Document 0q6qVmR4b5wrN88MeKQoLoX6k

c C PLAINTIFF'S EXHIBIT the AMERICAN JOURNAL OF ROENTGENOLOGY RADIUM THERAPY AND NUCLEAR MEDICINE Voi.. So JULY, 1958 No. i SILICOSIS AND A FEW OF THE OTHER PNEUMO CONIOSES: OBSERVATIONS ON CERTAIN ASPECTS OF THE PROBLEM, WITH EMPHASIS ON THE ROLE OF THE RADIOLOGIST* CALDWELL LECTURE, 1957 By EUGENE P. PSNDERGRASS, M.D. PHILADELPHIA, PENNSYLVANIA Eugene Wilson Caldutll This is the occasion of the Caldwell Lecture and before I begin my address, I want to express to our president, Dr. Wendcil G. Scott and to the members w the Program Committee my sincere appreciation idr the honor fhat they have conferred on me in ask ing me to present this lecture before the American Roentgen Rav Society. I did not have the privilege cf -w--''fir Dr. Caldweil, but those who did have testified on many occasions of his ideals and achieve ments. This Society has been most fortunate in having many who have contributed much toward the advancement of medicine in general and of radi ology in particular. Our heritage is one of which we justly can be proud. I have the feeling that Dr. James T. Case and others who were responsible for the inauguration of the Caldwell Lecture, not only wished to honor Caldwell, but in addition hoped that this special event might become a symbol by which we could honor all of our members and those in collateral disciplines ofinvestigation and in in dustry who during their lifetime added their bit to our specialty. As evidence of this premise, the senior Dr. Wiliam A. Evans1* wrote the following: "The early second period of pioneering in American roentgenology was graced by several who by virtue of their nooie character and unusual professional attainments have been canonized by those who continued in the work for which these made the supreme sacrifice. One who wiil change the whole direction of his life current to follow an ideal conceived after comparative success in a given endeavor, must possess unusual attributes. Such was Eugene "7 of Vork^Already a master mind in the field of electrical engineering and physics, upon becoming interested in Rontgen's work, he early appreciated its importance both medi cal and otherwise. The better to serve its advance ment in the field of human reiief, Caldwell qualified himself as a physician. Thus trained in two highly technical and scientific spheres, he began a career which added greatly to the efficiency and complete ness of roentgen equipment and accessories and its proper adaptation for demonstrating various medical and surgical lesions." Dr. Evans goes on and describes the work of others and concludes with the following statement: "With Leonard, these three, Caldwell, Dodd, and Kassa- * From the Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania. Presented at the riiry-ejghth Annual Meeting of the Amencan Roentgen Ray Society, Washington, D. C., October 1-4,1957. tavjtonut/.nb'i 1 JU* c c v Eugene P. Pendergrass .July1, 19;? bian, succumbed to roentgen injuries incident to their constant studies. The American Roentgen Ray Society, conscious of their beneficent influence, hon ored Leonard by the establishment of the 'Leonard Prize,' an award granted at intervals for meritorious studies in some phase of roentgenology and com memorates the influence of Caidwei! by the 'Cald well Lecture'. ..." THE subject of my address is con radiology in which there is a greater oppor cerned with certain aspects of silicosis tunity for contributing real service to the and some of the other pneumoconiosesh.ealth of the community and of the na Many of you know of my interest in this tion. The retrospective studies of chest problem. This is the fourth time that I have roentgenograms made on industrial work used this subject in a named lectureship-- ers provide a most satisfying experience, the Preston M. Hickey Memorial Lecture44 not only in studying the natural history of before the Wayne County Medical Sociery, the pneumoconioses, but other pulmonary April 6, 1942; the Russell D. Carman Me and cardiac diseases. morial Lecture66-47 before the Minnesota Over the years I have talked with young State Medical Association, June 12, 1950; men who have trained with us in an effort and the Ross Golden Lecture49 in New to stimulate interest in the field of the York, March 21,. 1955, before the New pneumoconioses, and only a few have re York Roentgen Society. sponded. For the most part, radiologists My own experience on the effects of dust have been satisfied with a casual acquaint inhalation on the lungs dates back to 1919* ance with the subject. The information when following World War I, Dr. Henry that these men are qualified to render is K. Pancoast re-embarked on the studies oftentimes inadequate. Because of such which he. Dr. T. Grier Miller and Dr. indifference, internists, chest physicians, H. R. M. Landis began in 1916.42 Together, chest surgeons, pathologists and others are we carried out many studies over the suc now rendering interpretation of roentgeno ceeding years. Dr. Pancoast was the first grams in many places. We, as radiologists, radiologist in this country and one of the have a very definite obligation in improv few in the worid who early made a real ef ing this situation. fort to learn something about pneumoconi osis. In so doing, he developed many friends outside of radiology in the fields of public GENERAL ROENTGENOLOGIC CONSIDERATIONS health, pathology, chemistry, physics, en The proper roentgen interpretation of gineering, law, and industry. For me, meet- pneumoconiosis is dependent on; (i) a iroT iiAdjgetting to know others interested knowledge of the anatomy of the chest and in dust hazards Has been a most rewarding the physiologic problems associated with experience. its anatomic constituents; (2) a thorough Anyone who takes the rime to read a lit familiarity* with normal fiuoroscopic and tle about the pneumoconioses cannot help roentgenographic appearances and their but be impressed with certain facets of the permissible variations; (3) an understand total problem. Some of these are of real im ing of the histology of the lungs and espe portance to the radiologist. Most of the di cially the lymphatic system; and (4) a clear agnoses begin with an interpretation of the perception of the pathology of pneumo roentgenograms. A radiologist with a broad coniosis and of all conditions which may background of diagnostic training and ex simulate its roentgenographic appearances. perience can be a tremendous asset in the In many instances, the radiologist is ex care that these dust-affected workers re pected to render an opinion from a single ceive because there are many diseases that roentgenogram with or without an ade produce shadows in the lungs that simulate quate history. Under such circumstances, silicosis and asbestosis. There is no part of one has to do the best he can. A report  \ ,,\. is, No. Silicosis and Other Pneumoconioses 3 should include the conditions that should i)cr considered in arriving at the final or pre sumptive diagnosis. Although I have had the opportunity o/ ,ajdving roentgenograms of collective sur veys done by the Public Health Service, or some other like agency, my experience has been concerned largely with three groups: . I; The individual who arrives in a general hospital usually with a complaint relating tu some system or organ in the body other than the lung; (II) the individual who is wefting compensation for pneumoconiosis; and, (III) workers in an industry where there :< a hiown or unknown dust hazard, in cer tain ot' its operations. ! and II. The roentgen studies for the 'aural hospital patient and the individual echo is seeking compensation can be consid ered together, because the studies are es sentially the same. These include a fluoro scopic and roentgenographic study in addi tion to all of the aforementioned history review, physical and laboratory examina tions. It has been my practice to cake a supplementary history mvseif, making a real effort to learn everything about the in dividual's total environment. The fluoroscopic and roentgenographic studies should be planned to obtain good records of any lesions, and to demonstrate, a' possible, any roentgen evidence of disa bility. In pneumoconiosis, one of the prob lems of disability has to do with pulmonary ventilation. Vrnnlaripn acyclic process of inspira tion and expiration in which alternately fresh air enters the respiratory tract and an equal amount of pulmonary gas is exhaled/ An adequate ventilation should be ac complished without an undue expenditure ( energy. It is important to define several terms15 in order to avoid confusion: 5. Tidal volume (depth of breathing) is the volume of gas inspired or expired during each respiratory cycle. Residual volume is the volume of gas remaining in the lung at the end of a maximal expiration. 3. Total lung capacity is the amount ot gas contained in the lung at the end of a maxima] inspiration. 4. Vital capacity is the maximal amount of gas that can be expelled from the lungs by forceful effort following a maximal inspiration. There are many anatomic abnormalities which reduce the vital capacity and which can be demonstrated in roentgenograms of the chest/ These pertain to: anomalies in development of vertebrae or ribs,n scolio sis, deformities of the thoracic cage due to fractures, chickened pleura, and spaceraking lesions within the chest/ Lesions af fecting the position and mobility of the dia phragm may reduce seriously the vital capacity/ Changes in the interstitial tissue caused by edema, fibrosis, or granulomas are associated sometimes with reduction in total lung volume. Roentgenograms should be made in inspiration and in expiration without changing the position of the tube. Roentgenograms in each lateral view should also be obtained. . *The patient's chest should be studied fiuoroscopically in the erect, horizontal, prone and supine positions with horizontal and vertical beams, and in each decubitus position during quiet and forced respira tion, and after coughing and sniffing. Fluo roscopy during the Muller (sniffing against a closed glottis) and the Valsalva maneu vers (straining against a dosed glottis) is informative. This gives one the oppor tunity to determine the movement: -cf the thoracic cage; the position of the medias tinal structures in ail projections and during all phases of respiration; the pulsation of the heart and great vessels; the presence or absence of disturbed ventilation. It is well known that obstructive emphysema some times is seen best during fluoroscopy/9 While the fluoroscopic examination dur ing forced respiration cannot provide an absolute figure of the dynamic reserve of the lungs, one can get a good estimate of the movement of air by observing the movement of the diaphragm and thoracic cage.4 If fluoroscopy is combined with vital 'n i iixti f3 ,* >i -4 c 1 !,1 j 4 Eugene P. Pendergrass Ji i.r, capacity spirometry, the radiologist will improve his ciinical judgment.4 If the pa tient performs a maximal breathing ca pacity test, and there is limitation of' rib and diaphragmatic excursion, one will be able to obtain an explanation for the re duced function.4 The upper respiratory tract and pharynx should be included in the fluoroscopic study. The number of roentgenograms and the technique to be used should be decided af ter fluoroscopy. A minimum study should include roentgenograms in inspiration and expiration; in each oblique view (5 to 15 degrees); in each lateral view; and a posteroanterior roentgenogram with a PotrerBucky diaphragm. It may be decided to do laminagraphic studies and rotational laminagraphv, selective angiography, bron chography, or some other study. In approaching a comprehensive roent gen examination, one should keep in mind that the radiologist has an opportunity to make a real contribution. For example, al though lung volumes are easilv measured by the pulmonary physiologist, they vary so widely in healthy persons that figures obtained for pulmonary capacity do not necessarily reflect the presence of pulmo nary insufficiency.3 The most important aspect of pulmonary ventilation is the amount of air that reaches the alveoli and the uniformin' with which it is distributed to them.1 Any condition where air is pre vented from reaching the alveoli in suffi cient amounts results in hypoventilation with its consequences of anoxemia, CO- re tention, and respiratory acidosis.3 Condi tions such as asthma, asbestosis, silicosis, other pneumoconioses and emphysema are only a few that produce