THE

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RADIOLOGY.*

By MAUalCE R. J. HAYES. N the first place let me assure you of my sincere appreciation of the high honour of being chosen as your President for the coming year. As my introduction to the chair synchronises with the coming into operation of a new regulation which makes instruction in radiology compulsory for all students of medicine, I appreciate the honour all the more deeply, since it comes at the moment when the status of the branch of medicine with which I am so closely identified has been raised to its rightful place in the curriculum. In his original monograph, published in 1895, Roentgen suggested that his discovery might be of aid to surgery. He did not dream of the aid it would be nor of the revolution it would bring about, for it is quite true to say that it has wrought more changes in our concepts of the pathology of the thorax and abdomen, and provided more exact lmowledge of the anatomical relations of the hollow viscera and their motor functions in health and disease than had ever been obtained before. Compared with its sister sciences in the family of medicine it is still in its fascinating age, for its phases of development are by no means exhausted, and it forms a valuable connecting link between the other medical specialities. The birth of this new child in the medical family was not received with universal acclaim. There were many inheritors of the traditional conservatism of our profession who looked askance at this offspring of physics whose advent was unobtrusively announced to an astonished world under the perplexing name of " X." The more enterprising, however, hastened to turn it to good account, and the old prejudices and hostilities were soon dispelled by the successes which followed in the wake of the new method. When we look at the elaborate equipment of a modern x-ray department it is difficult to realise, but salutary to recall, the enormous difficulties which confronted the early radiologists. The primary electrical current was obtained from a few wet storage batteries of limited capacity: the high tension current from a coil with hammer break; the x-ray tubes were of the flimsiest kind, not much larger nor much more durable than a test tube, and almost as cheap. The photographic plate was of the ordinary kind. With such scanty equipment the average length of the exposure required to take a radiogram was about one hour. Nothing was then known of the dangers of prolonged exposure to x-rays, and radiology, like so many other branches of research, has given many hostages to fortune. Indeed one may say that the milestones on the path of its development are tombstones

I

* Being the Inaugural Address delivered at the opening meeting of the Session 1928-29, to the Medical Society, University College, Dublin, November 14th, 1928.

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erected to the memory of those early pioneers. And here I would like to digress for a moment to pay a respectful tribute to the memory to one of Dublin's pioneers who paid dearly for his enthusiasm. Skilful mechanician and craftsman that he was, Lane Joynt became the foster parent of radiology in Dublin. Aiding its growth and development at a time when its dangers were unknown, he bore the consequences with heroic fortitude and without; complaint. He never posed as a martyr. And on recalling those early days Itaughton's work must not be forgotten, for he was one of the first, I believe, to clip a fragment off an ordinary film, wrap it in black paper, and take the first dental radiogram from inside the mouth. We are glad that the Gods did not smite him for his pains. To Lane Joynt and to all like him, from whose sad experiences the later generation of radiologists have profited, we pay respectful homage for the lessons they have taught us. A word of solemn warning to the beginner may not be out of place. It is: Never, whether through curiosity, or to give a demonstration, or for any other purpose, expose your hands to the x-rays. Such foolishness was no doubt responsible for some of the disasters of the past, as well as the practice of viewing the bones of the hand on the screen to see if the tube was working properly. For caution and restraint in this respect many who have been long engaged in the practice of radiology have been amply rewarded. Radiology is sometimes blamed for the disappearance of the skilful diagnostician. So is bacteriology. It is said perhaps truly that there is an increasing tendency to resort to the x-ray department and the laboratory for a diagnosis without having recourse to a systematic routine examination and a careful analysis of symptoms and signs. Both specialities so frequently appear to establish a diagnosis that inspection, palpation, percussion, and auscultation, it is alleged, are becoming a lost art. The radiologist must not be blamed for the introduction of the " ready reckoner " methods in diagnosis. He would, indeed, be greatly relieved if none were referred to him but the essential and the doubtful cases in which the positive or negative results of his investigations might prove helpful in establishing the diagnosis. It would even appear that the distractions of the x-ray department are sometimes availed of to placate discontented patients who may have to wait a day or two in the wards ! If the high standards of diagnosis of the pre-Roentgen era are to be maintained, the obligation devolves on the clinician who must set the example to the student by making full use of all the ordinary means before calling in ancillary methods; the student should remember that when he goes out to practice in a few years hence he must rely on his own resources, and that he must be able to assess proper values to the symptoms and signs, for the services of well-equipped departments will not then be at his disposal. Despite what alluring advertisements say, and the advent of cheap hydro-electric power, the time is very remote when a radiogram can be produced merely by the turning of a switch.

