Brainscape's Knowledge GenomeTM

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


See full index

phm 501: foundation > diagnostic imaging > Flashcards

diagnostic imaging Flashcards

1
Q

anatomic imaging

A
  • x-ray: CT
  • MRI
  • ultrasound
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

functional imaging

A
  • SPECT
  • PET
  • ultrasound
  • MRI
  • CT
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

x-ray

A
  • machine produced, external source of radiation
  • originally exposed a piece of film
  • now, mostly digital
  • image still produced due to different tissue densities
  • structures superimposed
  • bedside capability
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

computerized tomography (CT, CAT)

A
  • machine produced, external source of radiation (x-ray)
  • tomographic reconstruction
  • image produced due to different tissue densities
  • contrast media often used to enhance image
  • mobility challenges
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

magnetic resonance imaging (MRI)

A
  • no radiation
  • contrast media used
  • claustrophobic (less so than in past)
  • ferrous metal is a problem
  • motion is a problem (length of scan)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

ultrasound

A
  • uses sound wave to image
  • no radiation
  • bedside capability
  • technically demanding (operator sensitive)
  • can’t see through air
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

radiopacity

A
  • not penetrable by x-rays
  • bone is radiopaque
  • most soft tissues are difficult to see with x-rays because they are relatively radiolucent
  • exogenous iodine first substance shown to allow visualization of a hollow organ (bladder) via x-rays
  • studies of iodine for the treatment of syphilis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

iodinated contrast media

A
  • iodine is radiopaque
  • toxicity limited early use
  • administered IV (or by direct instillation into the bladder)
  • allow visualization of vascular anatomy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

coronary angiography

A
  • coronary anatomy

- ventricular function cine (EF, wall motion)

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

iodinated contrast media: CT use

A
  • enhance image

- angiography

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

iodinated IV contrast media: adverse effects

A
  • 25% of patients (conservatively): flushing, heat, pain
  • renal dysfunction, hypotension, dysrhythmia*
  • anaphylactoid reactions*
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

iodinated IV contrast media: precautions

A
  • prior AE with ICA
  • CVD
  • renal disease (SrCr >2.5 mg/dl)
  • dehydration
  • hay fever/asthma/multiple allergies
  • concurrent beta blockers
  • metformin use (increase risk of lactic acidosis)
  • concurrent renally toxic drugs
  • low-osmolality agents have lower AE rate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

iodinated IV contrast media: pretreatment

A
  • hydration
  • nAcetylcysteine 600mg BID x 2 days
  • corticosteroids +/-
  • antihistamines
  • sodium bicarbonate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

reduction in osmolality

A

-goal with iodinated IV contrast media

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

MRI challenges

A
  • claustrophobia

- metal = implants, patches (take off)

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

MRI contrast media: gadolinium based

A
  • AE of gadolinium contrast: pregnancy warning, nephrogenic systemic fibrosis (NSF)*
  • avoid in patients with impaired renal function
17
Q

ultrasound

A
  • sound waves sent from a transducer
  • reflected signal measured
  • anatomy: cardiac, other
  • Doppler Flow: vessels, esp TCD, heart
18
Q

ultrasound contrast agents

A
  • GI: SonoRx (Bracco) = simethicone coated cellulose

- vascular in development = microbubbles

19
Q

GI anatomic imaging: DI with barium

A
  • no concurrent drug administration
  • potential for interaction with drugs that alter GI motility
  • particular concern with drugs that slow GI motility
20
Q

OTC products

A
  • bowel contents can obscure target organs

- solution? evacuate the bowel

21
Q

variety of “bowel preps”

A
  • “bowel prep” = extreme laxative
  • NOT bulk forming laxatives
  • NOT stool softeners
  • osmotic
  • stimulant
  • mechanical
22
Q

OTC prep kit: “fleet’s kits”

A

bisacodyl PO
+/- bisacodyl suppository
+/- enema
-+/- phosphate or magnesium laxative

23
Q

OTC prep kit: counsel

A
  • timing: don’t take at bedtime
  • GoLytely: administered cold
  • clear liquids
24
Q

radiation safety: safety dose?

A
  • dose response relationship
  • minimize amount of time around radioactive stuff
  • shielding
  • distance
25
Q

rad

A

radiation absorbed dose

26
Q

rem

A

roentgen equivalent, man

27
Q

imaging procedures

A

1 rad = 1 rem

28
Q

radiation risks: exposure

A

onset of radiation sickness = 75,000 mrad

29
Q

radiation toxicity

A
  • 210 Polonium
  • alpha emitter
  • Rx (theoretical): chelation
30
Q

radiation protection: iodine

A
  • iodine does NOT treat radiation exposure
  • BLOCKS uptake of radioactive iodine
  • needs to be dosed prior to exposure
  • other agents: amifostine
31
Q

functional imaging: SPECT

A
  • single photon emission computed tomography
  • readily available
  • uses radiation
32
Q

PET

A
  • positron emission tomography
  • does NOT image positrons
  • positron/electron interaction results in 2, 511 kEv photons
  • not readily available
  • uses radiation
33
Q

SPECT vs PET

A
  • single photo emitters have lower energies

- PET emitters have higher energies, much shorter half life than SPECT

34
Q

perfusion (Q)

A
  • measured by IV macro aggregated 99m Tc-albumin particles
  • these particles lodge within the lungs
  • in patients with severe pulmonary disease, either have to mitigate the dose or not do the test
  • Pulmolite, Macrotec, Draximage, Technescan MAA)
35
Q

match/mismatch

A
  • ~100% sensitivity in PE

- other vascular abnormalities can also give positive readings (pulmonary vasculitis)

36
Q

renal function: GFR

A
  • 99m Tc-diethylenetriamine pentaacetic acid (DTPA) infusion or injection
  • 125 I-iothalamate (Glofil)
37
Q

renal imaging: effective renal plasma flow (ERPF)

A
  • complete 1st pass extraction through kidney
  • p amino hippurate (PAH) analogs
  • 99m Tc-mercaptoacetyltriglycine (Technescan-MAG3)*
38
Q

ACE inhibitor challenge

A
  • dx of renal artery stenosis (renovascular HTN)
  • renal perfusion pressure maintained by RAS
  • administering ACE inhibitor disrupts RAS
  • decrease RPR
  • results in RETENTION of tracer
39
Q

Captopril challenge slide

A
  • stenosis

- retention of the tracer in the patient when they are on an ACE inhibitor vs when they are off an ACEi

phm 501: foundation (3 decks)

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