6/3/25 Radiology Intro and Safety

Question 1

What field of diagnostic medicine uses various methods of medical imaging to diagnose and treat diseases of the body?

Answer 1

Diagnostic radiology

Question 2

What are the 2 subspecialties of radiology?

Answer 2

Diagnostic radiology (diagnosis)
Intervention radiology (treatment)

Question 3

What imaging modalities are considered conventional radiography?

Answer 3

Radiography (X-ray)
Fluoroscopy
Conventional angiography
Mammography

All use radiation

Question 4

What imagine modalities are considered cross-sectional?

Answer 4

Conventional tomography (CT/CAT)
Ultrasound
MRI

Only CT uses radiation

Question 5

What imaging modalities are considered molecular/physiological imaging?

Answer 5

Nuclear medicine

Question 6

How does conventional radiology allow visualization of the body?

Answer 6

Uses radiation to generate images

Question 7

How do cross-sectional modalities allow visualization of the body?

Answer 7

Through production of cross sectional images of the body by obtaining information about a 2D volume/slice of patient tissue to produce a 3D

Question 8

Describe how CT scans are performed.

Answer 8

Uses radiation (x-rays) passing though the patient tissue to gather information and mathematically reconstruct a cross sectional image

Question 9

Describe how ultrasounds are performed.

Answer 9

They do no not use radiation, but rather turns electricity into sound waves which it uses to transmit into patient’s tissues via a transducer probe

Question 10

Describe how MRIs are performed.

Answer 10

Does not use radiation, but rather uses magnets to pass a magnetic field through a patient’s tissue which generates an image.

Question 11

What modality involves administeration of radioactive tracers/pharmaceuticals into the patient to view the radiation?

Answer 11

Nuclear Medicine (PET scans)

Question 12

What are radiotracers?

Answer 12

Radioactive substances that can mimic other substances in the body (sugar, blood, air, bile) so the radiologist can see how those substances are being distributed.

Question 13

What is a medication that can help improve soft-tissue contrast and visualization of body parts?

Answer 13

Contrast

Question 14

How can contrast be introduced into the body?

Answer 14

Intravenously (liquid), orally (tablet, liquid), or gas

Question 15

If you are allergic to one type of contrast for a certain modality, does that mean you are allergic to all types of contrast?

Answer 15

No, each modality typically uses a different contrast

Question 16

What is CT/X-ray contrast typically made of?

Answer 16

Iodine

Question 17

What is a common fluoroscopic contrast agent?

Answer 17

Barium sulfate (drinkable or eaten)

Question 18

What is the mode of action for Barium sulfate?

Answer 18

Coats the GI mucosa and gives definition to the gastric wall

Question 19

What is a common MRI contrast agent?

Answer 19

Gadolinium

Question 20

What is a common ultrasound intravascular contrast agent?

Answer 20

Microbubbles of air/gas within proteins.

Mimics/behaves like RBCs

Question 21

What certain things in the body are better visualized with contrast?

Answer 21

Lesions, soft tissue organs, blood vessels

Question 22

What is PACS?

Answer 22

Picture archiving and communication system. Used for conventional storage and access to images

Question 23

What are the roles of the technologists?

Answer 23

Obtain diagnostic images
Proper patient positioning
Radiation Safety
Patient care

Question 24

What is the role of radiology nursing support staff?

Answer 24

To monitor the patient during procedure

Question 25

What is the role of the medical physicists?

Answer 25

To optimize protocols/imaging techniques, troubleshoot, and can assist in fixing scanners

Question 26

What is the role of the vendor support staff?

Answer 26

Technical repair of instrumentation

Question 27

What are the roles of the radiologists?

Answer 27

Assist with ordering Provide diagnostic information Provide interventions Monitor patient safety Monitor appropriateness of imaging

Question 28

What is the role of radiology PA/NP?

