IIRC, you're a radiologist. Can you differentiate asbestosis from silicosis with normal chest X-ray projections? How about CT scans?
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It is helpful to not only know what a disease looks like on imaging but why.
Silica dust is composed of crystalline particles. When you inhale them, the smaller ones can be cleared out by the normal lung clearing mechanisms (mucous, ciliary action, etc.) but the larger ones are harder to cough up. The macrophages in the lungs then "swallow" them as they would any other invader except that, since they are rock, the macrophages can't digest them and they get a fatal case of "indigestion". When the macrophages die, they release all their enzymes leading to a local inflammatory reaction.
The X-Ray appearance in silicosis is therefore one of fibrosis of the lung interstitium in a nodular pattern with each tiny nodule representing a silica crystal that has done its damage. This can progress to more fibrosis and coalescing nodule.
In asbestos, we are dealing with a crystalline fiber. The fibers work their way out to the periphery of the lung and actually puncture through the outer lung pleural. Microscopically, imaging the lining of the pleura looking like velvet with the tiny velvet hairs being the asbestos fibers. When you breath in and out, these fibers are scratching the pleura of the inner chest wall.....with every breath.......for every hour, day, week and year for many years. Eventually, you get "plaques" on the pleura of your inner chest wall and disphragm that can calcify. Sometimes the irritation leads to cancer of that irritated pleura (mesothelioma) that is a nasty form of cancer. Such changes can take many years after exposure to develop.
So, asbestosis can be diagnosed easily by the calcified pleural plaques. Industrial medicine also has "B Readers" that are technicians who quantify the degree of fibrosis, plaques, etc. for the purpose of workman's comp cases.
Calcified pleural plaques and diaphragm calcifications are a "giveaway" for asbestosis but it must be remembered that lung fibrosis can occur with all sorts of insults to that lung, even after a bout of pneumonia. You show me a 60 year old chest X-Ray and I will show you something that does not look 100% right. So, it is easy for "Doctor Whores" to get together with shyster lawyers and claim all sorts of things and fool insurance companies. If you make thousands of small fake claims, it is cheaper for ther companies to pay out thousands of small settlements that to investigate every single one.
There will be a test on this tomorrow.....Open book. ;-)