Lung #1
______ is a particulate radiopharmaceutical used for lung perfusion studies.
MAA
True or False. A nebulizer should be used for ventilation studies involving Xe-133.
False.
Why should we use a large bore needle when transferring blood samples into an ultratag kit?
To prevent RBC lysis
which type of RBC labeling procedure is Ultratag used for? (choices: In Vitro, In Vivo, modified In Vivo)
In Vitro
A pharmacist prepares an MAA kit containing 6x106 particles with 100 mCi in 5 mL at 6:00. How many particles per mL does this kit contain at 12:00?
1,200,000 particles per mL. (remember particles per mL doesn't change with time)
The tiny sacs in the lungs where gas exchange occurs is the __________
alveoli
True or false. Most MAA particles are in the range of 100-900 um.
False. 10-90 um.
True or False. You should not inject PYP and NaTcO4 (Tc99M) at the same time when tagging RBCs in vivo.
True
What is the purpose of syringe I in an Ultratag kit?
oxidizes extracellular stannous ion
If an MAA kit containing 2.5 million particles is prepared by adding 50 mCi in a volume of 6.5 ml, how many particles are contained in 3 mCi? (assume we are pulling 3 mCi at the time we make the kit – no decay has occurred)
150,000
________ is a radioactive gas and DTPA is a radioaerosol used for lung ventilation studies.
Xe-133
What is the danger of having MAA particles that are larger than 150 um?
occlusion of blood flow in the lungs (pulmonary embolism)
Name two studies that tagged RBCs can be used for
GI bleed, MUGA study, Ejection Fraction
What is the agent of choice for intermittant gastrointestinal bleeding?
Tagged RBCs (Ultratag)
An MAA kit containing 3 million particles is prepared with 80 mCi in 4 mL at 06:00. How many particles will a 5 mCi dose at 10:00 contain?
approximately 297,000 particles
Besides lung studies, what is one other study that can be performed with DTPA?
Brain imaging, GFR, kidney imaging
According to the MAA package insert, what is the range of particles allowed in a normal patient (not a reduced particle dose)?
200,000 to 700,000
True or False. During In vivo tagging of RBCs, Tc99m-PYP is injected into the patient to tin the RBCs.
False. PYP that is injected for in vivo labeling of RBCs in not radioactive. PYP is reconstituted with NaCl prior to injection. Here at Vanderbilt, we used Tc99m labeled PYP for myocardial plaque imaging. It was also used as a bone imaging agent in the past.
What is the effect of stannous ion on Tc99m
stannous ion reduces Tc99m
If a unit dosage of Tc99m MAA contains 4 mCi and 625,000 particles in 0.9 ml at 1000, approximately how many particles will be contained in 4 mCi at 1600? (half life of Tc99m = 6 hrs)
aproximately 1,250,000 particles
What is one contraindication of MAA lung studies?
Hypersensitivity to albumin or SEVERE pulmonary hypertension
What is the range of particles for a reduced particle MAA dose?
100,000 to 250,000
What is the difference between the in vivo and modified in vivo methods of labeling RBCs?
In both methods, RBCs are tinned within the patient using PYP. In the in vivo method, Tc99m is then introduced to the RBCs within the patient. In the modified in vivo method, the Tc99m is introduced to the RBCs outside of the patient's body and then reinjected.
What is the recommended amount of heparin to be used when preparing the blood sample for Ultratag?
10-15 units heparin per milliliter of blood
If a syringe of Tc99m MAA contains 5 mCi and 400,000 particles in 0.6 ml at 1200, approximately how many particles will be contained in 5 mCi at 1000? (half life of Tc99m = 6 hrs)
Aproximately 317,500 particles