Document wqbNMaNz5doRx761b8B5DNvm4

FILE NAME Brakes BRK DATE 1939 DOC BRK006 DOCUMENT DESCRIPTION Journal Article - Study of the Lungs of Workmen in the Asbestos Industry odagen dsies bke . ca CONTHLY JOURNAL JOURNAL DEVOTED TO CLINICAL RADIOLOGY AND ALLIED SCIENCES Volume 33 December 1939 Owned and Published by RADIOLOGICAL SOCIETY OFNORTH AMERICA As Its Official Journal Journal wv AN RAY STUDY OF THE LUNGS OF WORKMEN COVERING A PERIOD OF TEN IN THE ASBESTOS YEARS INDUSTRY ByARIALW. GEORGE GEORGE M.D. and RALPH D. LEONARD M.D. Boston Massachusetts D inhalation is a subject in which DDwe have been particularly interested for the past ten years Our approach cident boards and also as a disease con- dition in the individual its pathology tahend prognosis as observed by us through problem to this medium of the has been through the ray During the past five years the dust hazard in many in- ray In 1928 we began the intensive study of those exposed to the asbestos hazard in one of the large industrial plants in Massa- tor for the individualindividual workman workman asaswellas for the corporation and insurance com- pany In some instances the amount of alleged disability disability among the worknien from dust had reached such proportions that insurance companies became insolvent and the industrial plants were forced to close for lack of compensation insurance pro- tection chusetts where brake lining was manu- factured The hazard created was princi- pally asbestos with less than 30 per cent silica Dry weaving was first used and then changed to wer weaving This change was brought about by the fact that in 1928 and 1929 there were numerous cases which showed symptoms referable to the lungs characterized by increased difficulty in During this period we have had the op- portunity of studying the chesis of thousand three thousand workmen exposed to a regular hazard in their occupation groupincluded various types of dust over dust This haz- mining and manufacturing and from various parts of this country cast of the Rockies From this group it has been breathing on exertion cough sleeplessness and loss of weight Of all the cases we examin1e92d8 and 1929 our records show that in 12 cases ray examination revealed changes in the lungs upon which we based our diagnosis of asbestosis These 12 were at once put on compensation or given a lump settlement and have been under our privilege to observe with the ray the changes in the chest which may result from more or less continuous exposure to various types of dust such as silica tale marbie coal asbestos heavy metals such as iron and brass and various organic dusts such as wood ber In this rather cursory paper it is our to record our observations and purpose conclusions based on an ray study of one type dust of dust hazard namely asbestos The disease condition resulting from observation for seven years throwing con- siderable light on the natural progress of the disease From about 1928 to 1933 we routinely examined those cases sus- pected clinically of asbesrosis By 1933 the insurance premiums had pyramided to 15 per cent of the payroll and the carriers were rather indifferent to the taking on of this risk Finally that panies decided they this risk one of the large comthat before they took over would have examined clinically and by ray all of the cinployees the inhalation of asbestos dust is that form of peoconiosis known as asbestosis We shall comment on this disease as an economic problem surance companies as it concerns the and the industrial in ac- of the plant totaliing approximately eight hundred The majority of these workmen were examined by us immediately at the plant There was a very small number of the total employees whose conditions we diagnosed as asbestosis Out of this num Read oa part by invitation at the Twenty Annual Meeting Meeting of the Radiological Society of North America at Pittsburgh Nov. 28- Dec. 285 285 This one of a series of papers . tributed by friends and former pupils of I. Seth Hiach M.D. ber that we either suspected or diagnosed asbestosis there were three cases that were definitely advanced These three cases were of interest because they did not show 196 GEORGE AND LEONARD LUNGS IN ASBESTOS INDUSTRY 197 any of the usual clinical signs and would account of the high wages they are earning change their occupations hese three men continued to work until e plant was closed in 1936. One of the free became a litigant later The other vo disappeared into other industries and recorded re not claiming disability as claiming to disability ite A survey ofthis type naturally revealed wany interesting lung conditions aside om asbestosis such as aneurysm carly aled active and chronic tuberculosis tuberculosis cart abnormalities and many cases of sidual changes from previous lung dis- The plant was eventually eventually sold to a comtitive company and was immediately losed Within a short time after the clos- ng of the plant ) workmen brought in aims for disability due to asbestosis These 90 cases were examined by us by x- ay and we made a positive diagnosis of bestosis on 12 with three additional ases questionable About 13 per cent of The positive ray diagnoses in this group 90. claimed of asbestosis symptoms The insurance carrier for this competitive ompany imm^'diately placed these 12 sed either on compensation or they were ven lump settlement in excess of 50,00 The diagnosis