title: Vision 20/20: Simultaneous CT-MRI--Next chapter of multimodality imaging.
abstract: Multimodality imaging systems such as positron emission tomography-computed tomography (PET-CT) and MRI-PET are widely available, but a simultaneous CT-MRI instrument has not been developed. Synergies between independent modalities, e.g., CT, MRI, and PET/SPECT can be realized with image registration, but such postprocessing suffers from registration errors that can be avoided with synchronized data acquisition. The clinical potential of simultaneous CT-MRI is significant, especially in cardiovascular and oncologic applications where studies of the vulnerable plaque, response to cancer therapy, and kinetic and dynamic mechanisms of targeted agents are limited by current imaging technologies. The rationale, feasibility, and realization of simultaneous CT-MRI are described in this perspective paper. The enabling technologies include interior tomography, unique gantry designs, open magnet and RF sequences, and source and detector adaptation. Based on the experience with PET-CT, PET-MRI, and MRI-LINAC instrumentation where hardware innovation and performance optimization were instrumental to construct commercial systems, the authors provide top-level concepts for simultaneous CT-MRI to meet clinical requirements and new challenges. Simultaneous CT-MRI fills a major gap of modality coupling and represents a key step toward the so-called "omnitomography" defined as the integration of all relevant imaging modalities for systems biology and precision medicine.
authors.affiliation: Biomedical Imaging Center/Cluster, Rensselaer Polytechnic Institute, Troy, New York 12180.
authors.forename: Ge
authors.initials: G
authors.lastname: Wang
authors.affiliation: Department of Imaging, Massachusetts General Hospital, 55 Fruit Street, Boston, Massachusetts 02114.
authors.forename: Mannudeep
authors.initials: M
authors.lastname: Kalra
authors.affiliation: Department of Imaging, Massachusetts General Hospital, 55 Fruit Street, Boston, Massachusetts 02114.
authors.forename: Venkatesh
authors.initials: V
authors.lastname: Murugan
authors.affiliation: Biomedical Imaging Center/Cluster, Rensselaer Polytechnic Institute, Troy, New York 12180.
authors.forename: Yan
authors.initials: Y
authors.lastname: Xi
authors.affiliation: Biomedical Imaging Center/Cluster, Rensselaer Polytechnic Institute, Troy, New York 12180.
authors.forename: Lars
authors.initials: L
authors.lastname: Gjesteby
authors.affiliation: Biomedical Imaging Center/Cluster, Rensselaer Polytechnic Institute, Troy, New York 12180.
authors.forename: Matthew
authors.initials: M
authors.lastname: Getzin
authors.affiliation: Biomedical Imaging Center/Cluster, Rensselaer Polytechnic Institute, Troy, New York 12180.
authors.forename: Qingsong
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Biomedical Imaging Center/Cluster, Rensselaer Polytechnic Institute, Troy, New York 12180.
authors.forename: Wenxiang
authors.initials: W
authors.lastname: Cong
authors.affiliation: Department of Radiology, University of Chicago, Chicago, Illinois 60637.
authors.forename: Michael
authors.initials: M
authors.lastname: Vannier
mesh_terms: D005240:Feasibility Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D064847:Multimodal Imaging / Q000295:instrumentation / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*