hypoventilation. Variations in alveolar ventilation/blood flow ratios may be diagnosed by exclusion in anoxemic patients. Hypoventilation can be eliminated by simple clinical tests flung capacity, roentgenograms for anatomic changes). Impaired diffusion of O- across the alveojar capillary membrane can be measured by more elaborate physiologic tests (CO? uptake).3 Structural changes in the alveolar walls may produce anoxemia in the presence of normal alveolar ventilation and aiveoiar blood flow by imposing a barrier to the pas sage of 0; across the alveolar-capillary membranes.3 This occurs in individuals with pulmonary fibrosis, pulmonary em physema, and other conditions such as some of the pneumoconioses; also mitral stenosis in an advanced stage. It can be de tected clinically, by determining that ar terial 0* saturation falls during exercise and is restored to normal values during the inhalation of O?.3 These are only a few examples illustrat ing an intriguing opportunity for radiolo gists to participate in a program of corre lating radiologic data with physiologic studies. Barden and Comroe,4 and Wright** have demonstrated the possibilities. It now behooves those of us who are located in in stitutions where there are good physiologic departments to do our part. In improving ourselves, it is not unlikely that real progress may be made in the detection of pulmonary dysfunction. III. Workers in an Industry-Dust Hazard Known or Unknown. With the industrial group, a different program is necessary. It is essential that the employers of workers in any industry or process known ro in volve exposure to injurious dusts encage the services of a good clinician. He must be familiar with the plant operation and must know the workers--their occupation in the plant and their heme environment. Such a physician is held in high esteem by the workers. This is important. Also the services of an industrial hygienist for peri odic conventional dust counts are most helpful. Whenever possible, the roentgenograms of employees should be made at the plant. This keeps the worker on the job, and one is more likely to obtain roentgenograms of good technical detail once a year. When the studies have to be made away from the plant, not infrequently serial studies will be interrupted for several years at a rime. Usually a good history is obtained, a Silicosis and Other Pneumoconioses ..i.-i/iul phvsicai examination is made and -:tv laboratory studies are limited to a test :..r piuiis, a biood ceil count, a urine ex..:;in;;ncn ana a sedimentation rate deter- uuiation. Tiic 'oentgen studies have varied over :i)c vears from stereoscopic and lateral exto singie posteroanterior roentgen- .^rnnis. At present I am planning to .wommend a new program for new em;j..vces with the view of crying to test cer tain techniques for demonstrating changes i iunu dynamics. It is hoped that the fol,..jng studies can be made on all new emj'inlfO: r. P>sceroancenor roentgenogram dur ing inspiration. Posteroanterior roent genogram during expiration. The tube level should remain the same. Posteroanterior roentgenogram with expiration and inspiration recorded on die same film as a double exposure. The tube level should not change for the two exposures. The expiratory phase of respiration should be ex posed first, otherwise one will not get good records of the two positions of rhe domes of the diaphragm and the ribs in inspiration and expiration. Right lateral roentgenogram of the chest in inspiration and expiration. The rube should be kept at the same level. 4. Tor the succeeding three years, a single posteroanterior roentgenogram the chest is to be recommended. t. The fifth year studies will be the same as the pre-employment examination. The full study will be repeated at fiveyear inrervals thereafter, with single posteroanterior roentgenograms dur>"g the intervening years, unless some abnormality develops. It is hoped that such studies will compensate for the lack of opportunity to make careful fluoroscopic examinations. As stated before, except for individual . a-** and a few collective studies on anthra cite and bituminous coal miners, pottery workers, iron miners, foundry workers and asbestos workers, my experience has been limited to a study of a singie industry in which the dust hazard is essentially pure quartz in a finely divided state. The work ers are middle class Americans and the great majority are white people. This study has extended over twenty-two years. In many of the individual cases, we have been able to obtain previous roentgen studies, making it possible therefore to learn something of the natural history of the dis ease. For some years, Tuddenham,*0 one of my associates, has been working on basic concepts of visual physiology as it concerns die radiologist. His work has been helpful in explaining some of our deficiencies. Some of these include: the avoidance of outside major glare sources striking the retina; working in a room with low lights instead of complete darkness or bright iiluminadon; and the use of diminishing lenses. The viewing room has 60 viewing boxes ex tending over one wail so that the roentgenograms of a complete case can be set up apone time. With double reading we think this plan reduces the number of errors in directing abnormalities and changes from year to year. Looking at several roentgeno grams, then removing those and replacing them with others of the same case, oftentimes leads to errors. With few exceptions, more than one radiologist studies the roentgenograms at the same time. This is most helpful in that it, on many occasions, prevents one fium u-criooking not only small but perfectly obvious variants or lesions. I have said repeatedly that if I were working by myself in a small community, my technician or helper of any category would be invited to participate in my studies at the time of reporting. Every radiologist has had or will have a member of his nonprofessionai staff call to his attention a shadow that was not evaluated in a report that has been prepared to be sent to thereferring physician. SIMPLE SILICOSIS The characteristic lesion insilicosis is a ' . : . 1 l : ; ; ; : ; ; 1 [ ; i S \ 1 j } ; [ I f \ I [ l r 6 Eugene P. Pendergrass >ly, ;*<| Fig. !. Eariy silicotic nodule showing the collection of epithelioid ceils which look like the tubercle for mation of tuberculosis. (Courtesy of Dr. Arthur J. Vorwald, Wayne State University, Detroit, Michigan.). , circumscribed nodule of hyaline fibrosis (Fig. i and -). The earliest lesions are in visible or are recognizable only micro scopically or with a magnifying glass.14 These parenchymatous nodules may con tinue to develop and ultimately reach a size of 3 to 4 mm. in diameter. Patholog ically, the nodules have well-defined bor ders except when there are accumulations of nonsiliceous dusts. The earliest roentgen findings that l ac cept as evidence of simple silicosis are the small, multiple shadows, i to 6 mm. in di ameter, more or less uniform in density, which do not disappear in a roentgeno gram made with slight rotation. Shadows that disappear with slight rotation are likely to be vascular (Fig. 3, 4 and 5). The blood vessel shadows are denser and their borders are more sharply defined than are those of nodular shadows. The shadows of the sili cotic nodules are usually distributed along and between the vascular channels and the bronchial tree of both lungs, and, on the roentgenogram, at times, they may be lim ited largely to one lobe. Not frequently, even though a bilateral distribution of the shadows occurs, does one see them in the apical, peripheral and lower portions of lung fields. . The roentgen appearance of the shadows Fig. z. (A) Silicotic nodules showing the hyalin* collagen fibers. Note that these noduies are often adjacent to each ocher. The nodules have varying shapes and are not cylinders of tissue; consequent ly, they do not appear as weil-denned circular shadows on the roentgenogram. They do not produce characteristic roentgen shadows that allow one to differentiate such shadows from the shadows of other conditions such as siderosis or miitary tuberculosis solely by the roentgen exami nation. (5) Larger field of the same case as A. Note the varying sizes of the nodules and their distribution not only in the lung parenchyma, but also along the visceral pleura. (Courtesy of Dr. Arthur J. Vorwald, Wayne State University, De troit, Michigan.) of the silicotic nodules is not characteristic and not as diagnostic as one would wish (Fig. 6, 7 and 8). Some are round, some oval, some irregular, some large and some small. Most of the lesions have a uniform density, but some have shadow densities in Voi. >, No. i Silicosis and Ocher Pneumoconioses 9 ! it., 'j. (d) Early silicotic nodulation in a pure quartz worker in 1936. (5) Conglomerate silicotic lesion in the s;ime individual twenty-one years iater. This worker is asymptomatic and has been so Tor several years, mi his lesion probably falls in the category of*simple silicosis. jcc.n on the roentgenogram. This observa hand, roentgenographic studies of patients tion apparently is true even when men are with such lesions frequently show them in working under similar conditions in the the upper half of the lung fields (Fig. 6). '.une industry, and, up to the present time, "Microscopic examination of the tissue from there is no adequate explanation. such areas often reveals no evidence of in When nodulation occurs, the nodules fection (Fig. 9). The nodules seem to be may or may not show progressive changes. closer together than in other portions of In a few cases that have been followed for the lung; they are less uniform in size, and T.hecn years or longer, I have seen the pat they are embedded in a matrix of diffuse, tern of nodulation replaced by massive fibrous tissue having the same characteris 'hadows, with either complete or almost tic appearance as that forming the nodules .nmplcte disappearance of visible nodular themselves.14 dubious on the roentgenogram. The shadow of the conglomerate lesion One may or may not be able to demon- in simple silicosis is often Jimcult tw dis .'Tare a definite enlargement of the hilar tinguish from that found in silicosis with i . in ph nodes. infection. From the roentgenologic stand Another lesion generally included under point it is impossible to differentiate in a r;ie classification of simple silicosis is the single examination, whereas serial examina - nail conglomerate lesion (i to 5 cm. in di- tions may or may not show slight changes in unietrr). Such lesions may result from a the extent of the shadows of lesions compli o-ivddnacion or coalescence of discrete nod- cated by an active infection. Roentgeno do, or the lesion, primarily, may occur as grams made with a Potter-Buckv dia phragm and/or laminagrams made in the Gmgjomerate lesions are usually local erect posture provide additional informa ize! and do not occur in the same portion tion which is helpful in evaluating the 'ii rhe long in every patient. On the other presence or absence of an infection. 1 10 Eugene P. Pendergrass Jl'tv, !