was based upon he clinical and the ray examinations rincipally the ray There were left 78 uses claiming disability but their physical and ray examinations were negative evidence of this group of7s claiming disability ithout physical or ray but of sbestosis 30 came to trial There is in Aid Aid ar city the Legal Aid Society which arnishes able counsel for the plaintiffs as well as competent medical experts A very apable attorney was chosen for these ases and the late john B. Hawes Jr. I.D. as the medical expert He in turn samined thesethese cases both clinically and ray On these 30 cases he made a diagnosis Under our Statates of Industrial Diseases of the State of Massa- husetts is the called Panel Doctors \ group of three one of whom is a roent- genologist Under our State Law their diagnosis is final They had the opportunity to examine 10 of these 30 cases Their reports in no instance definitely stated asbestosis but their findings were reported as consistent with or a probability slight degree of or the of asbestosis It was obvious in reading their reports that they were not depending on ray findings alone but were giving the benefit of the doubt to the workmen in many instances being influenced by the history of exposure The ray films of these cases which were diagnosed as positive by the Panel Doctors we would have called negative This illustrates the great difficulty in interpreting an ray film as to the presence or absence of lung changes due to asbestosis In many instances it is a matter of personal opinion and the value of an opinion is in a large measure in proportion to the roentgenologist's training and experience in this specialized field The late John B. Hawes Jr. M.D. who was one of our distinguished specialists on expressed tuberculosis always forcefully his opinion regarding an individual who . worked in a dust hazard claiming that ex- posure for three years or more made the individual a potential case of asbestosis He so expressed himself when these cases came to trial We all felt that at least 80 per cent of his positive diagnoses depended upon history of exposure rather than sub- jective or objective physical signs attempt We will not in this paper to take up the question ofphysical diagnosis but we will say that it is our firm conviction diagnosis that at the present time the only method of positive diagnosis is the ray and that aside from the history of exposure there are no clinical pathognomonic signs of the disease The clinical facts on which Dr. Hawes based his diagnosis and prognosis of asbestosis were as follows 1 history of exposure 2 difficulty in breathing on exertion 3) cough 4 rapidity of heart action on exertion and 5 that asbestosis was a progressive disease once contracted whether the individual remained in the industry or was removed 198 RADIOLOGY In addition to these clinical observations of Dr. Hawes it is interesting to note that in our experience a large number of patients showing a definite ray evidence of asbestosis give a history of coughing up blood symptom of hemorrhage so commonly observed is due to small bronchial ulcers It has also been observed that asbestos dust like silica and some of the other dusts seems to have a selective action In other Fig 1 Fig 1 Case 1 Mrs. A. examined impartially in 1931 was negative employment from 1919 to 1929 from 1931 to 1934 Fig 2. Case 2. Mr. D. more than six years continuous exposure Fig 2 1936 positive Intermittent The amount of blood varies considerably usually no more than streaked sputum occasionally a substantial amount of pure blood We have speculated considerably as to the etiology of this symptom It has been observed for some time that workers in asbestos dust are prone to the development of areas of irritation on the hands In many instances these lesions develop into open ulcers which are extremely difficult to heal Microscopic examination of some of these ulcer bases has demonstrated the presence of asbestos fibers embedded in the deep layers of skin A total removal of the ulcerative tissue containingt he asbestos fibers results in prompt healing the lesion It is not inpossible that a somewhat similar condition may develop in the trachea or bronchi of the lungs with a superficial erosion of the mucous membrane due to the mechanical irritation of the asbestos fiber and the words certain individuals seem sensitive to the asbestos dust and others are immune Ita very common experience to find two individuals working in the same concentration of dust for the same length of time and same type of work and only one developing asbestosis the other remains in perfect health No satisfactory explanation has been made of this apparent idiosyncrasy It is possible that the explanation may be simple one namely the method of breath- ing The man who habitually breathes through his nose with all the protective mechanism which Nature has furnished to prevent dust hazard would have much less chance of developing injury to his lungs than the man who habitually breathes through his mouth and does not receive the benefit of the protective organs of the nose and nasal pharynx As a light on the question whether or not asbestosis is a progressive disease I Ah B She oe Vol 3 GEORGE AND LEONARD LUNGS IN ASBESTOS INDUSTRY 199 would now like to refer to the 12 cases pre- viously mentioned that were diagnosed as positive in 1928 and 1929 given compensation