Introduction:Low-pass filters eliminate noise, and accordingly improve the quality of filtered back-projection (FBP) in the reconstruction of single photon emission computed tomography (SPECT) images. This study aimed at selection of an optimum low-pass filter for FBP reconstruction of SPECT images of small structures. Material and Methods:Sp...

Introduction: One of the major problems in the development of nuclear medicine images is the presence of noise. The noise level in nuclear medicine images is usually reduced by the analysis of imaging data in a Fourier transform environment. The main drawback of this environment belongs to low signal to noise ratio in high frequencies because removing noise frequencies may remove data and times...

Objective: Reconstruction parameters must be optimized to approach the improved spatial resolution that is theoretically possible from modern SPECT imaging devices. One important reconstruction consideration is proper selection of the back-projection filter parameters. The aim of this study was to determine which Butterworth filter optimized image resolution for brain SPECT scans. Methods: Ten ...

Infinite Impulse Response (IIR) filter is of recursive type filter. The present output sample of an IIR filter depends on the present input samples, past input samples and past output samples. There are a number of techniques available to determine the digital IIR Filters. This paper is based on the computer based approach to design the digital IIR filter along with the calculation of filter co...

a fundamental aspect of signal processing is filtering. Filtering involves the manipulation of the spectrum of a signal by passing or blocking certain portions of the spectrum, depending on the frequency of those portions. In this paper, Digital filters are designed using frequency specifications. Matlab provides different options for digital filter design, which includes function, calls to fil...