Wilhelm Conrad Roentgen. The discovery of x-rays and the creation of a new medical profession

Roentgen with his parents

Wilhelm Conrad Röntgen (Lennep, March 27, 1845-Munich, February 10, 1923).

The son of Friedrich Conrad (1801-1884) and Charlotte Constanze (1806-1888), he was born in the German town of Lennep on March 27, 1845. When the revolution spread through Germany, the family moved to the Netherlands in 1848. It was in Apeldoorn that Wilhelm lived most of his childhood.

In 1862 he enrolled in the Technical School of Utrecht, going to live in the house of Dr. Jan Willem Gunning, a friend of his father, who was the one who awakened in the young Wilhelm his fascination with natural sciences. However, Roentgen did not finish his secondary studies (necessary to enter the university) since he was expelled from it in 1863 when he was accused of drawing a caricature of a professor (an act supposedly carried out by a classmate).

While auditing the University of Utrecht, Roentgen learned that the Polytechnikum in Zurich admitted students through an entrance exam without requiring a high school completion certificate. Thanks to this he was able to study Mechanical Engineering (Switzerland, 1865-1869). However, once he obtained his bachelor's degree, he changed his subject for postgraduate studies and received a doctorate in Physics in 1869. The influence of August Kundt (1839-1894) was decisive, so much so that Roentgen would always remember him as the person who had introduced him in physics and had dispelled all his doubts about his future.

The second great love of his life

Roentgen and his wife Anna Bertha

In Zurich he met Anna Bertha Ludwing (1839-1919), daughter of a tavern owner. The couple married in Apeldoorn on January 19, 1872 after obtaining the approval of his parents. Bertha's parents were not invited to the wedding as they were from a lower social stratum than the Roentgen family. Their marriage lasted 47 years, until Bertha passed away in 1919 after suffering from various chronic illnesses.

In Kundt's laboratory

The beginning of Roentgen's career took place in Kundt's laboratory. In 1870, when he finished his doctoral thesis, he followed his mentor to Würzburg where they set up a new laboratory. However, two years later they moved to Strasburg, where the German Empire had founded an elite national university, which offered Kundt a position.

In 1875, Wilhelm went to Hohenheim to take up a professorship, since he was able to obtain the “habilitation” (a higher education degree in Germany that allows one to accept a university professorship) and his teaching certificate. However, disillusioned in his position as professor of Mathematics and Physics, he returned to Strasbourg a year later. Finally, in 1879, he obtained his first appointment as full professor at Ludwig's University in Giessen.

The lone investigator

Roentgen had his own research institute during his time as a professor in Giessen (1879-1888). In a short time he earned a reputation as an excellent researcher and a demanding teacher, but at that time experimental physics was only a secondary science and few students attended laboratory practices.

At this stage of his life he made certain significant discoveries such as dielectric convection, which was a fundamental piece for the theory of electromagnetism that was emerging at that time.

In 1888 he was summoned from Würzburg. The change was received as favorable since he had a greater number of students (and therefore higher fees) and also the building was suitable for his work as a researcher due to the absence of vibrations.

Roentgen was a peculiar physicist who did not like long lectures or scientific conventions. In fact, at that time, his publications hardly had a wide acceptance and his colleagues came to accuse him of not having creativity.

The revelation of one night: the discovery of lightning

“I had not revealed anything to anyone about my work. I told my wife that I was doing something that she would make people, when she found out about it, say: `Roentgen has lost his mind,'” Wilhelm told Ludwig Zehnder on January 15, 1896.

Anna Bertha hand

There are many unknowns regarding what happened the night of the discovery, among other things, because Roentgen had part of his belongings burned after his death. Probably while experimenting with cathode rays, Wilhelm accidentally saw the mysterious luminescence of wallpaper with a light-sensitive fluorescent substance (barium platinocyanide). He knew that he had stumbled upon something totally new and spent the next few days and nights investigating the properties of those rays. He noted that the rays could penetrate almost anything, including his wife's hand, but not bone (which left a shadow on a photosensitive plate). The results of his research were published in the article “On a new class of lightning”.