$(! Fie. 7. Sarcoidosis of the lung in an individual twenty-six years of age. Note the pattern of the lesion in the right upper lobe. It could be mistaken for a pattern of a silicotic process. This case was proved by a scaiene biopsy. Including the conglomerate lesion under the category of simple silicosis is only justi fiable in those instances when repeated ex aminations over several years fail to show any roentgen evidence of change. The con glomerate lesion in simple silicosis is not a thick dense lesion, but irregular, thin, hav ing its longest diameter in the vertical posi tion. If, after all of the above qualifications have been considered, there is still doubt as to the true nature of the lesion, my plan is to regard the lesion as one of silicosis with infecrion either quiescent or chronic. The presence of well developed emphy sema may or may not be observed in sim ple silicosis. One cannot be certain whether the emphysema is due to silicosis or noc, es pecially if the pattern of nodulation is slight. When well advanced, it is relatively easy to diagnose with either the fluoroscop- V* C- i l Lry P i r t $ $ < rne K :ene * (an ** ith nvjmher ss- is ei v op- Voi. *c So. i Silicosis and Ocher Pneumoconioses 11 Fic. 8. (/f) Hemosiderosis m a man. thirty-seven. On August 9, >949. there was evidence or' a partern of noduiation in rhe upper lobes of both lungs, the right being shown here. (5) This exami nation was made two months later. Note the tremendous increase in the pattern of noduiation. Shortly after this, the individual was operated on and following a commissurotomy, died from a pulmonary embolus. Microscopic studies showed the presence of hemosiderosis. the increased size of the preaortic space; the increased volume of the lungs seen in the heavily exposed roentgenograms made in the erect and horizontal positions; the loss of fine lung detail in conventional ex posures; the widening of the interspaces; and the demonstration of bullae in super voltage roentgenograms are some of the criteria for diagnosis. In focal emphysema of slight to moder ate degree, careful fluoroscopy with well ac commodated eyes sometimes gives one the best lead. Increased pulsation of the pul monary artery may be present. Over exposed conventional and kyphotic roent genograms are helpful. In many Instances, we believe that emphysema can be demon strated by supervoltage roentgenograms ic nr roentgenographie examination. The barrel chest; the restricted movement and flattening of the domes of the diaphragm; Kin. 9. Modified silicosis in a conglomerate mass from a hematite miner. One does not see the well-de fined silicotic nodules, such as shown in Figure 1. (Courtesy of Dr. Arthur J. Yorwald, Wayne State University, Detroit, Michigan.) N i*# 3 } \ ie 4. J L:" % 4 jun r % H 1 r4 * a 3 J a 1 c :z Eugene P. Pendergrass jav, ,vf, better :han by ocher roencgen procedures. Enlargement of* the hiii is very difficult to demonstrate with certainty. Overexposed or supervoirage roentgenograms in the posteroanterior, oblique and lateral views are necessary. Laminagrams and rotational roentgenograms are helpful. Comparison with previous roentgenograms provides the most reliable information if the roentgeno grams are exposed well enough to differenti ate between vascular and lymph node shadows. SILICOSIS WITH INFECTION' In this group are included all cases of silicosis with detectable evidence of infec tion. It is not always possible in the living patient to determine whether the infection is active or inactive even in instances when conventional clinical and laboratory ex aminations are available. Under such cir cumstances, mistakes will occur, but if one exercises good judgment, the affected per son can be protected by taking the neces sary precautions. The lesions (either some or all^described as occurring in simple silicosis may be modified by infection. Other legions that may be found include: cavities (usually thick walled)--tuberculous in origin; le sions occurring as a result of anemic in farcts; massive lesions; mottiing; soft modu lation; distortions of the tracheobron chial structures; bronchiectasis; Reichmann's "rainstorm" streaking, distorted vascular pattern; mediastinal displace ment; extensive calcification in the hili, paratracheal region and in the lung fields; various degrees of emphysema and bleb formation; pleural thickening, interlobar and peripheral; pleural collections; pneu mothoraces; and deformations (flattening, peaking, individualization of costal com ponents and adhesions) of the domes of the diaphragm. The radiologist is rarely able to predict whether the infection is due to the tubercle bacillus or some other organism. One suspects, however, that in the ma jority of instances the superimposed infec tion is tuberculosis, for, as stated by Gard ner,25 the postmortem examinations showed an element of tuberculosis in 6o per cental the cases studied by him. Other infections and infestations include: staphylococcic and Friedlander's pneumonia; histoplas mosis; and fungus diseases. Some of the detailed changes occurring in the respiratory and cardiovascular structures as demonstrated by the roent gen examination in silicosis with infertion18-38-c,_<7-7u are summarized below. TRACHEA The tracheal shadow may be in a normal position, especially if a tuberculous process or some other infection is superimposed up on an already established silicotic process. In other instances the trachea is displaced backward and/or to one side. Frequently, there are calcified lymph nodes in the paratracheal region. They may be irregularly or completely calcified. Some have an egg shell type of calcification (Fig. 14). At one time, we thought calcification was largelv due to tuberculosis. Now we know that histoplasmosis, coccidioidomycosis and possibly other infestations and infections may produce calcification chat looks like tuberculosis. When calcification is incomplete, we sus pect that the process is not completely healed. HEART A HO AORTA On occasions, evidence of cor pulmonale is observed in the advanced silicotic pa tient. Many clinicians14 and^st-hers have- re garded this condition as a complication of silicosis. The relationship between cause and effect is difficult to establish in this in stance, and some cardiologists who have given considerable thought to the question find themselves unable to express an opin ion. Many of us who have been interested in silicosis for years have not been im pressed with the incidence of cardiac com plications. On the other hand, it is possible that with increased use of modern cardiac studies in the well-advanced silicotic pa tient, more evidence of heart changes will be found. But even if such evidence is ;9<$ ' should OCOC-. . ;ouia&- rarr.ng iscular roen t- ;n/ec u'. iarma] 'rocess ed uprocess. placed jenriy, .* paraariy or i \r one argelv . that and ctions ;sC e sus>ietelv lonaic ic pa ve roion of se and is in- have esrion opinrested n im- com>ssibie irdiac c pa is will ice is fe 5 ii ii. No. i Silicosis and Other Pneumoconioses Tumi, the cardiologist and the general pathologist know chat in the older age ar'uip of men not exposed to harmful dust, u iin are studied at autopsy, cardiac comniivations are not uncommon. DOMES OF THE DlAJ'HKAC* Jf considerable emphysema is present, rtie domes of the diaphragm may be de pressed and limited in their movements. \r times ic is necessary to have the patient v i nigh or sniff in order to demonstrate, -ucntgenoscopically, evidence of diaphrag matic excursion. Another abnormal appearance is multipic peaking of the domes of the diaphragm. It may be impossible to differentiate the leaking caused by pleura] adhesions from riur due to inelasticity of certain structures "f the lung. Both causes may be present. Many bizarre appearances of the domes re-ult from emphysema and contractions -vcondary to lesions within the lung and pleura. HIU & The shadows of the hili may or may not he within normal limits. They may be en larged or may be partly or totally obscured iiv larger shadows produced by lung le- -ams. Each hilus may or may not be dis placed upward, laterally or backward by .mitTacting scars of infected silicotic proc esses in the lungs. The roentgen appear ance of rhe hili may present a rather homo- w.nequs shadow as contrasted to the nor mal. There may be calcified lymph nodes ::: mie or both hili. The lymph nodes either r;;a\ be densely calcified, irregularly calci- r.cvi. or the calcium may be deposited in v .J) a way as to produce an egg-shell ap- rmrance. Calcification of lymph nodes is regarded as evidence of tuberculosis, histo- r-iaifiosis or some other process. If the hmph nodes are not completely calcified, tiwv are thought to be the seat of an infec- that is not completely healed. Such ....Lnce is not, as a rule, thought to hesig- --.aajv enough to justify recommending rhe individual be removed from his particular occupation unless there are other modifying influences. On the posreroanterior roentgenogram, one not infrequently sees a large shadow which may be unilateral or bilateral. For years these shadows were thought to be due to enlarged lymph nodes, and in some instances were created as lymphoblastoma. Now w realize that they may represent a lung lesion (massive) which has migrated to the midline and its shadow is superim posed on the hilus, thereby posing a diag nostic problem unless one has previous roentgenograms which demonstrate the natural course of the lesion.ss LUNGS The lung changes vary considerably. The lesions include: nodulation, soft nodulation, conglomerate and massive lesions, emphy sema, emphysematous blebs, bronchiecta sis, abscesses and cavities. The term "linear markings" is not em ployed by us. I presume that those who recommend the term use it to describe shadows in the peripheral portion of the lung and not for the shadows of the vascular markings. Such shadows are so ill defined that we prefer not to classify them. Modulation. The shadows of nodulation are similar to those described under simple silicosis and cannot be demonstrated by a roentgen examination in even* case of modified silicosis with infection. This is par ticularly true in certain industries such as hard coal mining and granite cutting. As al ready stated, the roentgen evidence of the pattern of nodulation disappears in some instances when massive lesions develop. Soft Modulation. The shadows of soft nodulation are much larger than those pro duced by nodulation and mottling, but are smaller than the conglomerate shadows. The description of such roentgenologic shadows is provided in order to emphasize a perinodular cellular reaction observed by rhe pathologist. Massive Shadows. These shadows varv from 5 to zo cm. in size. Some are round, some oval and some wedge-shaped. Some 3 Lifciti :V Vtl 3 -1 -.4 3 * 14 Eugene P. Pendergrass Jl'iV, !$;* involve an entire lobe or more than one lobe (Fig. 10). These lesions are usually due to extensive areas of hbrosis and are found anywhere. Frequently, they occur adja cent to interlobar fissures and involve ei ther the basal portion of the upper lobes or the apical portions of the lower lobes or the process may extend across the interlobar hssure and involve both lobes. In lateral views of the chest, lesions are often seen lying posteriorly. Rotational laminagrams are helpful in demonstrating the relations of such lesions. With overexposed roent genograms, laminagrapnic studies or roent genograms made with the Potter-Bucky diaphragm, it is possible to show some of the details of a massive lesion, such as dis torted and dilated bronchi, emphysematous changes, effect on the vascular structures, cavities and areas of calcification and casea tion. At one time most of the massive lesions were thought to be due to silicosis wirh in fection, but Riddell,u Gardner McClos- key44 and others question whether this is always true. Besides infection and vascular occlusion, Gardner* indicated that a "third essential factor may be minerals other than free silica." On conventional studies, air shadows in massive lesions simulate the appearance of cavities, but with laminagraphic examina tion in the erecr posture, dilated major bronchi sometimes are found to be the cause of the air shadows (Fig. ii.-/ and n,B-D). In conventional roentgenograms and laminagrams, at times, one sees shadows extending downward more or less perpen dicularly from the massive lesions toward the domes of the diaphragm. These are blood vessels and have been called Reichmann's "rainstorm" streaks (Fig. 12). These vessels are particularly striking when filled by an opaque material (pulmo nary angiography). The position of the ves sels is due to the contraction of the lung structures produced by the massive lesion. With selective angiography, one can now 3 3 3 :i Fig. ro. (//) Anthracosiiicosis in 2 fifty-seven year old man. The massive lesions involve die upper portion of the lower lobes and they seem to have extended across the interlobar fissures into the lower portion of the upper lobes. This individual had shortness of breath, emphysema and cough. The costal expansion and contraction was good and there was no delay on inspiration and expiration. The expiratory movement of the domes of the diaphragm was quite prolonged (over ten seconds). (S) The lateral roentgenogram shows the position of the massive lesions. These lesions lie posteriorly. dr n ;i- )r S )). ui V'S nrd .re :h- (/.1) Conglomerate mass in the right upper lobe (arrows) in a young man who worked in an industry union had a pure silica dust hazard. In 1945, the chest was normal. In 1947, several months before this 'duiy, he had acute pneumonia. The roentgen manifestations of siiicosis developed very rapidly there- after. pornon rtion of .ion and menc of n shows 11. t!i 1 Kiwntgenogram made in four years later. There are conglomerate masses in each upper * rf.'j March* iy$4. A small cavity is developing in the lower portion of the conglomerate mass (arrow). . April, 195j. The cavity is larger. No tubercle bacilli have been demonstrated. A presumptive diagnosis .mcniic infarct has been made, but frequent examinations for tubercle bacilli are continuing. 