Tc99在心血管影像中的应用优选课件.ppt

2020/10/18,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,Tc,99,Used In Cardiac Heart Imaging,2020/10/18,1,Tc99 Used In Cardiac Heart Ima,Outline,Background of Nuclear Cardiology,Elements Used in Heart Imaging,Imaging Techniques,Heart Images,2020/10/18,2,OutlineBackground of Nuclear C,Background of Nuclear Cardiology,Nuclear cardiology imaging procedures have vastly developed over the past 25 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.,2020/10/18,3,Background of Nuclear Cardiolo,Instrumentation of Nuclear Imaging,Uses 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 Photon Emission Computerized Tomography(SPECT).,Tc,99,is the most common radionuclide used today in cardiac imaging.,2020/10/18,4,Instrumentation of Nuclear Ima,Nuclear Cardiology Camera,2020/10/18,5,Nuclear Cardiology Camera2020/,The Thallius Ion(,201,Tl),The first use of radiopharmaceuticals in cardiac heart imaging began in 1975 in which the thallius ion was used.,2020/10/18,6,The Thallius Ion(201Tl)The fi,Problems with Thallium,Limited Sensitivity/Accuracy,80%,Short half life,Does not stay bound to tissue,Images must be taken quickly due to redistribution.,Difficult to concentrate target organ.,2020/10/18,7,Problems with ThalliumLimited,Technetium,75%of procedures uses technetium,99,in diagnosing cardiac diseases.,Half-life of 6 hours,140 KeV gamma ray emission,High enough in energy to penetrate the bodys tissues,but low enough not to harm the body.,Two types of technetium to be discussed,1)Tc,99,TBI,2)Tc,99,Sestamibi,2020/10/18,8,Technetium 75%of procedures,Technetium,99,TBI,1,st,Technicium compound introduced to nuclear cardiac imaging,Structural Name,Hexakis-(t-butylisonitrile)-Technetium(I),Six Coordinate Isonitrile,Octahedral geometry,+1 oxidation state,2020/10/18,9,Technetium99 TBI1st Techniciu,Structure of Tc,99,TBI,2020/10/18,10,Structure of Tc99 TBI2020/10/1,Problems with Tc,99,TBI,High activity in other parts of the body.,Redistribution,2020/10/18,11,Problems with Tc99 TBIHigh act,Tc,99,Sestamibi(MIBI),Derived,from Tc,99,TBI,Composed of functional groups that give clearance from non-target organs,Six coordinate,Octahedral geometry,Greater hydrophilicity than Tc TBI due to its methoxy groups.,Lypophillic,2020/10/18,12,Tc99 Sestamibi(MIBI)Derived f,Structure of Tc,99,Sestamibi,2020/10/18,13,Structure of Tc99 Sestamibi202,Tc,99,MIBI Technique,One Day Stress Protocol,Two Day Stress Protocol,Dual Isotope Scanning,Gating,LVEF(Left Ventricle Ejection Fraction),2020/10/18,14,Tc99 MIBI TechniqueOne Day Str,One Day Stress Protocol,One day,Consists of a rest exam followed by a stress exam in the same day.,Injection of Tc MIBI is performed after a rest test and after a stress test.,1,st,injection is a low dose,2,nd,injection is a higher dose(3X the rest injection),Problems,Not accurate in some instances,2020/10/18,15,One Day Stress ProtocolOne day,Two Day Stress Protocol,Two Day,Conducted only if the one day test was unsuccessful.,Rest study not necessary if stress test was normal.,Problems,Same as with the one day,2020/10/18,16,Two Day Stress ProtocolTwo Day,Dual Isotope Scanning,Rest test with Thallium study conducted on day one,Thallium redistributes so other testing can be performed,Stress test with Technetium study is conducted on day two,Drawbacks,Different resolution makes it difficult to compare heart images.,2020/10/18,17,Dual Isotope ScanningRest test,Gating,Most popular in nuclear heart imaging.,Improves diagnostic accuracy of SPECT imaging.,Sharper,clearer images than other techniques.,Accesses regional wall motion and left ventricular ejection fraction.,Provides information regarding myocardial systolic functions and prognosis.,Allows an ejection fraction to be calculated.,2020/10/18,18,GatingMost popular in nuclear,Left Ventricle Ejection Fractions,Provides prognostic information for the risk of heart diseases by using the gated 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,.,2020/10/18,19,Left Ventricle Ejection Fracti,What the images mean,Thickened,brighter images on SPECT scans indicates viable heart tissue.,Thinner image indicates that there is possible scarring or infarction of the heart.,2020/10/18,20,What the images meanThickened,Normal vs Abnormal Heart Image,Left Image-abnorm。