Introduction To Medical Imaging

Question 1

Radiology

Answer 1

Branch of medicine concerned with use of radiant energy/ radioactive material in the diagnosis and treatment of disease.

Question 2

Radiologist

Answer 2

Trained to interpret diagnostic images and perform some specialist tests

Question 3

Radiographer

Answer 3

Trained to take/ perform X-ray, CT, MRI etc.

Question 4

Sonographer

Answer 4

Trained to perform ultrasounds

Question 5

Angioplasty

Answer 5

Insertion of a balloon into a vein/artery to widen it and improve circulation.

Question 6

Stenting

Answer 6

Insertion of a tube to keep an artery or vein open

Question 7

Biopsies

Answer 7

Lung, breast, renal, liver, bone etc.

Question 8

Clinical Oncologist

Answer 8

Specialised physician who uses radiation in the treatment of cancer.

Question 9

Order of e/m spectrum from lowest to highest frequency

Answer 9

R, M, I, V, U, X, G

Question 10

X-ray

Answer 10

A form of e/m radiation which is able to pass through the human body and produce an image of internal structures.

Question 11

Radiograph

Answer 11

X-ray / plain film

Question 12

How is bone represented on an X-ray ?

Answer 12

Greyish, White colour

Question 13

How is air represented on an X-ray ?

Answer 13

Black

Question 14

Order of colours on an X-ray from darker to lighter

Answer 14

Air
Fat
Soft tissues / water
Bone
Contrast material / metal

Question 15

Mammography

Answer 15

Uses a low-dose X-ray system
Designed for creating detailed images of the breast
Used as screening to detect early breast cancer without signs/symptoms or diagnose breast disease with symptoms

Question 16

Fluoroscopy

Answer 16

Shows a continuous x-ray image on a monitor, used where real time examination is required.
e.g. positioning of implants during surgery
e.g. viewing the movement of contrast agents like barium
e.g. studying movement of body parts

Question 17

Angiography

Answer 17

Used in the examination of the arteries/veins.
Angiograms usually carried out by IR.

Contrast agent injected to make blood vessels visible on the X-ray image.

Question 18

CT scan

Answer 18

Computed Tomography

Question 19

Uses of CT scan

Answer 19

Produces images of single tissue planes.
Provides cross-sectional imaging/slices of anatomy

Question 20

Advantages of CT scan (3)

Answer 20

Fast
Readily Available
Good imaging of bony structures, abdomen and lungs

Question 21

Disadvantages of CT scan (3)

Answer 21

High radiation Dose
Not so good at imaging soft tissue (brain, spinal cord, muscles)
High Resource use (staffing, time, space)

Question 22

Scintigraphy Nuclear Medicine

Answer 22

Use of gamma radiation to form images following the injection of various radiopharmaceuticals

Question 23

Metastable

Answer 23

Where the technetium actor has 2 basic energy states : high and low

Question 24

Advantages of Scintigraphy

Answer 24

High Sensitivity
Provides functional information

Question 25

PET scan

Answer 25

Coloured Combination of CT and scintillation scanning

Question 26

MRI

Answer 26

Magnetic Resonance Imaging

Question 27

Disadvantages of Scintigraphy

Answer 27

High Radiation Dose Cancer vs Infection looks same on scan

Question 28

What is special about MRI ?

Answer 28

NO ionising radiation

Question 29

What does MRI use ?

Answer 29

VERY powerful superconducting magnet that creates a static magnetic field.

Question 30

What causes the tapping sound in an MRI machine ?

Answer 30

Radio signal being turned on and off

Question 31

What is high signal intensity ?

Answer 31

White

Question 32

What is intermediate signal intensity ?

Answer 32

Grey

Question 33

What is low signal intensity ?

Answer 33

Black

Question 34

T1 weighted MRI

Answer 34

Highlights fat tissue within the body

Question 35

What does intensity mean in MRI ?

Answer 35

The shade of grey of tissues and fluid.

Question 36

T2 weighted MRI

Answer 36

Highlights fat and water within the body

Question 37

Advantages of MRI

Answer 37

Gold Standard of Imaging No radiation Good differentiation between pathologies Excellent soft tissue imaging esp in brain & spinal cord

Question 38

Disadvantages of MRI

Answer 38

Potentially dangerously strong magnet Not good for bone High cost Long duration of scanning Need for anaesthesia in younger/uncooperative patients

Question 39

Ultrasound Imaging

Answer 39

Uses sound waves to create an image

Question 40

Types of Imaging

Answer 40

X-ray CT scan Nuclear Medicine MRI Ultrasound

Question 41

Advantages of Ultrasound

Answer 41

Safe No ionising radiation Portable equipment, compact and inexpensive

Question 42

Disadvantages of Ultrasound

Answer 42

Highly operator dependent Structures surrounded by bone e.g. brain/spinal cord don't give clinically useful images

Question 43

Causes of wasteful requests

Answer 43

Repeat investigations Doing wrong investigation Investigating too often

Question 44

What 2 types of imaging use no ionising radiation ?

Answer 44

MRI and Ultrasound