The Prevalence of Asbestos Related Pleural Plaque among Residents Living Near Asbestos Mines in Korea / 대한산업의학회지

OBJECTIVES: The investigation of the prevalence of pleural diseases in regards to those living within 1 km of 14 asbestos mines in Chungnam province. METHODS: We enrolled 4,057 residents (male: 1,887, female: 2,170) living within 1km of asbestos mines in Chungcheong province. They received checkups from Soonchunhyang Environmental Health Center for asbestos related diseases between March 2009 and December 2009. Chest X-rays were taken from all subjects and read by two experts according to International Labor Organization guidelines. Those subjects suspected of asbestos related lesions were further checked with HRCT(high-resolution computed tomography). The determination was done by two experts after reviewing the resulting data. RESULTS: The 4,057 exposed residents underwent the checkup, 859 of whom further underwent the HRCT(high-resolution computed tomography) check. The prevalence of pleural plaque was found to be 11.3% (29.2% non-occupational, 8.0% occupational) from the chest X-rays. The HRCT(high-resolution computed tomography) results revealed that 227 subjects (26.4%) out of the 859 positive subjects (110 (18.8%) non-occupational, 117 (42.9%) occupational) showed evidence of pleural plaque. The statistical analysis showed that the prevalence of pleural plaque increased with increases in age, residence time, and occupational family exposure to asbestos (p<0.05). CONCLUSIONS: We recommend better control of asbestos in the soil and mines. We also recommend that all affected residents living near asbestos mines receive medical checkups as mandated by the asbestos health damage relief policy.

Clinic Application of SCT Diagnosis for Pleural Plaque / 中国医学影像学杂志

Purpose To study the spiral CT (SCT) appearances of pleural plaques,to improve the accuracy of diagnosis and differential diagnosis,and to evaluate clinic application.Materials and Methods The SCT appearances in 42 cases with pleural plaques were analysed retrospectively,which closed met with asbestos dust.Results SCT showed 407 pleural plaques in 42 cases,of which there were hyline / uncalcified pleural plaques (n=250),calcified pleural plaques(n= 36),mixed pleural plaques(n=121);unilateral pleural plaques (n=10),bilateral pleural plaques (n=32);single pleural plaque in 5 cases,multiple pleural plaques in 37 cases.The largest pleural plaque was 4.2cm×1.2cm.There were a lot of shapes of the pleural plaques.Various shapes of calcifications could be showed in the calcified or mixed type pleural plaques.The pleural plaques distributed in the middle-inferior part,anterior / posterior-lateral chest wall,underlying the ribs in 28 cases (66.6 %),both bilateral domes of diaphragm in 10 cases and mediastinal pericardium in 4 cases.The pleural plaques associated with pulmonary intertitial fibrosis in 4 cases.No cases in the apices / costophrenic angles.No enhancement of pleural plaques in 6 cases which were administrated contrast scan.Conclusion SCT can clearly show the distribution,extention,shape,size,density and relation to adjacent tissues of the pleural plaques,and with asbestos exposure history,can make a diagnosis and differential diagnosis from other pleural thickened lesions.SCT is the best choice of imaging methods for asbestosis and pleural plaque.