each miner. Miners were classified in five subgroups according to their International Labour Organisation (ILO) profusion grades. Univariate tests were completed by multiple linear regression analyses. RESULTS: The estimated cumulative exposure to dust was strongly positively related to erythrocyte catalase activity and strongly negatively related to Cu++/Zn++ SOD activity only in miners exposed to high dust concentrations for > or = 14 years at the time of the study (F tests p = 0.006 and p = 0.004 respectively). Moreover, catalase activity was strongly related to the severity of CWP expressed as five subgroups of ILO profusion grades (F test p = 0.003); the greatest difference in the mean values was found between the group of 1/1 to 1/2 ILO profusion grades and the group of 2/1 to 3/3 ILO profusion grades. CONCLUSION: These results are in good agreement with the hypothesis that production of reactive oxygen species may be an important event in the exposure to coal mine dusts and the severity of CWP. Erythrocyte catalase and Cu++/Zn++ SOD activities are more closely related to recent exposure to high dust concentrations than to cumulative exposure, and could be considered as biological markers of exposure rather than as markers of early adverse biological effect.       

Correlation between radiological and functional findings in workers exposed to chrysotile asbestos

The relationship between the extent of respiratory disease from chest radiographs and the severity of functional impairment was assessed in 185 workers with long-term exposure to asbestos in an asbestos-cement factory. The workers were divided into seven subgroups according to functional abnormality findings (restrictive, obstructive, mixed restrictive-obstructive, reduced diffusion capacity, increased diffusion capacity, small airway disease and normal). Restrictive functional abnormality was present in 29% of the workers, obstructive and mixed in 3% small airway disease in 4%, reduced diffusion capacity in 4% increased diffusion capacity in 7%, while the remaining 49% were normal. The subjects with radiological diffuse pleural disease were characterized by FVC reduction, whereas in those with mixed pleural-parenchymal radiological abnormalities both FVC and DLCO were reduced. FVC and DLCO decrements correlated well with the increasing grades of profusion according to the ILO classification. In the group of workers with normal chest radiographs and normal spirometry, a decrease or increase in lung diffusion capacity for CO (DLCO) was an isolated finding. In addition, a correlation existed between the length of exposure and functional parameters (reduced FVC and DLCO, while FEV1/FVC increased with longer exposure). The study shows that reduced lung function indices can be found in subjects without radiological evidence for parenchymal asbestosis (ILO grade 1/1 profusion or greater). The results suggest that asbestos exposure, in addition to lung diffusion capacity decrease, can be accompanied by an increase in lung diffusion capacity.     

Coalworkers' pneumoconiosis: correlation between opacity profusion and number and type of dust lesions with special reference to opacity type.

The relation between the profusion and predominant type of small rounded opacities on chest radiographs taken within four years of death and the postmortem counts of dust lesions in four classes (macules, "pinhead" fibrotic nodules, nodules 1-3 mm, and nodules greater than 3-9 mm in diameter) has been examined for 71 coalworkers without progressive massive fibrosis. The radiographs were categorised by four readers independently, according to the ILO classification. For subjects considered by each reader to present predominantly p type opacities, increasing opacity profusion was exclusively and significantly associated with an increase in the number of pinhead fibrotic nodules. Numbers of nodules measuring 1-3 mm and greater than 3-9 mm in diameter both showed significant linear associations with opacity profusion category in subjects presenting predominantly q opacities, the closer association being observed with the smaller lesions. These observations held true for all readers. Opacities of type r were rarely considered to be the predominant type. For the reader who recorded the maximum number of such cases, opacity profusion was not significantly related to the numbers of dust lesions in any of the lesion classes. Nevertheless, the closest association was observed with nodules measuring greater than 3-9 mm in diameter. An overall significant linear association between total lung dust content and opacity profusion was found to be due mainly to subjects presenting predominantly p type opacities and to a lesser extent to those with predominantly q opacities.     

Some factors influencing interobserver variation in classifying simple pneumoconiosis.

Three experienced physician readers assessed the chest radiographs of 743 men from a coal mining community in West Virginia for the signs of simple pneumoconiosis, using the ILO U/C 1971 Classification of Radiographs of the Pneumoconioses. The number of films categorised by each reader as showing evidence of simple pneumoconiosis varied from 63 (8.5%) to 114 (15.3%) of the 743 films classified. The effect of film quality and obesity on interobserver agreement was assessed by use of kappa-type analytic procedures for measuring agreement on categorical data. Poor film quality and obesity both affected agreement adversely. Poor quality films were disproportionately frequent in obese individuals, as defined by the Quetelet index. On control of film quality by stratification, the effect of obesity on interobserver profusion agreement was no longer evident.     

