ImSim: A nuclear imaging teaching simulator using compiled MATLAB

Purpose: Learning Objectives: To demonstrate the value of a purpose-built nuclear imaging simulator in nuclear medicine education. Summary: Nuclear medicine imaging physics involves many mathematically sophisticated concepts that are often difficult for technologist students to learn and apply. Student are required to understand planar projection imaging, sinograms, tomographic reconstruction, digital filtering, image quality and much more with neither the background nor the time to master the mathematical formalisms. Nevertheless, these concepts are used in selecting acquisition and processing parameters for optimal clinical imaging. For many years I have developed and used computer tutorials using MathCAD® (PTC) to demonstrate and explore nuclear imaging principles without mathematical details (J Nucl Med May 2009 vol. 50 no. supplement 2 801). These tutorials were very well received, but due to limitations in functionality, ease of use and deployment, the tutorials were limited to classroom demonstrations. I have recently begun developing a nuclear imaging teaching simulator (ImSim) using MATLAB® (Mathworks). MATLAB scripts may be compiled to create distributable applications. MATLAB also has greatly increased functionality allowing for more complex simulation capability. ImSim simulates planar and SPECT imaging in real or accelerated time. The user chooses whether to include the effects of attenuation, image noise and/or depth-dependent blurring. The user may select from a wide range of digital phantoms, from simple geometric shapes, standard planar and SPECT phantoms to a digital anthropomorphic phantom for simulating different types of clinical imaging. ImSim allows users to choose different acquisition parameters including camera and collimator type, detector distance and orientation, acquisition matrix, imaging time/counts, SPECT dual detector orientation, number of gantry stops and much more. Reconstruction choices include reconstruction method (FBP, OSEM) and parameters (filtering parameters, number of iterations and subsets). Image analysis may be done to view profiles, calculate contrast, noise, uniformity and more. Simulation of detector calibrations (tuning, linearity, energy and flood corrections) and of PET and CT imaging are at various stages of development. ImSim is used at BCIT for classroom demos and beginning to be used for independent and group homework assignments. Through ImSim students gain the necessary insights to relate imaging parameters to the resulting image quality.