Breast phantom enhancement: Taguchi-type optimization for CT scan imaging quality and additive manufacturing realization

Abstract

An indigenous breast phantom was customized to optimize the imaging quality of the CT scan according to Taguchi's methodology. A 3D printer made the base gauge of the breast phantom, and the polysmooth^TM filament was sprayed. The gauge can be categorized into three major parts vertical and horizontal line pairs, two V-shape slices, and two arrays of nodules with various sizes, then a spherical shell mad by paraffin casting and the sunflower oil was infused as filling material. The Taguchi approach led to the development of a customized measuring device that enabled quantitative assessment aimed at improving the spatial resolution of CT image quality. Five essential factors for operating the CT chest scan (kVp, mAs, FOV, Pitch, and gantry rotation time) were organized according to Taguchi L₁₈(2¹ × 3⁴) suggestion. Three well-trained radiologists ranked the imaging quality in three discrete time periods according to the imaging quality's sharpness, contrast, and spatial resolution. The derived average, standard deviation, and signal-to-noise ratio of specific factors were reorganized and analyzed from the multiple measurements to propose the optimal CT chest scan protocol recommendation. Accordingly, the optimal suggestion was A1(120 kVp), B3(200 mAs), C2(FOV 350 mm²), D1(pitch 0.516) and E2(rotation time 0.75 s) to fulfill the ALARA principle. In this research, a numerical metric termed the minimum detectable difference (MDD) was introduced to evaluate imaging performance, and its calculated value demonstrated a resolution capability of approximately 1.57 mm.