Transition to GPU-based reconstruction for clinical organ-targeted PET scanner

<i>Objective.</i>This article explores a new graphics processing unit (GPU)-based techniques for efficient image reconstruction in organ-targeted positron emission tomography (PET) scanners with planar detectors.<i>Approach.</i>GPU-based reconstruction is applied to the Radialis low-dose organ-targeted PET technology, developed to overcome the issues of high exposure and limited spatial resolution inherent in traditional whole-body PET/CT (Computed Tomography) scans. The Radialis planar detector technology is based on four-side tileable sensor modules that can be seamlessly combined into a sensing area of the needed size, optimizing the axial field-of-view for specific organs, and maximizing geometric sensitivity. The article explores the transition from central processing unit-based maximum likelihood expectation maximization algorithms to a GPU-based counterpart, demonstrating a tenfold overall speedup in image reconstruction with a hundredfold improvement in iteration speed.<i>Main results.</i>Through standardized PET performance tests and clinical image analysis, this work demonstrates that GPU-based image reconstruction maintains diagnostic image quality while significantly reducing reconstruction times. The application of this technology, particularly in breast imaging using the Radialis low-dose positron emission mammography, significantly reduces exam times thus improving patient comfort and throughput in clinical settings.<i>Significance.</i>This study represents an important advancement in the clinical workflow of PET imaging, providing insights into optimizing reconstruction algorithms to effectively leverage the parallel processing capabilities of GPUs.