Nucs Flashcards
Half life of Tech-99m?
energy?
6 hrs
“low” 140
Half life of I-131
Energy?
8 days
“High” 365
Half life of I-123?
Energy?
13 hrs
“low” 159
Half life of Xenon-133
Energy?
5.2 days/125 hours, biologic is 30 seconds
“low” 81
Half life of F-18
Energy?
110 min
“High” 511
Which technetium radiopharmaceutical is used for Meckel’s, salivary, and thyroid?
Tc-99m sodium pertechnetate
Which technetium radiopharmaceutical is used for liver, spleen, and bone marrow?
Tc-99m sulfur colloid
Which technetium radiopharmaceutical is used for acute MI?
Tc-99m pyrophosphate
Which technetium radiopharmaceutical is used for msk?
Tc-99m diphosphonate
Which technetium radiopharmaceutical is used for pulm perfusion?
Tc-99m MAA
Which technetium radiopharmaceutical is used for GI bleed?
Tc-99m red blood cells
Which technetium radiopharmaceutical is used for measuring GFR, renal scintigraphy?
Tc-99m DTPA (diethylenetriamin-pentaacetic acid)
Which technetium radiopharmaceutical is used for renal dynamic scintigraphy?
Tc-99m MAG3 (mercaptoacetyltriglycine)
Which technetium radiopharmaceutical is used for renal cortical scintigraphy?
Tc-99m DMSA (dimercaptosuccinic acid)
Which technetium radiopharmaceutical is used for hepatobiliary scintigraphy?
Tc-99m iminodiacetic acid (IDA/HIDA derivs)
Which technetium radiopharmaceutical is used for myocardial perfusion?
Tc-99m tetrofosmin, teboroxime, and sestamibi
Which technetium radiopharmaceutical is used for cerebral perfusion?
Tc-99m HMPAO (examaetazime) and ECD (bicisate)
Which technetium radiopharmaceutical is used for WBC labeling?
Tc-99m HMPAO
Which single photon radiopharmaceutical is used for myocardial perfusion?
thallium
Which single photon radiopharmaceutical is used for inflammatory dz detection?
gallium or In-111 labeled WBCs
Which single photon radiopharmaceutical is used for pulmonary ventilation scint?
Xe-133 and Xe- 127
Which single photon radiopharmaceutical is used for graves dz and thyroid ca?
I-131
Which single photon radiopharmaceutical is used for thyroid scint., thyroid uptake fxn studies?
I-123
Which single photon radiopharmaceutical is used for adrenal medullary imaging, neural creast tumors?
MIBG (I-131, I-123 metaiodobenzyl guanidine)
The fetal thyroid can concentrate radioiodine at how many weeks?
10-12 weeks
How long does a lactating mother need to wait to breastfeed after the administration of I-131?
Breastfeeding is terminated altogether.
How long does a lactating mother need to wait to breastfeed after the administration of I-123?
Can resume breastfeeding after 2-3 days.
How long does a lactating mother need to wait to breastfeed after the administration of Tc-99m agents?
12-24 hrs
What is the annual dose limit for radiation exposure: adult occupational total effective dose equivalent?
0.05 Sv (5 rem)
What is the annual dose limit for radiation exposure: adult occupationalto any organ or tissue or extremity?
0.5 Sv (50 rem)
What is the annual dose limit for radiation exposure: adult occupational to the lens of the eye?
0.15 Sv (15 rem)
What is the annual dose limit for radiation exposure: minors occupational?
10% of those for the adult
What is the annual dose limit for radiation exposure: embryo/fetus occupational during pregnancy?
5 mSv (0.5 rem)
What is the annual dose limit for radiation exposure: members of the public?
1 mSv (0.1 rem) or 0.02 mSv in any hour
Half life of In-111?
67 hrs
Dose calibrators, how often do they need to be quality control tested and what do they look like?
Looks like a calculator. Annual accuracy, quarterly linearity, and daily constancy testing.
In neonatal hepatitis, when should you image to look for biliary atresia?
At 24 hrs. (100% sensitive)
What is the appropriate dose for sincalide? What is it used for?
0.02 ug/kg to evaluate gallbaldder EF in the settting of chronic cholecystitis
Half life of Ga-67?
78 hrs
What drug can you use to reverse the vasodilatory side effects of dipyridamole and regadenosine?
aminophylline
What dose of phenobarbitol is used to evaluate biliary atresia in a newborn?
5 mg/kg/day PO BID min 3–5 d before hepatobiliary imaging
Half life of Rubidium 82?
75 seconds
Half life of TI-201 Thallus chloride
73 hours
What is the affect of dipyrimadole on the coronary arteries?
indirect coronary artery vasodilator that increases the tissue levels of adenosine by preventing the intracellular reuptake and deamination of adenosine.
