CONCISE HISTORY OF RAYS IN
discovery of x-rays by Roentgen in 1895 was
the culmination of centuries of observation and experimentation in electricity and magnetism
More than 2500 years ago, the Greeks observed the
analogy of the effect of friction causing amber (that is electron) to attract light
objects and lodestone (a naturally magnetic iron ore) widely distributed in the Aegean
islands and adjacent lands;, and this was the first observation of electricity and
- Thales in 600 b.c. described the static electrical
phenomenon and Democritus in 450 b.c. by his atomic theory believed that matter is
consisted of atoms.
- William Gilbert, physician to Elizabeth I of
England, by his famous work, De
Magnete published in 1600, put the
scientific foundation for subsequent investigations of electricity and magnetism. As late
as 1747, electricity was defined as «that property of bodies by which when they are
heated by attrition they attract and repel light bodies at sensible distances».
- The next important advance in the knowledge of
electricity was the work of Jean Abbe Nollet in 1747. His source, the «electrical egg», so called because of its shape, contained the essentials for production
of x-rays -a vacuum tube and an outside source of high tension electricity. A little
higher vacuum and another wire sealed in the opposite end of the electrical egg could have
led to the production of x-rays. However, even if x-rays had been produced at that time,
no one would have known. The x-ray was invisible to the eye. The photographic plate,
serving as artificial retina, did not envolve until 90 years later. Also lacking was the
fluoroscent screen, which could transform the invisible short x-rays in longer waves that
the eye could perceive.
- The link between electricity and magnetism
firstly was notified by Hans Cristian Oersted and was mathematically explained by Andre
Marie Ampere in the decade 1920-30
- X-rays discovery also required a series of
mechanical and technical advances permitting the production of a strong vacuum in glass
- It was late afternoon, on Friday, November
8, 1895 that x-rays were discovered and Radiology was born. After that and more extensive
experimentation Wilhelm Conrad Roentgen was convinced that he was dealing with an entirely
«new kind of rays».
- On December 10, 1901 Roentgen received his
prize from the hands of the Swedish Crown prince in a Nobel Ceremony in the Great Hall of
the Academy of Music, Stockholm.
- On March 1st, 1896, Becquerel amazed to find that
photographic plates had been subjected to intense radiation produced by Uranium salts.
Becquerel discovered that these penetrating and invisible rays were emitted spontaneously
and persistently. This radiation had some characteristics similar to those of x-rays but
unlike x-rays it was a specific property of the atom itself. Becquerel presented his
discovery at French Academy of Sciences.
- In 1898 Marie Slodovska Curie and her husband
Pierre discovered Polonium and Radium and called the new form of energy, that was emitted,
as Radioactivity. In 1990 Curies and Becquerel began to study the
physiological effects of Radium rays.
- Pierre intentionally placed a radium sample on his
arm for 10 hours, producing a skin reaction similar to sunburn that took several months to
heal. Becquerel suffered a radiation burn after carrying the radium sample borrowed by
Curies in his vest pocket. The reddened that appeared on his abdomen soon became necrotic,
- In 1903, the Curies and Becquerel shared the Nobel
- In 1911, Marie Curie obtained the chemistry Prize
alone, the only person that ever be awarded two Nobel Prizes.
- The outbreak of World War I found Marie Curie
organizing the Radium Institute, but she immediately offered her services to develop
France medical x-ray facilities and she equipped the first radiological mobile unit
containing radiographic apparatus with dynamo to supply electricity.
- In 1934 Marie Curie fell victim to the ravages of
the element she had discovered. Constant direct handling of radium produced severe burns
on her hands, and she died on July 4, 1934 of aplastic anaemia.
- Radiography was initially considered a new
specialty in the field of photography. Most of the workers who were actively engaged in
making radiographs were photographers or physicians who practiced photography as a
hobby. Since they had no method of measuring with any precision the dosages that
they and their patients received, X-ray workers tended to rely on particular devices to
prevent burns rather than an overall program of radiation protection.
- In 1905 the chiroscope, the first quality
assurance test object served for assessing hardness of the x-ray beam, made to replace the
dangerous practice of estimating the beam by placing one’s own hand between the tube and
fluoroscopic screen. Radiation Protection devices in 1910 -protective coverings for the
operator- became so extreme that, he was «encased from top to foot in a veritable suit of armour!» (from x-ray equipment catalogue of Newton Co., London).
Generalized Radiation Protection Measures, were adopted later.
- A British x-rays and Radiation Protection
Committee formed in 1921, and an International Protection Committee in 1928.
- Greek National Atomic Energy Commission in its
first brochure in 1960 for Radiation Protection try in a simple way to explain the
possible biological action of Radiation.
- By the knowledge of x-rays and Radioactivity we
passed from Newtonian Physics to the new era of modern Physics. In the first thirty years
of twentieth Century, that Shook Physics and integrate Medicine, many scientists fed us
with their knowledge and wisdom. (Few of them: Madame Slodowska Curie, Prof Einstein, Lord
- In 18th century early attempts were made to show
relationship among elements by symbols. The Periodic Table, though, came in 1868 by
Medeleyev in Russia, a classification of the chemical elements in order of their atomic
- In 1934, Irene Joliot-Curie, daughter of Marie
Curie discovered, the way to produce artificial Radioactivity for which they were awarded
the 1935 Nobel Prize for Chemistry.
- After that, Emilio Segre found the missing element
43, the first artificially produced element. It was named technetium from the Greek word
- Radium tragedies were not repeated with isotopes.
