UNIT 21: Medical Physics Applications
Radiation use in medical diagnosis and treatment.
Aim A: Explore the principles, production, uses and benefits of non- ionising instrumentation techniques in
medical applications.
Aim B: Explore the principles, production, uses and benefits of ionising instrumentation techniques in medical
applications
Introduction:
In order to support my application to study Diagnostic Radiography and Imaging at university, I have secured a
placement within the Radiography Department of a teaching hospital. This clinical placement will allow me to
shadow the work of a qualified Radiographer and gain valuable experience in the uses of ionising and
non-ionising radiation in the diagnosis and treatment of a variety of medical conditions. Non-ionising radiation
technologies are widely used for imaging, therapy, and treatment in medical applications. Unlike ionising
radiation (such as X-rays and gamma rays), non-ionising radiation does not have enough energy to remove
tightly bound electrons from atoms, making it generally safer for both patients and healthcare professionals.
Techniques such as MRI, ultrasound, and infrared thermography are essential in modern medicine for their
non-invasive nature and diagnostic effectiveness. MRI uses magnetic fields and radio waves to produce detailed
images of soft tissues; ultrasound employs high-frequency sound waves for real-time imaging, especially in
prenatal care and cardiac assessments; and infrared thermography helps detect heat-related changes on the
body’s surface. While these technologies pose minimal risk, proper training and safety protocols are still essential
to ensure accurate and safe use. At the end of my placement, I will create a presentation to showcase my
knowledge and understanding of these technologies, which I will use during my university interviews to
demonstrate my readiness and enthusiasm for a career in diagnostic radiography.
A. P1 Explain how the principles and production of non-ionising radiation technologies are used in
medical applications.
What is radiation?
Radiation is energy that travels from one place to another through
particles or waves. It can help you but equally harm you. We are
exposed to it every day. Radiation is used in many applications, such
as cancer treatment, energy production, and medical imaging, such
as X-rays.
, What is non-ionising radiation?
Non-ionising radiation that has a low power energy level that doesn't have
enough energy to remove an electron from a molecule or an atom. Which is
also a type of electromagnetic radiation. Non-ionising is almost safe
without much damage For example:
● Radio waves- it has the longest wavelength in the electromagnetic
spectrum
● Microwaves- it has a wavelength shorter
than radio waves but longer than infrared waves
● Infrared radiation- it has a wavelength longer than that of visible light but
shorter than microwaves
● Visible light- is a band of the electromagnetic spectrum that is visible to the
human eye
● Ultraviolet radiation-it is shorter than that of visible light but longer than
X-rays
How is non-ionising radiation used in medical diagnosis?
Non-ionising radiation is used in a range of medical imaging techniques that allow healthcare professionals to
safely examine the inside of the body without exposing patients to the risks associated with ionising radiation.
Methods such as ultrasound, MRI (Magnetic Resonance Imaging), and infrared thermography rely on sound
waves, magnetic fields, or heat detection to produce detailed images of tissues and organs. These techniques are
commonly used to diagnose conditions affecting soft tissues, muscles, joints, the brain, and unborn babies
during pregnancy. Because non-ionising radiation does not damage cells or DNA, it provides a safer alternative
for repeated use, especially in vulnerable patients like children or pregnant women.
A. P2 Explain why non-ionising radiation technologies are used for diagnosis and treatment of the
human body
Why is non-ionising radiation used in medical diagnosis?
Non-ionising radiation is used in medical diagnosis because it is much safer than ionising radiation. It does not
carry enough energy to damage cells or DNA, making it a preferred choice for imaging, especially in sensitive
groups like pregnant women and children. It is ideal for examining soft tissues, such as in MRI and ultrasound
scans, and can be safely used multiple times without harmful side effects. This makes it highly suitable for
ongoing monitoring, routine check-ups, and early detection of health conditions.
How does it work Uses Aspects of non Risks
ionising radiation
MRI It uses a very strong ● Brain Magnetic field and Strong magnetic field
, magnetic field and scanning radiofrequency can attract or repel
radiofrequency, which ● Soft tissue energy metal objects. This is
creates clear images of the damage MRI does not use dangerous for
internal structure of your ● Diagnosing ionising radiation patients with metal
body like muscles, organs, cancer and implants for example,
and soft tissues. It's also tumors pacemakers, dental
important that patients ● Muscle and implants, joint or hip
take anything magnetic off joint injuries replacement.
of them because it's going Patients with
to get caught in the claustrophobia or
machine and also that the anxiety may have a
tools that the doctors are panic attack or feel
using are also not discomfort due to
magnetic. This is because the limited space
once you turn off the inside the machine.
machine, you can never The MRI machine is
turn it back on. very loud because the
metal coils vibrate,
which creates loud
sounds and being
exposed to sentence
noise can lead to
hearing damage,
which can be
prevented by wearing
something to protect
your ears
Ultrasound It uses high-frequency ● Used during Sound waves which Ultrasound is
sound waves to create pregnancy to are non-ionising considered safe,
images inside your body. see the radiation which is especially compared
The sound waves bounce health of the used to capture to imaging that uses
off tissue and return to the baby pictures ionising radiation.
device, creating echoes that ● Checking However, slight
create images. the thyroid tissue heating or tiny
gland gas bubbles
● Guiding a (cavitation) may
needle occur with
● Diagnosing prolonged or
gallbladder high-intensity use.
disease These risks are rare,
and ultrasound
should be used only
when medically
Radiation use in medical diagnosis and treatment.
