UNIT 21: Medical Physics Applications
Health and Safety in the medical use of ionising and non-ionising radiation
technologies.
Aim C: Understand health and safety, associated risks, side effects and limitations of ionising and non-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. During this clinical placement, I will have
the opportunity to shadow the work of a qualified Radiographer and gain valuable hands-on experience in the
safe use of both ionising and non-ionising radiation technologies. Medical imaging techniques such as X-rays,
MRI, and ultrasound play a vital role in diagnosing, monitoring, and treating a wide range of health conditions.
These techniques rely on different forms of radiation, each with its own set of applications, risks, side effects,
and limitations. Ionising radiation, used in procedures like X-rays and CT scans, can pose health risks if not
managed properly, requiring strict safety protocols to protect both patients and healthcare professionals.
Non-ionising techniques, such as MRI, ultrasound, and infrared imaging, are generally safer but still require
careful use to avoid issues like tissue heating or problems with metal implants. Through my placement, I aim to
deepen my understanding of how these technologies work, recognise their potential hazards, and observe the
control measures in place to ensure safe and effective imaging. At the end of my placement, I will produce a
report to demonstrate my knowledge and understanding of these essential topics in preparation for my future
studies and career.
C. P5 Explain the health and safety risks, side effects and limitations of non-ionising and ionising
radiation technologies.
Ionising radiation
Risks
Ionising radiation carries several potential risks, especially due to its ability to damage living tissues and DNA.
One of the most significant risks is the increased likelihood of developing cancer from prolonged or repeated
exposure. Medical imaging techniques such as CT scans or X-rays use low doses of radiation, but cumulative
exposure over time can still be harmful. There's also a risk to healthcare workers who are repeatedly exposed to
radiation if proper shielding and protocols are not followed.
Side effects
The side effects of ionising radiation vary depending on the dose and part of the body exposed. In therapeutic
contexts like radiotherapy, patients might experience skin burns, fatigue, nausea, or damage to healthy tissues
,near the treatment site. Long-term side effects may include scarring, organ damage, or infertility if reproductive
organs are exposed. These side effects can sometimes outweigh the benefits, especially if not carefully managed.
Limitations
Despite its effectiveness, ionising radiation in medical physics has limitations. It is not suitable for all patients,
pregnant women and children are especially vulnerable. It also cannot distinguish between cancerous and
healthy cells without precise targeting, which can lead to collateral damage. Some diseases or injuries do not
show up clearly on radiographic images, limiting diagnostic accuracy. Furthermore, the infrastructure and
training required to safely use ionising radiation are costly, limiting access in low-resource settings.
Non-ionising
Risks
Although generally safer than ionising radiation, non-ionising radiation still presents some risks. For example,
prolonged exposure to strong electromagnetic fields, such as those used in MRI (Magnetic Resonance Imaging),
can induce currents in the body, potentially causing nerve or muscle stimulation. There’s also concern about the
heating effects of radiofrequency (RF) radiation, which can increase tissue temperature, especially in
high-intensity applications. Additionally, metallic implants or pacemakers can pose serious safety issues during
MRI scans.
Side effects
Side effects from non-ionising radiation are rare but can occur. Some patients report dizziness, nausea, or a
feeling of warmth during MRI procedures due to changes in magnetic fields or noise levels. In therapies like
ultrasound, if used improperly, localised tissue heating or cavitation formation of small gas bubbles can occur,
potentially leading to tissue damage. However, these effects are generally mild and avoidable with correct usage.
Limitations
Non-ionising radiation techniques also have several limitations. MRI scans, while very detailed, are expensive,
time-consuming, and not suitable for patients with certain metal implants. Ultrasound imaging, another
non-ionising method, is less effective for imaging areas surrounded by bone or gas like the brain or lungs.
Moreover, non-ionising methods often lack the resolution or depth penetration needed for diagnosing some
internal conditions, limiting their diagnostic range compared to ionising techniques like CT scans.
Ionising radiation (X-rays, CT scans, Radiotherapy)
X-rays
● Risks
X-rays involve exposure to ionising radiation, which can pose cancer risks over time if used repeatedly.
Although individual doses are relatively low, cumulative exposure, especially in medical staff or patients
undergoing regular scans, can be harmful.
