Abstract
State-of-the-art patient management frequently requires the use of non-invasive imaging methods to assess the anatomy, function or molecular-biological conditions of patients or study subjects. Such imaging methods can be singular, providing either anatomical or molecular information, or they can be combined, thus, providing “anato-metabolic” information. Hybrid imaging denotes image acquisitions on systems that physically combine complementary imaging modalities for an improved diagnostic accuracy and confidence as well as for increased patient comfort. The physical combination of formerly independent imaging modalities was driven by leading innovators in the field of clinical research and benefited from technological advances that permitted the operation of PET and MR in close physical proximity, for example. This review covers milestones of the development of various hybrid imaging systems for use in clinical practice and small-animal research. Special attention is given to technological advances that helped the adoption of hybrid imaging, as well as to introducing methodological concepts that benefit from the availability of complementary anatomical and biological information, such as new types of image reconstruction and data correction schemes. The ultimate goal of hybrid imaging is to provide useful, complementary and quantitative information during patient work-up. Hybrid imaging also opens the door to multi-parametric assessment of diseases, which will help us better understand the causes of various diseases that currently contribute to a large fraction of healthcare costs.
Highlights
Since the discovery of X-rays by Wilhelm Conrad Roentgen in 1895 [1], non-invasive medical imaging has become a standard tool for the diagnosis and staging of numerous diseases
In section Kinetic Modeling and Image Derived Input Function (IDIF) we discuss the use of image-derived input functions in the context of kinetic modeling, in section Multi-Parametric Imaging (MPI) we provide an overview of the multi-parametric imaging studies performed using SPECT/Computed Tomography (CT), Positron Emission Tomography (PET)/CT, and PET/Magnetic Resonance (MR) systems
Hybrid imaging is the physical combination of complementary anato-metabolic imaging modalities, and, to date, relates mainly to combined SPECT/CT, PET/CT, and PET/MR imaging, which are available for clinical use and small-animal research
Summary
Since the discovery of X-rays by Wilhelm Conrad Roentgen in 1895 [1], non-invasive medical imaging has become a standard tool for the diagnosis and staging of numerous diseases. Two facets of the design of the integrated CT components can be identified: first, SPECT/CT systems include fullydiagnostic CT systems with fast-rotation detectors that permit the simultaneous acquisition of 16 or 64 detector rows, while the X-ray tubes provide sufficient tube voltages together with high tube current and automatic exposure control (General Electric Discovery NM/CT 670 and the Siemens Symbia [32]). These systems support advanced CT capabilities such as cardiac gating, calcium scoring and iterative reconstruction [18, 33]. The two tomographs were situated next to each other with the patient table moving sideways between the Frontiers in Physics | www.frontiersin.org
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
