Document m2gjQ7pkBa7G1axeGe9VObGk

I 163.; Well, now, coming on from that -- next slide - we! j come to the beginning of what we call progressive, massive- j fibrosis, PKF, which the ILO calls pneumoconiosis, with coalescent massive shadows where, in addition to the general I condition, you have an area with larger opacities, amounting to rather more in diameter than appear, and although, in many films, the radiograph also shows a definite mass. That is the beginning wnich we call PMF, to distinguish the cate-* I .gories from the numbers wa use in simple pneumoconiosis. . j The next--slide. These cases have the peculiar ! jproperty that they tend to progress whether or not the man is exposed to further dust inhalation. Our simple pneumo coniosis, we see progression from Category One to Two or Two to Three only under conditions of dust exposure where ! j presumably further coal dusts are being laid down in the lung, but here is a radiograph of a'man who leaves with a shadow, leaving the mine in 1941* > Next slide. By 194-3* he has now a sizeable mass ! of it here and another one beginning there -- (next slide) ! i -- and in 194-7 he has a very definite mass here. ..'ote tne; I next one. The next one -- may we have the next one -- tnis ; t is 1947 with now a large mass in both'sides of the lung field, and we indicate these decreasing size of masses with the letters B and C, B for shadows that extend only over r.-'-l three anterior rib spaces, C if they extend over .-.ore '-.in SEVENTH SARANAC -0193