In the 60 years since artificially produced radioisotopes were firstly used in humans, we
have not run into delayed effects or complications. The very first published
observation that some radioactive elements accumulate in human tissues and cause
pathologic changes was made by Blum in 1925.
- In 1935, Hevesy was the first to use an
artificially produced nuclide in the study of animal metabolism. The Geiger-Muller
Counter -perfected in 1928- offered non invasive means of detecting and measuring the
uptake of various radionuclides under physiological conditions and until 1949, G.M. tube
was the only external counting device available for the detection of radionuclides such as
radioactive Iodine. Three years after Fermi had produced, in 1938, radioactive
Iodine, by means of neutron bombardment of stable Iodine, a colloquium was held on the
subject "What Physics can do
for Biology and Medicine"
- and this led to the use of radioactive Iodine in
Medicine. The first report on the administration of radioactive iodine to the human
thyroid gland was from Berkeley.
- In 1942 a group from Columbia reported the first
case of metastatic thyroid carcinoma to be shown by G-M Counter and autoradiography.
- First rectilinear Scanner was made in 1951 by
Cassen and whole body Scanner was, firstly, described to the Society of Nuclear Medicine
in 1966. With it one could image the distribution of ã-emitters in the entire human body.
- «Scintillation Camera» was
the title appeared on Anger’s paper published in January 1958 and the usefulness of this
first scintillation camera was illustrated by 4 in vivo images of human thyroid glands.
Anger's instrument was conceived, constructed and demonstrated only 10 year after Kallman
discovered the scintillation detector in 1947. Historically, no single discovery and
invention made during the last 5 decades has been so pivotal to the emergence of Nuclear
Medicine as a discipline.
- As late as 1900 ultrasound was still a novelty. By
1930 it had become an interesting but small area of Physics research. In the 1960 and
1970’s, however, it became an important research tool in Physics and a rival to the
X-ray in medicine. The application in medical imaging for diagnosis and evaluation
of internal organs by the Piezoelectricity phenomenon (an AC voltage across the opposite
faces of a plate produces vibrations of this at the impressed frequency), was first
discovered in the 1880’s by Paul-Jacque and Irene Curie.
- The first attempts to use ultrasound for
diagnostic purposes were made as early as 1937. In that year Dussik brothers began to
study the possibility of making images of the brain by transmitted ultrasound and in 1942,
they published their first «hyperphonogram». Howry started work in his basement in
Denver late in 1947 and by 1949 was displaying echoes from soft tissue interfaces.
In 1952 Howry published 2 dimensional ultrasonic tomogram. His early scanning system used
water-bath immersion. Howry’s scanning tank was the gun turret of a bomber aeroplane.
One of the most famous of his scans was that of the neck. He called his device a somascope
after the Greek word soma that means body.
- By 1960 articulated arm contact scanner
developed under the direction of Joseph Holmes. Green of Stanford Research Institute made
ultrasonic transmission images and presented an example of the thoracic cavity of a
newborn infant where one could notice the details of the bony skeleton and their
similarity to the image obtained with conventional X-ray techniques.
- On December 16th, 1953, Leksell made the
first measurement of a midline shift that was of diagnostic importance on a 16 months old
boy; within 2 hours Leksell operated upon the child. Following the publication of
Leksell’s more midline echoencephalography was adopted with enthusiasm.
- In 1842 Doppler effect (if a wave source is moving
in relation to an observer the perceived wave frequency is different from the emitted
frequency ) was predicted by Doppler on theoretical grounds and on 3 June 1845, Buys
Ballot tested Doppler’s theory experimentally.
- Computers in Nuclear Medicine
- Experiments on atomic and nuclear structure
during the first half of this century led quite naturally to the subsequent development of
the novel areas of Nuclear Medicine and digital computation. By the mid-60s the
major area of computer utilization involved the statistical analysis of data obtained
using scintillation detectors, but in the late 1960s the major application of them had
shifted to the manipulation (store & process)of data from dynamic studies.
- Present day computer use in Nuclear Medicine
involves two basic
" Dynamic studies, Image Quality ".
- In Nuclear Medicine, the need for image
discrimination in the third dimension has always been a challenge. Radiologists developed
the word tomography from the Greek words «tome» meaning to cut and «graphy» meaning to
write. In 1970, Freedman proposed and built a rotating tomographic ã-camera.
- An entirely, different concept associated with
positron emission was exploited by Robertson & Brownell who built the PET
camera. Today systems can give sophisticated tomograms and 3D images, as heart image
by Tl201, while new radiopharmaceuticals as monoclonal antibodies can give specific images
of the lesion.
- In 1984, Koehler and Milstein won the Nobel Prize
for inventing a technique to produce large quantities of mouse monoclonal antibodies with
tumor specific antibodies. One can imagine a true «magic bullet» a material that will go
directly to the tumor for not only imaging but also for therapeutic purposes - with the
appropriate radioactive label.
- The past 100 years have been witness to an
enormous development of imaging technology as X-ray tubes, Computerized Tomography[CT],
Single Photon Emission Tomography [SPECT] and Positron Emission Tomography [PET] imaging
techniques or non-ionizing radiation modalities such as Magnetic Resonance Imaging [MRI]
and Ultrasound. So the future of the Medical examination by Radiation in the next century
Maria Lyra Georgosopoulou
Assoc. Prof. Medical Physicist
University of Athens
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