Chapter 3

There have been a number of discoveries over the past several decades that have changed the course of modern medicine. It is difficult to imagine, for instance, the practice of medicine without the use of antibiotics for infection and chemotherapeutic agents for neoplasms. The world in which medicine was practiced less than two generations ago, however, included neither of these types of agents. Other discoveries, often made serendipitously, have also significantly changed the way in which medicine is practiced. The discovery of the x-ray by Wilhelm Röntgen in 1895 is one such example.

Röntgen noticed a fluorescent glow arising from some barium-covered photographic plates while working on a Crooke’s tube in his laboratory. Because the plates could obtain the phosphorescent glow only by being exposed to radiation and because no form of radiation known at the time had the ability to penetrate the black paper covering the plates, Röntgen proposed a mysterious new form of radiation that he called “x-rays.” A few weeks later Röntgen presented his discovery at a physics conference and shortly thereafter in printed form as a brief 10-page paper. The first reports of the clinical utility of the new rays were published within the year; Röntgen had opened the way for a new field of medicine subsequently known as radiology. He was awarded the first Nobel Prize in physics for his discovery.

The clinical practice of radiology initially consisted solely of images obtained with a combination of x-rays and photographic film. The field now includes such diverse modalities as x-rays, nuclear medicine studies, angiography, computed tomography (CT), ultrasound (US), and magnetic resonance imaging (MRI). In addition, the realm of radiology has extended beyond the diagnostic arena into therapy; radiation therapy and interventional radiology are specialties within the field of radiology that are primarily concerned with treatment of patients.

The form of ionizing radiation that produces x-rays can, however, be detrimental. Case reports of radiation burns suffered as a result of working with x-rays appeared a few months following Röntgen’s discovery; in 1896, 23 cases of radiodermatitis were reported. The Curie family, frequently credited with discovering natural radiation sources in the form of radium, suffered severely from radiation-induced disease. Marie Curie and her daughter Irene both died from leukemia, and Pierre had leukemia when he was killed in a carriage accident. It took many years for radiation safety to become standard in the field of radiology and many patients as well as practitioners suffered ill effects from what were once considered harmless rays.

Several modifications in the x-ray tube have made modern imaging modalities significantly safer than those around the start of the twentieth century. Proper shielding used on both x-ray tubes and patients significantly decreases exposure of patients and surrounding personnel. In addition, more homogeneous x-ray beams, leading to a decrease in the amount of harmful low-energy x-rays, has significantly decreased the risk to patients. Other developments, such as proper ...

Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.

Ok

## Subscription Options

### AccessMedicine Full Site: One-Year Subscription

Connect to the full suite of AccessMedicine content and resources including more than 250 examination and procedural videos, patient safety modules, an extensive drug database, Q&A, Case Files, and more.