A. Ersahin et al., A DIGITAL FILTRATION TECHNIQUE FOR SCATTER-GLARE CORRECTION BASED ON THICKNESS ESTIMATION, IEEE transactions on medical imaging, 14(3), 1995, pp. 587-595
Citations number
21
Categorie Soggetti
Engineering, Biomedical","Radiology,Nuclear Medicine & Medical Imaging
In order to quantitate anatomical and physiological parameters such as
vessel dimensions and volumetric blood dow, it is necessary to make c
orrections for scatter and veiling glare, which are the major sources
of nonlinearities in videodensitometric digital subtraction angiograph
y (DSA), A convolution filtering technique has been investigated to es
timate scatter-glare distribution in DSA images without the need to sa
mple the scatter-glare intensity for each patient, This technique util
izes exposure parameters and image gray levels to assign equivalent Lu
cite thickness for every pixel in the image, The thickness information
is then used to estimate scatter-glare intensity on a pixel-by-pixel
basis, To test its ability to estimate scatter-glare intensity, the co
rrection technique was applied to images of a Lucite step phantom, ant
hropomorphic chest phantom, head phantom, and animal models at differe
nt thicknesses, projections, and beam energies, The root-mean-square (
rms) percentage error of these estimates was obtained by comparison wi
th direct scatter-glare measurements made behind a lead strip, The ave
rage rms percentage errors in the scatter glare estimate for the 25 ph
antom studies and the 17 animal studies were 6.44% and 7.96%, respecti
vely, These results indicate that the scatter-glare intensity can be e
stimated with adequate accuracy for a wide range of thicknesses, proje
ctions, and beam energies using exposure parameters and gray level inf
ormation.