Document MGjqY2E49aObjMqbBgeL9Lj7j

^ ' 3 i ,,` i i5 ' f- 216 WILI1AM V L0R1MER ET AL The relationship between pulmonary function signs of restriction and abnormal x rays was investigated No significant association was found (Table X) Chest x ray I he chest x rays were read twice by consensus reading, using at least three experienced readers, and categorized according to the ILO/U/C classification An x ray was read as abnormal if fine or moderately thm, irregular linear opacities were present (s or t > 1/0) and/or pleural thickening was present (a 1 or more) The prevalence of abnormal readings is given m Table XI Parenchymal abnormalities were present in 19 instances, nine 1/0, six 1/1, two 1/2 and two 2/2 X ray findings consistent with asbestosis increased with time, such a trend is evident in Table XII This trend is statistically significant TABLE X Relationship between X Ray Reading and Pulmonary Function Tests m 87 Vehicular i Maintenance Workers Pulmonary function Number of Subjects X ray reading Percent Restriction Obstruction Normal 25 Abnormal* 5 20% Normal 20 80% 43 Abnormal* 15 35% Normal 28 65% 30 Abnormal* 8 27% Normal 22 73% 4 parenchvinat fibrosis and/or pleural thickening For overall pattern X* = 1 78 50>p>30 For restriction alone X* = 1 21 30>p> 20 For obstruction alone X* -* 1 50 30>p>20 For obstruction and restriction compared to normal X* - 08 80 > p > 70 TABLE XI X Ray Changes in 90 Vehicular Maintenance Workers with over 10 Years' Experience Number Percent Parenchymal fibrosis Pleural thickening or calcification Both parenchymal and pleural changes Any changes ` 18 5 1 24 20% 6% 1% 27% TABLE XH X Ray of Vehicular Maintenance Workers by Year of Onset p/ Work .............................--Jr..................................A --............................................t............................. .1-- w--._1 f Abnormal4 ; 1956-65 1M6-55 Before 1946 Vea No Yes J No Yes > } No 3 08%) _14 " 10 , (23%) ' ' 33 ' r 14 (47%) - --------- ---------------- ............................................. - - --- .... -------------^ ,-r. ( r' i * Parertcfiyinol'fibrosis (1LO/UC s, t >4/0) and/nr pteufaj thickening's ~ V X* for before (956 compared With 1966 and after X' ^ &,9& t 02y> p >"Q1 16 1 '' - 5 "v i f\ ^ > i