Radiopharm Flashcards
Reducing agent
Substance that reduces another substance, by itself being oxidized
Chelating agent
a substance who molecules can form several bonds to a single metal ion.
ligand
a group ion or molecule coordinated to a central atom or molecule
antioxidant
a substance that inhibits ocidation or rxns promoted by oxygen, peroxides, or free radicals
oxidizing agent
a substance that gains electrons electrons in a chemical rxn, usually transfers oxygen to a substrate.
Hydrolyzed-Reduced Tc-99m
Particulate inpurity taht is insoluble Tc99 dioxide and/or Tc99m tin colloid
Free Tc99m
radionuclide that did not bind to the desired ligand.
Moly breakthrough
must be less than 0.15 microcuries per mCi of Tc-99m at the time of injection
Aluminum ion breakthrough test
litmus test
Ion Chamber
xrays, gamma rays, beta particles
argon gas
radiation dose rate in mrems/hour
Geiger Muller
contamination
argon gas
all types of radiation
Dose calibrator
measures the quantities of millicuries in a dose before giving to patient
argon gas
Wipe counter
highly sensitive (for small quantities of contamination.
thallium doped iodide crystal
Constancy
daily test for prescision and reproducibility
linearity
quarterly? meausres linear radiation at different doses for reliability
accuracy
annually
within 10%
Geometry
correct readings regardelss of size or geometery (every syringe sizewith diff volumes)
Bone scan
Indications
mest, osteo, stress fxs, pagets, altered bone physiology
Bone scan
agents
tc 99m mdp hdp pyp f18naf
Bone scan
adult dose
15-20mci
Bone scan
peds dose
eanm dosing chart
Bone scan
ciritical organ
bladder wall and gonads
Bone scan
excretion
50% renal in 4-6 hours
bone scan
drug rxn
bisphosphonates decrease uptake
F18 naf for bone
pet tracer
positron emission
half life 109.7 minutes
energy 633 kev and 511 kev
urinary excretion
10mci dose
MPS agents
TI 201 (thallium) Tc99 sestamibi Tc99m tetrafosmin Rb 82 (PET) N13 ammonia (PET)
MPS Thallium
1/2 life is 73 hours, biological is 19 days, effective for 48 hours
critical organs are thryroid and testes
can be used for viability as well
MPS sestamibi
ischemia
hepaobiliary clearance
6 hour half life
upper large intestine is critical organ
MPS tetrofosmin (myoview)
ischemia and ventricle function
passive lipophilic diffusion
5-33mci
6.03 hour half life
critical organ is gallbladder wall
hepatobiliary excretion
MPS rb 82
cardiogen 82
decays from strontium 82 wich has a half life of 25 days
half life of 75 seconds
40mci dose (30-60)
kidnes liver speen and lung are critical organs
N13 ammonia PET
myocardium under rest or pharmacologic stress
10-20mci
physical half ife of 9.96 minutes
bio 2.84 inutes
effective 2.21 minutes
photons 511 kev
Adenosine
stress agent
endogenous coronary vasodilator
T1/2 4-10 seconds
140mcg/kg/min
CI: av block, sinus node dz, bradycardia, asthma
Lexiscan
stress agent
low afinity for A2 adenosine receptor produces vasodilation and increased coronary blood flow
3 phase half life with intermediate of 30 minutes
ci are heart block, bradys, sinus node dysfunction
antidote is aminophylline
dipyridamole
stress agent
coronary vasodilator (increases flow by 4 times)
plasma 1/2 life of 30 minutes
antidote aminophylline
Dobutamine
stress agent
b1 agonist with increased cardiac output
1/2 life of 2 minutes
hold ccb and beta blockers
ci with cardiomyopahty aortic stneosis, constrictive pericarditis, peumonectomy, mi in last 30 days
antidote is esmolol
MUGA
evaluation of ventricular function
LVEF = (EDV -ESV)/ (EDV) X100
in vivo (pyp) and in vitro (tc99m) tagging of rbcs
pyp and tc99m
works by blood pool
I123 MIBG for cardiac studies
indicated for CHF mortality risk
dose is 10ci over 1-2 minutes, pretreat iwth sski
Iobenguane, pools in the adrenals, liver spleen, lungs, heart, salivary glands and neural crest tumors
Hepatobiliary scan
Tc99m lidofenin, disofenin, mebrofenin
ruq, acut chole, chronic chole, gbef, post chole leak, sod dysfunction
binds to albumin and carried to liver
npo for 4-6 hours but less than 24 hours
4-6 hours after narcotics
use morphine if you visualize the intesting but no gall bladder at 30-60 minutes. after admin if gallbladder is seen then chronic chole if not seen then acute
cck give 30 minutes prior if pt npo for > 24 hours. give during study to calculate GBEF. dont use after morphine
ensure plus 237 ml to ensure ef with no cck
phenobarbital with peds will be uptaken into biliary if just jaundixe wbut no uptake if biliary atresia..
disofenin
hepatolite
30mg/dl of bili
peak liver in 10 minutes
visualize gb or liver by 60 minutes
mebrofenin
choletec
hepatic and gb visualized in 10-15 minutes
instestinal activity at 30-60 minutes
contains presesrvatives
VQ scan indications
PE
COPD
PAH
Ventilation
Xe 133 or Tc99m DTPA
xe bio half life 30 seconds, physical 1/2 life 5.3 days, beta decay 81 kev, beforeperfusion, lipophilic, 15-25 mci lungs are critical
dtpa must be less than 3 microns, 5-10% of dose in nebulizer is actually delivered, delivered soe is 15mci, half life is 1 hour in the lungs
Perfusion
Tc99-m MAA
localized by capillary blockade
lung is critical organ
> 150 microns will clog arterioles
<10 microns will pass through the liver
reduce number of particles with right to let shunt, peds, pulm htn, pregnancy, pneumonectomy
brain imaging perfusion agents
Tc99m-exametazime (ceretec) HMPAO Tc99m bicisate (neurolite) ECD
PET: F-18FDG
DATscan (Ioflupane i23
Amyvid (florbetapir f18)
Tc99m ECD and HMPAO
HMPAO gets cobalt added with it and it becomes table for 5 hours
they are lipid soluble and can cross the bbb
F18 FDG brain perfusion
fdg glucose pass the BBB
8-12 mci
acetazolamide 250-500mg to produce cerebral venous dilation and increase flow
Datscan
ioflupane i123
suspected parkinsons vs essential tremor
binds to dopamine transporters in the substantia nigra
3-5 mci with sski
urine elimination
spect 3-6 hours later
halfl ife 13.2
ci with ssrisamphatime, amoxapine, benztropine, bupropion, cocaine, fentanyll, norepi, ritalin
amyvid
Florbetapir F18
pet imaging to estimate beta amyloid in alzheimer vs of causes of cognitive decline
binds to beta amyloid plaques and produces a positron
10 mci
gb > colon > small intestine > liver for critical organ
biliary elimiination
Liver/spleen scan
tc99m SC 5mci
goes to kupferr cells in the liver, macrophages in the spleen and the bone marrow
use a filter to get out particles that are too large.
lung upake if collodial clumping
0.1-1 micron diameter
