Abstract
We have developed an uncollimated sheet line source with a fluoroplastic tube for gamma ray transmission CT (TCT). This source filled with Tc-99m was attached to the collimator face on one head of a dual head single photon emission computed tomography (SPECT) system. In simultaneous SPECT/TCT scans using Tl-201 as the SPECT source and Tc-99m as the TCT source, scatter and spilldown contamination in the Tc-99m (141 keV) data and the Tl-201 (75 keV) data can be removed with the triple energy window (TEW) method. However, lead X-ray contamination in the Tl-201 data cannot be removed with the TEW method. We have developed an estimation method of the lead X-ray contamination in the Tl-201 data. This method depends on the hypothesis that the lead X-ray is proportional to the amount of attenuating media and primary photons along each projection path. The amount of attenuating media is given by a transmission image and that of primary photons is estimated by the TEW method. The coefficients needed for this estimation are experimentally determined by only Tc-99m TCT scan data. The feasibility of the proposed method was demonstrated by a chest phantom study and a myocardial clinical study.
Original language | English |
---|---|
Pages (from-to) | 2459-2464 |
Number of pages | 6 |
Journal | IEEE Transactions on Nuclear Science |
Volume | 44 |
Issue number | 6 PART 2 |
DOIs | |
Publication status | Published - 1997 |
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics
- Nuclear Energy and Engineering
- Electrical and Electronic Engineering