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Radiology is now a highly specialised branch of medicine, and like all these specialities it requires special aptitude and special training. The function of the radiologist is to demonstrate the pathology of the living, and to do this correctly is the aim and object of diagnosis. It is not generally realised, however, that the man who takes up radiology undertakes a very grave responsibility, for there is no department of medicine into which it does not enter. To some, the radiologist is nothing more than a mechanic whose sole function is t o take " photographs," yet there is no field of medicine requiring a more general knowledge than radiology. The radiologist must be a good anatomist and an expert in osteology. He must have a sound knowledge of physiology, pathology, and gynaecology, and he must be very familiar with the clinical aspects of medicine and surgery. Added to this he must have a taste for mechanics, and it is essential that he have an elementary knowledge of theoretical and practical electrical engineering, otherwise it will be impossible for him to get the maximum efficiency from his equipment or to detect faults when they arise. Even yet the multifarious accomplishments of this Robot are not exhausted, for he must be an expert photographer and sometimes a carpenter, for there are few radiologists who have not a piece of home-made apparatus which in their hands serves its particular purpose as nothing else can. Thorax.--Physicians had at first been somewhat slow to recognise the value of x-rays as an aid to the diagnosis of intrathoracic disease, but improved technique and greater experience have greatly enhanced their value. In the thorax as everywhere else the x-ray should not be regarded as a short-cut to an early diagnosis. The information which it gives is but a part of the whole clinical evidence, and its value must be estimated by the skill of the radiologist, his experience, and his ability to interpret the shadows which he finds and to translate them into terms of pathology. Sometimes the radiological findings may be decisive, as, for instance, when the clinical signs are masked by thick layers of muscle or by gross pathological change, but nowhere is the correlation of clinical and radiological evidence more essential than in the diagnosis of thoracic disease, and nowhere is tile problem of accurate diagnosis sometimes more difficult. Change in structure does not always imply change in function, and what one conceives to be " the normal chest " is rarely seen. There is a very wide variation in the amount of hilar shadowing and lung markings in perfectly normal individuals; hence, where the boundaries between the normal and abnormal are so elastic there is ample scope for fallacy, but errors in diagnosis can be reduced to a minimum by prudence and common sense, and by a more thorough appreciation of the possibilities and the limitations in the field of diagnosis by the radiologist and the physician alike. Aneurysm.--The diagnosis of aortic aneurysm is often extremely difficult without the aid of the x-ray, and even with it, it is not always easy. The diagnosis of a saecular aneurysm is

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sometimes certain, more especially when expansile pulsation can be seen, but the differentiation o~ transmitted and expansile pulsation is often exceedingly difficult, and it is sometimes impossible to differentiate aneurysms from solid new growths. Radioscopy is always more valuable than radiography, as much more information can be gained by " screening," than from a radiogram. A description of the routine method of examination by x-rays was published by me sixteen years ago, and it has not altered in any particular since.I

