Tc-在心血管影像中的應(yīng)用課件

1、Tc99 Used In Cardiac Heart ImagingTc99 Used In Cardiac Heart ImaOutlineBackground of Nuclear CardiologyElements Used in Heart ImagingImaging TechniquesHeart ImagesOutlineBackground of Nuclear CBackground of Nuclear CardiologyNuclear cardiology imaging procedures have vastly developed over the past 2

2、5 years with advantages and treatments of heart disease.Myocardial perfusion imaging (MPI) offers a high degree of accuracy in the detection, diagnosis, and prognosis of coronary artery disease.MPI is the most common procedure in determining heart disease.Background of Nuclear CardioloInstrumentatio

3、n of Nuclear ImagingUses radiopharmaceuticals that localize to a target organ.In the case of cardiology, imaging agents are used that will flow to and accumulate in the myocardium of the heart.Nuclear heart imaging is performed with a nuclear camera.The heart imaging process is referred to as Single

4、 Photon Emission Computerized Tomography (SPECT).Tc99 is the most common radionuclide used today in cardiac imaging.Instrumentation of Nuclear ImaNuclear Cardiology CameraNuclear Cardiology CameraThe Thallius Ion (201Tl)The first use of radiopharmaceuticals in cardiac heart imaging began in 1975 in

5、which the thallius ion was used.The Thallius Ion (201Tl)The fiProblems with ThalliumLimited Sensitivity/Accuracy80 %Short half lifeDoes not stay bound to tissue Images must be taken quickly due to redistribution.Difficult to concentrate target organ. Problems with ThalliumLimited Technetium 75 % of

6、procedures uses technetium99 in diagnosing cardiac diseases.Half-life of 6 hours140 KeV gamma ray emissionHigh enough in energy to penetrate the bodys tissues, but low enough not to harm the body.Two types of technetium to be discussed1) Tc99 TBI 2) Tc99 SestamibiTechnetium 75 % of procedures Techne

7、tium99 TBI1st Technicium compound introduced to nuclear cardiac imagingStructural NameHexakis-(t-butylisonitrile)-Technetium(I)Six Coordinate IsonitrileOctahedral geometry+1 oxidation stateTechnetium99 TBI1st TechniciuStructure of Tc99 TBIStructure of Tc99 TBIProblems with Tc99 TBIHigh activity in o

8、ther parts of the body.RedistributionProblems with Tc99 TBIHigh actTc99 Sestamibi (MIBI)Derived from Tc99 TBIComposed of functional groups that give clearance from non-target organsSix coordinateOctahedral geometryGreater hydrophilicity than Tc TBI due to its methoxy groups.LypophillicTc99 Sestamibi

9、 (MIBI)Derived fStructure of Tc99 SestamibiStructure of Tc99 SestamibiTc99 MIBI TechniqueOne Day Stress ProtocolTwo Day Stress ProtocolDual Isotope ScanningGatingLVEF (Left Ventricle Ejection Fraction)Tc99 MIBI TechniqueOne Day StrOne Day Stress ProtocolOne dayConsists of a rest exam followed by a s

10、tress exam in the same day.Injection of Tc MIBI is performed after a rest test and after a stress test.1st injection is a low dose2nd injection is a higher dose (3X the rest injection)ProblemsNot accurate in some instancesOne Day Stress ProtocolOne dayTwo Day Stress ProtocolTwo DayConducted only if

11、the one day test was unsuccessful.Rest study not necessary if stress test was normal.ProblemsSame as with the one dayTwo Day Stress ProtocolTwo DayDual Isotope ScanningRest test with Thallium study conducted on day oneThallium redistributes so other testing can be performedStress test with Technetiu

12、m study is conducted on day twoDrawbacksDifferent resolution makes it difficult to compare heart images.Dual Isotope ScanningRest testGatingMost popular in nuclear heart imaging.Improves diagnostic accuracy of SPECT imaging.Sharper, clearer images than other techniques.Accesses regional wall motion

13、and left ventricular ejection fraction.Provides information regarding myocardial systolic functions and prognosis.Allows an ejection fraction to be calculated.GatingMost popular in nuclear Left Ventricle Ejection FractionsProvides prognostic information for the risk of heart diseases by using the ga

14、ted SPECT.Left ventricle is where most of the heart function is measured since it pumps blood throughout the body.Measures the amount of blood that the left ventricle pumps out per beat.EF of less than 40% are at risk of some sort of cardiac event.EF of less than 30% are at risk for cardiac death.Le

15、ft Ventricle Ejection FractiWhat the images meanThickened, brighter images on SPECT scans indicates viable heart tissue.Thinner image indicates that there is possible scarring or infarction of the heart.What the images meanThickened,Normal vs Abnormal Heart ImageLeft Image-abnormalRight Image-normal

16、Normal vs Abnormal Heart ImagePrognosis Using Tc Heart ImagingPositive MIBI scans are nearly 100 % accurate.Negative MIBI scans are just as accurate.Prognosis Using Tc Heart ImagiConclusionTc MIBI is the best radionuclear heart imaging agent used today.Allows many imaging techniques to be performed

17、that are critical for diagnosing heart diseases.ConclusionTc MIBI is the best ReferencesJurisson, S. “Coordination Compounds in Nuclear Medicine.” Chemical Reviews. 1993, 93, 1137-1156.Holman, Sporn, Jones, et al. “Myocardial Imaging with Technetium 99 CPI: Initial Experience in the Human”, The Journal of Nuclear Medicine.Angelberger, P. “Tc-99m (Tc-