21C can be found on page 15
AB
Introduction:
To support my application to study Diagnostic Radiography and Imaging at
university, I have secured a clinical placement within the Radiography Department of
a teaching hospital. During this placement, I will have the opportunity to shadow a
qualified Radiographer and gain hands-on insight into the day-to-day responsibilities
of the role. This experience will allow me to observe how both ionising and
non-ionising radiation techniques are used to diagnose and monitor a wide range of
medical conditions. I aim to develop a deeper understanding of imaging procedures
such as X-rays, CT scans, MRI, and ultrasound, as well as the importance of patient
care, safety protocols, and effective communication. On completion of my
placement, I will produce a presentation that demonstrates my knowledge and
reflections, which I will use to support my university interviews and showcase my
readiness for the course.
Ionising radiation techniques
X-rays
The first Ionising radiation technique I will be discussing are x-rays , they are quick
and highly effective in diagnosing conditions involving bones , lungs and some soft
tissues. X-rays use ionising radiation to make images , it can do this as the radiation
passes through the body and is absorbed at different rates by different tissues. An
example where a x-ray would be used to check for a broken bone , the x-ray will
clearly show bone density and lung structure allowing them to make accurate
decisions. They use ionising radiation to create detailed images by passing through
the body and being absorbed at different rates by different tissues. Theres nothing
healing about x-rays , they're diagnostic only however they can help check the
healing process. There is a small risk of radiation exposure that patients must be
informed of , this is important especially for children and pregnant women.
,What do X-rays consist of ?
X-rays are a form of electromagnetic radiation, similar to visible light but with
much shorter wavelengths and higher energy. They normally have wavelengths
ranging from 0.01 to 10 nanometres and frequencies between 30 petahertz and 30
exahertz. X-rays are between ultraviolet light and gamma rays on the
electromagnetic spectrum.
They have photons, which are packets of energy that travel in waves. As they have
alot of energy they penetrate soft tissues in the body, while being absorbed by
denser materials like bones or metal. The contrast in an X-ray picture is produced by
this differential absorption. In X-ray tubes, high-speed electrons crash with a metal
target, such tungsten, causing the electrons to abruptly slow down and emit X-ray
photons, a process known as Bremsstrahlung radiation. This creates X-rays
artificially. X-rays' usage in medical imaging must be properly regulated and justified
due to their ionising properties, which can harm live cells by upsetting DNA and
atomic structures.
How are X-rays produced?
X-rays are produced when high-speed electrons decelerate rapidly and their kinetic
energy is converted into photons. This process typically occurs in an X-ray tube,
where electrons are accelerated towards a metal target. When the high-speed
, electrons collide with the metal atoms, they rapidly decelerate, and this sudden loss
of kinetic energy is converted into electromagnetic radiation (X-rays) through a
process known as "braking radiation" . When entering electrons knock off inner-shell
electrons from metal atoms, electrons from higher energy levels fall into the lower
shells and emit X-ray photons with certain energies, producing characteristic
radiation. The tube is surrounded by a lead case to screen it from harmful radiation,
and a vacuum inside the tube keeps air particles from interfering. After that, the
generated X-rays are aimed towards the patient for imaging through a window.
Principles
The main principle behind X-rays is differential absorption, where different densities
in the body absorb X-ray photons to different extents, creating contrast on an image.
When X-rays pass through the body, denser structures absorb more radiation,
appearing white or light on an X-ray film or detector, while softer tissues like muscles
or fat absorb less, appearing in shades of grey. Air absorbs the least so it looks
black. This enables medical professionals to see anomalies and differentiate
between structures. The atomic number, density, and thickness of the substance that
the X-rays travel through all affect how much energy is absorbed. Additionally, by
momentarily raising their density, contrast chemicals can improve the visibility of
certain organs or blood arteries. In order to maximise picture quality and minimise
radiation dosage, X-ray imaging depends on exact exposure settings that adhere to
the ALARA principle (As Low As Reasonably Achievable) to safeguard patient
safety.
Diagnostic uses
X-rays are used alot in the medical field to look at internal structures of the body , it
helps with the spotting of different medical situations. Since bones easily absorb
X-rays and show up clearly on the picture, their main application is in imaging bones
to find fractures, dislocations, and bone infections. By identifying anomalies in lung
tissue and fluid buildup, X-rays are utilised in chest radiography to diagnose lung
diseases such pneumonia, TB, collapsed lungs, and lung cancer. Dental X-rays are
frequently used to find impacted teeth, abscesses, and tooth rot. They are also
essential for directing orthopaedic treatments and detecting foreign items within the
body. X-rays are used in conjunction with contrast media in procedures such as
angiography to investigate problems in the digestive tract and inspect blood vessels.
Healthcare providers may use these diagnostic tools to identify illnesses early, track
their development, and decide on the best course of action.
Benefits
X-rays offer many benefits , they are non-invasive and quick for examining
inside structures of the body. They are perfect for urgent diagnostic requirements