Pulmonary Tube/rculosis.--Apart from the clinical manifestations, the earliest signs of the disease are diminished illumination of the affected area on full inspiration, and restricted or irregular movement of the diaphragm on the affected side. A small, feebly acting and centrally situated heart is always of much significance, as there seems to be an intimate relation between microcardia and the habitus phthisicus. The result of infection may be an exudative broncho-pneumonia, a fibrotie lesion, or complete recovery. In the broncho-pneumonie type the bacilli are lodged in the bases of the alveoli, which consist of endothelial cells and no connective tissue, and the only reaction which can take place is an exudation which appears as a circular sago-grain shadow, with the intensity of the shadow diminishing towards the periphery. If these shadows preponderate the prognosis is bad. In the fibrotic type the bacilli are lodged in the infundibula of the alveoli where there is connective tissue, and the resulting reaction is fibrosis. Here the lesion is a comma-shaped opacity, and if these preponderate the prognosis is good. In the majority of cases both types are present, and the prognosis depends on whichever is in excess. In the third eventuality the lesion first breaks down to form a thin-walled cavity in which calcium in the form of colloid is deposited, and finally calcium phosphate. X-ray examination of the chest is always incomplete without a combination of radioscopy and radiography. The film frequently shews deposits which may be missed on screen examination: it gives more detail, and it can be quietly studied at leisure. It will also direct the attention of the physician to particular areas where suspicious shadows are shewn, and it will serve as a permanent and trustworthy record for future reference and comparison. Radiography almost invariably reveals the extent of the disease to be much greater than was suspected, and where there is clinical evidence of disease in one lung deposits are frequently found bilaterally. While radiography of the chest aids us in forming an intelligent conception of the pathological processes which are taking place during life, and gives information which otherwise could be obtained only in the post-mortem room, and while it is a reliable aid in estimating progress, the final judgment on the activity of a pulmonary lesion must depend on the clinical manifestations of the disease.

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Abdomen.--In opening the discussion on the early recognition of cancer of the stomach at the International Cancer Congress held in London last July, Sir Berkeley Moynihan said that " certainty of diagnosis of gastric carcinoma means improbability of cure. There are no symptoms pathognomonic of carcinoma in any of its stages: the symptoms are only suggestive, not conclusive. . . . . The main inquiry really centres upon the radiologist. He alone, and not always even he, is able to make the diagnosis in the early stages . . . . The radiologist is not infallible, but his approach to accuracy is far greater than that of the clinical physician . . . . "

The introduction of the bismuth meal has been one of the greatest in the many startling advances in radiological science. Indeed it is not exaggerating to say that the whole of our present conception of the motor mechanism of the digestive tract is the result of x-ray revelations, and anatomy and physiology as well as medicine and surgery have all profited by these investigations. If the diagnostic centre of gravity seems to be shifting from the wards and the pathological laboratory to the x-ray department in the recognition of one of the commonest and the most fatal of all abdominal disease, the radiologist, while encouraged by this recognition of his infant science, is all the more conscious of the responsibilities which devolve on him. There are some, however, who seem to think that he is bereft of all sense of proportion and quite incapable of making any save an " x-ray diagnosis." I f the radiologist is to attempt to do his work intelligently he cannot disregard the clinical aspects of the case, but he must endeavour to correlate them with what he finds, and, if he has sufficient data, to affirm a diagnosis. To create a " no man's land " between clinical medicine and radiology is to hinder all progress. The scientific and painstaking radiologist must try to see the clinical perspective in his work equally with the clinician who should endeavour to visualise the radiological perspective when in his judicial capacity he is summing up all the evidences and about to make his final judgment. T h e G a l l - B l a d d e r . - - T h e advent of cholecystography has been of enormous value in the diagnosis of pathological conditions of the gall-bladder. The detection of gallstones by the older methods depended entirely on the technical skill of the operator, and in the most skilful hands a reliable diagnosis was possible only in about 30 per cent. of cases--a percentage so small as to be of little value. This has all been changed by the researches of Graham and his co-workers, who have given us sodium tetraiodophenolphthalein, a drug which is opaque to the x-ray, and whether administered orally or intravenously is excreted into the gall-bladder. In 26 consecutive cases reported by McCoy and Graham2 the cholecystographic diagnoses were colffirmed by operation in 96 per cent. In 212 cases collected from the literature with intravenous administration of the dye the cholecystographic diagnoses were confirmed in 91 per cent. Following the oral administration of the dye the confirmation was more than 80 per cent. This

