核醫(yī)學課件 2016年七年制 雙語緒論 基礎 核醫(yī)學儀器

個人簡介

謝永雙，中共黨員，副教授，2004年碩士研究生畢業(yè)，2012-2013年曾到美國UCLA大學訪問學習

個人簡介

廣西醫(yī)科大學核醫(yī)學教研室教師一附院核醫(yī)學科副主任醫(yī)師負責五年制班、本碩班、全英班的核醫(yī)學教學，主要本碩班、全英班的教學;負責核醫(yī)學的臨床工作

NuclearMedicine

IntroductionNuclearmedicinedepartmentofGuangxiMedicalUniversity

Xieyongshuang

NuclearMedicineDefinitionContentMaincharacteristicHistoryreviewandpresentsituationDefinitionItisadiscipline

thatexploitsthepropertiesradioactiveformsofvariouselementsinthediagnosisandtreatmentofdisease.MainContentsExperimentalNuclearMedicineClinicalNuclearMedicineRadionuclidetracingtechniqueRadionuclidedynamicanalysisInvitroradioassayRadioautographyandactivationanalysis

ExperimentalNuclearMedicinediagnosticnuclearmedicinetherapeuticnuclearmedicine

ClinicalNuclearMedicineNuclearMedicineExperimentalnuclearmedicineClinicalnuclearmedicine

TracingtechniqueDynamicanalysisInvitroradioassayRadioautographyActivationanalysisDiagnosisTherapyInvivoInvitroImagingFunctionExternalirradiationinternalirradiationRadioimmunoassayImmunoradiometricassayNuclearMedicineInimaging

theradiopharmaceuticalsaredetectedbyspecialtypesofcamerasthatworkwithcomputerstoprovideveryprecisepicturesabouttheareaofthebodybeingimaged.NuclearMedicineimagingNuclearMedicineIntreatment,theradiopharmaceuticalsgodirectlytotheorganbeingtreated.

Maincharacteristicofnuclearmedicinestructureandfunctionimagingidentifyabnormalitiesveryearlier

thanotherdiagnostictestBeingsafe,painless,andcost-effectiveCharacter

Bothstructureandfunction.

CharactermoreealierCharactermoresafetyHistoryreviewandpresentsituationNuclearMedicine核醫(yī)學是一門年輕的學科，從1896年發(fā)現放射現象至今也只有114年的歷史，而從核醫(yī)學的起源到現在僅幾十年，真正形成核醫(yī)學學科的歷史則更短。

Becquerel1896年法國物理學家Becquerel發(fā)現了鈾的放射性，第一次認識到放射現象。他在研究鈾鹽時，發(fā)現鈾能使附近黑紙包裹的感光膠片感光，由此斷定鈾能不斷地發(fā)射某種看不見的，穿透力強的射線。1903年與Curie夫人共獲Nobel物理學獎。

HistorylookbackMarieS.Curie

1898年在巴黎的波蘭化學家Curie(1867-1934)與他的丈夫Pierre共同發(fā)現了鐳（即88號元素），他們從30噸瀝青鈾礦中提取了2mg鐳。此后，又發(fā)現了Pu和Th天然放射性元素。1903年Curie與Bequerel共獲Nobel物理學獎，1911年又獲得Nobel化學獎。

HistorylookbackDanlos(1844-1912)

1901年法國醫(yī)師Danlos將放射性鐳與結核的皮膚病變接觸，試圖治療皮膚病，可以說是第一次醫(yī)學應用。

HistorylookbackThefatherofclinicalnuclearmedicine1926年美國Boston內科醫(yī)師

Blumgart首先應用放射性氡研究循環(huán)時間，第一次應用了示蹤技術（將氡從一側手臂靜脈注射后，在暗室中通過云母窗觀察其在另一手臂出現的時間，以了解動-靜脈血管床之間的循環(huán)時間），后來他又進行了多領域的生理、病理和藥理學研究。被譽為”臨床核醫(yī)學之父”。

HistorylookbackThefatherofexperimentalnuclearmedicine

美國化學家Hevesy，最早將同位素示蹤技術用于植物的研究、人體全身含水量等生理學研究，并發(fā)明了中子活化分析技術。于1943年獲得了Nobel獎金。并被稱為Thefatherofexperimentalnuclearmedicine。

HistorylookbackErnestLawrence1930年美國加州大學校園里，物理學家ErnestLawrence生產出一個回旋加速器，并生產出多種同位素。1936年，他的兄弟，內科醫(yī)師JohnLawrence首先用P-32治療白血病。1939年獲物理獎。

