Radiology

Question 0

1% of reaction produces protons of which only a small percentage actually do what?

Answer 0

Exit the lead tube housing

Question 1

99% of the energy produced by the reactions in an x-ray are given off as what two things?

Answer 1

Heat and light

Question 2

Emulsion contains silver halide crystals which when activated will turn?

Answer 2

Black, due to the development process

Question 3

The more x-ray to reach the film the more silver is activated and the?

Answer 3

Darker that are will become once processed

Question 4

Tissues will low absorption capabilities e.g air allow more x-ray to reach the film, meaning lots of silver reached the film, causing it to be?

Answer 4

Darker

Question 5

Tissues with high absorption capabilities e.g bone will allow fewer x-rays to reach the film so very little silver is activated therefore is will be?

Answer 5

Lighter

Question 6

What are the four primary densities found in the body?

Answer 6

Air
Fat
Water
Bone
Metal

Question 7

Absorption is primarily controlled by what 3 things?

Answer 7

Tissue thickness
Anatomic number
Cellular density
Note: the higher each of these are, the greater the absorption from the x-ray beam, the darker the the x-ray

Question 8

Does computer tomography (C.T) have ionising radiation?

Answer 8

Yes

Question 9

In a C.T what colour is cortical bone?

Answer 9

White

Question 10

What is a C.T measured in?

Answer 10

Hounsfield unit (HU) which represents density

Question 11

A CT scan can range from -1000 to 1000, with air being at the low end and cortical bone being up the top end, water is at?

Answer 11

0

Question 12

CT images can only be obtain in what plane of view?

Answer 12

Axial plane

Question 13

When the term “ isodense” is used in a C.T scan what does this refer to?

Answer 13

When one tissue is similar to another

Question 14

A C.T scan has two possible views, what are these?

Answer 14

Soft tissue window

Bone window

Question 15

In a C.T scan a soft tissue window is used to evaluate soft issue. Soft tissue detail is good and bone detail

Answer 15

Is not

Question 16

In a CT scan a bone window is used to evaluate bone, cortical bone is distinctly different to?

Answer 16

Medullary bone

Question 17

Does magnet resonance imaging (MRI) have ionising radiation?

Answer 17

No

Question 18

What plane can MRI be taken in?

Answer 18

Any

Question 19

How does an MRI work?

Answer 19

Hydrogen atoms in the body generate small magnetic fields which are randomly orientated, a radiofrequency pulse is sent into the patients body which brings the spinning hydrogen atoms into a phase. When the pulse is removed the coil measures the energy emitted at the H atoms relax back into a randome phase of spin,different tissues will relax at different times