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method has proved so sucee~ful in detecting gall-bladder disease t h a t it is now universally employed. Urinary Tract.--Less t h a n two years a f t e r R o e n t g e n ' s discovery, articles dealing with the diagnosis of renal calculi b y x-rays began to a p p e a r in medical literature. One of the earliest of these appeared in the Annals of Surgery in August, 1898, f r o m the late Dr. L e o n a r d of P h i l a d e l p h i a and despite the p r i m i t i v e a p p a r a t u s he worked with, his results were reliable. Step by step the technique of r a d i o g r a p h y of the u r i n a r y t r a c t has been elaborated and improved, till it is to-day an indispensable a d j u n c t in genito-urinary diagnosis. N o t alone does it give us accurate i n f o r m a t i o n concerning the size, shape, number, and position of calculi, but by the injection of opaque substances we are enabled to note the size and shape of the renal pelvis and the position of the ureters, and to obtain accurate and reliable information in regard to the pathology of the whole genito-urinary system such as cannot be obtained b y a n y other means. I n the lower u r i n a r y t r a c t the introduction of 20-30 per cent. solution of sodium bromide, or other suitable eontrast material, has been more recently employed by Wideroe and Lofus 8 and Cave and K h o n s t a m 4 to demonstrate the posterior u r e t h r a with the prostate and seminal vesicles, while Stirling, Cohoun, and Rollings 5 declare t h a t c y s t o g r a p h y is more accurate t h a n cystoscopy iu determining the presence and the size of diverticula of the b l a d d e r ; they even u r g e t h a t u r o g r a p h y should precede operation on the u r i n a r y t r a c t as it precludes the possibility of overlooking a stone in the u r e t e r or kidney or in a blind diverticulum.

Gy~wecology.--Radiography has been employed f o r m a n y y e a r s in tile diagnosis of abnormalities of the pelvis. Scientific methods os internal pe]vimetry by means of x-rays have been published b y Thorns s, Roberts 7 and others. A n interesting series of radiograms taken b y me to illustrate the a f t e r results of pubiotomy were published by Tweedy s in 1911. B y x-rays it is possible to differentiate between early or advanced p r e g n a n c y and neoplastic growths, or to determine the normal development of the foetus. B y their use it is possible to ascertain the position of the f~etus, or, as in a case which recently came u n d e r m y notice, to d e t e r m i n e its death. T h r o u g h the courtesy of Dr. P. T. McArdle, Master of the National Lying-inHospital, Dublin, I am p e r m i t t e d to mention two cases. Multipara, age 35; menstruation had ceased eleven months previously. She stated th.at s~e had felt foetal movements up to the eighth mont~b. On oxamination, the abdomen was the size of a full-term pregnancy.. I t was so tenso that the foetal parts could not 'be palpated. Per vagmam a normal uterms was palpatble. Despite the hi.story, and a thorough clinical examination, the diagnosis was obscure. The x-ra~, examination revealed a fully-developed foetus in the fLrsb position witJh the head in the ]eft hypochondrium. The overlapping of the cranial hones w~s very suggestive of a dead foetus. This was removed by operation. It proved to be an extrauterine gestation, and the recovery was uneventful. Primipara, aged 31. History of eleven months' pregnancy. Foetal parts pMp~ble; ~-ray exaanination shewed the ~bone~s of the trunk and limbs, but no head. The patient was delivered of an anencephalic foetus.

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According to Jungmann and Martin 9 it is possible to obtain shadows of the foetus in utero from the eighth to the ninth week onwards, and they claim that the Roentgen diagnosis can be made long before other definite signs are evident. Although ossific centres have been detected in the clavicle and the mandible as early as the seventh week, the recognition of the foetal bones in utero in the early stages of gestation is extremely difficult, because they are obscured by the maternal tissues and the liquor amnii. While in exceptional cases and with the most modem equipment and perfect technique it may be possible to demonstrate the foetus at the tenth week, Darland and ttubney 1~ of the Post-Graduate Medical School, Chicago, say that exceptionally embryonic parts may be seen as early as three or three and a half months, and almost always at the fourth month, but the shadows are so delicate that only very accurate technique will ensure good results. The most recent addition to gyn~ecological diagnosis is the employment of lipiodol for radiography of the uterine cavity and tubes. Those who have employed it declare that the procedure is safe. Its most valuable use is for the detection of occlusion of the Fallopian tubes and the localisation of the site of obstruction. Jarcho n states that the method gives exact information that can be obtained by no other means, and he suggests that the injection of iodized oil may have definite therapeutic advantages in subacute and chronic conditions of the Fallopian tubes.

