Relationship between sharpness and noise in CT images reconstructed with different kernels.
The sharpness expressed as the full-width at half-maximum of the line spread function (LSF) was derived for different CT scanners and reconstruction kernels. The LSFs were calculated from images of a 0.28 mm tungsten bead and successfully fitted to cumulative Gaussians by means of probit plots. The corresponding image noise was measured in a homogeneous material. The investigation showed that the noise increases strongly for small improvements in sharpness. The method was reproducible and insensitive to small positional shifts of the phantom.
Eldevik
K
K
The Interventional Centre, Oslo University Hospital, Oslo, Norway.
Nordhøy
W
W
Skretting
A
A
D000465:Algorithms; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000379:methods*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*