and discharged At one of the hearings they were called by the insurance nation we have the best and perhaps the only method of diagnosis of asbestosis at the present time The ray reveals the actual tissue changes in the lungs In a general way , Cast Cast es te. 8 Mr. more than six years intermittent Mr 4, more than six years exposure exposure Fig 4 company to ustrate that these 12 who had been found positive by both clinical and ray examination were by their own testimony free of all symptoms and ex- cept for several women in the group were doing laborious work in their new occupa- tious If tosis is a according according to Dr. Hawes asbes- progressive progressive progressive disease once con- tracted these individuals should have been in the samecondition as in 1924 and 1929 or much worse It would be logicallogical logical to assumethtat hat eight or nine years away from the industry without symptoms gives us very definite evidence that this disease provided we were correct originally is not a progressive one at least in this particu- history lar industry It evident that 7 a of exposure to asbestos dust is eliminated a positive clinical diagnosis of asbestosis cannot be made In other words there is no one physical finding or group of objective signs which are pathognomonic of asbestosis We are of the opinion opinion that in ray exami- these changes are much less extensive as compared with silicosis or anthracosis We find little parallel between the extent of the visible pathology and the severity of the clinical symptoms It has been impracticable to classify the disease into different stages All of our positive cases have shown about the same amount of lung involvement The theoretical early or incipient asbestosis a stage before visible lung changes are present cannot of course be diagnosed by the ray On the other hand we are of the opinion from our general observations and it is the opinion of several clinicians who have studied these cases that asbestos dust will not give symptoms until there has been sufficient tissue change to be visible on an ray film The average uncomplicated case of asbestosis gives rather consistent and characteristic ray findings In the first place there is an increased density in the lung fields This increased 200 RADIOLOGY Aug. 1939 density is characterized first by bilateral distribution and secondly by its being limited to the lower lobes of both lungs The quality of the shadow is characterized by a homogeneous quality and is described Fig 5 Py posure Case 5. Mr. H. more than six years in the literature as a ground or smuky appearance The microscopic changes in the lung show that we are deal- ing with an almost interstitial fibrosis with areas of atelectasis of the alveoli and Splier bronchioles Thereis an absence of the gross nodulation seen in silicosis What nodulation there is has a fine evenly dis- tributed quality There are no character- istle changes about the root shadows bothe cases are associated with hilum fibrosis and glandular enlargement but many cases of asbestosis show no variation In the appearance of the hilum shadows Often there is some accentuation of the branchial shadows There is frequently found a peculiar appearance of the bron- chial tree in beth lower lobes in that it presents a rather rather laminated appearance presents The peculiar arrangement of the bronchial bronchial shadows is apparently due to localized areas of emphyserna scattered throughout the lower lobus The microscope tells us at the basic pathologic change in the deposit of a protective element about the asbestos fiber rather than a destructive process of the lung tissue The asbestos fibers appear to be surrounded by a sub- stance uniform in character and having the appearance of connective tissues It would appear from a study of the slides that the fiber is innocent of producing any pathologic disturbance except an impedance to the air in this region of the lung In other words in are dealing primarily with asbestosis we an atelectasis due to the mechanical blocking of the alveoli and bronchioles by the protecting fibers about the asbestos fiber This peculiar diffuse microscopic fibrosis associated with atelectasis and microscopic areas of emphysema is the type of change that produces the called ground appearance on the ray film In the second place asbestos dust produces changes in the pleura the most constant finding being an accentuation of one or more interlobar pleural septa The microscope shows that fibrosis associated with the asbestos fibers is prone to involve the pleural covering of the lung The demonstration of pleuritic adhesions o both lower chests with obliteration of the phrenic angles is a rather constant finding in uncomplicated asbestosis In the third place the ray shows the usual signs of emphysema This ephysema of course is not pathognomonic of asbestosis but when accompanied by other ray indications can be considered of a confirmatory nature This evidence of emphysema is best demonstrated by the limited excursion of both diaphragms and the increased radiability of the lung tissue In the fourth place we have noted in the cases of asbestosis certain changes in the contour of the heart shadow which we feel is somewhat causally related to the process in the lungs Other writers have put considerable emphasis on the dilatation of the right auricle and ventricle as evidence of asbestosis