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An extension to artifact-free projection overlaps.
1Department of Electrical and Computer Engineering, Curtin University, GPO Box U1987, Perth, Western Australia 6845, Australia.
Medical Physics
|May 17, 2015
Summary
This study extends artifact-free projection overlaps for multipinhole SPECT imaging, enabling artifact-free designs for baffle window systems to improve sensitivity in imaging long objects.
Area of Science:
- Medical Imaging
- Nuclear Medicine
- Image Reconstruction
Background:
- Multipinhole single photon emission computed tomography (SPECT) uses projection overlaps to enhance sensitivity.
- Avoiding artifacts in reconstructed images due to projection overlaps (multiplexing) is crucial for accurate SPECT imaging.
Purpose of the Study:
- To introduce a new proposition extending type-II artifact-free projection overlaps for multipinhole SPECT.
- To accommodate a broader range of artifact-free overlaps, including those with minor reconstruction inaccuracies.
- To apply this extension in designing baffle window multipinhole systems with artifact-free projection overlaps.
Main Methods:
- Theoretically defined and proved extended type-II artifact-free overlaps.
- Designed multiplexing multipinhole spiral orbit imaging systems with a baffle window using the extended overlaps.
- Validated the theory through simulations comparing artifact-free multiplexing systems with 1-pinhole nonmultiplexing benchmarks using Mean Square Error (MSE).
Main Results:
- Noise-free reconstructions showed Mean Square Errors (MSEs) for artifact-free multiplexing systems comparable to 1-pinhole systems.
- No artifacts were observed in the reconstructed images from the designed systems.
- Simulation results numerically validated the developed theory for artifact-free multiplexing systems.
Conclusions:
- The extension theoretically broadens options for optimizing multiplexing multipinhole SPECT designs.
- The extension enables practical application in designing artifact-free baffle window multipinhole systems with spiral orbits.
- This artifact-free design allows sensitive imaging of specific axial portions of long objects via projection overlaps.
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