Some factors influencing interobserver variation in classifying simple pneumoconiosis

Three experienced physician readers assessed the chest radiographs of 743 men from a coal mining community in West Virginia for the signs of simple pneumoconiosis, using the ILO U/C 1971 Classification of Radiographs of the Pneumoconioses. The number of films categorised by each reader as showing evidence of simple pneumoconiosis varied from 63 (8.5%) to 114 (15.3%) of the 743 films classified. The effect of film quality and obesity on interobserver agreement was assessed by use of kappa-type analytic procedures for measuring agreement on categorical data. Poor film quality and obesity both affected agreement adversely. Poor quality films were disproportionately frequent in obese individuals, as defined by the Quetelet index. On control of film quality by stratification, the effect of obesity on interobserver profusion agreement was no longer evident.     

Digital chest radiography image quality assessment with dose reduction

A retrospective study of digital chest radiography was performed to compare the image quality and dose parameters from two X-ray rooms in different areas of the same hospital using identical X-ray units but different local protocol for obtaining chest PA and lateral radiographs. Image quality of radiographs was assessed from the printed films using well established European guidelines and modified criteria. Patient entrance surface air kerma was calculated using technical data recorded for each radiograph and measured output of the X-ray unit. Effective dose and dose to radiosensitive organs was estimated using dose calculation software PCXMC. There was no statistical significant difference in the evaluated image quality using either technique, median entrance surface air kerma to the patient reduced significantly with added filtration technique and use of normal density setting. Phantom measurements indicated that an additional filtration of 0.1 mm Cu + 1 mm Al in the X-ray beam alone reduced the entrance surface air kerma by 35%.     

Relation of spirometric function to radiographic interstitial fibrosis in two large workforces exposed to asbestos: an evaluation of the ILO profusion score.

OBJECTIVES: To analyse quantitatively the relations of spirometric lung function (forced vital capacity (FVC)) to radiographic interstitial pulmonary fibrosis (assessed by the International Labour Organisation (ILO) profusion score of small irregular opacities) in two large workforces exposed to different intensities of asbestos. These analyses consider the question whether a similar profusion score n differently exposed workers is associated with a similar effect on lung function. METHODS: Surveys of two workforces, insulators (n = 2611) and sheet metal workers (n = 1245), by the same investigators allowed comparison of the effects of the two levels of exposure to asbestos. The two groups were of similar age and had similar percentages of non-smokers and smokers. All radiographs were read by the same expert reader. RESULTS: Consistent with their less continuous and less intense exposure to asbestos, metal workers had: (a) far less frequent radiographic asbestosis (profusion score > or = 1/0, 17.5% v 59.6% for insulators): (b) less severe radiographic asbestosis (only 1.1% had scores > or = 2/1 v 13.3% of insulators); (c) a similar slope to that seen in insulators for the relation between FVC and profusion score when pleural thickening was absent; (d) less frequent pleural fibrosis (36% v 75%); and (e) less frequent restrictive impairment (23% v 33%). In both insulators and metal workers, lung function was below normal even when lung fields were normal, FVG fell with increasing profusion, it was lower in smokers and in those with pleural thickening at comparable profusion scores, and these was no difference in FVC between scores 0/1 and 1/0. CONCLUSION: The decrease in FVC with increasing profusion score in both workforces as well as the similar slopes for the relation between FVG and profusion score and the similar FVG at similar scores in the absence of pleural thickening confirm the ILO profusion score as an acceptable assessment of pulmonary fibrosis.     

International classification trial of AIA set of 100 radiographs of asbestos workers

A series of 100 full size radiographs illustrating the range of asbestos related radiographic changes was collected by the Asbestos International Association to provide a demonstration and teaching supplement to the ILO 1980 International Classification of the Radiographic Appearances of Pneumoconioses. Each film was read by 12 experienced readers from ten countries; the readings have been summarised by a median reading, with the range covered by two thirds of the readers. The occupational histories and some relevant clinical information are also available. It is proposed that, in the use of this set, readers should classify each film using the ILO classification rules, particularly without reference to the summary reading or the additional information. Comparing the individual readings by the 12 readers, most of the variation in reading the profusion of small opacities was ascribable only to random variation, with little consistent bias between readers. By contrast, two readers recorded pleural changes much more frequently than their colleagues. This illustrated a major problem with the ILO 1980 Classification. Several others which occurred in this reading trial are also discussed.