The classification for pneumoconiosis which was developed by International Labour Office(ILO) on the basis of Radiological findings of simple chest radiography has been widely used for the study and diagnosis of pneumoconiosis. But many problems have been revealed during the pneumoconiosis study using this classification. Those problems come from simple radiography itself or classification systems. Among those, inter-reader and intra-reader variability are the severest problems, even though many efforts have been devoted to lessen the variability. With introduction of computed tomography (conventional CT and HRCT), we are learning many new aspects about the occupational lung diseases, especially pneumoconiosis. So the studies for pneumoconiosis using tomography are reviewed, focusing on silicosis, coalworkers' pneumoconiosis, and asbestosis. But in our country, the studies of that kind are very scant. It is necessary to study and diagnose pneumoconiosis by CT, because that is the need of workers and the responsibility of physicians working in the field of occupational medicine. CT is superior to simple radiography in early detection, determination of severity, and follow-up of pneumoconiosis. But simple radiography is and should be the main method for the study and diagnosis of pneumoconiosis. Although, because of radiation hazard, cost, time, and geographical availability, the method can not and should not be used on the routine basis, we have to consider the use of CT, if possible and if necessary. Before using CT widely, we should develop the standardized criteria regarding to scanning methods and reading criteria. If not, the same problems as those of simple radiography will be occurred, and then there will be no progress in occupational medicine and workers' health.
Asbestosis ; Classification ; Diagnosis* ; Follow-Up Studies ; Learning ; Lung Diseases ; Occupational Medicine ; Pneumoconiosis* ; Radiography* ; Silicosis ; Thorax

A 70-yr-old woman visited our hospital for shortness of breath. Chest CT showed ground glass opacity and traction bronchiectasis at right middle, lower lobe and left lingular division. Video-assisted thoracic surgical biopsy at right lower lobe and pathologic examination revealed mixed dust pneumoconiosis. Polarized optical microscopy showed lung lesions were consisted of silica and carbon materials. She was a housewife and never been exposed to silica dusts occupationally. She has taken freshwater snails as a health-promoting food for 40 yr and ground shell powder was piled up on her backyard where she spent day-time. Energy dispersive X-ray spectroscopy of snail shell and scanning electron microscopy with energy dispersive x-ray spectroscopy of lung lesion revealed that silica occupies important portion. Herein, we report the first known case of silicosis due to chronic inhalation of shell powder of freshwater snail.
Aged ; Animals ; Carbon/chemistry ; *Dust ; Female ; Humans ; *Inhalation ; Silicon Dioxide/chemistry ; Silicosis/*diagnosis/radiography ; Snails/*chemistry ; Spectrometry, X-Ray Emission ; Tomography, X-Ray Computed

Diffuse pulmonary nodular lesions have many causes. When they are caused by infection, the likely organisms are M. tuberculosis and various fungi. Silicosis, eosinophilic granuloma and pulmonary metastasis should be considered for differential diagnosis. Differential diagnosis needs detailed clinical history, physical examination and various laboratory tests. A case of persistent diffuse pulmonary nodular lesions which had persisted 5 years is reported. The patient was a 25 years old man with minimal pulmonary symptoms. Detailed past history and physical examination suggested thyroid tumor. Chest radiography showed numerous evenly sized well-defined nodules scattered in entire lung fields. Previous chest X-rays showed similar nodular lesions, which had lasted for 5 years. The number of nodules was slightly increased. Neck CT showed heterogenous mass in left lobe of thyroid gland and multiple lymphadenopathies along both internal jugular chains. Total thyroidectomy was performed. A case of lung metastasis which progressed slowly in papillary thyroid cancer is reported.
Diagnosis, Differential ; Eosinophilic Granuloma ; Fungi ; Humans ; Lung ; Neck ; Neoplasm Metastasis ; Physical Examination ; Radiography ; Silicosis ; Thorax ; Thyroid Gland ; Thyroid Neoplasms ; Thyroidectomy ; Tuberculosis

Silicosis had been considered for decades as an illness with manifestations of lung fibrosis due to inhalation of overconcentrated SiO2 dust. To the best of our knowledge, studies have yet to report SiO2 deposits in any other tissues and organs. In the present case, while performing bilateral artificial total hip arthroplasty for one patient, we found that the articular cartilage of the bilateral femoral head was black. Therefore, specimens thereof were sent for pathological examination. Pathological examination (immunohistochemistry) and polarized light microscopy revealed the presence of considerable brown, acicular, rhombic, and crumb-like crystals. The crystals were mainly composed of SiO2. SiO2 could deposit in vessels and femoral head cartilage via blood circulation.
Blood Vessels/*chemistry ; Cartilage/*chemistry ; Femur Head/*pathology ; Humans ; Lung/*radiography ; Male ; Middle Aged ; Silicon Dioxide/*analysis ; Silicosis/*diagnosis ; Synovitis/*pathology

OBJECTIVETo study the character of welder's pneumoconiosis on CT, pathology, and lung function.

METHODSTo contrast 185 welder's pneumoconiosis and 115 silicosis on CT, pathology, and clinical characters which were diagnosed between Jan 2008 and Dec 2013. Chest X-ray and lung function of 39 welder's pneumoconiosis patients were followed up after diagnosed 4~6 years later.

RESULTSAverage age and working years of welder's pneumoconiosis were 36.7 and 11.5, less than silicosis patients 58.8 and 22.1, respectively (P<0.05). Of all 185 welder's pneumoconiosis 98.4% were of stage I and no stage III, while in silicosis group stage I, stage II and stage III were 56.5%, 22.6% and 20.9%, respectively. The ratio differences between the two groups were statistically significant,P<0.05. 82.7% of welder's pneumoconiosis patients were observed pathologically moderate or above dust deposition in lung tissue while interstitial fibrosis level was just mild (97.6% patients) or no fibrosis (2.4% patients). By contrast, 60.0% silicosis patients pathologically showed moderate or above dust deposition while 77.8% were of moderate or above fibrosis. CT findings in welder' s pneumoconiosis were diffuse branching linear structure (38.9%), low density consistent size centrilobular micronodules (19.5%), or both (30.8%). Poorly-defined ground-glass attenuation centrilobular micronodules or widely ground glass shadow were observed in 6.4% welder's pneumoconiosis patents. 30.8% patients failed to reach the original stage when 39 welder's pneumoconiosis followed up chest radiograph.

CONCLUSIONChanges in welder's lung caused by welding fume were not only siderosis, but also interstitial fibrosis.

Adult ; Dust ; Fibrosis ; Follow-Up Studies ; Glass ; Humans ; Lung ; pathology ; Middle Aged ; Pneumoconiosis ; physiopathology ; Radiography, Thoracic ; Siderosis ; physiopathology ; Silicosis ; diagnosis ; physiopathology ; Welding