What is radiology?

X-rays, CT scans, ultrasounds, MRI scans, these are all kinds of methods with which the radiologist makes diagnoses. Radiology is concerned with determining the nature and location of conditions, injuries and diseases. This involves using X-rays and other examinations. What exactly does radiology entail?

What is radiology?

Radiology, which comes from the Greek words “radio” (rays) and “logos” (science), concerns the evaluation of X-rays. When there are abnormalities or diseases in the body that cannot be seen externally (from the outside), the radiologist is often called in. Disorders of the body are diagnosed using scans using radiation, sound waves and magnetic fields.


The most commonly used rays are X-rays and X-rays. This includes CT scans and X-rays. These were the most commonly used until recently. Nowadays, however, the following two techniques are used more: waves and fields.

X-rays were discovered by Wilhelm Röntgen and they are electromagnetic radiation, a radiation between ultraviolet and gamma rays. The radiation is somewhat harmful, but this outweighs its usefulness. Imaging occurs because the radiation is transmitted through soft tissues and blocked by harder tissue. So the radiation passes through cartilage and not through the bone, making the bone visible. It is used for photos, the CT scan and fluoroscopy.

For example, with a CT scan, a person goes through a machine with the X-ray source on one side and the detector on the other. As the radiation passes through the body, all tissues are weakened. The strength of the remaining radiation is measured. Multiple measurements are then taken to create a 2-dimensional image.

Sound waves

A more commonly used technique today is ultrasound. This is mainly used in pregnant women to look at the fetus. Ultrasound is also called ultrasonography. A reflection of interfaces between hard and soft structures is shown. These are ultrasonic sounds, inaudible to humans. Speed, direction and intensity can be determined with the equipment.

Ultrasound shows especially well the organs consisting of soft tissue. This is therefore very suitable for weeks of injury (for example muscles).

Magnetic fields

NMR, MR or MRI are forms of magnetic field scans. NMR stands for Nuclear Magnetic Resonance and is used in chemistry and medicine. The newer name MRI is particularly well known. MRI stands for Magnetic Resonance Imaging in which people are placed in a scanner. This is a movable table with which someone then passes through the scanner containing a magnetic field. Not everyone can simply be placed in a scanner because some metal objects pose a danger. If someone carries endoprostheses, pacemakers, IUDs, neurostimulators, insulin pumps, intraocular metal particles, metal artificial heart valves and cochlear implants, an MRI scan is not recommended. The objects can be attracted by the magnetic field.

The difference with a CT scan is that it measures the absorption of X-rays and with MRI there is no exposure to radiation.


The radiologist specializes in assessing X-rays for diseases or abnormalities of the body. A radiologist has studied medicine for six years and then specialized in medical imaging for five years. Activities of the radiologist include:

  • Treating patients without surgery (with ultrasound), such as applying angioplasty (angioplasty) to widen narrowed arteries, as well as removing inflammation
  • Taking photos, scans and the like for diagnosis

The diagnosis and advice of a radiologist are usually decisive.