5 ill 16 Eugene P. Pendergrass Jl=tT, l*. Fig. ia. (A) The appearance of the biocxi vessels as seen in 19.76 in a person thirty-eight years old. The blood vessels in the left iower lobe are ill-uerined. Compare these with B. (3) Note the stringy shadows of the blood vessels seen in the left lower lobe. This occurs after the contraction of the left hilus upward by the fibrosing lesion in the left upper lobe and produces what has been described as Reichmann's "rainstorm" streaks. These shadows are cast by the blood vessels. Same case as A which is regarded as tuberculosiiicosU, involving each upper lobe. '1 demonstrate in the living patient, the fi lumen, but not complete obliteration, brosing effect of the massive lesion on the dyspnea is more dominant. This is a very surrounding blood vessels. Some vessels interesting observation. It may be a corol are completely obliterated; in'others, the lary to that of the partial encroachment lumen is variously encroached upon (Fig. upon the lumen of the renal artery (Gold- 3 ij). Vorwald81 tells me that in those pa blatt's kidney); where one may find i* tients with partial encroachment upon the hypertension with partial, but no elevation of blood pressure with complete oblitera tion. Selective angiography will show displace ment of vessels in .pfyfients who have em physematous blebs and bullae, and in lo 1 calized pneumothoraces and pieurai collec tions.*4 Si Calcification In massive lesions is re garded as evidence of tuberculosis or histo plasmosis (Fig. 14). Sputum examinations and skin tests may be helpful in making the diagnosis. We have observed a migration of massive Fig. 13. Endarteritis obliterans occurring in a sili cotic person with a conglomerate mass which was an anemic infarct with liquefaction necrosis. (Courtesy of Ur. Arthur J. Vurwald, Wayne Uni versity, Detroit, Michigan.) lesions toward the hilus in certain instances (Fig. 15).** Just why this observation was not recorded years ago may be explained on the paucity of serial examinations and a failure to put all of the roentgenograms on  , N'o. i Silicosis and Other Pneumoconioses ttfi I $* t I . . u. Tibercuiosilieosis or hisroplasmosiiicosis in a sixty-seven year old individual who has been followed \.r uk-er twenty years. The calcification in the massive lesion has gradually Increased over the years. This i-nruenogram shows some of the types of calcification that may occur in histoplasmosis or tuberculusis. :iu' view boxes at one time. In other words, presence or absence of modifying factors." fwiie looks at die roentgenograms of serial The observation of migration has been 'Miiics one at a time, the slow migration hetpfuj, and explains the pathologic physi- .1 dl be missed. In some of the workers ologv simulating the shadows of greatly en- L w;th lesions near the midline, in our first latged hilar lymph nodes. st-lS,iy, it was possible to get earlier roent- Kirby44 has operated on and removed 9 _cn.>grams which when compared with massive lesions, the operations being per- ..t.r* provided a clue as to what was hap- formed because of a diagnosis of suspected : rning. carcinoma of the lung. The lesions were After noticing the migration of the mas- unilateral single masses usually found in ,\c lesions, I studied the work of l.ubert hard coal miners, without a pattern of aiui Krause on lobar collapse and broncho- nodularion (Fig. 16 and 17). A similar ap- j-.diMOttary segments,*8,4* and learned that pearance was seen in quartz workers. All of :iie\ were observing migration in lung le- the lesions proved to be silicotic, without ^;uns. These authors4* state: "The lobes do evidence of carcinoma. :u.r merely shrink to become smaller repii- The roentgen diagnosis in the first of , ;is of themselves. As they become smaller Kirby's patients was "probable carci- nup change from a three-dimensional, noma." On that basis, the patient had a p.ramidai or conical figure to approach a lobectomy. I was upset over the roentgen r.^dimensional triangle and flatten along diagnosis because the lesion had the ap- :iw mediastinal and parietal pleura. With pearance of a silicotic massive lesion. When v-mimiation of the collapsing force, they the second patient came along, I was asked along the curved surface of the chest to give an opinion. On the basis of a single ...ill toward the hilus, the direction of the lesion and marked encroachment on the movement depending on the natural con- lower lobe bronchus, a diagnosis of carci- ri-mration and position of the lobe and the noma was made. At operation, the lesion bitt i3 Eueene P. Penderzrass i '`.r, i$:> Fjo. 15. (^) Silicosis with infection in an individual twenty-seven years of age. This examination was made in I9J7. Note the lesions in both upper lobes as indicated by arrows. (B) Silicosis with infection in a chirtv vear old individual who was exposed to essentially pure quarts Note the lesion in the left upper lobe which is close to the periphery. The lesion in the right upper lobe has migrated toward the mediastinum. This examination was made in 1942. (C) Roentgenogram taken in 1957. The lesions in the upper lobes are continuing to migrate toward the hiius. The one on the right side is scarcely seen at this time. The one on the left side has migrated considerably since the previous examination. proved to be a silicotic mass. Approximate ly one year later, the. follow-up roentgen study of the chest showed a large mass in the upper lobe. It was thought that a carci noma was missed at the first operation so me patient was re-operated upon. A siiiconc mass was found at the second operarion. A recent.examination, seven years after oper ation, showed no massive lesions. The development of lung masses follow ing operation is thought to be an aftermath of lung trauma. Because of that observa tion, I have been somewhat concerned about lung biopsy. The experience of Theodos et aL'* and Effier and his collabo rators17 in over 100 individuals who had lung biopsies done under local or general anesthesia shows that the procedure is safe and quick and that an accurate diagnosis can be obtained. If Vorwald is correct in his impression that massive lesions with partially occluded vessels may be a dominant factor in caus ing dyspnea, one should consider removal of such lesions if by selective angiography one can demonstrate evidence of partial oc clusion of the vessels. We are now fully aware that nodularion is not necessary in order to make a diagno sis of silicosis in an unilateral massive le sion in a coal miner. The thoracic surgeons are not as convinced of that fact as we are at this time. Krause and Luberr18 made an observation which should be considered when making a diagnosis of carcinoma. They feel that the presence of a shadow of unknown etiology in an anterior segment should impart a feeling of special urgency because in these instances the possibility of neoplastic disease is somewhat greater. Al though many of the massive silicotic lesions are posterior, we have found them in the anterior segment of the upper and lower lobes. Emphysema. Emphysema may be focal or generalized. Gough,31 Fletcher,1* Gil son and Hugh-Jones,57 and other English investigators,io.n.a.a.4o.si.ia.;j jn excellent studies, have re-emphasized the difficulties in determining the presence or absence of emphysema or its extent, when present in coal miners. We will consider emphysema under another heading. In pure quartz workers emphysema is present, but is not the major factor chat one `9 j* one 1. A ner ow. :arh rvaned of 1 bohad era! safe oris sion ded aus>val phy . oc- cion :no! lerons are :Trreo- ma. H Of ienr :ncy v of ' Al iens the jwer ocai Gil:lish lent Ides e of ;t in ema a is one N'O. i Silicosis and Other Pneumoconioses 19 1 /. Anthracosilicosis in a fifty-seven year old coal miner simulating a carcinoma of the lung. This individ ..J iuii a tyeJve year history of cough and dyspnea. There was a aa pound weight loss in two years. nTi.<\cnoscupy had-revealed an extensive obstruction of the right ir.aa. broRwhu-* V.J. stsir.ud secre- t:,,ns. The Papanicolaou smear was regarded as negative. A roentgen examination in November of 194$ ,'usiwed a mass at the right hilus. There was no roentgen evidence of nodulation. Laminagrams of the right km:* urea showed evidence of encroachment on the lumen of the right main bronchus. The patient was i.^raml on and the mass was found to be anthracosilicosis. '=.r> in the coal miner. Gough'91 expressed r.'.nrc concern as to the effect of emphyse ma utt the heart chan one usually hears in this country. Dyson,18 in his comjrrflfs about the heart, was talking largely .11hi? his experience with coal miners. When focal emphysema is present, its :;.u:m>sis is not easy, as mentioned previ ously. The supervoltage roentgenogram is sometimes helpful in showing focal emphy sema along the peripheral portions of the lung. Bleb and Bullae Formations. These can readily be seen in most instances. If very large, they will displace and distort the vascular and bronchial trunks. 3 4m JO Eugene P. Pendergrass Jl'UV, I 9;* Fig. 17. (^) Same ease as hlgure ifi, /our yean later (November io, 1952). There is a mass in the right upper lung field which from the roentgen standpoint was interpreted as anchracosilicosis. The surgeons thought it was a carcinoma. (5) Lateral roentgenogram, showing the position of the mass. The lesion was removed and found to bean xnthracosilicotic mass. (C) This roentgenogram was made in July, J957. There has been no return of the anthracosilicotic mass. The shadow in the right upper lung field is due to the appearance of the ribs following thoracotomy. There is no roentgen evidence of anthracosiiicosis at this time. (D) Lat eral roentgenogram made in July, 1957. No. t Silicosis and Other Pneumoconioses ii livnuchicctasis. This, when present, may he Jemonstrared by erect and horizon cal uuninagraphy or by the injection of a waretooiubie opaque medium. The bronchiecrasis may or may not be due to the siliM>ric process. 1/ there is no causal relation ship, the bronchiectasis is o/ten observed in rhe left lower lobe, but it may be present .in v where. Abscesses. Following pneumonia or merastasis irom infected lesions elsewhere, ab scesses, when complicating a silicotic pro cess, act very much like abscesses in nonsiiicunc lungs, except that they may be re sistant to antibiotic therapy. If the inside uf the abscess wall undergoes epitheiizauoii, it becomes chronic with intermittent inflammatory reactivation. When this oc, >irred, lobectomy or some other surgical procedure had been performed in our cases. Cecities. These are most often due to a Tuberculous process, but are also seen in , arcinoma. The walls may be thin or thick. W here the silicotic process is quiescent, riic cavity may be thin walled as is seen in Tuberculosis without a complicating silixONis. When the silicotic process is active, rhe wall is .often thick, irregular and shag . 1 have not had enough experience with the use of antibiotic therapy in these cases r<< have an opinion as to their response to rre.ianent. 1M.C*A Occasionally, one sees a pneumothorax (.implicating silicosis. In such instances the i-\(enr of any pleural thickening may be .fi.ujeu. 