Answer 28

Ordering imaging Assisting/performing therapies or procedures

Question 29

Define radiation modalities

Answer 29

The imagining method used for disgnosis

Question 30

What exactly is radiation?

Answer 30

The transfer of energy from unstable atoms in the form of waves and particles through space or an absorbing medium

Question 31

What is radiation which does not carry enough energy to ionize (remove an electron) from an atom or molecule?

Answer 31

Non-ionizing radiation

Question 32

What are some examples of non-ionizing radiation?

Answer 32

Visible light Infrared Radio waves Cell phones

Question 33

Does non-ionizing radiation cause tissue damage?

Answer 33

Not that we know of

Question 34

What is radiation which has sufficient energy to break apart chemical bonds/change the chemistry of a target?

Answer 34

Ionizing radiation

Question 35

Ionizing Radiation: Direct damage

Answer 35

Damage to DNA

Question 36

Ionizing Radiation: Indirect damage

Answer 36

Creates a free radical which is chemically reactive and can damage biological tissue

Question 37

What is radiobiology?

Answer 37

The study of effects of ionizing radiation in cells and animal models

Question 38

What is background radiation?

Answer 38

Ionizing radiation present in the environment

Question 39

What are some examples of natural background radiation?

Answer 39

Internal radiation (body generated) Food/Drinks Terrestrial radiation (buildings, dirt) Cosmic radiation (from space)

Question 40

What are some examples of artificial background radiation

Answer 40

Consumer items (cigarettes) Occupational exposure Medical imaging Atmospheric exposure (nuclear testing)

Question 41

What are the ways to measure radiation dose?

Answer 41

Equivalent dose Effective dose

Question 42

Define effective dose

Answer 42

Accounts that radiation results in a nonuniform distribution on the body (dose for all exposed organs)

Question 43

What is the unit of measurement for the radiation dose?

Answer 43

Sievert (Sv) 1 Sv= 1 joule/kg

Question 44

Direct effect of radiation depends on what?

Answer 44

Dose. The greater the dose, the greater the effect

Question 45

As radiation dose increases, the chance (probability) of a stochastic effect (like getting cancer) ______. Increases or decreases

Answer 45

Increases

Question 46

Does radiation affect cancer severity?

Answer 46

No, only affects the probability (chance) of getting cancer

Question 47

The most widely used estimate of risk of cancer induction due to ionizing radiation is __% per Sv.

Answer 47

5%

Question 48

A high dose of radiation (______ mSv) is known to increase the risk of cancer

Answer 48

>100 mSv

Question 49

Head CT radiation dose

Answer 49

up to 3 mSV

Question 50

Abdomen/Pelvis CT radiation dose

Answer 50

Up to 5 mSv

Question 51

Chest/Abdomen/Pelvis CT radiation dose

Answer 51

Up to 10 mSv

Question 52

Why are children more sensitive to the potential harmful effects of radiation?

Answer 52

Their bodies are still developing, and the rapidly dividing cells are more susceptible to damage by radiation

Question 53

Cancer risk for a 4 year old is ___ to ___ times more likely than a 40 year old

Answer 53

3 to 5 times more likely

Question 54

What is the overall risk of cancer over a person's lifetime?

Answer 54

20-25%

Question 55

What is the estimated lifetime cancer risk from a single CT?

Answer 55

0.03-0.05% (1 in 2000 chance of developing cancer associated with imaging study)

Question 56

What does ALARA stand for?

Answer 56

As low as reasonably achievable

Question 57

Why is ALARA important?

Answer 57

It is a guiding principle to keep radiation exposure as low as possible for each procedure while obtaining the needed clinical information

Question 58

What medical equipment can lower your risk to radiation during procedures?

Answer 58

Aprons, dosimeters, goggles, gloves

Question 59

When possible, how far away should you stand from the radiation source?

Answer 59

3 feet

Question 60

What is the ACR appropriateness criteria?

Answer 60

A clinician support tool that provides info on relative radiation dose for suggested diagnostic exams. .