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A SHORT HISTORY OF RADIOLOGICAL PROTECTION
The origins of x-rays and radioactivity are linked: Roentgen discovered x-rays in 1895 and Becquerel stumbled upon radioactivity the following year while investigating Rontgen’s discovery. In different ways they would transform diagnostic and therapeutic medicine. However both of them brought a risk that would remain an enigma for the best part of a century (at least). That of radiation.
Roentgen revealed his discovery in the very last days of 1895 and within a few weeks radiographs had been taken around the world. Within a year there were 50 books and pamphlets on x-rays and nearly 1000 papers were published, tubes had been improved by the addition of anodes, the fluoroscope had been invented and widely used and General Electric had produced a catalogue of ready-made x-ray equipment. Soon enough, hospitals around the world were setting up departments for both diagnostic and therapeutic use of the new technology.
In the first year there were already hints of future problems. Several workers experienced effects that looked like sunburn with loss of skin and hair from affected regions. At first people blamed the high voltage power supplies and the ozone they created, the processing chemicals and almost anything but the magical rays themselves. However by September 1896 the great Lord Lister, could speak of the “aggravated sunburn” and speculate that “ a transmission of the rays through the human body may be not altogether a matter of indifference to internal organs…”
Within just a few years it became clear that prolonged exposure to the rays could have devastating consequences: sunburn turned into painful sores and warts, necrosis and a variety of cancers. The pain was “as if bones were being gnawed away by rats” someone said. Fingers were amputated, then arms. Pioneers began to die.
The warnings were heeded by some who shielded the tubes with lead and abandoned the common practice of putting their hands between the tube and a fluoroscope to check that things were working properly. By about 1910 it was fairly widely recognised that there was a problem that had to be addressed but another decade passed before there was real consensus and general action. The early protection measures were very practical: shield the tube, wear protective equipment, limit exposure by making adjustments from a protected place, limit working hours and encourage staff to spend time outdoors when they could.
A principle emerged: the deadly effects were a direct result of the traumatic tissue damage so if there was no tissue damage there would be no deadly effects. It was therefore thought that, if the dose was well below one which would result in erythema, there would be no long- term effects. This was the “tolerance dose”. In the mid-1920s a popular suggestion for a tolerance dose was about 10% of an erythema dose a year. When expressed in roentgens (r)in the early 1930s, this became 0.2 r per day and fairly quickly this was reduced to 0.1r per day. This value was the one widely used right up to the end of the 1940s.
However by then questions had begun to be asked about the principle itself based on some discoveries in genetics.
Gregor Mendel had established the theoretical existence of the genes in the 1860s with his famous experiments with peas (although the work was forgotten until the beginning of the 20th century). He had no idea where the genes were. However by the time science had rediscovered his work it was fairly clear that the nucleus of the cell played a key role in inheritance. By 1903 it was plausible that Mendel’s genes were located on the chromosomes and by 1916 that was a widely-shared view. This was largely due to the work of TH Morgan and his proteges at Columbia University in New York with the fruit fly Drosophila melanogaster. This minute creature with its modest maintenance requirements and rapid and productive sexual cycle meant that experiments like Mendel’s could be repeated in fraction of the time in a room of fly-filled phials loaded with bananas to sustain the creature. Morgan and his men tracked natural mutations ( first was a white variant of the normal red eye) and, in a long and clever series of experiments, they were able to map the mutated genes responsible onto the fly’s chromosomes the genes became real.
Hermann Muller, one of Morgan’s students, had a particular interest in how the natural mutations arose and developed an elegant technique to measure the rate at which they occurred. His first results showed a temperature dependence so, knowing that chromosomes were visibly damaged by radiation, he set about seeing how the mutation rate was affected by it. He didn’t have to wait long to find an answer: one of his first experiments in 1926 showed that an x-ray radiation dose of 1000r of x-rays to a fly’’s sperm increased the mutation rate 1000-fold.
The artificial mutations behaved just like the natural ones and, disturbingly, their creation rate increased linearly with radiation dose – without any threshold. Muller was a life-long eugenicist (although by most standards a fairly gentle one) and quickly realised the possible implications of this for the human gene pool. He spent the rest of his turbulent life campaigning for recognition of the threat.