'mpyema and ocher pleural leM<>ns may occur. Since the onset of antibaitics and sulfonamide therapy of lung in'Vvf.ons, one rarely sees empyema in the 'Tcuric patient. ITUVRCULQSIUCOSIS AND SILICOSIS WITH TUBERCULOSIS The roentgen manifestations of tubercui->iJicusis are protean, and yet distinctive.70 Only rarely is one fortunate to see the uolv.tmn of the entire process in a given panenr. It would seem, however, that the p.iumlogjc evidence is sufficient and that adequate numbers ot cases have now been followed by means or serial roentgenograms over a period of years to- warrant a pre sumptive diagnosis of tuberculosilicosiV either upon the visualization of modulation with concentration, coalescence or con glomeration, or, when the involvement is bilateral, upon the demonstration by them selves of large areas of conglomerate or massive hbrosis. Commonly, these areas of conglomerate fibrosis continue over the years to increase slowly in size, incorporat ing within themselves more and more sili cotic noduies from adjacent portions of the lungs, until finally one may have as the end-result either single or multiple, uni lateral or bilateral massive shadows of fibrosis (Fig. Til). As healing takes place, calcification often is observed in heavily ex posed roentgenograms. The trachea, hill, and other mediastinal and lung structures may be displaced by scar contraction, es pecially if the lung lesion extends to and involves the pleura. One may see evidence of varying degrees of emphysema. The Ranges may be so extensive as to obscure tFie details that are associated with either tuberculosis or silicosis. As these individ uals are not toxic, it is thought that the emphysema accounts for the disability, but disturbed blood supply may also be a factor. As indicated previously, some of these lesions undergo cavity formation. It should be borne in mind that histoplasmosis may simulate a tuberculous process so far as cal cification is concerned. We have observed extensive changes take place over a period of three to five years in some patients who were diagnosed as having tuberculosilicosis, but in whom no recognizable tubercu losis was found at the postmortem exami nation. Limited reservation must, of neces sity, be entertained, however, until the case for or against nontuberculous infec tion as the etiologic agent is definitely proved. Silicosis with tuberculosis may occur in either of two forms, the clinical course and roentgen behavior of which are as disdne- jii Eueene P. Pendergrass Ju.r, :9;< Fjc. i 8. Silicosis with infection, possibly tuberculosilicosis. (^) Appearance of right upper lobe in a siiica worker, thirty-eight years of age in 1936. His chest was thought to be heaithy. (5) This examination was made in 1945. A conglomerate shadow has appeared since eariy modulation developed in 1937- (C) Roent genogram made in 1951. Note the progressive increase in the size of the lesions. (D) Roentgenogram twenty years after the individual first developed this lesion. Note the caicmcarron in the hiius. We have never found any clinical or laboratory evidence of tuberculosis. He has not been skin tested with histopiasmtn. This series illustrates the development of a massive lesion in a single individual who has had exposure to quartz dust with very little if any other dusts in the atmosphere. rively different as is their pathology. In thefirst group are those in which there is a fresh infection, either new or arising from the reactivation of a latent focus, su perimposed upon a progressive and still ac tive silicosis. The general tendency is toward uncontrollable extension to death before there is opportunity for the chronic 7* r4 ' n ir i ar A* V' ,; ? 3? :.n i ica vas muy ver tin. to IC- is th tic So. I Silicosis and Other Pneumoconioses -3 ..i.'wr* of ruoercuiosujcosis to occur. used in their study can produce progressive K.i , j \' 4 several years may elapse before and -ratal pulmonary tuberculosis in guinea .v. xvntptoms supervene. pigs whose tissue resistance has been modi l>. t!u acond group art the unusual but fied by the inhalation of quartz dust. 1 v-u-nt cases in which silicosis and ruber- know of no study of this type among silica occur together but act independent workers. .. The infection, observed by means of .:.ii roentgenograms, is seen to behave RAPIDLY DEVELOPING SILICOSIS as it does in nonsilicocic sub- This type of silicosis3 is not seen very The tuberculosis develops upon a often. When it occurs, there are two causa . 4, ground of an already stabilized silico- tive factors that seem responsible--gross . . ;n \\ hich the quartz particles are pre- overexposure to finely divided silica and a . ..r,J>iv completely isolated within their complicating infection, especially tubercu .,,> nodules and thus exert no effect on losis. On two occasions, I have had the op '..perimposed infection. We have then portunity to study* serial roentgenograms .-pii the coexistence of silicosis and tu- in rapidly developing silicosis; one group Josis within the same patient, but was exposed in drilling a tunnel and the nit modification or acceleration of ei- other while bagging silica sand. I have not . - disease process by the other. seen a single case of this type within the Ki v cntly, we have observed another past ten years. I-.-. The patient was a relatively young The early roentgen appearance is that of *irh widespread disease, which devel- a diffuse haze in the lower lobes, especially verv rapidly. The distribution of the on the right side. The roentgenogram is . was similar to that seen in miliary not too informative, but the fluoroscopic ulosis. The patient had tuberculosis study reveals some limitation of costal and -:.v larynx. Hoarseness was the chief diaphragmatic expansion. -paint. The patient did not have any * In the more advanced lesions, there is . ;mr any signs of toxicity, but he had evidence of iobar and/or lobular consoli biopsy and his sputum was posi- dation. In the chronic cases, the lower lobes . ;>.r rubercie bacilli, show chronic scar contraction and the lung i ick and Pope4 in discussing cu- ventilation occurs largely* in the upper of "yesterday and today" call lobes. . .tjun co the falling morbidity and morrates. The incidence of tuberculous PULMONARY PHYSIOLOGY STUDIES and tuberculous disease is grad IN SILICOSIS ...... decreasing. Cooper14 states that this Wright,** in summarizing his observa .?v.rrinn carries over into the silicosis tions on pulmonary physiology* in silicosis, . Factors such as better nutrition, states that the earliest form of silicosis, gen *.* housing, less crowding, and isolation erally classified as simple discrete nodular pvn cases of tuberculosis are responsi- silicosis, is attended either by no recogniza <. >>per14 does not know of any* good ble physiologic alterations of function of . to show that there is decreased the cardiorespiratory* apparatus, or, at . .leure of the tubercle bacillus. He states most, by very slight ones. It is not surpris . --me phthisiologists have emphasized ing to me that such a statement is made, rite race as a whole shows improve- even though it may be modified when in resistance. Vorwald et a/.,** in more information is available. The lungs . - 'Uidies of the effect of BCG* vaccina- have tremendous powers for compensation guinea pigs with silicosis, demon- in health and disease. vondusivelv that the BCG strain When conglomerate silicosis develops, C.incKcUjucha. one usually finds alteration of pulmonary feitl 3*ti r C i Eueene P. Pendersrass Jutr, function.'0 The maximal breathing capacity is usually reduced, the residual v'ulume is increased, and the oxygen ventilation equivalent may be above normal.*4 The findings are like those /bund in diffuse ob structive emphysema. This type of abnor mality can be demonstrated by fluoroscopy and roentgenography, but Wright44 con siders that for practical purposes it should be said that in all stages of silicosis, the se verity of impairment of respiratory func tion bears only the grossest correlation with the ex tent, of the disease found in the roentgenogram. This is not discouraging-- there is an opportunity for the physiolo gist and the radiologist to pursue further investigative work. ASBESTOSIS * The roentgen findings in asbestosis are seen first in the lower half of the thorax. This form of pneumoconiosis is notoriously difficult to diagnose during its so-called early stages. In fact, the patient may have symptoms of what in this country is often diagnosed a slowly-resolving vgus pneu monia evidenced by weakness, chronic cough, but no fever. The roentgen findings in such patients after the disappearance of the pneumonia are essentially within nor mal limits so far as the fluoroscopic and roentgenographic observations are con cerned. Vet, in such individuals, the micro scopic studies of lung biopsies show thick ening of the walls of the alveolar sacs and the respiratory bronchioles, aftd excellent examples of well-formed asbestos bodies /Fig. 19). My experience, therefore, is not in accord with that of Cartier who says that "no cases of asbesrosis of clinical im portance have been diagnosed by the path ologist without having been derecred an teriorly by the roentgenologist." I must hasten to say that 1 have not had lung bi opsies on mine workers, but have had a few microscopic studies of lung biopsies on mill and textile laborers and on an individual whose work was concerned with covering pipes with asbestos for insulation purposes. In'answer toa'query** as to'cne'presence of asbesrosis in a 195; roentgenogram of a fifty year old man who had worked from 194Q-1945 covering pipes with asbestos in. suiation, it was suggested that the exposure would have had to be much more severe in order to produce asbestosis. After seeing and examining a well-advanced and proved case of asbestosis in a man whose occupa tion was covering pipes with asbestos ma. teriai, I find it difficult to express an opin. ion on just how much and what kind of ex posure is necessary to produce asbestosis. For years, workers in covering pipes have not been thought of as working in an un usually dangerous dust hazard. The pa tient, referred to above, was a self-em ployed individual, intelligent, and although he knew asbestos dust could produce lung damage, he felt that he was not being ex posed to enough asbestos dust to hurt him. self. The..dust.hazard in.this instance wag produced by sawing and Acting the cover-, jnes. (Fig. ao)T ' A careful fluoroscopic and roentgeno graphic study should be made of all work ers going into the asbestos industry. A number of these workers are women, so one has to be concerned with the confusing shadows of the breast in women and heavy pectoral folds in men. Stereoscopic roent genograms are helpful. Roentgenograms exposed in full inspiration and in full expi ration in the posteroanterior and right lat eral views, and posteroanterior views in each decubitus position will greatly assist as a baseline for future comparison in order to detect the earliest roentgen evidence of deviation from the normal. Oblique views (15 to 25 degrees) are most heipful in dem onstrating pleural changes. For the most part, the roentgen signs are not recognizable until the fibrosis has ex tended to and involved the visceral pleura. Early visceral pleural changes are not seen except at the interlobar fissures and then only when one makes special exposures in the cephalic or caudal views centered along the interlobar fissures (Fig. 21). I have found the expiratory posteroan terior roentgenogram heipful in studying cS -c re .n 'S td aa n xs. -e n- a n- ih ig xn as o k- $ A |i ne $ A'C , V 7" \t- " ns | 1C- k .ch ? >a to ot :ws :m- are exlra, een hen 5 in ong WM* Silicosis and Other Pneumoconioses d 2? .. i.yj Several asbestos bodies in the lung. Note the various shapes (arrows) and the irregular ueposit ...i.i the asbestos fiber. Some asbestos bodies have terminal giobular swellings and transverse markings. There are two large collections of.