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Updated: Jan 31, 2026

Neutron Radiography and Computed Tomography of Biological Systems at the Oak Ridge National Laboratory's High Flux Isotope Reactor
Published on: May 7, 2021
[Improvement of the Radiographic Contrast in Off-center Radiography with Focused Grid]
1Wakamatsu Hospital of the University of Occupational and Environmental Health (Current address: Kitakyusyu Tsuyazaki Hospital).
Abstract:
In radiography with focused grid, it is important to agree the X-ray center on the grid center. Actually, radiography is often put the off-center alignment which disagrees the X-ray center to the grid center. This misalignment decreases radiographic contrast because of cutoff the primary X-rays. The grid-tilt technique which makes the grid tilt corresponding to the misalignment of the X-ray center and the grid center was investigated. Using solid state dosimeter and 10 cm water phantom, transited dose of focused grids (focal distance 120 cm, grid ratio 6:1 and 8:1) were measured at off-center. The transited dose at 6 cm off-center by conventional manner was lower 20% (6:1) and 30% (8:1) to center's one. While by grid-tilt technique, the transited dose at off-center was same to the center's one. Axial radiography of hip joint was applied by this technique.
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