, ● Side Effects
X-rays rarely cause immediate side effects, but prolonged exposure may result in localized tissue damage
or contribute to long-term health issues. In dental or chest X-rays, for instance, the risk is extremely low,
but still present.
● Limitations
X-rays are limited in how much detail they can provide, especially for soft tissues like the brain or
internal organs. They offer two-dimensional images, which can make it difficult to detect certain
abnormalities. Overlapping structures can obscure problems, and small tumors or early-stage diseases
may not be visible.
CT scans
● Risks
CT (Computed Tomography) scans expose patients to significantly higher doses of ionising radiation
than standard X-rays. Repeated scans over time can increase the risk of developing cancer, particularly
in younger patients or those who require frequent imaging. There is also a small risk of allergic reactions
to contrast dyes used during some scans.
● Side effects
Short-term side effects from CT scans are generally minimal but can include discomfort from lying still
for long periods or reactions to contrast agents, such as nausea, rash, or dizziness. In rare cases, contrast
dye may affect kidney function, especially in patients with pre-existing kidney problems.
● Limitations
While CT scans provide detailed cross-sectional images, they may not distinguish soft tissue differences
as well as MRI. They are also expensive and not ideal for imaging during pregnancy due to the radiation
dose. Additionally, the high radiation exposure limits their frequent use, especially in non-critical cases.
Radiotherapy
● Risks
Radiotherapy uses high doses of ionising radiation to kill cancer cells, but it also poses serious risks to
healthy tissues surrounding the target area. There is a chance of secondary cancers developing years later
due to DNA damage in normal cells.
● Side effects
Common side effects of radiotherapy include fatigue, skin irritation or burns, nausea, and localised
pain. Depending on the area treated, it can also cause hair loss, digestive issues, or infertility. Some side
effects may be long-term or permanent, especially with high-dose treatments.
● Limitations
Radiotherapy is not suitable for all cancer types, particularly those that are widespread or resistant to
radiation. Precise targeting is essential, and even slight movement during treatment can reduce
effectiveness or increase side effects. It also requires specialised equipment and trained professionals,
limiting availability in some regions.
Health and Safety in the medical use of ionising and non-ionising radiation
technologies.
Aim C: Understand health and safety, associated risks, side effects and limitations of ionising and non-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. During this clinical placement, I will have
the opportunity to shadow the work of a qualified Radiographer and gain valuable hands-on experience in the
safe use of both ionising and non-ionising radiation technologies. Medical imaging techniques such as X-rays,
MRI, and ultrasound play a vital role in diagnosing, monitoring, and treating a wide range of health conditions.
These techniques rely on different forms of radiation, each with its own set of applications, risks, side effects,
and limitations. Ionising radiation, used in procedures like X-rays and CT scans, can pose health risks if not
managed properly, requiring strict safety protocols to protect both patients and healthcare professionals.
Non-ionising techniques, such as MRI, ultrasound, and infrared imaging, are generally safer but still require
careful use to avoid issues like tissue heating or problems with metal implants. Through my placement, I aim to
deepen my understanding of how these technologies work, recognise their potential hazards, and observe the
control measures in place to ensure safe and effective imaging. At the end of my placement, I will produce a
report to demonstrate my knowledge and understanding of these essential topics in preparation for my future
studies and career.
C. P5 Explain the health and safety risks, side effects and limitations of non-ionising and ionising
radiation technologies.
Ionising radiation
Risks
Ionising radiation carries several potential risks, especially due to its ability to damage living tissues and DNA.
One of the most significant risks is the increased likelihood of developing cancer from prolonged or repeated
exposure. Medical imaging techniques such as CT scans or X-rays use low doses of radiation, but cumulative
exposure over time can still be harmful. There's also a risk to healthcare workers who are repeatedly exposed to
radiation if proper shielding and protocols are not followed.
Side effects
The side effects of ionising radiation vary depending on the dose and part of the body exposed. In therapeutic
contexts like radiotherapy, patients might experience skin burns, fatigue, nausea, or damage to healthy tissues
,near the treatment site. Long-term side effects may include scarring, organ damage, or infertility if reproductive
organs are exposed. These side effects can sometimes outweigh the benefits, especially if not carefully managed.