Op.hthalmology.--In ophthalmology x-rays are chiefly employed for the localisation of foreign bodies in the eye--one of the most ~nxious, most exacting, and most difficult of all the varied tasks of the radiologist. The foreign body may sometimes be so small as to be scarcely recognisable. I recall such a case which I saw in France during the War, in which the small fragment of metal could be seen on the negatives only with the aid of a magnifying lens. It was a minute piece of brass fused to a splinter of aluminium; both were non-magnetic, and aluminium is not opaque to the x-rays. In eye localisation where the foreign body may be so small, and the difference of a mfilimetre in the estimation of its depth may mean the sacrifice or the saving of the eye, there must be no place for doubt or even approximate measurements, and the technique must be perfect. It will not suffice to locate the foreign body inside or outside the globe. Its exact position must be determined. This is now possible in the vast majority of cases, but it cannot be accomplished without practice and experience. A patient who was referred to me recently for the localisation of a shot pellet in his orbit presented me with a pair of films which were taken at right angles. He stated that they were the eleventh and best attempt at localisation. If he had told me that they were photographs of Ireland's Eye I would have been as ready to believe him. The futility, if not the iniquity, of anyone not possessing even an elementary knowledge of radiography attempting work of this kind cannot be condemned too severely. The right-angled method in ophthalmological localisation is hopelessly

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inaccurate, and to make twenty-two exposures, as must have been done in this case, at very short intervals, is little less than criminal when one considers the grave risk to the patient of a serious x-ray burn.

Laryngology.--In laryngology, rhinology and otology x-rays give very helpful information concerning thepathology of all the accessary nasal sinuses and mastoid air cells. Even Wharton's and Stenson's ducts have recently been radiographed after injection of opaque media. 12 Anatomically, the oesophagus is part of the digestive tract, but it is within the province of the laryngologist, and in the diagnosis of diseases of the gullet x-rays are always helpful. Dentistry.--The rSle of radiography in the diagnosis of focal sepsis is well known, and the pathology of dental roots is no longer hidden from us. The teeth may be firm and the gums may appear healthy, yet an x-ray examination may reveal apical abscesses, periodontitis, or sclerosis oi the surrounding bone, all of which are tox~emic factories. The pathology of the root and its socket is not unlike the pathology of bones~and joints, and the degree of infection is very often in direct proportion to the number of teeth affected and the extent of the involvement. In determining the position of irregularly placed or unerupted teeth x-rays are invaluable, and in such cases the diagnosis cannot be established by any other means. Radiotherapy.--Soon after their discovery it was noticed that prolonged exposure to x-rays caused erythema and ulceration of the skin, and Schiff and Freund immediately began to study this biological reaction and to apply the rays in the treatment of various cutaneous diseases. Some over-zealous members of the medical profession, ever ready to welcome a novelty, began to make exaggerated claims for the new remedy and hailed it as a cure for cancer. After a period of boom and unworthy exploitation, during which many patients were injured, radiotherapy fell into disrepute. We are passing through a similar phase to-day, except that the ultra-violet maniacs are more numerous than the radiomaniacs of twenty years ago. Those familiar with the immediate and remote effects of radiotherapy may well be alarmed at the evil consequences which may follow the indiscriminate employment of ultra-violet treatment as practised to-day. The first considerations in the administrations of any therapeutic agent are its quality, its dose, and an accurate knowledge of its effects. Applying these principles to radiant energy our knowledge of it is as yet imperfect and incomplete: we are still in the experimental stage and our work is partly scientific and partly empirical. All that we know of qualitative and quantitative measurements has been derived from the physical laboratory. Careful research has rescued radiotherapy from the limbo of charlatanism, and enduring confidence will be restored provided the unscrupulous and the zealots can be restrained. If the history