Aim A: Explore the principles, production, uses and benefits of non- ionising instrumentation techniques in
medical applications.
Aim B: Explore the principles, production, uses and benefits of ionising instrumentation techniques in medical
applications
Introduction:
In order to support my application to study Diagnostic Radiography and Imaging at university, I have secured a
placement within the Radiography Department of a teaching hospital. This clinical placement will allow me to
shadow the work of a qualified Radiographer and gain valuable experience in the uses of ionising and
non-ionising radiation in the diagnosis and treatment of a variety of medical conditions. Non-ionising radiation
technologies are widely used for imaging, therapy, and treatment in medical applications. Unlike ionising
radiation (such as X-rays and gamma rays), non-ionising radiation does not have enough energy to remove
tightly bound electrons from atoms, making it generally safer for both patients and healthcare professionals.
Techniques such as MRI, ultrasound, and infrared thermography are essential in modern medicine for their
non-invasive nature and diagnostic effectiveness. MRI uses magnetic fields and radio waves to produce detailed
images of soft tissues; ultrasound employs high-frequency sound waves for real-time imaging, especially in
prenatal care and cardiac assessments; and infrared thermography helps detect heat-related changes on the
body’s surface. While these technologies pose minimal risk, proper training and safety protocols are still essential
to ensure accurate and safe use. At the end of my placement, I will create a presentation to showcase my
knowledge and understanding of these technologies, which I will use during my university interviews to
demonstrate my readiness and enthusiasm for a career in diagnostic radiography.
A. P1 Explain how the principles and production of non-ionising radiation technologies are used in
medical applications.
What is radiation?
Radiation is energy that travels from one place to another through
particles or waves. It can help you but equally harm you. We are
exposed to it every day. Radiation is used in many applications, such
as cancer treatment, energy production, and medical imaging, such
as X-rays.
, What is non-ionising radiation?
Non-ionising radiation that has a low power energy level that doesn't have
enough energy to remove an electron from a molecule or an atom. Which is
also a type of electromagnetic radiation. Non-ionising is almost safe
without much damage For example:
● Radio waves- it has the longest wavelength in the electromagnetic
spectrum
● Microwaves- it has a wavelength shorter
than radio waves but longer than infrared waves
● Infrared radiation- it has a wavelength longer than that of visible light but
shorter than microwaves
● Visible light- is a band of the electromagnetic spectrum that is visible to the
human eye
● Ultraviolet radiation-it is shorter than that of visible light but longer than
X-rays
How is non-ionising radiation used in medical diagnosis?
Non-ionising radiation is used in a range of medical imaging techniques that allow healthcare professionals to
safely examine the inside of the body without exposing patients to the risks associated with ionising radiation.
Methods such as ultrasound, MRI (Magnetic Resonance Imaging), and infrared thermography rely on sound
waves, magnetic fields, or heat detection to produce detailed images of tissues and organs. These techniques are
commonly used to diagnose conditions affecting soft tissues, muscles, joints, the brain, and unborn babies
during pregnancy. Because non-ionising radiation does not damage cells or DNA, it provides a safer alternative
for repeated use, especially in vulnerable patients like children or pregnant women.
A. P2 Explain why non-ionising radiation technologies are used for diagnosis and treatment of the
human body
Why is non-ionising radiation used in medical diagnosis?
Non-ionising radiation is used in medical diagnosis because it is much safer than ionising radiation. It does not
carry enough energy to damage cells or DNA, making it a preferred choice for imaging, especially in sensitive
groups like pregnant women and children. It is ideal for examining soft tissues, such as in MRI and ultrasound
scans, and can be safely used multiple times without harmful side effects. This makes it highly suitable for
ongoing monitoring, routine check-ups, and early detection of health conditions.
How does it work Uses Aspects of non Risks
ionising radiation
MRI It uses a very strong ● Brain Magnetic field and Strong magnetic field
, magnetic field and scanning radiofrequency can attract or repel
radiofrequency, which ● Soft tissue energy metal objects. This is
creates clear images of the damage MRI does not use dangerous for
internal structure of your ● Diagnosing ionising radiation patients with metal
body like muscles, organs, cancer and implants for example,
and soft tissues. It's also tumors pacemakers, dental
important that patients ● Muscle and implants, joint or hip
take anything magnetic off joint injuries replacement.
of them because it's going Patients with
to get caught in the claustrophobia or
machine and also that the anxiety may have a
tools that the doctors are panic attack or feel
using are also not discomfort due to
magnetic. This is because the limited space
once you turn off the inside the machine.
machine, you can never The MRI machine is
turn it back on. very loud because the
metal coils vibrate,
which creates loud
sounds and being
exposed to sentence
noise can lead to
hearing damage,
which can be
prevented by wearing
something to protect
your ears
Ultrasound It uses high-frequency ● Used during Sound waves which Ultrasound is
sound waves to create pregnancy to are non-ionising considered safe,
images inside your body. see the radiation which is especially compared
The sound waves bounce health of the used to capture to imaging that uses
off tissue and return to the baby pictures ionising radiation.
device, creating echoes that ● Checking However, slight
create images. the thyroid tissue heating or tiny
gland gas bubbles
● Guiding a (cavitation) may
needle occur with
● Diagnosing prolonged or
gallbladder high-intensity use.
disease These risks are rare,
and ultrasound
should be used only
when medically