What scan is it?
you see: bones and spleen
*whole body
WBC
What scan is it?
you see: bones, spleen, liver
*whole body
Sulfur colloid
What scan is it?
You see: bones, liver, salivary/lacrimal glands
*whole body
Gallium
What scan is it?
You see: heart and kidneys
(no bones pathway)
MIBI.
*sestamibi is the main cardiac tracer, so there’s got to be a heart. The other one with a heart (+/-) is MIBG, and MIBG is for evaluating neuroblastoma. Better not have kidneys in the way when you evaluate neuroblastoma.
What scan is it?
You see: heart
(no bones pathway)
MIBG
*sestamibi is the main cardiac tracer, so there’s got to be a heart. The other one with a heart is MIBG (+/-), and MIBG is for evaluating neuroblastoma. Better not have kidneys in the way when you evaluate neuroblastoma.
What scan is it?
You see: nothing
(down no bones pathway, no heart)
Iodine
What scan is it?
you see: liver
(down no bones no heart pathway whole body)
MIBG
*heart is variable in MIBG. Some radiologists care about kids with neuroblastoma and have a heart, others do not.
What scan is it?
you see: super hot spleen and super hot kidneys
Octreotide
What nucs study will help you identify hibernating myocardium?
Cardiac defect that redistributes on delayed thallium imaging.
How frequently is a dose calibrator checked for linearity?
quartery
How much residual activity before you can leave hospital ith I-131 tx?
33 mCi (30 in some stricter states)
after I-131 tx, how long do you have to wait to get pregnant?
6-12 months
what medicines can be used to treat hyperthyroidism? (no such thing as emergent hyperthyroid treatment)
and in pregnancy?
Methimazole
or if pregnant PTU
MC cause of hyperparathyroidism?
hyperfunctional adenoma (85%)
Dual tracer technique for parathyroid?
1st agent is Tc99 Sestamibi or 201 Thallium chloride- these agents go to BOTH thyroid and parathyroid
2nd agent I-123 or Pertechnetate.
Subtract
Everything left hot could be a parathyroid adenoma
What is the anatomic localization difference between HMPAO (hexamethylpropyleneamine oxime) and ECD (ethyl cysteinate dimer)?
HMPAO favors the frontal lobe, thalamus, and cerebellum
ECD favors the paretal and occipital lobes
What radiotracers are preferred for brain death studies?
HMPAO and ECD (lipophilic brain perfusion specific) but DTPA can also be used.
All attached to Tc99
How sensitive is tagged RBC scan for GI bleed?
detects at 0.1 mL/min
Angiogram detects 1.0 mL/min
What meds can you use prior to to a meckel scan to make it prettier?
slow down motility with glucagon
make the pertechnetate stick around longer by H2 blocker (cimetidine and ranititine)
enhance uptake of tech by gastic mucosa with pentagatrin
dose of CCK?
0.02 microgram/kg over 60 mins
dose of morphine for hida?
0.02-0.04 mg/kg over 30-60 mins
in a HIDA, what drugs can mimic biliary obstruction? (prompt uptake and delayed excretion)
dilantin/chlorpromazin and birth control
whats the deal with HIDAs in kids?
If there is tracer in the bowel, then its hepatitis
24hrs of delays because it can be slow
charge up hepatocytes with phenobarb
Kasai procedure
What lesion in the liver is hot on sulfur colloid?
FNH (30-40%of the time)
Which renal agent is used for determining GFR (filtration)?
Tc-DTPA
critical organ is the bladder
Which tracer is used to evaluate secretion/renal plasma flow?
Tc-MAG 3
critical organ is bladder
half life of thallium- 201?
energy?
73 hours
Energy is 2% low at 125, 8% at 167, use 71 201Hg daughter x-rays
Which agent is used for structural imaging?
Tc-GH (glucoheptonate)
Critical organ is bladder
What defines RAS on a captopril study?
10% or more worsening of renal function with addition of lasix
with DTPA sick kidney will have decreased uptake and flow because of loss of perfusion pressure
with MAG3 there will be marked tracer retention
Half life of indium-111?
energy?
67 hrs
“medium” 173 (89%) and 247 (94%)
Half life of gallium- 67?
energy?
78 hrs
multiple energies: 93 (40%), 184 (20%), 300 (20%), 393 (5%)
Which thyroid cancer is most avid for I-131 NaI?
Follicular
Y-90. what the deal is?
half life: 64 hrs / 2.7 days
Beta emitter
SIRspheres. what the deal is?
used for treatment of inoperable mets to liver. or HCC
same as therasphere. Y90 situation.
what are normal solid gastric emptying times?
@ 60 mins, 90% retention
@ 120 minutes, 60% retention
@240 minutes, 10% retention