Tomography, X-Ray ComputedTomography, Emission-Computed, Single-PhotonTomographyPositron-Emission TomographyOrganotechnetium CompoundsTomography, Emission-ComputedTomography, Optical CoherenceTechnetium Tc 99m ExametazimeOximesRadiopharmaceuticalsTomography, Spiral ComputedTechnetium Tc 99m SestamibiTomography, OpticalGamma RaysMultidetector Computed TomographyRadiographyThallium RadioisotopesSensitivity and SpecificityCone-Beam Computed TomographyElectron Microscope TomographyImage Processing, Computer-AssistedPhantoms, ImagingIodine RadioisotopesFluorodeoxyglucose F18Reproducibility of ResultsIofetamineTomography, X-RayGated Blood-Pool ImagingMagnetic Resonance ImagingElectron Probe MicroanalysisImaging, Three-DimensionalBrainTechnetiumTomography Scanners, X-Ray ComputedTropanesCerebrovascular CirculationRadiation DosageGamma CamerasPneumoconiosisElasmobranchiiCardiac-Gated Single-Photon Emission Computer-Assisted TomographySkates (Fish)Myocardial Perfusion ImagingMultimodal ImagingFluorine RadioisotopesIodobenzenesImage EnhancementPredictive Value of TestsThalliumHeartProspective StudiesFast NeutronsArtifactsSubtraction TechniqueRadiology Department, HospitalRetrospective StudiesOrganophosphorus CompoundsTime FactorsAmphetaminesRadiometryAlgorithmsTechnetium Tc 99m MedronateWrist JointFollow-Up StudiesDose-Response Relationship, RadiationRadiation EffectsUltraviolet RaysDiagnostic ImagingLungRadiographic Image Interpretation, Computer-AssistedX-Ray MicrotomographyTeleradiologyCraniocerebral TraumaContrast MediaSpectrometry, X-Ray EmissionSodium Pertechnetate Tc 99mNortropanesMetacarpophalangeal JointAluminum SilicatesAnimal FinsMetacarpusCoronary AngiographyTechnetium Tc 99m Aggregated AlbuminXenon RadioisotopesObserver VariationExercise TestCoronary Artery DiseaseDiagnostic ErrorsSeverity of Illness IndexX ChromosomeCathode Ray TubePleuraGallium RadioisotopesImage Interpretation, Computer-AssistedFlumazenilEquipment DesignAsbestosisModels, StructuralTreatment OutcomeEmergency Service, Hospital