Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MODULE 6 > RADIOLOGY - other modalities > Flashcards

RADIOLOGY - other modalities Flashcards

1
Q

what are the other modalities in radiology?

A

CT
MRI
ultrasound
nuclear medicine
combination - PET-CT/ PET MRI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what may be used to increase soft tissue contrast when taking a CT scan?

A

iodinated contrast intra-venously

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what shape is the beam for a CT scan?

A

fan shaped

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what position is the patient for a CT scan?

A

lying horizontal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what do newer CT units use instead of normal voxels? and what are the advantages of these?

A

isotropic voxels
allow for manipulation of images in all 3 planes with no distortion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what value is given to CT voxels?

A

Hounsfield units

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the hounsfield numbers for the tissues a CT scans?

A

air -1000
fat -100 to -60
water 0
dense bone +1000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how do hounsfield numbers correlate with colour?

A

-1000 black
+1000 white

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is windowing in CT scan?

A

alters levels of densities visualised in scan to optimally look at specific tissues

window level: value at centre of range
window width: range of values selected to view tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the equivalent of radiation dose from a bitewing to natural background?

A

less than 1.5 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the equivalent of radiation dose from a CT head to natural background?

A

1 year

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how is an MRI taken?

A

whole room is a magnetic field
imaging coil is placed over a region of interest to gain higher resolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what colour is cortical bone, fat, and fluid in an MRI?

A

cortical bone - black
fat - white
fluid - white

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are the advantages of an MRI?

A

no ionising radiation
very good imaging of soft tissues and early changes in bone marrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are the disadvantages of an MRI?

A

multiple contraindications
lengthy scans
claustrophobia
cost

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the contraindications for MRI?

A

pacemakers
orbital foreign bodies
artificial heart valves
surgical clips

17
Q

what can MRI be used for in dentistry?

A

TMJ degeneration
salivary glands
sinuses for malignancies

18
Q

how does an ultrasound produce image?

A

high frequency sounds waves
transducer placed on skin surface with coupling agent between probe and skin to penetrate waves

length of time it takes for sound waves to return will create level of depth

19
Q

what can sound waves not penetrate?

A

dense bone

20
Q

what are the advantages of ultrasound?

A

no ionising radiation
good for superficial structures
real time imaging
can be used in adjunct to biopsy/ aspirates
blood flow

21
Q

what are the disadvantages of ultrasound?

A

operator dependent
cant penetrate bone
can be difficult to interpret
only superficial structures seen

22
Q

what are examples of ultrasound use in the head and neck?

A

neck lumps
salivary glands
vascular

23
Q

what type of neck lumps may you want to ultrasound?

A

cysts
tumours
lymph nodes

24
Q

what salivary gland disorders may you want to ultrasound?

A

sjogrens
neoplasia
sialadenitis
sialoliths

25
Q

what type of vascular diseases may you want to ultrasound?

A

carotid artery stenosis
vascular lesions

26
Q

what are the types of nuclear medicine?

A

PET
SPECT
Scintigraphy

27
Q

what is nuclear medicine?

A

patient is injected intra-venously with radiopharmaceutical which when it decays emits particles that are picked up on a gamma camera

increased activity - hot spot
reduced/ no activity - cold spot

28
Q

what are the advantages of NM scans?

A

can be superimposed over other cross sectional imaging
highly sensitive
can assess function

29
Q

what are disadvantages of NM scans?

A

poor resolution
poor specificity
very high radiation dose

30
Q

what are the 2 types of rasioisotopes?

A

TECHNETIUM-99M
18-FDG

31
Q

what is a PET-CT?

A

type of nuclear medicine scan superimposed over conventional CT

32
Q

what are PET CTs used for?

A

cancer diagnosis

MODULE 6 (67 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions