The Optimization of the Single Photon Emission Computed Tomography Image Quality via Taguchi Analysis: A Feasibility Study of a V -Shaped Phantom

A feasibility study was undertaken to evaluate the spatial resolution for Single Photon Emission Computed Tomography (SPECT) images from a gamma camera using Taguchi analysis through a V-shaped phantom. Spatial resolution was a major characteristic for the SPECT and it was affected by a number of factors. The spatial resolution of SPECT was analyzed through a revised t-test through practical measurement. The Siemens's E-cam SPECT system Wand V-shaped line sources phantom were used to acquire practical images. A total of eighteen combinations of five factors were arranged according to Taguchi's recommendation. The five factors used in this study were scan mode, collimator type, matrix size, zoom, and frame time. The S/N (eta) ratio was defined to fulfill the requirements of optimized spatial resolution of the SPECT image acquisition in a variety of various combinations. A statistical analysis of variance (ANOVA) was used to determine the significant factors. The optimized values were focused to be continuous scan mode, LEHR collimator, 256 x 256 Matrix size, zoom set as 1.45, and frame time for 30 sec. Practical verification led to the reduction of the optimized spatial resolution to 14.23 mm from the original 17.71 mm. The effectiveness from the L-18 orthogonal array helped significantly in reducing the multiple measurements in practical survey.