It is our opinion that dilatation of the right side of the heart is seen in a higher percentage of asbestosis cases than in other forms of pneumoconio- Vol 38 GEORGE AND LEONARDI LUNGS IN ASBESTOS INDUSTRY 201 sis particularly silicosis There is a theoretical possibility that the type of inter- stitial fibrosis seen with the asbestos dust is such as to produce a mechanical interference with the circulation in the perialveolar capillaries and that this embarrass- ment in the pulmonary circulation results 1 some hypertrophyhypertrophy or dilatation of the sight side of the heart We have not ob- served any demonstrable dilatation of the pulmonary artery There are several points which are of importance in the diferential differential diagnosis between asbestosis and other forms of pneumoconiosis and also between asbesto- isand other shadows due either to faulty technic or to variation in thelungmark- ngs from other conditions not connected with the dust hazard It would seem un- necessary to mention faulty photographic technie It is our belief that many er- roneous ray diagnoses of asbestosis have been made on ray films which were either under exposed or exposed The physi- cal qualities of the individualshould also be taxen into consideration A woman with large breasts will give an ray picture which which may have all the characteristics of lung changecs hanges due to asbestosis The fact being however this variation in density is due to chest structurestructure rather than to changes within the chest cavity cavity . There are certain points of importance importance in the differential diagnosis of asbestosis and silicosis increased density in asbestosis is confined to the bases in silicosis it is primarily found both lungs and clear in the central portion of frequently the bases are 2 The nodulation of asbestosis is fine granular arees in silicosis nodulations are course and in the the the ad- vanced stages they become conglomerate producing areas of apparent consolidation producing ( The pleura is more likely to be in- volved in asbestosis than in silicosis The same is true of the hypertrophy of the right side of the hear in asbestosis In our experience this heart condition is rarely seen in silicosis In this particular industry which we have studied the percentage of silica where it was found in in the dust tests was less than 30 per cent and we have not been bothered by a combination of asbestosis and silicosis It is conceivable a> . 4a ony we? . oe e Bro ft & ve, cd ' aA : 2 ke Fig 6. Photomicrograph of section of lung showing asbestos bodies Courtesy of Liberty Mutual Insurance Company in certain industries and perhaps in the of mining asbestos we may have dust hazard of asbestosis with a high percentage of silica In the advanced cases of pneu- moconiosis dueto this double hazard it might be fairly easy to determine from the ray the amount of disease due to the silica and that due to the asbestos fiber but in the average case an accurate inter- pretation of pneumoconiosis due to both asbestos and silica would be a difficult procedure In this series of cases we have found no case of complicating tuberculosis From our experience we are of the opinion that asbestosis is not prone to the development of tuberculosis and we have had no case in which there was evidence of asbestosis lighting up a existing tuberculosis The differential diagnosis between asbes- tosis and tuberculosis is reasonably easy The diseases have little in common as far as their ray appearance is concerned This is not true in cases of silicosis com- plicated by tuberculosis It is sometimes difficult to make a differential diagnosis between asbestosis and certain conditions which produce congestion of the lower lobes of the lungs or accentuation of the , 22002 2 RADIOLOGY Aug. 1939 in the lower lobes must be taken into consideration The bronchial shadows with method of manufacturing whether it is Se k Chronic passive conwgeelsltisoinmualsastoecicaotnedditions - the dry or wet method is of importance et the dis- heart lesion might The differential diagnosis 2 We are of the opinion that of asbestosis asbestosis is not a progressive dis- in such an instance depends considerably ease the individual has been re- upon the clinical history Chronic bron- ease after moved from the dust hazard chitis or bronchiectasis might produce a with asbesto- 3 There is no evidence in our study of picture somewhat confusing asbestosis for the past ten years that sis but neither of these conditions usually causal relation to shows the characteristic ground in- asbestosis has any creased density over the lower lobes tuberculosis 4 It is our opinion that the final diag nosis of asbestosis must depend mainly on fy, It is our opinion that every in- dustry with an asbestosis hazard must be a special study in itself All asbestos min ing and manufacturing cannot be classified in one group as to the dust hazard The of silica in the asbestos dust percentage percentage the ray evidence that there are no clitical findings pathognomonic of asbes- tosis and that an amount of asbestos dust in the lungs sufficient to produce syniptoms will give visible evidence of tissue changes on the ray film ULCE By ^ K colle r withcolle tion all ; and t which s the roci ence to the litera unillust by H. E logical 1932 at on Ro Digestiv PatioIn the account made 1 nicher stomac denal 1 MP This : friends at