The 1940s brought a new and awesome radiological threat with the development of the atom bomb and the terrible carnage it wrought in Japan. People soon realised that, while this had been far away, bombs were being exploded in America itself – as well as the South Pacific and Australia – in atomic tests aimed at creating even more powerful and terrifying weapons. These tests produced fallout (by now everyone knew about fallout) which swept around the world and this inevitably led to radiation exposure and this led, there being no threshold, to damage to the human gene pool.
The threat to mankind’s genes seemed ever greater. Scientists had models to enable them to make assessment of doses to the gonads and this for a while became the dominant parameter in radiation protection – largely because it was agreed that there was no threshold. Public concern about the long-term genetic effects of atomic tests was a reason why they were banned – although, more cynically, there was a sense in which the developers had gathered all the data they needed.
The threshold principle for somatic effects (those that occurred in the exposed individual) held sway through most of the 1940s but it began to be questioned – largely because it was so at variance with the established no-threshold nature of the genetic ones. So it was one of the issues in people’s minds when the Atomic Bomb Casualty Commission was set up in 1947 to study the survivors of Hiroshima and Nagasaki.
Two results of the early studies rather surprised workers: no genuine genetic effects could be found (they never were) but there was a dramatic increase in leukaemia cases and the incidence of these increased the closer you got to ground zero.
The leukaemia occurrence continued to grow but peaked in the early 1950s and then slowly declined reaching background levels in Nagasaki in about 1980.The story with solid cancers was rather different and more alarming. They were slower to appear but the incidence then stayed at a high level for much longer.
The implications of the data could not be fully realised until there were reliable estimates of the doses received by the survivors. The first of these came in 1965 and these were revised in 1986 and then again, but only slightly, in 2004.
The relationship between cancer effects and doses implied by the Japanese casualty data was regularly reviewed by the UN Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). While risk estimates were modified somewhat over the years there has never been any generally-accepted evidence to support a dose threshold for cancer induction – aligning the somatic and genetic effects. In its milestone report of 1977 (ICRP 26), when the International Commission on Radiological Protection first took full account of the available Japanese data, they opted for a no-threshold proportional relationship for both. By then it was pretty clear that the genetic effects were not the dominant effects in most circumstances, it was cancers that were.
ICRP 26 generated a protection scheme based on avoiding radiation exposures altogether unless there was a clear benefit from the activity and then optimising the exposure by increasing the protection until the cost of increasing it further was disproportionate to the dose savings. This was the As Low as Reasonably Achievable principle.
There were many technical follow-ups to the document that clarified, for example, how the risks from exposure of particular organs could be taken into account (something that was important for internal dosimetry). Applications in many fields – including medicine – have been considered in detail in ICRP reports. These reflect changes in technologies such as dosimetry techniques and new data on risks. However, the core precautionary principles have hardly changed over the subsequent four decades.
18 July 2021
This article first appeared in the Royal College of Radiologists Newsletter.
Geoff is Honorary Secretary and a Trustee of the British Society for the History of Radiology. Most of his career was spent with the United Kingdom Atomic Energy Authority and its descendants working on radiological protection. He was editor of the Journal of Radiological Protection for five years in the 1990s. Since retirement he has written two books on radiological themes: Taming the Rays (a history of radiological protection) and Genes, Flies, Bombs and a Better Life (a biography of Hermann Muller).
- Category: Uncategorised
This area Celebrates the 50th anniversary of the first clinical CT scan of a Patient on 1st October 1971.
It is difficult for anyone today to realise what imaging and diagnosis was like 50 years ago.
In the 1960s imaging was largely x-ray film based and diagnosis depended largely upon the skill and interpretation of the radiologist. Relatively little had changed since the original discovery of X-rays by Roentgen in 1895, until the early 1970s.
The first clinical CT scan of a patient was taken on 1 October 1971 at Atkinson Morley Hospital, in Wimbledon, South London. The first patient image scan 200.2A showed a circular cystic tumour in the frontal lobe. The surgeon who subsequently operated on this patient reported that the tumour was exactly where it was shown on the first scan.
Little did anyone realise at the time just how much of an impact the invention of CT scanning would have on the Medical Imaging world and on all of Medicine and Surgery.
