MRI-SPECT Multimodal Imaging

AbstraktAbstract

Common combination for clinical practice is CT with one of the scintigraphic methods (positron emission tomography (PET) or single photon emission computed tomography (SPECT)) nowadays. Multimodal imaging has become increasingly popular since MRI has started replacing CT in CT-PET combination. The demand for this combination is continuously growing and the methodology is highly developed. This allows to gain a high-structural resolution of soft tissues in MRI without depositing any radiation dose to the patient. Although MRI and SPECT are routine tools in medical imaging individually, the combination of these is still unexplored. By hybridizing high-resolution anatomical with functional imaging could be a valuable addition to the existing imaging methods, reducing overall scanning time and image co-registration errors. In contrast to PET, SPECT offers a cost-efficient range of applicable radioisotopes. A major disadvantage of mentioned systems is a presence of a high-magnetic field; therefore, all (ferro)magnetic materials have to be eliminated. Furthermore, the application of radiofrequency fields within the MR gantry does not allow using of conductive structures such as the common heavy metal collimators. Also there is an inability to operate scintillators with photomultipliers (used for detection of gamma rays). This chapter describes MRI-SPECT in detail and also presents hybrid semiconductor pixel detectors Timepix.

Common combination for clinical practice is CT with one of the scintigraphic methods (positron emission tomography (PET) or single photon emission computed tomography (SPECT)) nowadays. Multimodal imaging has become increasingly popular since MRI has started replacing CT in CT-PET combination. The demand for this combination is continuously growing and the methodology is highly developed. This allows to gain a high-structural resolution of soft tissues in MRI without depositing any radiation dose to the patient. Although MRI and SPECT are routine tools in medical imaging individually, the combination of these is still unexplored. By hybridizing high-resolution anatomical with functional imaging could be a valuable addition to the existing imaging methods, reducing overall scanning time and image co-registration errors. In contrast to PET, SPECT offers a cost-efficient range of applicable radioisotopes. A major disadvantage of mentioned systems is a presence of a high-magnetic field; therefore, all (ferro)magnetic materials have to be eliminated. Furthermore, the application of radiofrequency fields within the MR gantry does not allow using of conductive structures such as the common heavy metal collimators. Also there is an inability to operate scintillators with photomultipliers (used for detection of gamma rays). This chapter describes MRI-SPECT in detail and also presents hybrid semiconductor pixel detectors Timepix.