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of medicine during the past fifty years is reviewed and one asks what progress has been made in the treatment of cancer?" the answer must be " very little." Halstcad's classical operation for amputation of the breast and Wertheim's for removal of the uterus are the chief contributions of surgery. The combined efforts of medicine and biochemistry have been directed towards the earlier recognition of the disease. The contribution of radiology has been two-fold, firstly in regard to early recognition, and secondly in regard to control of the disease. Many cases of cure are on record, if freedom from recurrence for five or even ten years may be regarded as cure. Some, if not all, of these were surgical rejects, and unfit for operation from anatomical or other considerations, so that it cannot be argued that they would have been just as well if they had not had radiotherapy. Setting aside the question of cure, many cancer patients live longer and lead more comfortable and more useful lives as a result of radiation than they could possibly have lived without it; not only is this true, but the progress of radiation treatment has been so certain that at the recent International Cancer Congress it was advocated in preference to all other therapeutic measures in the treatment of oral and uterine carcinoma. In the treatment of oral carcinoma Dr. Cade said that radium was in his view the only method which combined safety with the best results and without mutilation, and that when the correct technique became established it would gradually supersede surgery. Similar views were expressed by other speakers, and the consensus of opinion was that the prospects of cure by radium were far better than by the older method of surgical excision. I n the discussion oll the relative values of surgery and radiation in cancer of the uterus, Dr. Donaldson stated from a review of published statistics, and from his own personal experience of cases treated at St. Bartholomew's Hospital, from a purely statistical point of view the two treatments are equally efficaeioum in patients who are seen when the disease is still in an " operable " stage. In contrasting radiotherapy with surgery Donaldson very wisely emphasised the fact that because the initial mortality with the former is practically nil it must not be assumed that it is easier of accomplishment than surgery; he severely condemned the promiscuous employment of radium by those who had no knowledge of the theory or the physics of radiotherapy, declaring that it behoves all members of the profession who are beginning this subject to learn everything they can, not only from the results of other people's work, but also of the theoretical side, before starting to treat patients. It is surprising that patients suffering from malignant disease are not considered in the same light as those about to undergo a major surgical operation. The preliminary preparation as well as the fore- and after-treatment are of equal importance. In order to obtain the best result the general physical condition of the patient must be as good as possible, and every means should "

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be employed to increase the general resistance to the disease by the elimination of toxins, by" suitable diet and rest, and by specific measures directed to the local condition, and to combat the ill effects of the treatment. In the consideration of the treatment of malignant disease we must get away from the idea that the local treatment alone is of importance. Radiation does not cure cancer merely by destroying the cancer cells. The fundamental basis of radiotherapy is to administer a does of radiation which impairs the vitality of the neoplastic cells and stimulates the normal connective tissue cells. If this dose is too great the healthy tissues are paralysed and are rendered incapable of resistance; if it is too small the reparative process is too feeble to overcome the reproducing power of the turnout cells. The optimum effect is obtained by that dose which inhibits the growth of the neoplastic cells and stimulates a reaction in the healthy tissues; it is this reaction which is the important factor in the cure, and it should not be impaired or depressed by over-dosage. Our chief aim is to assist nature to repair by impairing the vitality of the malignant cells and by increasing the vitality of the normal structures. Hence the general physical condition of the patient is of paramount importance, and advanced cachexia, severe anaemia, wide dissemination of the disease, or advanced toxmmia are contra-indications to treatment. T h e records of successful treatment of many diseases of a nonlaalignant character, such as exopthalmic goitre, spleno-medullary lcukaemia, Hodgkin's disease, cervical adenitis, and prostatic hypertrophy, which abound in the literature, are convincing proof of the efficacy of irradiation in the treatment of these maladies. My personal experiences have been already recorded38