Radiotherapy is the branch of medicine that deals with treatment using radiation. Soon after the discovery of x-rays in 1895 it became apparent that X-rays were able to cause ulcers and damage to the skin. This led practitioners to using this new form of therapy for the treatment of superficial growths. The first person to apply radiation therapy was Leopold Freund in Vienna in 1896. He wrote the first book on radiotherapy in 1903. In France Despeignes in 1896 used x-ray treatment to treat a patient with stomach cancer. X-ray treatments became popular for treating unwanted hair, skin cancers, lupus vulgaris and epitheliomas .
In 1898 the Curies discovered radium and this was subsequently used as a formal therapy. Becquerel who discovered radioactivity in 1896 and shared the 1903 Nobel Prize in Physics with the Curies was another pioneer in this field. Radium which is radioactive was commonly used in bath salts and became a common cure for ailments such as arthritis and gout.
X-ray treatments were even applied in leukaemia notably by Ironside Bruce in the UK who became a radiation martyr himself.
In 1922 at the Curie Institute a French radiologist called Henry Coutard showed that fractionated treatment of x-rays could cure cancer .This was the beginning of early modern radiotherapy.The early pioneers in Britain of radiotherapy included the famous Neville Finzi radiotherapist at Saint Bartholomew’s hospital,London who treated Sigmund Freud’s cancer.
In the early days radiologists were involved in radiation treatment in addition to diagnostic radiology. Gradually from the 1930s onwards radiotherapy developed as a separate discipline breaking away from radiology which concentrated on using x-rays for a purely diagnostic purpose.
Following the discovery of linear accelerators high-voltage external-beam radiotherapy was introduced into medical practice in the 1950’s.
B Thomas A M K Banerjee AK The History of Radiology, OUP, May 2013
J An Overview on Radiotherapy: From Its History to Its Current Applications in Dermatology, Serena Gianfaldoni, Roberto Gianfaldoni, Uwe Wollina, Jacopo Lotti, Georgi Tchernev,and Torello Lotti, Open Access Maced J Med Sci. 2017 Jul 25; 5(4): 521–525
| Radiation_therapy --Wikipedia
These items have been transferred from the Home page and elsewhere and are available through the search function. Some are referenced on other pages.
Links in the archive section are not regularly checked.
Archived 22 December 2021
Report on the British Society for the History of Radiology Annual lecture 2021
The video of the complete lecture is now available on Youtube. Click here to watch.
By Dr Arpan K Banerjee Past Chair and current trustee BSHR
Due to the current Covid pandemic this year’s annual lecture was delivered as a virtual event on Monday 8 Feb 2021. Dr Uwe Busch a distinguished radiology historian , author and the current director of the Rontgen Museum in Remscheid – Lennep , Germany delivered a talk entitled ‘New results on biographical research on W C Rontgen’ .
The first half of the talk was devoted to the Rontgen family tree and we learnt about his ancestors who were successful cloth merchants. Lennep was a small town whose history goes back to the 12 th century and many were farmers in this Bergishland region and then worked in the cloth trade before industrialisation occurred. We were given a detailed review of Rontgen’s lineage. Rontgen was born in the house bought by his grandfather which today has been preserved for posterity.
In the second half of the talk research from Rontgen’s estate and collections in the Rontgen museum were presented. Rontgen left behind over 1800 letters and documents as well as around 2000 glass plates. Of particular interest was his first paper on X-Rays and the people he sent this paper to which included the great and the good of the physicists of his era. In the UK, Arthur Schuster from Manchester and Lord Rayleigh and J J Thompson ( discoverer of the electron ) at Cambridge and Lord Kelvin in Glasgow were all on his list of recipients.
This section of the talk also covered his marriage to Bertha and included illustrations from Rontgen’s extensive photograph collection. Photography was a major hobby of Rontgen’s and the pictures of old Wurzburg which were shown to the audience were a wonderful evocation of what the place was like in his era.
The lecture was well received by the virtual on line audience and Dr Busch was thanked for his wonderful, scholarly informative presentation.
Archived 3 August 2021
BBC World Service Forum 3 June 2021 -- X-rays: New ways of seeing
The discovery of X-rays by the German scientist Wilhelm Roentgen in 1895 was nothing short of ground-breaking, opening up a new era in medicine. For the first time, doctors could see inside the human body without the need for surgery, and diagnose many more living patients.
