TY - GEN
T1 - 99mTc-MAA vs. 68Ga-MAA as perfusion agents
AU - Amor-Coarasa, Alejandro
AU - Milera, Andrew
AU - Carvajal, Denny A.
AU - McGoron, Anthony J.
PY - 2013
Y1 - 2013
N2 - The use of 99mTc Macroaggregated Albumin (MAA) as a perfusion agent has been evaluated since 1965. With the advent of Positron Emission Tomography (PET), an initial attempt to produce pharmaceutical grade 68Ga-MAA was successfully performed in 1989. However, a comparison of both perfusion agents, beyond the advantages of PET over Single Photon Emission Tomography (SPET) has not been performed to date. Both 99mTc-MAA and 68Ga-MAA were used to perform lung perfusion studies in male Sprague Dawley rats. Images were taken at several time points. Animals were euthanized at 2 and 4 hours, organs collected and biodistribution determined. Biodistribution of both agents was very similar within the first hour; however, 99mTc is released from the MAA after the first hour and it is excreted into the urine. 68Ga-MAA remains stable until 68Ga decays and more than 95% of the injected activity is concentrated in lungs. The previously reported 6 hour "in vivo" half-life of MAA is challenged. Both imaging agents are suitable for lung perfusion studies. However, the observed half-life of MAA, greater than 6 hours, has significant implication for other applications. 68Ga- MAA is introduced as a possible candidate for Selective Internal Radiation Treatment Planning agent.
AB - The use of 99mTc Macroaggregated Albumin (MAA) as a perfusion agent has been evaluated since 1965. With the advent of Positron Emission Tomography (PET), an initial attempt to produce pharmaceutical grade 68Ga-MAA was successfully performed in 1989. However, a comparison of both perfusion agents, beyond the advantages of PET over Single Photon Emission Tomography (SPET) has not been performed to date. Both 99mTc-MAA and 68Ga-MAA were used to perform lung perfusion studies in male Sprague Dawley rats. Images were taken at several time points. Animals were euthanized at 2 and 4 hours, organs collected and biodistribution determined. Biodistribution of both agents was very similar within the first hour; however, 99mTc is released from the MAA after the first hour and it is excreted into the urine. 68Ga-MAA remains stable until 68Ga decays and more than 95% of the injected activity is concentrated in lungs. The previously reported 6 hour "in vivo" half-life of MAA is challenged. Both imaging agents are suitable for lung perfusion studies. However, the observed half-life of MAA, greater than 6 hours, has significant implication for other applications. 68Ga- MAA is introduced as a possible candidate for Selective Internal Radiation Treatment Planning agent.
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U2 - 10.1109/SBEC.2013.74
DO - 10.1109/SBEC.2013.74
M3 - Conference contribution
AN - SCOPUS:84880854802
SN - 9780769550329
T3 - Proceedings - 29th Southern Biomedical Engineering Conference, SBEC 2013
SP - 131
EP - 132
BT - Proceedings - 29th Southern Biomedical Engineering Conference, SBEC 2013
T2 - 29th Southern Biomedical Engineering Conference, SBEC 2013
Y2 - 3 May 2013 through 5 May 2013
ER -