医学影像原理介绍

醫學影像原理介紹History1895:WilliamK.RoentgendiscoveredX-rays.1901~1930:intensifyingscreen,tomography,andtherotatinganodetube.~1970:nuclearmedicine.ultrasound,CT,~1980:PET,MRI,Microwave.~future:multi-modalityimagesystem,PACS放射醫學影像介紹何謂醫學影像醫學影像種類傳統X光影像特殊攝影影像電腦斷層影像核磁共振斷層影像核子醫學造影影像其他影像醫學影像資訊結構性影像資訊CT,MRI,X-ray,Ultrasound功能性影像資訊Functional-MRI,NuclearMedicine融合影像資訊CT-SPECT,MRI-SPECTCT-PET,MRI-PETCT-MRICameraprincipleMEDICALIMAGEEQUIPMENTEMWAVESPECTRUMImageSignalTransmissionEmissionMagneticfieldUltrasoundOther:Microwave,laser….RadiationIonization:非粒子輻射X,r–rayNon-ionization:又稱為粒子輻射Particle:X-raybasicprincipleX-rayintroductionWhatisX-ray?InteractionsbetweenX-rayandMatter(1)CoherentScattering(2)PhotoelectricEffect(3)ComptonScattering(4)Pairproduction(5)PhotodisintegrationCoherentscatteringPhotoelectriceffectComptonScatterParproductionX-RAYDTETCTORSToproduceanimagefromtheattenuatedX-raybeam,theX-raysneedtobecapturedandconvertedtoimageinformation.TwosystemfortheX-RAYdetectors:Screen-FilmdetectorDetectorsforcomputerradiographySchematicrepresentationoftheradiographicimagechainX-raytubeX-rayTubeX-raygeneratorX-raydetectorsX-rayFilmTheX-rayFilmisaphotographicfilmconsistingofatransparentplasticsubstratemadeofacetateorpolyesterusuallycoatedonbothsideswithalight-sensitiveemulsion.OpticalDensityD=Log10(Ii/It)D:theopticaldensityIi:incidentlightintensityIt:transmittedlightintensityX-rayFilmDouble–EmulsionFilmThefilmusedindailyradiologicalpracticeiscoatedonbothsidesofthefilmsubstrate.Itpreventsbendingofthefilm,becausethefilmwillbendifcoatedonlyonesidewhentheemulsionbecomesdryandshrink.Itdoublesfilmcontrast.診斷型X光機血管攝影X光機移動型X光機與C型X光機數位型X光機數位化X光機(DigitalRadiographicSystem

ClinicalApplicationClinicalApplication傳統式X光的缺點2Dprojectionof3DstructureLostdepthinformationOverlappingplaneCannotdiffersofttissueCannotquantitativeX-RaysComputerTomographyBasicScanningprodureinCTBasicScanningprodureinCTCTgenerationFirstgeneration:onex-raytube,onedetectorSecondarygeneration:onex-raytube,manydetectorsThirdgeneration:onex-raytube,archdetectorarrayFourthgeneration:circulardetector,onex-raytubeThebasicinternalgeometryofathird-generationspiralCTscannerSingle–SliceandMulti-SliceCTMulti-SliceCTdetectorarrayDynamicSpatialreconstructionSystemDynamicSpatialreconstructionSystemElectronbeamCTHalfarchtargetArchdetectorarray

ElectronbeamCT電腦斷層攝影機電腦斷層掃描儀

1970年代中期電腦斷層掃瞄儀(CT)的出現，使得傳統醫療診斷影像產生革命性的演進。CTimage-BrainBrainStudy,variableslicethicknesses.

Thereare3imagesinthisseries.

HiSpeedNX/iImages

CTimage-ChestLightSpeedSeriesCTimage-ChestHiSpeedX/iSeriesThoraxstudy,0.7secscantime,auto-mAmode.

CTimage-SpineLightSpeedSeriesImagesandCaseStudies-SpineNRIintroductionNuclearmagneticresonance(NMR)isachemicalanalyticaltechniquethathasbeenusedforover50years.ImagetechniquecallMRI.MRIintroductionNon-ionizingradiationMinimallyinvasiveCapableofprovidingexcellentsoft-tissuecontrastwithimaginginanyarbitraryplaneTherecentdevelopmentofflowimagingprovidesthepassivityofperformingNMRangiographyMRIintroduction1946F.BlockandE.PurcellSpectroscopictechniqueinchemistryandphysics1952BlockandPurcellawardedNobelPrize1973NMRappliedtoimagingtechnique1973~NRIinclinicalfieldMRIbasicprincipleEMwaveC=3*108m/secByMaxwell’swavetheoryE:electricfieldB:magneticfieldEandBhassamefrequency

EMwaveapplicationlistMRIprincipleMRIprincipleSpinMRIprincipleMRIbasicprincipleAnyspinningchargeparticlecreatesanEMfieldSpinquantummember“s”s(1H)=1/2Thenumberofenergystatesofanucleususdeterminedbytheformula#ofenergystat=2s+1MRIbasicprincipleLarmorequation

MRIBasicprincipleMRIBasicprincipleMRIimagehardwareMRIcoilMRIimagehardwareMRIImageDrawingoftheabdominal/pelviscoil.Sagittalpelvisimageobtainedusingtheabdominal/pelviscoil.

Bilateralhipimageobtainedusing

theabdominal/pelviscoil.

0.5T磁振造影機0.5TSIGNAContour磁共振儀

1.5T磁振攝影機1.5TSIGNAMR/i磁共振儀

3T磁振造影機3.0TSIGNAMR

高磁場磁共振儀

高磁場全身性掃瞄磁共振儀,其特殊的性能可滿足您臨床領域與專業研究的需求.尤其於神經方面的應用:RealTime功能性影像,DWI,頻譜分析.MRIimageprincipleMRIimageprincipleMRIimageprincipleMRIimagereconstructionMRIimagereconstructionMRIimage-AngiographyAxialhead,22cmFOV,45.6mmThk,GE(20o),TR/TE=33.33/3ms,1Nex,256x224matrixMRIimage-NeckCoronalheadwithpathology,22cmFOV,2.5mmThk,GE(30o),TR/TE=11/2ms,1Nex,256x192matrixMRIimage-spineSagittallumbarspine,32cmFOV,3mmThk,256x256matrix,2Nex,SE

A)TR/TE=600/15

B)TR/TE=4000/96

C)TR/TE=2000/16ABCWhatisNuclearmedicine?

NuclearmedicineFunctionalimagestudyEmissiondetectionRadionuclideandPharmaceuticalShorthalflife,lowradiation

核醫診斷常用之同位素伽傌閃爍造影機GammaCameraPMT(光電倍增管)GammacameradetectorImageapplication Image