HistorylookbackModerncyclotronIreneCurie&FredericJoliot1934年，法國放射化學家Curie和她的丈夫Joliot用a粒子照射Al產生放射性30P,第一次用人工核反應方法生產出放射性核素。同年Fermi等人用中子源轟擊靶核生產出多種核素。DavidKuhl1952年美國Pennsylvania大學一年級醫(yī)學生DavidKuhl設計了掃描機光點打印法。1959年他又用雙探頭的掃描機進行斷層掃描，并進一步研制和完善斷層顯像儀器，使得SPECT和PET成為核醫(yī)學顯像的主要方法。1996年獲得了“

Cassenaward”，被稱為Thefatherofemissiontomography?？梢哉J為，沒有他的遠見，核醫(yī)學有可能不會發(fā)展成為具有特色的專業(yè)。

HistorylookbackThefatherofemissiontomographyAnger

andγcamera1957年Anger研制出第一臺γ照相機，稱之為Anger照相機，1963年在日內瓦原子能和平會議上展出。它克服了逐點掃描打印的不足，使核醫(yī)學顯像走向現代化階段。HistoryreviewBerson&Yalow1960年美國的Berson和Yalow將核技術與免疫學技術相結合建立了放射免疫分析法，并首先用于測定血漿胰島素濃度，由于該法對醫(yī)學的巨大貢獻，1977年Yalow獲得了NobelPrize。YalowBersonHistoryreviewRadioimmunoassay顯像儀器的發(fā)展：

直線掃描機γ照相機SPECT

符合線路SPECTPETCT/PET與

CT/SPECT。核醫(yī)學的現狀與進展分子核醫(yī)學的形成：應用核醫(yī)學示蹤技術從分子水平認識疾病，為臨床診斷、治療和疾病的研究提供分子水平信息甚至分子水平的治療手段。使醫(yī)學影像技術走向“分子影像”時代。核醫(yī)學的現狀與進展Molecularnuclearmedicine受體密度與功能基因的異常表達生化代謝變化細胞信息傳導臨床診斷臨床治療疾病研究提供分子水平信息分子水平治療手段分子核醫(yī)學的形成分子影像學的形成治療核醫(yī)學的形成與發(fā)展

1901年鐳結核性皮膚病灶

1903年鐳近距離腫瘤治療

1905年鐳突眼性甲狀腺腫……1939年

32P白血病

1942年

131I甲狀腺功能亢進癥……

核醫(yī)學的現狀與進展治療核醫(yī)學的形成與發(fā)展

核素治療與化療、放療的本質區(qū)別：利用核射線治療疾病治療藥物對病變組織具有選擇性治療作用持久方法安全、簡便

核醫(yī)學的現狀與進展治療核醫(yī)學的形成與發(fā)展

發(fā)展方向：放射性核素的研究攜帶放射性核素的載體研究

具有前景的研究領域：放射免疫靶向治療受體介導的靶向治療放射性核素基因治療放射性核素微粒腫瘤組織間定向植入治療

核醫(yī)學的現狀與進展BasicPhysicsofNuclearKLMAtomneutronsprotonsnucleon+electrons- ConfigurationofAtomAtomNucleusProtonQuark10-8cm10-12cm10-13cm<10-16cmshellBasicconceptIsotope:Therearethesameprotons,but

differentmassnumber(orneutrons).Isomer:

Therearethesameprotons,neutronsandelectrons;however,theycontainadifferentamountofnuclearenergy.Nuclide:

anuclideisanyindividualatomicspecies,whichcanbedistinguishedbyitsatomicweight,

atomic

number,andatomicenergystate.Stable&radionuclide★Stablenuclidewillnotdecay.Approximately280ofthenuclidesareinastableform.★Radionuclidesareunstableand

spontaneouslyreleaseenergyorsubatomicparticlesinanattempttoreachamorestablestate.Thereareapproximately1500radionuclides.NucleardecayTherearefivekindsofnucleardecay:AlphaDecayBetaDecay(NegativeBetaDecay)PositronEmission(PositiveBetaDecay)GammadecayElectron(orK)CaptureorinternalconversionNucleardecayAlpha(α)decay

Alphaparticlesisaheliumnucleiconsistingof2protonsand2neutrons.4HeγCharacteristicofalphaparticleαdecayoccursinNuclideofP>82.Velocityofαparticleis20thousandkm/sinvacuum.Itcanbeblockedoffbyapaper,sincetheflightofαparticleisshort.Ionizationismorethan

βparticleBetadecayEmitβparticlesandcaptureorbitalelectrons.Tobeacompaniontoincreaseordecreaseofatomicnumber,butthemassnumberofthenewnucleiisthesame.Includingβ－,β＋andelectroncapture.

