title: GPU-based prompt gamma ray imaging from boron neutron capture therapy.
abstract: OBJECTIVE
  The purpose of this research is to perform the fast reconstruction of a prompt gamma ray image using a graphics processing unit (GPU) computation from boron neutron capture therapy (BNCT) simulations.
  
  
  METHODS
  To evaluate the accuracy of the reconstructed image, a phantom including four boron uptake regions (BURs) was used in the simulation. After the Monte Carlo simulation of the BNCT, the modified ordered subset expectation maximization reconstruction algorithm using the GPU computation was used to reconstruct the images with fewer projections. The computation times for image reconstruction were compared between the GPU and the central processing unit (CPU). Also, the accuracy of the reconstructed image was evaluated by a receiver operating characteristic (ROC) curve analysis.
  
  
  RESULTS
  The image reconstruction time using the GPU was 196 times faster than the conventional reconstruction time using the CPU. For the four BURs, the area under curve values from the ROC curve were 0.6726 (A-region), 0.6890 (B-region), 0.7384 (C-region), and 0.8009 (D-region).
  
  
  CONCLUSIONS
  The tomographic image using the prompt gamma ray event from the BNCT simulation was acquired using the GPU computation in order to perform a fast reconstruction during treatment. The authors verified the feasibility of the prompt gamma ray image reconstruction using the GPU computation for BNCT simulations.
authors.affiliation: Department of Biomedical Engineering and Research Institute of Biomedical Engineering, College of Medicine, Catholic University of Korea, Seoul 505 137-701, Korea.
authors.forename: Do-Kun
authors.initials: DK
authors.lastname: Yoon
authors.affiliation: Department of Biomedical Engineering and Research Institute of Biomedical Engineering, College of Medicine, Catholic University of Korea, Seoul 505 137-701, Korea.
authors.forename: Joo-Young
authors.initials: JY
authors.lastname: Jung
authors.affiliation: Molecular Imaging Program at Stanford (MIPS), Department of Radiology, Stanford University, 300 Pasteur Drive, Stanford, California 94305.
authors.forename: Key
authors.initials: K
authors.lastname: Jo Hong
authors.affiliation: Department of Radiation Oncology, Stanford University School of Medicine, 875 Blake Wilbur Drive, Stanford, California 94305-5847.
authors.forename: Keum
authors.initials: K
authors.lastname: Sil Lee
authors.affiliation: Department of Biomedical Engineering and Research Institute of Biomedical Engineering, College of Medicine, Catholic University of Korea, Seoul 505 137-701, Korea.
authors.forename: Tae
authors.initials: T
authors.lastname: Suk Suh
mesh_terms: D000465:Algorithms; D016754:Boron Neutron Capture Therapy; D003196:Computer Graphics; D005720:Gamma Rays / Q000627:therapeutic use*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D047368:Tumor Burden / Q000528:radiation effects