^-sbeatos bodies. (Courtesy of Dr. Arthur J. Vorwaid, Wayne State <.fjity, Detroit, Michigan.) in tact, sometimes it seems to , ;.ie more reassuring evidence of dis- rhun is obtained on the inspiratory : jvnogram. :u- earliest roentgen evidence of asbes. a presumptive limitation of dia..marie and costal expansion and roent-Taphic evidence of restricted move -( rhe vascular shadows (elongation pararion of the truncal shadows). Such findings must be presumptive unless pre-employment studies are available for comparison. Retrospective studies are in valuable in asbestosis. Oftentimes the roent gen evidence of asbestosis is seen best in the left lower lobe. Just why this occurs is not known. Gradual disappearance of the lateral costophrenic sulci is a helpful diagnostic sign in asbestosis and is interpreted as evidence m z6 r Eugene P. Pendergrass Mr. 19$1 Fig. 20. (4) Advanced ashestosis in a man fifty years of age. This individual was selfemployed and the exposure was caused by c covering pipes with asbestos. (3) Lateral roentgenogram showing the tremendous thickening of the pleura. (C) N'ote the thick ening of the pleura in the heaviiy exposed roentgenogram. -- 5r* Fig. it. (4) This worker is forty-one years of age The roentgen finding* are essentially negative. He has worked for ten years as a weaver. (B) Well advanced asbestosis in the same individual at forty-six years ofage. He has now been a weaverier fifteen years. Note the marked changes in the right lower lobe and the difference in the roentgeno. graphic appearance as compared to thar observed five years previously. The changes in this indi vidual are more prominent on the right side. The right dome of the diaphragm is eievated. of pulmonary and pleural involvement. The sharp outline of the cardiac silhouette gradually becomes ill-dehned due either to the blurring shadows of superimposed structures or thickening of the visceral pleura (Fig. zz). My explanation for the exaggerated pleural thickening in the lower lung areas is chat the pleura seems to show greatest thickening in those areas where there is greatest mobility of the structures. :95s- V % . * i c -1 age. He Well ii at sf for right ieno:rved indi- The s the jwer how here jres. \vi.. JC. So. 1 Silicosis and Other Pneumoconioses -7 Possible trauma exerted by the fibers on rhc surrounding structures during respira tory movements is the real factor, not only in causing pleural thickening, but also in producing prominence of the left lower lobe markings; the cardiac pulsation may act as an additional factor. In the advanced stages, the diaphrag matic excursion is markedly-disturbed; the lower lung fields have an appearance of hy poventilation plus a leather-like or ground glass density. All structures, including the borders of the cardiac silhouette, are illdenned (Fig. 23). The pleural shadows are greatly thickened, the thickening being less in the upper portions of the chest. The upper lung heids are ventilated, possibly hyperventilated, at times giving one the impression of emphysema. Asbestosis may produce shadows of a nodular pattern or ir regular, stringy shadows not only in the lower lobes but in the middle or upper lung fields. The vertical diameter of the chest (first rib posteriorly to level of domes of diaphragm in inspiration) is reduced. Fre quently, the elevation of the left dome is more pronounced. Pulmonary Physiology in Asbestosis. Wright,** in his studies of asbestosis, showed that there is little and oftentimes no im pairment of ability to ventilate the lungs in the typical asbestotic person, as meas ured by maximum breathing capacity. There is a slight to moderate reduction in total lung volume.85 It should be possible to show this by fiuoroscopy and with roent genograms by demonstrating the restric tion of thoracic and diaphragmatic move ment. When lung fibrosis is extreme in ex tent, the maximum breathing capacity is limited, but fiuoroscopy shows little or no impairment to emptying of the Iung.;T-" Gas studies of 0* and CG* show un impedi ment to the passage of oxygen across the al veolar membrane,, and during exercise the person with asbestosis overbreathes.*5 In spite of these and other complementary ob servations, Wright45 indicates that it should be emphasized that his data show that an individual retains his average capacity for work in the presence of incomplete oxy genation of the blood. Wright,*5 in his dis cussion on asbestosis in connection with correlation of the roentgenologic and physi ologic pulmonary studies, states--"that fciti Jfctf r !* l c / :S Eugene P. Pendergrass Jciv, three situations can exist: ;'i) physiologic abnormality without any definite roent genologic abnormality, (2) roentgenoiogic abnormality plus physiologic abnormality, and (3) roentgenologic abnormality with, out any physiologic abnormality." Tuberculosis and Asbestosis. My experi ence has led me to believe that asbestosis does not predispose or render a person more susceptible to tuberculosis. When tubercu losis does occur in an individual with as bestosis, its roentgen manifestations are es sentially those of one who has had no com plicating disease (Fig. 24). I am aware that there is difference of opinion about suscep tibility in asbestosis and suspect chat other factors may be of major importance. Fig. aa. (^/) Asbestosis in a fifty-four year old man who worked as a laborer for four yean operating a shaker which removed dust from the ashesto* fiber. There was a mechanical ventilator in a large room with three windows and a door. This indi vidual was in normal health until August, 1945 when he developed a dry hacking cough and dyspnea on exertion. There was a dull subscemai pain. One can see evidence of fairly advanced changes in both lower lobes. There is definite thickening of the pleura on both sides with some obliteration of the coarnphrenic sulci. (8) 'Hie closc-up study shows the marked changes in the COAL WORKERS' PNEUMOCONIOSIS The pathologic studies of Hart ct al Gough,10 Heppleston,1* Gilson,5* and the roentgenologic and epidemiologic studies of Fletcher and his scientific associates21-2 have been responsible for a new concept in pneumoconiosis. If Collis12 could examine the pathologic and epidemiologic data that have been collected by Gough and his col leagues, I feel sure that he would modify the statement contained in his scholar!) Milroy Lecrure which reads as follows: "some dusts, such as coal, it is true, not only appear to have no power of produc ing pneumoconiosis, but even may pos sess some inhibitor.* influences on phthi sis; ..." Re-orientation concerning the pneumo coniosis problem among the anthracite and bituminous coal workers has been difficult for many of us, who, for years, have been disciples of those who believed preponder antly that disability was the result of the fihrogenetic effects of finely divided silica. Rammer*2 feels chat we in America should re-assess the whole problem of the miner. I right lower lobe. Movement of the domes of the diaphragm was fairly good in spice of the exten sive lung changes. It was difficult to demonstrate good cardiac pulsations because of the overlying shadows in the lung field- The roentgen kymographic studies showed fairly good amplification of the pulsation of the heart. i i')) 8 iuglC >ent- Jo Jiry. >irh- peritosis more rrcui as*e cs- com- riiat ?tiier L " rhe jdies es51~ pt in m i ne that > col- JilalirClN lows: , not >duc- posiuhi- umo- ; uJid ncult been nderr rhe iiiica. lould ier. I of rhe extenistrute riving kymrv cation L. , Nu. : Silicosis and Other Pneumoconioses be inclined to extend the re-assess?r workers in other industries--two s.d-.'.plo being the talc workers in the tii' New York, and the goid miners in Australia.1 I iic work of'Gough and his colleagues is r important in another respect. There mam well-trained young men in indus , public health, and medicine, who have . techniques which extend beyond the rfN oi` rlie microscope; beyond the previ. toniepcs of acceptable dust counts for .(..tirin' armosphere; and, beyond old ,i> on environment. Lastly, but not they cannot be as completely dedito silica as I found operative in my blinking. The future for better work. .md living conditions should be bright. 1 diuuitl be emphasized that many of .,al miners in this country have had -ures to silica from hard rock mining the parhologic process in their lungs . nut correspond to that under discus. i'hcir disease is one of a modified sili. /.<., anthracosilicosis. That form of .m*coniosis is not being considered -9 > -.! workers' pneumoconiosis is not a . unbirion. I " occurs largely among .. who work at the coal-face, but it oc here also, even among those load . :ivv uwi into the ships.2 i-; tnc pathologic studies of Hart et a/.,3 .. ..'h." and Heppleston,3* it was noted .: riic condition is pathologically distinct -ilicnsis. The lungs contain large., ::ries of coal dust, which is aggre. :. ; ;ntn foci about the respiratory bronLa. The fibrosis is sparse, the coal dust .* Ik-IJ in a fine mesh of reticuiin fibrils, m appearance. The second finding but rhe pathologic process was the .... m every coal field, suggesting that - ^ nothing biologically peculiar about The third finding was chat the has two forms. First, simple pneu- . which is characterized by small -,f coal distributed throughout the .ilioc foci being surrounded by small emphysema, so-called focal em . Seamdly, infective pncumoconi- Imc. 23. (./) Well advanced asbestosis in an indi vidual fifty-three years of age who had worked for over thirty years with asbestos. He had dub bing of the fingers, chronic cough, dyspnea, anor exia and fatigue. Note the partem of the disease throughout both lungs, especially in the left lower lobe. (3) The close-up study illustrates very well the changes in the lung and shows the thickening of the pleura along the right lateral chest wall Eugene P. Pendergrass Jutv, 19c* r c Fic. 2+ (A) Asbestosis and ruberculosis in a fifty-nine year old individual. Note the peculiar ground-glass appearance in the left lower lobe. This was also present in the right lower lobe, but not to the same extent as in the left lower lobe. (B) Close-up of the ieft lobe which shows the roentgen abnormalities to better advantage. (C) There is evidence of an oid tuberculous process in both upper lobes, but seen best on the right side. osis, which starts as a collagen fibrosis within a few coal foci and subsequently enlarges and coalesces to form a dense mass of fibrous tissue occupying much of a lobe or even a whole lung. This second form is thought to be due to tuberculosis super- imposed upon a lung heavily laden with coal dust. The roentgenologic manifestations art classified as follows:** Simple pneumocom. osis refers to those cases having minut shadows throughout both lungs. Stmpk s in a ' Cnc iiw. : right t as in he left lulities uience upper uen with.. tions are lumoconig minute , Simple; S'a. I Silicosis and Other Pneumoconioses ; -.ru.'noconiosis is subdivided into three .^ories of increasing profusion of the : -v:tTe shadows. Complicated pneumoconi- . refers to those cases having shadows of ,.,,-rr si^e. Complicated pneumoconiosis is ; .;cii into four categories: (A) Shadows ...giving at least one anterior rib space, .-craily more or less circular, i cm. in di,-vter and of uneven density; (B) dense . ..jjmks more extensive, better defined mure homogeneous than category A, occupying less than three anterior rib : i.o; -C) similar shadows extending more three anterior rib spaces; and iD) extending more than three ante- r no spaces plus gross distortion of the . onary architecture. i here are two disease hypotheses. The suggest that man's environment differences in the natural history of r.ple and complicated pneumoconiosis. pneumoconiosis only appeared and : .rosed as such in those who were ex- to coal dust. Complicated pneumoappeared and progressed in those .lefr the mine; it did not appear to any . r. nr in those who had less simple pne .....niosis than would be classified in the .;'.d category. 1:; Mirveys on coal miners, McCailum . : lirowne* found in the roentgeno. group that the roentgen evidence j-ncumoconiosis increases in prevalence . :h rising age and with_ length of time ru at facework. Between twenty-six and -rive years of age, nearly 8 per cent *d Minpic*pi*w-i..u-..:ck and the perntage of men affected rose sharply be.,rn rhirty-six and forty-five years of These two age periods correspond - ..iily to from one to ten years and eleven . t enry years at the face. They observed :: rile length of rime at the facework is .re important in producing roentgen i .ns of pneumoconiosis than is the period : ?r::ie working in the pit. These authors ;1\c that the men with pneumonco'tio. . diould be allowed to continue work at : ; race only under medical supervision. Conical scudies53,l,*sl*",n on coal workers in this country continue and in at least two communities,<T iJ the influence of our Eng lish colleagues has become manifest. The use of the "standard sec" of diagnostic roentgenograms is being employed. In studies concerned with the relation ship between tuberculosis and pneumoconio sis in coal miners, Cochrane3 suggests "that a little coal dust retained in the lung has a definite therapeutic effect, whereas larger accumulations increase the attack and mortality rates from tuberculosis." It is felt that with "standard film guides, the roentgenologic diagnosis of tuberculo sis can be made with reasonable consisten cy and that shadows characteristic of tu berculosis can be distinguished in roent genograms from those of simple and com plicated pneumoconiosis. The attack rate of the re-infection type of tuberculosis is found to be related to the severin' of the- associated simple pneumo coniosis50 and is higher than in the general population. It seems to be reduced in cases of complicated pneumoconiosis. For comparative purposes, it is of inter est to note chat Wall,1* in a study of ioo autopsied cases of anrhracosilicosis, found pulmonary tuberculosis in 3 cases, as judged by histopathologic criteria and ex amination for acid-fast bacilli on stained smears. The majority of the patients died of heart disease, with cor pulmonale ac counting for one-half of the cardiac deaths. Pulmonary