| Autor: |
Celeste Winant, Arkadiusz Sitek, Yuval R. Zelnik, Grant T. Gullberg, S.L. Bacharach, Carina Mari Aparici, Bryan W. Reutter |
| Rok vydání: |
2009 |
| Předmět: |
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| Zdroj: |
2009 IEEE Nuclear Science Symposium Conference Record (NSS/MIC). |
| DOI: |
10.1109/nssmic.2009.5401769 |
| Popis: |
Measurement of the arterial input function (AIF) is essential to deriving quantitative estimates of regional myocardial blood flow using kinetic models. Accurate measurements have been possible with a wide range of radiotracers in both research and clinical PET/CT imaging. However, accurate measurements of the AIF with dynamic SPECT or SPECT/CT have posed various challenges; foremost being that imaging a rapidly evolving radiotracer distribution with a slowly-rotating single- or dual-head SPECT scanner yields temporally inconsistent projection data. A method is developed for quantifying the AIF in human subjects from dynamic SPECT/CT measurements of 99mTc-tetrofosmin concentration in the left atrium imaged with a Philips Precedence SPECT/CT scanner. A 2-minute infusion is imaged in a series of eight back-to-back 180-degree continuous-mode acquisitions (or rotations), with the dual camera heads. In each acquisition a set of 36 projections (128 × 128 pixels of dimension 3.19 mm × 3.19 mm) is acquired in each rotation each over a time span of 54 seconds yielding a total acquisition time of 432 seconds. The AIF is computed using both traditional image-based analysis and full spatiotemporal image reconstruction methods (referred to as 4D recon). The errors induced by data inconsistency are evaluated by two approaches. The first method derives SPECT-like dynamic (inconsistent) projection data from selected forward projections, chosen from modeled SPECT acquisitions, of existing dynamic 94Tc-MIBI PET images. The second validation method uses a database of SPECT measurements of an anthropomorphic phantom to generate SPECT-like projections. The first validation study using a two minute infusion showed very little bias in the time-activity curves estimated from the simulated dynamic cardiac SPECT patient study; whereas, the second validation study using a one minute infusion showed considerable more bias in the estimated time-activity curves and parametric parameters. We believe that this is the result of selecting non optimum basis functions. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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