Abstract：
PURPOSE:The quality of tomographic images is directly affected by the system model being used in image reconstruction. An accurate system matrix is desirable for high-resolution image reconstruction, but it often leads to high computation cost. In this work the authors present a maximum a posteriori reconstruction algorithm with residual correction to alleviate the tradeoff between the model accuracy and the computation efficiency in image reconstruction. METHODS:Unlike conventional iterative methods that assume that the system matrix is accurate, the proposed method reconstructs an image with a simplified system matrix and then removes the reconstruction artifacts through residual correction. Since the time-consuming forward and back projection operations using the accurate system matrix are not required in every iteration, image reconstruction time can be greatly reduced. RESULTS:The authors apply the new algorithm to high-resolution positron emission tomography reconstruction with an on-the-fly Monte Carlo (MC) based positron range model. Computer simulations show that the new method is an order of magnitude faster than the traditional MC-based method, whereas the visual quality and quantitative accuracy of the reconstructed images are much better than that obtained by using the simplified system matrix alone. CONCLUSIONS:The residual correction method can reconstruct high-resolution images and is computationally efficient.
journal_name
Med Physjournal_title
Medical physicsauthors
Fu L,Qi Jdoi
10.1118/1.3284980subject
Has Abstractpub_date
2010-02-01 00:00:00pages
704-13issue
2eissn
0094-2405issn
2473-4209journal_volume
37pub_type
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