X-rays had major implications for physics as well, allowing scientists to study the structure and arrangement of molecules. Within wider society, they inspired artists to explore what these new rays could tell us about the representation of reality. It wasn’t long before X-rays were being used to scan baggage, in airport security and even in shoe shops to measure feet before exposure to radiation was properly understood. Huge strides in X-ray technology have given us the type of modern scans that are used today to detect conditions such as cancer.
Joining Bridget Kendall are Drs Adrian Thomas and Arpan Banerjee, both radiologists who’ve collaborated on publications about the history of X-rays, and artist Susan Aldworth who’s used brain scans in her work to investigate the nature of identity.
Listen to the recording at https://www.bbc.co.uk/programm
The British Society for the History of Medicine Biennial Congress -- archived 31/5/21
Diamond Building – The University of Sheffield
Wednesday 15th - Saturday 18th September 2021
History of Medicine in the Workplace
History of Pandemics
History of Nursing
Innovation in Medical Engineering
Abstract submissions on these themes and General Topics are welcome. The closing date for receipt of abstracts is the 31st May 2021. If research has been delayed owing to restricted access to libraries, archives or other resources, this may be stated in abstract submissions where relevant.
For Congress information and booklet, registration, abstract submission and accommodation please go to https://bshm.org.uk/congress-2021/
WEBINAR THURSDAY 2 JULY 2020 -- archived 26/5/21
Presentations selected from the submitted abstracts on the history of imaging(click title for slides):
History and evolution of Artificial Intelligence -
Early chest radiology pioneers and the beginnings of chest radiology -
Miss Marion Frank (1920 -
Kathleen Clara Clark (1896-
RECENT INTEREST archived 26/5/21
Francis Duck. Scope 29(2) Summer 2020. 32–35 ‘The Radium Boss -
Edwin Aird. Scope 29(3) Autumn 2020. 22-
Past issues of SCOPE have featured several other articles of interest. These issues may be browsed free through this link
Ultrasound is a medical imaging technique which enables doctors to both visualise the internal structures of the body and can also be used for therapy.
Ultrasound does not involve X-rays. The technique involves using transducers with piezoelectric crystals which produce high-frequency soundwaves which, when applied to the body, send focussed pulses of sound waves to the internal tissues and organs These waves are reflected back to the transducer and the received data converted into images for diagnostic purposes. The investigation is done in real time.
Ultrasound imaging is used in the abdomen to visualise the abdominal structures such as the kidneys , liver and spleen. It is very useful in the assessment of the uterus and especially a developing foetus in obstetric practice. It can also visualise superficial structures such as the thyroid gland , muscles and tendons and the breast. Ultrasound does not pass through air and hence cannot be used to visualise the lungs easily. It does not pass through bone easily either and therefore intracranial structures in adults are difficult to visualise using this technique. Vascular structures such as arteries and veins are well demonstrated.
Ultrasound can be used to guide medical procedures such as biopsies of tissues.
In the heart, ultrasound can demonstrate the cardiac structures and this application is known as echocardiography.
Not all ultrasound examinations are performed by doctors. In the UK radiographers and technicians who perform ultrasound are known as sonographers. In other parts of the world they are known as radiology technicians.
Pioneers include John Wild who first used ultrasound in 1949 for measuring bowel wall thickness in the USA, Edler the Swedish cardiologist who used it in 1953 in Lund and Holmes et al in USA in 1962.
Ian Donald a Scottish obstetrician working in Glasgow was a pioneer of the applications of this technique. With the physicist Tom Brown, Donald created one of the early machines to perform ultrasound resulting in a very important paper in the Lancet in 1958 ‘Investigation of abdominal masses by pulsed ultrasound’.
W A History of Medical Ultrasound, Francis Duck, 2021
W Articles from Medical Physics International:
W The British Medical Ultrasound Society have a page on history, and their historical collection: https://www.bmus.org/for-patients/history-of-ultrasound/
W A history of ultrasound in gynaecology and obstetrics, which includes a great deal of detail on the older developments: https://www.ob-ultrasound.net/history1.html
B Thomas AMK Banerjee A K Busch U, Classic papers in modern diagnostic radiology, Springer Verlag, Berlin, NY. 2005 ISBN 3540219277
B Thomas A M K Banerjee AK The History of Radiology, OUP, May 2013
J Donald I Mac Vicar J Brown T.G 1958 Investigation of abdominal masses by pulsed ultrasound Lancet 271 1188-95
|Sonographer_doing_pediatric_echocardiography -- Wikipedia|