title: Magnetic resonance imaging methodology.
abstract: BACKGROUND
  Magnetic resonance (MR) methods are non-invasive techniques to provide detailed, multi-parametric information on human anatomy, function and metabolism. Sensitivity, specificity, spatial and temporal resolution may, however, vary depending on hardware (e.g., field strength, gradient strength and speed) and software (optimised measurement protocols and parameters for the various techniques). Furthermore, multi-modality imaging may enhance specificity to better characterise complex disease patterns.
  
  
  OBJECTIVE
  Positron emission tomography (PET) is an interesting, largely complementary modality, which might be combined with MR. Despite obvious advantages, combining these rather different physical methods may also pose challenging problems. At this early stage, it seems that PET quality may be preserved in the magnetic field and, if an adequate detector material is used for the PET, MR sensitivity should not be significantly degraded. Again, this may vary for the different MR techniques, whereby functional and metabolic MR is more susceptible than standard anatomical imaging.
  
  
  CONCLUSIONS
  Here we provide a short introduction to MR basics and MR techniques, also discussing advantages, artefacts and problems when MR hardware and PET detectors are combined. In addition to references for more detailed descriptions of MR fundamentals and applications, we provide an early outlook on this novel and exciting multi-modality approach to PET/MR.
authors.affiliation: MR Center of Excellence, Medical University of Vienna, Lazarettgasse 14, 1090, Vienna, Austria. Ewald.Moser@meduniwien.ac.at
authors.forename: Ewald
authors.initials: E
authors.lastname: Moser
authors.forename: Andreas
authors.initials: A
authors.lastname: Stadlbauer
authors.forename: Christian
authors.initials: C
authors.lastname: Windischberger
authors.forename: Harald H
authors.initials: HH
authors.lastname: Quick
authors.forename: Mark E
authors.initials: ME
authors.lastname: Ladd
mesh_terms: D016477:Artifacts; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D049268:Positron-Emission Tomography; D013997:Time Factors