X-Ray and CT Scan Flashcards
What is an X-ray?
It creates images using x-rays, magnetic fields, sonar and radioactivity that allow doctor’s to make a diagnosis of a patient’s disease or injury.
What is an ‘x-ray’?
a photon (bundle of energy) which is essentially without mass and has no charge.
Is an x-ray a natural form of radiation?
No
Is an x-ray invasive or non-invasive?
non-invasive
How is an x-ray produced?
accelerating electrons toward a target.
What does CT stand for?
Computed Tomography
How does a CT work?
uses x-radiation to create higher resolution emages than a simple x-ray machine can produce alone.
What is a wave?
a vibration tha tis propagated through a medium such as air.
What is an electromagnetic wave?
is a vibration produced by the acceleration of an electric charnge.
List the steps of an x-ray.
step 1: elecrons are exposed to a potential difference in an x-ray generators. Electrons gain NRG so becomes kinetic energy.
step 2: electrons move quickly. causes release of x-rays.
step 3: x-rays pass through body. Image recorded digitally. Called radiograph.
What is an x-ray image called?
radiograph
For X-ray:
Light sections =
Dark sectons -
light sectins = dense sections; few x-rays pass through
dark sections = lesser density; more x-rays pass through
X-rays can show clear images of ____ but are ____ in their ability to see____.
- bone
- limited
- soft tissues
In general, more dense_____will be seen by____areas.
- tissue
- darker
For tissue:
dark spots =
light spots =
dark spots = dense
light spots = not dense
For CT scan:
Do you have to have a contrast agent?
Do you have to fast?
- yes
- yes (12 hours)
Is a CT scan invasive or non-invasive. What makes it such?
invasive because of the contrast agent
How does a CT scan work? What does it produce?
- lie on narrow table that slides into the center of the scanner.
- scanner rotates around patient and produces one cross section upon a full rotation
For CT scan:
You will be asked to hold your____and hold____.
- breath
- still
For CT scan:
YOu will be asked to remove_____ and _____.
- street clothing
- jewlery
For CT scan:
Can put multiple____together to create a ____image of the area being studied.
- tomographs
- 3D
What are CT scans helpful in determing the presence of?
cancer
What are CT scans highly sensitive to?
abnormalities in soft tissue
CT scans can see even the tiniest of ______.
-bone fragments
CT scans can help determine_____.
-bone mineral density
Which is 3D and which is 2D?
x-ray and CT scan
3D=CT scan
2D=x-ray
What does the patient do during an x-ray?
radiologic technologies positions the patient using alight source and a series of landmarks obrained by pressing various body parts to find reference points
When do you have to hold your breath during an x-ray?
- if examing the chest or abdomin
- not required for legs, arms, or head
For X-ray:
You may be asked to hold a_____position for a short period of time.
-akward
For X-ray:
____and ____must be removed.
- street clothes
- jewlery
X-rays are a type of _______?
-ionixing radiation
What two risks come with ionizing radiation?
1) liverate an electron from an atom making it an ion
2) low doses can increase risk of long term effects such as cancer
What does ALARA stand for?
As Low As Reasonably Achievable
True or False:
X-rays are used to diagnose many types of medical issues not otherwise visible to the human eye.
True