Function and Roentgenologic Correlation. Gilson and Hugh-Jones,57 in undertook an investigation with rhe object of determining the precise cause of breathlessness in a group of coal workers and relating its severity to the roentgen changes in the lungs. Their results showed that rile main disability from pneumoconi osis, excessive breathlessness on exertion, cannot be distinguished by functional tests from breathlessness caused by chronic non industrial pulmonary disease. This observa tion renders it difficult to allocate in an in dividual the proportion of breathlessness caused by industrial exposure. In England, the National Insurance (In- fcili ' JUti c J^ A- Eugene P. Pendergrass Jir, 19;} dustriai Injuries) Act (1946) attempts to make such an allocation. Under its regula tion there are two separate issues in rela tion to the disability benefit for pneumo coniosis: first, its diagnosis, "has this man got pneumoconiosis within the meaning of the Act?"; secondly, the disability assess ment, "to what extent is the man disabled and what proportion of his disability is due to pneumoconiosis?" Under the Industrial Injuries Act in England, the definition of pneumoconiosis is based on pathology and during life the diagnosis is based on the occupational his tory* and so-called "characteristic" roent gen appearances. Unfortunately, the corre lation between roentgenologic and patho logic findings is not perfect. But, the stud ies of Gilson and Hugh-Jones77 emphasize two aspects concerning the roentgen diag nosis. First, miners with no roentgen evi dence of pneumoconiosis are, on the aver age, as breathless for their age as men with simple pneumoconiosis and more breath less than non-miners, particularly the el derly. This suggested that su^ miners might logically receive benefit for their dis ability. Secondly, functional emphysema, which increases with the ascending roentgenographic categories, is part of the same pathologic process described for pneumo coniosis. Under those circumstances, it is regarded as illogical to give extra disability benefit for "emphysema" to disabled men who have the roentgenographic changes of pneumoconiosis. In simple pneumoconiosis there was no average increase in breathlessness on exer tion with increase in roentgenographic ab normalities. However, there was an in crease in breathlessness normally associ ated wirh age, old men being proportion ately more breathless than young men whatever the degree of change. In complicated pneumoconiosis, the breathlessness was nearly always severe and increased with the roentgenographic changes, and was augmented even more by advancing age than in simple pneumoconi osis. In assessing the extent of disability, it is necessary to consider all disabiiities as thev relate to "loss of health, strength and power to enjoy life." The extent of breathlessness was the main disability to receive Gilson and Hugh-Jones' consideration, and the one which we as radiologists are most con cerned about. Their studies indicated that a combination of the standard exercise test and some determination of the maxi mum ventilatory capacity gave the best objective measure, but that it was prob ably unsuitable for the Pneumoconiosis Panels. Gilson and Hugh-Jones suggest that possibly the simple procedure of meas uring diaphragmatic movement and level is well enough related to maximum ventila tion to allow a reproducible division of sub jects into 4 or 5 grades pertaining to breath lessness. Their most discriminating test permitted the division of range of breath lessness between normal and extreme disa bility into nine steps. These authors indi cated that there are clear differences be tween the average degree of breathlessness for each roentgenographic stage and the normals at the same age. They stated: "This `average' increase of breathlessness at each x-ray stage might justifiably be re garded as that due to pneumoconiosis, and a case could be made out for allotting bene fit for 'disability due to pneumoconiosis' simply upon the x-rav-stage at a given age, and this is the most practicable and logical conclusion to draw from our results."77 The work of Gilson and Hugh-Jones is a magfidiwcii; contribution and goes a long way to show the possibilities in this field. Mobility of Pneumoconiotic Deposits. In 1918, Haythorn37 noted that in an anthracotic lung there was always a large number of free pigment-bearing cells during the early stages of pneumonia. This observa tion, as well as his continuing interest in the subject, was somewhat esoteric to me --a young radiologist, because it was thought to be impossible for one to demon strate the roentgen manifestations of the results of migration of alveolar phagocytes loaded with dust particles. The clinician, *, ''95s' ;>, it !S as they : p<4 r .esst ._i Gilson nd the }St con ed that exercise e maxihe best s probcnniosis suuizest it irseaslevei is ventilaof sub breachng test breathtc disars indi ces belessness nd the stayed: les(^ \ v be resis, and u beneoniosis' -en age. logical ;ults."5T ies is a a long 5 field. -sits. In anrhraaumber ing the bservatrest in : to me it was demon- of the goevtes inician. n> L f $> I5 | 7, % g s n ?> ft* S* ffc"?s. rh* 1ft, ii H ^J .. .... N*o. ! Silicosis and Other Pneumoconioses JO rile other hand, observed rhar the coal iiicr continues to have a black sputum tor _ -tn^ rime after he gives up work in the Such observations, as well as clinical uptuvement of some workers after leavc viuaty occupations are to be regarded as . .liricanr even if one does not become in -oted in basic physiologic processes. 1-drtunateiy, there are investigators44-24 h. do appreciate the need for basic work . ,;n rlie excursionary activity of alveoli, the :Junism by which dust is removed from .firerior of the lung, and the impiica -n* chat such knowledge may contribute living some of the problems of pneumo* " U 1S. I now believe that the radiologist may able to make a minor observation con . -nine the mobility of pneumoconiotic de '.!>, possibly in welders and workers in :icf opaque dusty occupations such as and tin oxide workers. This opinion naval on the observation of a consider . G disappearance of the pattern of hemo- is in mitral heart disease following -'imissurotomy. Follow-up chest roea*. graphic studies on individuals like after they are removed from their exposure, may provide interesting >n what can be expected from the -.uenologic standpoint. SKCMOCONIOSIS AND RHEUMATOID SCI HRIT1S (CAPLAN'S SYNDROME) J:: Caplan8 called attention to an of unusual massive lesions in h...csrof coal miners with rheumatoid -c-.r-.ti?>. He found an increased frequency ::;.i>*.ive lesions in these arthritic per . .uni, in some, the massive lesions were w.:hir in that they were multiple, round, - .brined and distributed rather evenly T-.riumc the lungs. In others, the roent-'-an appearance resembled the usual G,-.c lesions of infective pneumoconio- Hne lesions were not associated with .:::i:rionaI symptoms nor unusual res.r .r\ distress* Caplan does not suggest .il coal miners with pneumoconiosis . -lu-.jmatoid arthritis show a character :i-.*:ugcnologic appearance* . Subsequent to Caplan's observations, others have made additional studies.'53:* Gough, Rivers and Seal55 have reported on the pathologic findings of the lungs of 14 Welsh coal miners with rheumatoid arthri tis and biopsy lung specimens from a addi tional cases. They concluded: "Modules having a distinctive gross appearance cor respond with the radiographic round opaci ties described by Caplan (Fig. 25). These 'rheumatoid' pneumoconiotic nodules con tain necrotic collagen and dust. Tubercu losis was present in several cases. A non specific inflammation was also found. This is believed to be the `rheumatoid' compo nent." MtaU54 has curried out an epidemiologic survey of rheumatic arthritis in a complere community of 9,430 males over fifteen years of age in South Wales and among other things observed that there was a sig nificantly high prevalence of massive fibro sis and tuberculosis among miners with ar thritis. Price and Skelton'5 have described widespread nodular lesions in the lungs of a woman, aged fifty-eight, with rheumatoid arthritis. At necropsy, scattered focal le sions were found in the lung, in which there was an active subacute inflammation of the arteries and bronchioles. The foregoing comments are only a few of the reports relating to some aspect of the possible implication of Caplan's observa tion (Caplan's syndrome). We have not made any particular study or. the subject of rheumatoid arthritis and pneumoconiosis, although we are inter ested in any factor which may have a modi fying influence on the lesions of pneumo coniosis. Therefore, in an informal manner, we have been collecting roentgen studies on individual workers and patients who have rheumatoid arthritis and pneumo coniosis. I am not prepared at this rime to do more than say that 1 have seen roent genograms of individuals exposed to rela tively small amounts of coal dust and silica which demonstrated lesions similar to those described by Caplan and others. In some of the lesions there was evidence of calcium .34 Eugene P. Pendergrass Jmr% t$;> unable to give an opinion on the incidence of carcinoma of the lung. His patients -rr usually referred for definitive therapy anu occasionally for diagnosis. The radiologist is, however, confronted with a diagnostic problem when he makes an examination of the chest of an individual who has silicosis and who has symptoms that may be inter, preted clinically as suspicious of carcinoma. 1 have seen silicotic persons who have had persistent hemoptysis without defini tive lung lesions whicivone wouid interpret as either tuberculosis or carcinoma. Subse quent bronchograms have demonstrated stenosed bronchi and at operation the step- osis was the result of fibrosis and scar con traction and not due to carcinoma. On other occasions, I have seen patients with hemoptysis, unilateral massive lesions, and suspicious Papanicolaou smears. No carci noma was found ar operation. When the silicotic patient has multiple conglomerate lesions with a pattern of nodulation, it is impossible or at least im probable thatone can make a roentgen di agnosis early enough for a curative surgical procedure. If there is any doubt as to the identity of the lesion, one should utilize all diagnostic means, including bronchogra phy, selective angiography, and Papanico- :- -.- --giy -.^ Fig. 25. (</) Caplan's syndrome (coal workers' pneu moconiosis with rheumatoid arthritis) in a iittysix year old individual. This person has been ex posed to coal dust for seven years and he has a well iuou smears. If one is still uncertain, we recommend surgical exploration. We have noted that a number of silicotic patients often are referred directly to the thoracic surgeon with a presumptive diag advanced rheumatoid arr.k4 Th.e/ji^jnosis was made by roentgen examination and has not been confirmed by lung biopsy. (5) Close-up of lesions in the right upper lobe. The lesions look very much like malignant metastatic nodes, but this individ ual has been under observation for some six or nosis of carcinoma of the lung. Thr*** pa tients have frequently been either hard or soft coal miners. In every instance with z exceptions, the roentgen diagnosis has been silicosis with infection. One of the excep seven years and we believe that malignancy can be excluded on the basis that they have not changed in size. tions, diagnosed as carcinoma, showed a narrow and funnel-shaped bronchus sur rounded by a mass. The lesion was a sili deposition. Whether the calcium was re sultant from tuberculosis, histoplasmosis or some other necrotizing process is uncer tain (Fig. 25). cotic mass. The other exception was a lo bar consolidation, typical of atelectasis from a bronchial obstruction. That was a carcinoma. The physician, in any discipline, who is SILICOSIS AND PULMONARY CARCINOMA unfamiliar with some of the vagaries of sili ' The radiologist in a general hospital is cosis and other forms of pneumoconiosis \ . 41 ;a it > hi .4 S'J lL '! !U *. !u (Ii u : it ;<* 4i !! j. it h. .