Roentgen's popularity survived overnight, awards, honors and orders rained down on him. This fact made his work in the laboratory difficult, so he ended up isolating himself not only from the public but also from his colleagues.

Roentgen reached the zenith of his career with the offer of the Ludwig Maximilian University of Munich in 1900 and with the recognition of the Nobel Prize in 1901. However, the argument about who really discovered X-rays haunted him for the rest of his life since many researchers claimed their authorship alleging that these rays had always existed and that Roentgen was simply the one who perceived them for the first time.

Loneliness and death

Roentgen tomb in Giessen

In 1915, the biologist Theodor Boveri, a good friend of Roentgen, died and in 1919 his wife died. It was in those years that he retired from teaching and dedicated himself to thinking about his last will and testament. Thus, he stipulated that his notes and documents were to be kept after his death and both his scientific publications and the Nobel Prize medal were to be bequeathed to the University of Würzburg. Roentgen died in 1923, in Munich, at the age of 78.

One profession, different scientific cultures

From the first year of the discovery of X-rays, medical specialists began to use them by purchasing the equipment with their own resources and converting hospital basements into radiology rooms.

First radiological examination, 1896

The first department of the specialty was created in Glasgow in 1896. The devices used at that time were very simple. The X-ray tubes were mounted on a stand while the patients sat in chairs holding the photo plates against their own bodies. It was after the First World War that technology gained a faster pace and radiology gained a place within science. Thus, we are witnessing the creation of a new independent professional specialty. At first, the radiologist fulfilled various functions: doctor, assistant, photographer, mechanic, file clerk and record keeper, to later create different figures with different specializations.

The First World War marked a milestone in the first phase of radiological experimentation since millions of wounded and maimed soldiers contributed to extending the use of X-rays. In this way, the social importance of the young profession was demonstrated and its technology being favored in the civilian world due to the spread of health insurance that covered the costs of X-rays.

First successes of a new discipline

First chest X-ray, 1896

During the first year after the discovery, a total of 49 books and documents and 1044 essays on scientific aspects and possible applications of lightning were written.

In principle, the application of X-rays was limited to the description of the bone structure of the extremities, moving on to the detection of numerous anatomical alterations and bone diseases of great importance for surgical management.

First dental X-rays

Scotsman John Macintyre (1857-1923) was the one who performed the first in situ chest X-ray. With an exposure time of 60 minutes and quite blurred radiographs, the diagnosis was based on details such as the shape and size of the heart, the position of the diaphragm, the shadows caused by the pleural fluid or the translucency of the pneumothorax.

Regarding the use of contrasts, the first attempts were made by Eduard Haschek and Otto Lindenthal in Vienna. They used a mixture of lime, mercury, and petroleum to take an X-ray of the blood vessels in a severed hand.

In July 1896 urologist John Macintyre managed to take an X-ray of a kidney stone. In the gynecological area, the American obstetrician Edward Parker Davis achieved the first plate by placing the skull of a fetus inside the pelvis of a female cadaver with an exposure time of one and a half hours. Otto Walkhoff and Friedrich Giesel made the first dental radiography in Braunschweig, Germany. For his part, the dermatologist Leopold Freund was the first to perform radiotherapy, in Vienna. The patient was a girl with a large mole on her neck and back. However, after 10 days receiving daily radiation, she developed skin lesions and she developed central necrosis.

Radiology today

Progress in this area has been the result of a fruitful interaction between basic sciences, clinical medicine and manufacturers. We have interventional radiology, ultrasounds, CT scans, MRIs and positron emission resonances. The traditional contrast medium has been replaced by modern agents and digital imaging radiographic film.

First computed tomography, 1972

The introduction of positron emission tomography and molecular imaging techniques have generated great advances, which will play a great role in the future when evaluating the functional and pathological alterations observed in tissues.

The way radiologists work has also changed in recent years. Greater clinical commitment and a multidisciplinary approach are producing better results and better patient care. Radiologists are currently playing a central role in the management and treatment of certain diseases.

Source: U. Busch

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