title: Enhancement of SPECT images by Fourier filtering the projection image set.
abstract: Tomographic images from rotating gamma camera systems are often difficult to interpret because of poor contrast and high noise levels. A method is presented for improving the quality of these images by Fourier filtering the projection image set prior to reconstruction. A two-dimensional circularly symmetric Gaussian function is used as the spatial frequency filter. This filter can be optimized to enhance contrast and suppress noise in the projection image set in a straightforward and simple manner from the power spectra of representative projections. Preprocessing of the projections makes it possible to use a ramp reconstruction filter. The resulting tomographic sections show a dramatic improvement in image quality.
authors.forename: M T
authors.initials: MT
authors.lastname: Madsen
authors.forename: C H
authors.initials: CH
authors.lastname: Park
mesh_terms: D001842:Bone and Bones / Q000000981:diagnostic imaging; D001921:Brain / Q000000981:diagnostic imaging; D004164:Diphosphonates; D005374:Filtration / Q000295:instrumentation; D005583:Fourier Analysis; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation / Q000379:methods*; D007291:Inosine Monophosphate; D007457:Iodine Radioisotopes; D008905:Minicomputers; D013667:Technetium; D013669:Technetium Tc 99m Medronate; D014055:Tomography, Emission-Computed / Q000295:instrumentation / Q000379:methods*
chemical_list: D004164:Diphosphonates; D007457:Iodine Radioisotopes; D007291:Inosine Monophosphate; D013667:Technetium; D013669:Technetium Tc 99m Medronate