Abstract：
:As a potentially important technology for medical x-ray computed tomography (CT), lambda tomography (LT) is to reconstruct a gradient-like image only from local projection data. Based on our recently derived exact fan-beam LT formula, [H. Y. Gu and G. Wang, Int. J. Biomed. Imaging 2006(1), 1-9 (2006)] here we propose a practical cone-beam LT algorithm for LT reconstruction from local data collected along an arbitrary smooth three-dimensional curve. A key step in our algorithm is to determine an appropriate vector perpendicular to the line connecting the x-ray source and an image point. The algorithm is implemented assuming an equispatial planar detector and a nonstandard spiral trajectory. The numerical simulation results demonstrate the merits of our method.
journal_name
Med Physjournal_title
Medical physicsauthors
Yu H,Ye Y,Wang Gdoi
10.1118/1.2348767subject
Has Abstractpub_date
2006-10-01 00:00:00pages
3640-6issue
10eissn
0094-2405issn
2473-4209journal_volume
33pub_type
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