Limitations
Despite its effectiveness, ionising radiation in medical physics has limitations. It is not suitable for all patients,
pregnant women and children are especially vulnerable. It also cannot distinguish between cancerous and
healthy cells without precise targeting, which can lead to collateral damage. Some diseases or injuries do not
show up clearly on radiographic images, limiting diagnostic accuracy. Furthermore, the infrastructure and
training required to safely use ionising radiation are costly, limiting access in low-resource settings.
Non-ionising
Risks
Although generally safer than ionising radiation, non-ionising radiation still presents some risks. For example,
prolonged exposure to strong electromagnetic fields, such as those used in MRI (Magnetic Resonance Imaging),
can induce currents in the body, potentially causing nerve or muscle stimulation. There’s also concern about the
heating effects of radiofrequency (RF) radiation, which can increase tissue temperature, especially in
high-intensity applications. Additionally, metallic implants or pacemakers can pose serious safety issues during
MRI scans.
Side effects
Side effects from non-ionising radiation are rare but can occur. Some patients report dizziness, nausea, or a
feeling of warmth during MRI procedures due to changes in magnetic fields or noise levels. In therapies like
ultrasound, if used improperly, localised tissue heating or cavitation formation of small gas bubbles can occur,
potentially leading to tissue damage. However, these effects are generally mild and avoidable with correct usage.
Limitations
Non-ionising radiation techniques also have several limitations. MRI scans, while very detailed, are expensive,
time-consuming, and not suitable for patients with certain metal implants. Ultrasound imaging, another
non-ionising method, is less effective for imaging areas surrounded by bone or gas like the brain or lungs.
Moreover, non-ionising methods often lack the resolution or depth penetration needed for diagnosing some
internal conditions, limiting their diagnostic range compared to ionising techniques like CT scans.
Ionising radiation (X-rays, CT scans, Radiotherapy)
X-rays
● Risks
X-rays involve exposure to ionising radiation, which can pose cancer risks over time if used repeatedly.
Although individual doses are relatively low, cumulative exposure, especially in medical staff or patients
undergoing regular scans, can be harmful.
, ● Side Effects
X-rays rarely cause immediate side effects, but prolonged exposure may result in localized tissue damage
or contribute to long-term health issues. In dental or chest X-rays, for instance, the risk is extremely low,
but still present.
● Limitations
X-rays are limited in how much detail they can provide, especially for soft tissues like the brain or
internal organs. They offer two-dimensional images, which can make it difficult to detect certain
abnormalities. Overlapping structures can obscure problems, and small tumors or early-stage diseases
may not be visible.
CT scans
● Risks
CT (Computed Tomography) scans expose patients to significantly higher doses of ionising radiation
than standard X-rays. Repeated scans over time can increase the risk of developing cancer, particularly
in younger patients or those who require frequent imaging. There is also a small risk of allergic reactions
to contrast dyes used during some scans.
● Side effects
Short-term side effects from CT scans are generally minimal but can include discomfort from lying still
for long periods or reactions to contrast agents, such as nausea, rash, or dizziness. In rare cases, contrast
dye may affect kidney function, especially in patients with pre-existing kidney problems.
● Limitations
While CT scans provide detailed cross-sectional images, they may not distinguish soft tissue differences
as well as MRI. They are also expensive and not ideal for imaging during pregnancy due to the radiation
dose. Additionally, the high radiation exposure limits their frequent use, especially in non-critical cases.
Radiotherapy
● Risks
Radiotherapy uses high doses of ionising radiation to kill cancer cells, but it also poses serious risks to
healthy tissues surrounding the target area. There is a chance of secondary cancers developing years later
due to DNA damage in normal cells.
● Side effects
Common side effects of radiotherapy include fatigue, skin irritation or burns, nausea, and localised
pain. Depending on the area treated, it can also cause hair loss, digestive issues, or infertility. Some side
effects may be long-term or permanent, especially with high-dose treatments.
● Limitations
Radiotherapy is not suitable for all cancer types, particularly those that are widespread or resistant to
radiation. Precise targeting is essential, and even slight movement during treatment can reduce
effectiveness or increase side effects. It also requires specialised equipment and trained professionals,
limiting availability in some regions.
