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14 Cards in this Set
- Front
- Back
- 3rd side (hint)
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What is the principle RP used for tumor imaging?
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Ga-67 citrate
what is the usual dose? half life? 4 principle gamma peaks? |
6-10 mCi
78.2 hrs 93.3 - 40% 184.6 - 24% 296.0 - 22% 388.0 - 7% |
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What is the method of localization for Ga-67 on tumors?
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In inflammatory processes lactoferrin is released by WBC's which Ga-67 binds to. In tumors Ga-67 appears to bind to intercellular components, not clear how it happens, just know it works
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What are some factors that may interfere with Ga-67 uptake?
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1. chemotherapy - duffuse lung uptake
2. radiation therapy-decreased uptake 3. antibiotics - increase in colon and kidney uptake 4. Estrogen - increase in mammary tissue uptake |
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What is the imaging time for Ga-67 scans?
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6 hours post injection to 1 week
What are 2 important factors in later imaging times (past 2 days) |
1. improved sensitivity due to increased target-to-background ratio
2. low count rate makes for longer imaging times |
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The majority of gallium clears from the blood in ________, _____of it remains in the body, effective half life is ____ hours, within 24 hrs ______is excreted in the urine and ____ excreted in the stool
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The majority of gallium clears from the blood in 3 hours, 65% of it remains in the body, effective half life is 69.5 hours, within 24 hrs 10-15% is excreted in the urine and 10% excreted in the stool
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Indications for Gallium scan?
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Hodgkins Lymphoma, lumphoma, bronchogenic and hepatocellular carcinoma, melanoma, inflammatory processes like cellulitis,osteomyelitis, lung conditions and FUO (fever of unknown origin)
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CFILL
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What is sarcoidosis?
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a disease in which abnormal collections of inflammatory cells called granulomas form in many organs of the body but frequently in the lungs, unknown cause
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In111 for labeling WBC's uses what dose, what is the half life and energy level?
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0.5 mCi
67.2 hrs 171.3 keV |
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When do you scan post injection for In111 and how is it localized?
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taken up through chemotaxis of wbc's
scan 3-4 hrs and again 24 hrs |
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When is a In111 WBC scan indicated?
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confirmation of an acute abscess or inflammation when ultrasound, MRI and CT findings are negative or ambiguous
why is gallium better for chronic conditions of this nature? |
In111 decreases with time
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which RP is better for inflammatory bowel disease?
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In111 as gallium is excreted through the colon which obscures or confuses abdominal images
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Which type of leukocyte has a high affinity for acute abscesses, infection and inflammation and kill microorganisms by phagocytosis and make up the majority (60%) of WBC's?
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neutrophils
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Why is Tc not used often even though is offers a higher count rate, offers easier availability and lower cost?
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shorter half life, 24 hr imaging difficult
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MAA is trapped in the lung arterioles and capillaries since their particle size is _______ and the vessel diameter is about _____. About _______ arterioles will occlude(less than ___) with ___ to ____ particles, cleared from lungs in _____
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MAA is trapped in the lung arterioles and capillaries since their particle size is 30-40 um and the vessel diameter is about 8 um. About 1/1000 arterioles will occlude(less than 1%) with 100 to 500k particles, cleared from lungs in 2-3 hrs
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