Velocityofβparticleis200thousandkm/sinvacuum.Penetrabilityismorethanalphaparticle.β-

decayEmitβ－particlesNeutronrichnucleiNeutronprotonThemassnumberofnewnucleiisthesameastheparentnuclei,

atomicnumberincrease1np+β－

+Qβ－γβ＋

decayEmissionofβ＋particleNeutronpoornucleiAprotontoneutrontransformationArtificialradionuclideβ＋γpn+e+189F—188O+β＋

++0.66MeVElectroncapture,ECAnorbitalelectroniscapturedtoformaneutron.NeutronpoornucleiAprotontoneutronP+e-nCharacteristicX-rayAugerelectronγGammadecayandinternalconversionGammadecaymaybeapartofanotherdecayprocess,suchas,ECor-Metastabletostablestatetransitionandemissionofelectromagnetic(γtransition)Newnucleimassandprotonisthesame,butenergychangedInternalconversionandInternalconversionelectronInternalconversionelectronγrayGammadecayandinternalconversionWhenthenucleusmovesfromahighertoalowerenergy,eitheragammarayisproducedorthedeexcitationenergyisusedtoejectanorbitingelectron.Thislatterprocessiscalledinternalconversion.Thisorbitingelectroniscalledinternalconversionelectron(IE).

CharacteristicofγrayGammarayisphotonNoelectricchargePenetrabilityismorethanchargedparticleLowionizationabilityComparisonofthreedecayalphadecaybetadecaygammadecayMasschangedyesnonoProtonchangedyesyesnoEnergychangedyesyesyesThenumberofatoms(N)ofagivenoriginalpopulation(No)whichwillremainafteragiventimeinterval(t)canbecalculatedbytheequation:N=Noe-λtThelawofnucleardecay

ThelawofnucleardecayDecayformula：N=Noe-λtDecayconstant

：Decayconstantequalstofractionofnucleidecayingperunittime.Characteristic：everyradionuclidehasdifferentλ.Commonness：Thisisthebasicexponentialequationforradioactivedecay.Thisisthebasicexponentialequationforradioactivedecay.Ifdesired,theequationalsocanbewrittenintermsofradioactivity(A).A=Aoe–λtA0Thelawofnucleardecay

HalflifePhysicalhalflife，(T1/2)

thetimeittakesforonehalfoftheoriginalnumberofatomstodecay.

ThelongestT1/2>1010a.TheshortestT1/2

<10-10s.

T1/2=0.693/λ

Whenhalfoftheradiopharmaceuticalwithinthebodyremains,thistimeiscalledthebiologicalhalftime.Biologicalhalflife

Effectivehalflife：Thecombinationofthephysicalhalflifeandthebiologicalhalflifeiscalledtheeffectivehalflife.ThusTeffwillbelessthaneitherthebiologicalorthephysicalhalflife.

RadioactivityActivityisthenumberofatomsdecayingperunittime.Onebecquerel(Bq)equalsonedisintegrationpersecond.

acurie(Ci)

is3.7x1010

BqOtherunit：KBq、MBq、GBq，Ci、mCi、Ci。Interactionofrayandmatter

InteractionofchargedparticleandmatterIonizationandexcitationIonization：α、β→matter→electrons→e-leaveorbit→freeelectron；Chargedparticlee-IonpairsSecondaryionization33.85eVmatter

Excitation：

αandβ→matter→orbite-andgotenergy→low

level→highlevel→excitationstate→deexcitation→CharacteristicX-rayandAugerelectron

Chargedparticleparticleγ(deexcitation)BremsstrahlungAnelectrontraversingamaterialmaycomecloseenoughtothenucleusofanatomthatitissharplydeflectedinitspathduetoitsattractiontotheprotons.Thisaccelerationoftheelectronmayproducewhatistermedabremsstrahlungphoton.

particleX-rayScatteringscatteringisaclassofphenomenabywhichparticlesaredeflectedbycollisionswithotherparticles.particleparticleAnnihilationradiationThepositronisemittedwithacertainamountofkineticenergythatitlosesasitmovesthroughitsenvironment.Whenitcomestorest,itannihilateswithanearbyelectrontoproducetwo511keVannihilatingphotonsmovinginoppositedirections.Thisprocessiscalledannihilationradiation.InteractionofphotonandmatterphotoelectriceffectInphotoelectricabsorption,aphotoninteractswiththeatom,losingallitsenergyintheprocess.Aninnershellelectron(usuallyaKshellelectron)isejectedfromtheatom.Theprocessiscalledphotoelectriceffect.

