Brainscape's Knowledge GenomeTM

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


See full index

Body Logistics - Bethany B. > An intro to Medical Imaging > Flashcards

An intro to Medical Imaging Flashcards

1
Q

transverse plane

A

magician cut i half legs separated from top

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

coronal plane

A

crown cut separate bac of head from face

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

sagittal plane

A

90 degrees to coronal

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

How do x-rays give an image?

A

Focus the beam of high energy electronsthey pass through the body onto the receiver some are absorbed or scattered (attenuation)depends upon density and atomic number (metals)

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

Attenuation

A

how much you attenuate the x ray depends on the density and atomic number more dense/ higher atomic number = more attenuation= lighter appearance

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

Advantages of x ray

A

quick simplecheap portable

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

disadv of x ray

A

radiation but low one plane so 2Dwould not see all pathology cant visualise all areas poor soft tissue imaging

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

uses of x ray

A

chest- infection, pneumothroax, trauma, effusion, oedema bowel- dilatation, perforation orthopaedic- fracturepost procedure- nasogastric tube pacemaker PICCdentist

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

What contrast is used in fluoroscopy?

A

barium, iodine or gadolinium (MRI) - Strongly absorb x-rays - dense white -any space it can be swallow, inserted or injected

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

uses of fluroscopy

A

angiography contrast GI studies therapeutic joint injections
arthrograms screening in theatre

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

adv of fluroscopy

A

dynamic studies cheap interventional procedures

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

disadv of fluroscopy

A

clinical exposure must be minimised radiation

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

CT

A

computerised tomography

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

How does CT work?

A

rotating gantry-x-ray on one side -detectors on the other images put together by computer attentuation- higher atomic number- more attentuation-lighter image

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

Hounsfield units

A

less dense= negative
fat air black more dense= positive
bone metal water = 0

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

Looking at CT scans

A

looking from feet upleft side of image= right side of body

spine is posterior

17
Q

What is on the right side of the body?

A

liver kidney appendix gallbladder

18
Q

What is on the left side?

A

spleen kidney

19
Q

Adv of CT

A

QUICK good spatial resolution can scan most spaces

20
Q

disadv of CT

A

radtiation lower contrast resolution- harder to distinguish between different densities affected by artefactsrequires breath holding overuse fishing for diagnosis incidental findings

21
Q

How does an MRI work?

A

strong magnetic field aligns hydrogen atoms some point towards head some towards feet not all unmatched ions remain radio frequency pulse applied unmatched ions absorb energy and spin in opposite direction pulse is turned off and atoms spin returns which emits energy computer processing to generate image

22
Q

adv of MRI

A

no radiationgood contrast resolution - can distinguish between densities easily

23
Q

disadv of MRI

A 
expensive 
time consuming
availibility
claustrophobic 
some patients wont fit 
loud
need to stay still metalwork
24
Q

scintigraphy

A

injections of radiopharmaceuticals emmit gamma rays highly sensitive functional and anatomical info

25
Q

how does Position emmision tomography work?

A

pet scan radio nucleotides that decay by position emmision bound to glucose pet scan camera detects annihilation (high energy gamma rays) -more annihilations the bigger the signal-tend to be combined with CT/MRI’hot spots’- areas that highly metabolic reactive- glucose- these show up very bright usually used in oncology as cancer cells are very metabolically active

26
Q

Ultrasound

A

high frequency sound waves from transducer probethis sound wave is reflected by tissues where density (impedance) differs probe detects sound waves this creates an electrical signal-determines the distance- time taken to come back-determines impedance- proportion of reflected waves

27
Q

What is acoustic impedance?

A

an area where the density of tissues changes is where a lot of waves are reflected back

28
Q

What is acoustic shadowing?

A

great difference in tissue density means sound is completely reflected therefore cant see behind bone, air and stone

29
Q

what is hyperechoic

A

More reflectivewhite

30
Q

what is hypoechoic

A

less reflective dark grey

31
Q

anechoic

A

not reflective black- pure fluid

32
Q

adv of ultrasound

A

lack of ionising radiationlow cost portablecan be inserted into body cavaties babies dynamic (blood flow)

33
Q

disadv of Ultrasound

A

operant dependant no bone or gas penetration body habitus

34
Q

What are the ideal conditions for contrast media?

A

low osmolality and viscosity high water solubility biologically inert safeheat and chemically stablecost effective 95% glomerular filtrationtubular excretion and protein binding negligible half life: 30-60 minsyour kidneys need to be functional to allow the drug to be excreted

35
Q

What is an idiosyncratic reaction?

A

not predictable and rare

Body Logistics - Bethany B. (4 decks)

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