Abstract:
:We explore how the radioactive background from naturally occurring 176Lu affects single photon transmission imaging for lutetium orthosilicate (LSO) scintillator-based PET cameras by estimating the transmission noise equivalent count rate (NECR) including this background. Assuming a typical PET camera geometry (80 cm detector ring diameter), we use a combination of measurement and analytic computation to estimate the counting rates due to transmission, scatter and background events as a function of singles transmission source strength. We then compute a NECR for singles transmission. We find that the presence of radiation from the naturally occurring 176Lu reduces the NECR by 60% or higher for source strengths less than 10 mCi, and that a 25% reduction of the NECR can occur even with a source strength of 40 mCi.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Huber JS,Moses WW,Jones WF,Watson CCdoi
10.1088/0031-9155/47/19/307subject
Has Abstractpub_date
2002-10-07 00:00:00pages
3535-41issue
19eissn
0031-9155issn
1361-6560journal_volume
47pub_type
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