Teaching.--The ramifications of radiology in medicine are now so widespread and its importance is so generally recognised that in all countries the question of instruction is becoming more urgent. In very many of the recent public appointment~ advertised in this country certificates of proficiency are required and the question arises as to how these demands can be met. It seems that this question must be considered from two aspects : - I. The provision of proper training for students in conformity with the regulations of the General Medical Council and as regards the standard of knowledge he should have to fit him for general practice. II. Post-graduate instruction for those requiring more special knowledge and practical experience to enable them to fill posts in hospitals or public institutions where practical x-ray work forms part of the duty which they may be required to undertake. The student's first acquaintance with radiation takes place

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during his course of physics in the first year. Here he should become very familiar with elementary principles, with the different forms of radiation and how they are produced, e.g., the x and ultra-violet rays, and the radiations emitted from radium and radio-active substances. During his anatomical course, the reading of radiographic illustrations of bones and joints would form the groundwork of interpretation of films. Films illustrating the growth of bone, the epiphyseal centres, supernumerary bones and stereoscopic studies of the cranium would be of invaluable aid. Stereoscopic views of the thorax taken after injection of the cadaver with opaque media would give a mental conception of the pulmonary circulation and the position of the bronchi such as could not be obtained in any other way. Similarly with the cerebral circulation. Radiographic illustrations of the digestive tract showing the actual positions of the various organs in the erect and recumbent positions during life would, I suggest, be most helpful in the study of the anatomy of the abdomen. There are many applications of this method of direct teaching which will readily suggest themselves. No student of physiology needs to be reminded of what radiology has done to advance our knowledge of that subject: The work of Cannon alone on the motor mechanism of digestion is epoch-making. Here also radiographic and cinematographic illustrations would be an invaluable aid to students. During his courses of instruction in the theory and practice of medicine and surgery the student has many opportunities of studying radiograms. The films which he sees in the wards, however, are shown to illustrate pathological conditions and abnormalities of various kinds, but the full significance of abnormalities cannot be understood without a thorough appreciation of the normal, and this must be learnt from anatomy. The microscope and the x-ray tube have become a most important combination in the study of the pathology of bone. There are many infective and neoplastic diseases of bone which have very definite radiographic characteristics, and in most of them a good radiogram will establish an absolute and unequivocal diagnosis. The importance of this when the saving of a life or a limb is in question cannot be over-estimated. In the vast majority of osseous new growths bioscopy is very undesirable, because it frequently causes rapid dissemination and jeopardises all prospect of amelioration or cure by radiotherapy. Indeed one may eve~ postulate that no suspected case of bone sarcoma should be cut into with a view to excising a portion for microscopy. The response to in'adiation will soon confirm the diagnosis, and will do so without gravely affecting the prognosis. I have seen a young man condemned to excision through the hip joint. The ambiguous clinical manifestations of sarcoma in his case had been " confirmed " by a badly taken radiogram in