XrayAugerelectronphotoelectronγKLElectronvacancyfilledMe-IncidentphotonPhotoelectriceffectComptoneffectEnergyrange：Severalto0.5MeVPartenergygiveorbitalelectronsResidualenergygivescatteredphotonIncidenceγComptone-scatteringγElasticcollisionKLMElectronpairproductionPhotonenergygreaterthan1.02MeVpassesnearthehighelectricfieldofthenucleusincidenceγγγ511keV511keV+e-freeelectrone-e+NuclearMedicineInstrumentationNuclearMedicineInstrumentationWhatisNuclearMedicineInstrumentation?Howdoesitwork?1.conceptionNuclearmedicineinstrumentationisessentialfornuclearmedicineclinicalpracticeandresearch.imaginginstrumentationnon-imaginginstrumentationIntroductionBasicprinciple

interactionofrayandmatter

Chargedparticle:ionization,

excitation

γphoton:photoelectriceffect

electronpaircomptoneffect

Basicconfiguration

Radiationdetector

theenergyofthegammaphotontothepulsesofelectricalcurrenttransformation.Electronicspart

differentdevicefordifferentneed.Schematicdiagramof

scintillationdetectorconfiguration

Scintillationdetector

Electroniccircuitry

Recordingdevice

Scaler

Countratemeter

Imagingequipment

Scintillationcounter

Functiondeterminationdeviceγcamera、ECTMainlytypeofdetectorTherearemanykindsofdetector.γScintillationdetector

arethemostimportantintracerimaging.γScintillationdetectorAradiationdetectorofthetypeutilizedinnuclearmedicinebasicallyactsasatransducerwhichtransformsincomingradiation(gammaphotons)intovisiblelight(lightphotons).Thisisthepropertywhichmadetheseradiationdetectorsknownasγscintillationdetector.γScintillationdetectorNaI(Tl)crystalPhotomultiplier(PMT)Pre-amplitierImaginginstrument

γCamera

SPECTPETCoincidencecircuitSPECT

GammaScintillationCameraThemaininstrumentfornuclearmedicineimagingisthelargefieldofgammacamera,Firstdevelopedin1956byHalAnger.thisdevicehasbecomethemainimagingtoolofnuclearmedicine.GammaScintillationCameraItisconsistsof:aleadcollimator;ascintillationcrystal;anarrayofphotomultipliertubesonthecrystal;apositioninglogicnetwork;apulseheightanalyzer;andanimagerecordinganddisplaydevice,whichistypicallyacomputersystem.GammaScintillationCameraTomographydevice

ECT：Emissioncomputedtomography

SPECT:singlephotonECT

(one-head,two-head)

PET:positronemissiontomography

SPECTSPECTisperformedwitharotatingAngercameramountedonaspecialgantrythatallows360-degreerotationaroundthepatient.One-headSPECTMostmodernimagingdeviceshavetheabilitytodemonstrateinternalstructuresorfunctinalinformationasasectionalsliceTwo-headSPECT

GEtwo-headSPECTtomographyWholebodyimaging

Siemenstri-headSPECTSPECTimaging

ComparisonofECTandCT,MRI

ECTimagingisfunctionandstructureimaging,butstructureimagingisn’tclearlikeCT,MRIimaging.CT,MRIimagingisstructureimaging.ECTimagingshowsacrosssectionofabodywithadistributedradiopharmaceuticalemittingγ-ray.CTimagingshowsacrosssectionofabodywithaexternalsourceemittingX-ray.CoincidencecircuitSPECTSPECTsystemsusedwithoutcollimatorsinacoincidencemodeiscoincidencecircuitSPECTwhichcanbeusedtodetectthetwo511-keVannihilationphotons.PETOneofthemostexcitingtomographictechniquesispositronemissiontomographyscanning.Positronemittingradionuclidesareusedwiththistechnique.原理

采用一系列成對的互成180度排列后接符合線路的探頭，在體外探測示蹤劑所產生之湮沒輻射的光子，采集的信息通過計算機處理，顯示出靶器官的斷層圖象并給出定量生理參數。SiemensPETPETPETPETtracersDecaysbyemittingapositr