*1 A*. Silicosis and Other Pneumoconioses . ,.ij M-Tiducie that a unilateral congiomer- density in the roentgenogram, rarely, if f ur massive lesion in the absence of a ever, cakes place in cuberculosilicosis. i u.'fcm of nodulation should be regarded Lung lesions which have migrated to the .. ^ivmoma until proved otherwise. That hilt produce shadows that look not unlike t . .p<rdallv true it there is a high index of lymphoblastomas or other mediastinal tu .;>^!on for carcinoma of the lung. I have mors. When dealing with pneumoconiosis, ,;ui luminagraphy most helpful when in one should adhere strictly to a rule of not . ,'m about the nature of a massive lesion giving radiation or chemotherapy for a pre pneumoconiosis. Distortion of bronchi, sumed diagnosis of malignancy. Biopsies deposition, small emphysematous for confirmation of the diagnosis are recom | .-rj> around the lesions, and possibly other mended; otherwise, tremendous damage to I -ill silicotic lesions assist in excluding the tissue might occur. t .Mnnma as the first choice for diagnosis. Under pathologic considerations, com * j iicre are rwo types of carcinoma seen in ment has been made on the incidence of \ .,:.enr.s with silicosis that frequently are carcinoma of the lung among silicotic per Aajnosed. One group includes those sons, but there are several other studies i . jmmis carcinomas which become necro- that should be mentioned. Schoch;i in an f the center, break down and subse- investigation of material from the Swiss ac | . r.'ifly the patient coughs out most of the cident insurance organization found no eti- -.Mm* material leaving a fairly thick- ologic relationship between silicosis and . JL.i. large, oval cavity, which gradually primary carcinoma of the lung. Wall,** in a .'eases in size. One rarely, if ever, finds postmortem study of a series of 100 cases of | .x-fcie bacilli in the sputum. The lesion anthracosilicosis, found 4 cases of primary iv tir may not extend to and destroy the carcinoma of the lung. James-*1 reports that | . .-.*,ent nbs (Fig. 26). Oftentimes, the pa- primary lung carcinoma was found at ne - f .iuc< not complain of much pain, even cropsy in 3.3 per cent of 1,827 South Wales -...h, the ribs are eroded. Because of the coal iners and in 5.4 per cent of 1,531 % cavity and rib erosion and silicosis, South Wales non-miners. In 12, the rumor C :> an unbelievable urge to call such was in the mass, and touching it, in 5. In 7, p Tuberculosis. Tuberculous cavities the tumor was remote. The rumor was sim t, . . fher thin walled or, as so often hap- ilar in the histologic variants, in the age in | . -s. thick walled. The cavity is irregular cidence, and in the distribution of metas- j* . ; rarely larger than 5 to 10 cm. in di tases as that seen in the non-miners. ' g . rfcr. The cavin' noted in primary carci| v.4 ufrhe lung is usually 5 or more cm. in ASBESTOSIS AND PULMONARY CARCINOMA | . -uitef uhen first seen. There is prac- . I personally have not studied any cases | Ji; no reactive lung lesion .^r,\"."d ..t"? of the lung in asbestosis. The I -o file cavin'. - roentgen studies of the cases that I have | n.e >ccnnd group of carcinomas that seen have not been serial studies, but have | i.keiy to be missed includes those that been roentgenograms of advanced lesions, jf ..-..i.-P slowly amid shadows which may. such as atelecrasis of a lobe, a large mass | :.,? been interpreted as due to silicosis adjacent to the hilus or a unilateral lesion . mtecrion. Carcinoma is not suspected . in an upper lobe. Lynch and Pratt-Thom- j : .berculosis is thought to be the pre- as4* indicate that the statistical evidence | ;-live modifying infection. When the for a causal relation between lung carci p nmria has grown large enough, the noma and asbestosis is strong. An opposite g .rn;s i> obstructed and atelectasis opinion is expressed by Jacob and Bohiig.40 place. The atelectasis produces a sud- In Dresden, carcinoma among asbestos | - ;n,reuse in the roentgen manifesta- workers seems to be rare. Four cases of fa ... >mh rapid progression of the shadow tal carcinoma of the lung were found in 339 L L.V- Rri ( a !! u a t: h ci t\ 0/ 0( er C2 ii> ar be ar Fig. 26. (.A) Carcinoma of the left lung in a seventy-^ne year old white man who had been a coal miner for forty yearn. He had been in his usual health except for increasing shortness of breath and chronic cough until November, 1956, when he developed pain in the left side of the chest and hemoptysis. A roent. gen examination on December 27, 3956 showed a large cavity in the upper portion of his lower lobe. I: was thought to be tuberculosis and anthracosincosis. Note that the ribs are not involved. (3) Roentgens gram made in March, 1957. The appearance was essentially the same except that this time the sixth Hi was eroded. (C) Roentgenogram made in July, 1957. The cavity was larger and portions of four ribs wen destroyed. We thought the lesion was a carcinoma which had largely excavated itself. A biopsy confirmee the diagnosis. (D) A slightly oblique roentgenogram shows the wall of the lesion adjacent to the thoracic wall (arrows). he in in in t'es loc WC pn w< fu ilk tr Sc an tar the to cer tee. car ( cat No. i Silicosis and Other Pneumoconioses .s.'nc6W5 workers from 193c to 19*4. Doll,'5 - study of 105 autopsies of asbestos ,...^kers, found 15 carcinomas of the lung jwiciateci with asbestosis. He concludes -:ar lung carcinoma is a specific industrial .,/arJ of certain asbestos workers and that ::u- r.vcrage risk among men employed :-Aenrv years or longer is 10 times that ex : itimced by the general population. I'Sr.UMOCONJOSJS AND PULMONARY CARCINOMA Carcinoma of the lung is a major cause ,ii-arh today; therefore, the relationship : -.avironmentai factors to the etiology of . ..-.a cancer is receiving increasing consid- 'Q. Epidemiologic studies have been ...vied out in many industries, and are sCy to increase, as guide-lines are evolved ..I .1 program of confidence is developed :v.ccn governmental agencies, labor, industry. NUMMARY AND CONCLUSION Pneumoconiosis continues to be a .. ri hazard, national and international _ ;. There are many dedicated individuals -.xnce, in medicine, in organized labor, :-..:u>try, in insurance, in the legal pro*--.!, and in a number of agencies in our .1, state and national governments who ., ..id welcome a united effort to prevent . . ..muccmiosis and its complications. .. L.ws governing work conditions and kmen's compensation have been help .. organized continuing education is to be a better approach in this coun i-.cause, unlike England, we have 48 ' most of which have different codes . : laws. In 1936, the United States Secre. Labor,'Frances Perkins, recognized \wi for an organized educational effort ; r -vuic mdusnrY, labor, medicine, and , .. r.u'.ier.: with an informed opinion con..na xlicosis. After the several commit - rrifc their ^epo^ts47i<il'80<, for pubii- rhe committees were discharged. ; :idit:ons have changed since the publi r. nf the Perkins committees' reports. Many of the industrial processes elaborat ing dust are new. Scientists now believe that submicroscopic dusts should receive major consideration. It may be necessary to re-evaluate the concepts concerning the amounts of dust that constitute safe levels. Methods of dust counting may need revi sion. Development of aerosols for control of dust hazards seems to be increasingly ef fective- There are many, many other phases of this problem which involve careful con sideration by disciplines outside of radi ology, but radiology has an important task to perform. 4. The radiologist plays a major role in the diagnosis of pneumoconiosis in the liv ing individual. He assumes a role of in creasing importance in the estimation of disability* and in the results of rehabilita tion. It Is said that the majority of contro verted compensation cases involve ques tions of fact rather than questions of law.59 Most of the fact cases involve a medical question.39 Some of the questions are: What is the diagnosis? When does the con dition become disabling?*4 When should the employee, subject to exposure, be re moved from his employment?*4 When should such employee be deprived of his privilege of continuing at work in the occupation in which he may be engaged r*4What methods are available to medical sci ence to pronounce that the employee is totally disabled:*4 What sequelae result from a diagnosis of partial disability?*4 Should the employee at that time termi nate his employment:*4 These are some of the imponderables with which the physi cian and the lawyer are faced in their con sideration of pneumoconiosis in an individ ual seeking compensation. It is estimated that workmen's compensation administra tion is about 80 per cent medical.3* The satisfactory operation of the work men's compensation system depends large ly on competent and adequate medi cal treatment of injured employees, the prompt furnishing of accurate medical re ports on injuries and the giving of medical Sit ;7i 'I C 9, Eugene P. Pendergrass J*ar. 19a testimony at hearings on controverted claims. In compensation cases, the physi cian's responsibility is not confined to the patient but extends to the community, in the persons of the members or* the industrial accident commission and to the involved industry.*4 The radiologist will be able to serve the patient and the community bet ter if the profession can agree on guide lines of diagnosis and extent of disability^. This has been done in England and other countries. We should be able to develop working guide-lines for the United States. Guide-lines for diagnosis and disability ul timately would provide essential data for the scientist experimenting with new tech niques for humans and the biometrician analyzing epidemiologic and environmen tal data of communities where there are dust hazards. It would provide information for the State Pneumoconiosis Panels and industri al accident commissioners which should not be susceptible to as much disagree ment amongmedicaj experts as obtains now. Our present method of medical education does not provide for the infplemejitation and the follow-up information that are necessary in controlling pneumoconiosis. Often rimes, medical practice does not keep pace with new and acceptable con cepts, especially, when new data develop within a discipline outside of medicine. 5. Some of the other groups concerned with the problem of pneumoconiosis in clude: the general physician; the internist; the cardiologist, the pulmonary physiolo gist; the allergist; the phthisiologist; the thoracic surgeon; the bronchologist; the physical therapist (rehabilitation); the pa thologist; the experimental pathologist; the public health officers; members of Bureau of Standards; United States Department of Labor; the industrial hygienists; the air pollution engineers (ventilation, aerosols, etc.); the industrial physicians; the psy chiatrist; the representatives of labor, industry and insurance; the lawyers; the physicist; the biometridan; and the toxi cologist. 6. It is suggested that the American Roentgen Ray Sodety initiate through its President and its Executive Council a pro posal that the National Academy of Sci ences request the Committee on Radi* ology of the Division of Medical Sciences of the National Research Council to formu late plans for the inauguration of a National Committee on Pneumoconiosis Protection andjor Control. A prototype of such a com mittee is the National Committee on Radi ation Protection. The National Committee on Radiation Protection is so constituted chat all interested groups are represented. It is a continuing committee which keeps informed on new developments and, with similar committees from other countries, agrees on acceptable methods and stand ards of good practice. Its reports are pub. lished in scientific journals and handbooks and are made available to everyone con cerned. These reports are educational and informative, but are not regulatory. 7. Finally, if we as radiologists will ac cept the challenge presented by the prob lem of pneumoconiosis and do something constructive about it, we can feel assured that the ideals and conquering spirit of Caldwell and other great pioneers, indeed, will continue to live. Department of Radiology Hospital of the University of Pennsylvania Philadelphia 4, Pennsylvania REFERENCES 1. Badham, C. Nui.cs on a fine type of fibrous pneumoconiosis produced by silicates and other minerals. Report of Director General Public Health (New South Wales) for year ended December 3:, 1927, Sydney, Australia, Government Printing Office, 1929. 2. Baroen, R. P. Interpretation of some radiologic signs of abnormal pulmonary function. Radi. 19S^J9, 4.3I-+36. 3. Barden, R. P. Ginical radiology and studies of pulmonary function. Editorial. Am. J. Roentgenol., R.ad. Therapy 6: Nucleai Meo., 1957, 77, 1085-1087. 4. Barden, R. P., and Comroe, J. 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