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which one of the condyles of the femur was mistaken for an abnormal growth of bone. His leg was not amputated. This is an extreme case, no doubt, but it serves to illustrate my thesis, which is the necessity for better acquaintance with a subject on which very grave decisions affecting the welfare of our patients a n d the good name of our profession so frequently depend. I n England a course of six lectures is given to medical students in the fifth year; a similar course is given in University College, Dublin. In the U.S.A. the instruction is more thorough. At the International Radiological Congress held in Stockholm last August Dr. P. M. Hickey stated that a course of thirty hours' lectures was given to students of the third year, and that thirtynine out of fifty-three anatomists in the United States use x-rays in the teaching of anatomy. As regards post-graduate instruction, the Universities of Cambridge, Liverpool, and Edinburgh grant diplomas in radiology. The examination consists in Part 1 Physics and Electrotechnics, and Part 2 Radiology and Electrology. Course~ of lectures for each section, which do not run concurrently, extend over a period of six months. Since certificates of proficiency in radiology have become essential for candidates for certain appointments at home I am frequently asked if it would be possible to acquire the requisite knowledge in a fortnight. It would not, any more th~n it would be possible to become proficient in any other special branch in such a short space of time. The issuing of certificates of proficiency after brief periods of instruction is to be deplored. I have seen such a certificate issued by the medical officer of a County Home who himself never had any practical training in radiology. It is very important that henceforth adequate instruction should be given in this new subject to keep pace with progress and to maintain the traditional high standards of efficiency of our Dublin School. The nineteenth century has seen many notable developments in medicine. Roentgen's discovery towards the close of that eventful epoch was a fitting corollary to what Simpson, Pasteur, and Lister had accomplished some years earlier, and his name will be enshrined with theirs amongst the great benefactors of mankind. A comparison of the treatment of the injured in 1870-71 with that of 1914-18 will confirm the truth of this statement, and apart altogether from the boon which x-rays have been in our time it is only those who were engaged in the practice of medicine in the pre-Roentgen days who can realise how profoundly his discovery has altered our conceptions of the physiology and pathology of the living. " Withal," as Sir Thomas Horder 14 very truly says, " our present notions of disease, even when we think them complete, are probably extremely crude. It is pathology that links together our diverse interests, and we must never lose sight of the essential unity of the pathological processes. Though clinical medicine may see one aspect of disease and radiology

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another, and morbid anatomy a third, and parasitology a fourth, the disease is one and the same, and our best conception of it is obtained, not by undue insistence on any one of these aspects, but by a proportionate mingling of the pictures presented by all. He who achieves the most complete conception of a disease in his mind is the most likely to envisage the appropriate treatment and to get the best results." References. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.

Dublin Jl. ~$led. Science, April, 1912. Jl. Am. M. Ass., June, 1926, lxxxvi, p. 1899-1902. Acta Radiol, 1927, 563. Br. J1. Radiol., xxx, No. 297, p. 121. Anls. S~rg., May, 1928, Ixxxvi, p. 742. J1. Am. Med. Ass., July, 1925. Br. J1. Radiol., xxxii, No. 318, June, 1927. Medical Annual, 1911, p. 537. Fortschr. a.d. Geb. d. Roentgenst~ahlen, 1927, xxxv, 913. The X-ray i~ Embryology and Obstetrics, H. Kimpton, 1926, p. 267. S~rg. Gyncec. and Obstet., June, 1928, xlvi, 725. Presse Mddicale, 1926, 75, p. 1188. Med. Press and Circ., June, 22 and 29, 1927. Br. J1. Rad., xx, Rent. Soc., Sec. 81, Oct., 1924, p. 162.

B R I T I S H STANDARD SPECIFICATION FOR T H E ELECTRICAL PERFORMANCE OF TRANSFORMERS FOR X - R A Y PURPOSES (No. 326-1928). This new British Standard Specification is the first to be issued dealing with z-ray apparatus. I t applies to the main high-tension transformers of z-ray installations, the subject being dealt with along lines very similar to the British Standard Specification for the electrical performance of transformers for power and lighting. I n view of the special requirements, however, of ~-ray transformers, to meet the service conditions associated with ~-ray work~ this new specification differs from the specification for power transformers in a number of important particulars. The most important feature is the definition of the rating of the transformer, this being in terms of the R.M.S. milliampere output when the rated peak voltage is being produced across the terminals. The usual method of expressing the output of a transformer in kVA is thus departed from, the reason being that the intensity of the z-ray cl:t~ut is dependent upon the peak voltage rather than the R.M.S. voltage. The R.M.S. value of the current output is retained, however, as it is this value which determines their internal heating. I n addition to the rating, the specification deals with the types of cooling, standard sizes, primary voltage, regulation, etc., limits of temperature-rise, and the quality of the insulating oil. The tests to be applied to the transformer are also included, one of. which, viz., the switching test, is of special importance in the case of ~-ray transformers. The method of testing the output of ~-ray transformers is given special attention, and the specification concludes with some notes on rectification, these notes emphasising the fact that the type of rectification employed determines the maximum tube current that can safely be obtained without exceeding the maximum output of the transformer.