Essentials of Nuclear Medicine Physics, Instrumentation, and Radiation Biology. Rachel A. Powsner
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      3 Chapter 3Figure 3.1 99mTechnetium generator.Figure 3.2 Transient equilibrium.Figure 3.3 Transient equilibrium in a 99Mo–99mTc generator.Figure 3.4 Secular equilibrium.Figure 3.5 Cyclotron.Figure 3.6 Schematic of a nuclear reactor.Figure 3.7 Chain reaction involving 235U and slow neutrons.Figure 3.8 Neutron capture by target nuclide placed in a reactor. Thermal (s...

      4 Chapter 4Figure 4.1 Simple gas‐filled detector.Figure 4.2 The presence of ionizing radiation is detected by a deflection of...Figure 4.3 Current as a function of applied voltage in a gas detector. The r...Figure 4.4 Proportional counter. The voltage causes gas amplification that g...Figure 4.5 Geiger counter. The primary radiation rapidly triggers a cascade ...Figure 4.6 Continuous discharge. The voltage applied to a neon sign is high ...Figure 4.7 Ionization by alpha and beta particles and by photons in the gas‐...Figure 4.8 Geometric efficiency of detectors. The closer the detector is to ...Figure 4.9 Dose calibrator.Figure 4.10 Pocket dosimeter. Ions produced in the gas neutralize the charge...Figure 4.11 Geiger probe.Figure 4.12 Quenching. Top: Filler atoms absorb extra energy in addition to ...Figure 4.13 (a) Pure silicon crystal with shared outer shell electrons. (b) ...Figure 4.14 Depletion zone is created after the free electrons and positive ...Figure 4.15 The depletion zone is widened by the application of a high volta...Figure 4.16 An incoming photon impacts an atom in the depletion zone causing...Figure 4.17 Each cell within the silicon photomultiplier is composed of a si...Figure 4.18 The large number of cells within a silicon photomultiplier resul...Figure 4.19 Film badge. The strips of metal absorbers assist in estimating t...Figure 4.20 Luminescent crystals: (a) Photons strike crystal. (b) Electrons ...Figure 4.21 Luminescent crystals without (a) and with “doping” (b). Atoms us...Figure 4.22 Thermoluminescent and optically luminescent crystals. (a) Photon...

      5 Chapter 5Figure 5.1 Scintillation crystal. The sodium iodide crystal “doped” with a t...Figure 5.2 Light photons. (a) Gamma rays eject electrons from the crystal th...Figure 5.3 Thick crystals stop a larger fraction of the photons.Figure 5.4 Sodium iodide crystal scintillation detector.Figure 5.5 Photomultiplier tube and its amplifier.Figure 5.6 Pulse‐height analyzer. The incoming pulse (Z‐pulse) is proportion...Figure 5.7 Blurring of photopeak due in part to statistical variation in the...Figure 5.8 Compton peak (edge).Figure 5.9 Iodine escape peak.Figure 5.10 Annihilation peaks.Figure 5.11 Coincidence peak for 111In equals the sum of the individual phot...Figure 5.12 The effect of water on the 51Cr energy spectrum.Figure 5.13 Thyroid probe. Shielded crystal scintillation detector as used f...Figure 5.14 Well counter. Crystal scintillation detector constructed with an...

      6 Chapter 6Figure 6.1 Components of a standard nuclear medicine imaging system.Figure 6.2 Collimator detail.Figure 6.3 A collimator selects photons perpendicular to the plane of the co...Figure 6.4 Without a collimator, angled photons introduce improperly located...Figure 6.5 For the same bore length, the smaller the diameter the higher the...Figure 6.6 For the same hole diameter, the longer the bore the higher the re...Figure 6.7 Angle of acceptance. The narrower the angle of acceptance of a co...Figure 6.8 Higher energy photons can pass through thinner collimator septa (...Figure 6.9 Blurring of a line source.Figure 6.10 Full‐width at half‐maximum and full‐width at tenth‐maximum.Figure 6.11 Modulation transfer function.Figure 6.12 Parallel‐hole collimator.Figure 6.13 Converging collimator.Figure 6.14 Diverging collimator.Figure 6.15 Pinhole collimator.Figure 6.16 (a) In a converging collimator, holes converge toward the patien...Figure 6.17 Scattering of photons in a thicker crystal reduces resolution.Figure 6.18 The positioning algorithm improves image resolution. The closer ...Figure 6.19 Pixel address: column number, row number.Figure 6.20 Storing image data in a matrix.Figure 6.21 Effect of matrix configuration on image resolution.Figure 6.22 A matrix cannot resolve points separated by less than 1 pixel.Figure 6.23 Bone scan.Figure 6.24 Sixty‐second renal flow study.Figure 6.25 Gastrointestinal bleeding scan.Figure 6.26 Gated blood pool study.

      7 Chapter 7Figure 7.1 SPECT camera.Figure 7.2 Two‐headed SPECT camera configurations.Figure 7.3 Projection views from a SPECT acquisition.Figure 7.4 Five‐view planar liver–spleen scan.Figure 7.5 180° cardiac SPECT.Figure 7.6 Step‐and‐shoot acquisition.Figure 7.7 Continuous acquisition.Figure 7.8 Circular, elliptical, and body contouring orbits.Figure 7.9 (a) Slices through the level of the heart from selected projectio...Figure 7.10 Sinograms at selected positions along the long axis of the body ...Figure 7.11 Effects of patient motion in the X‐ and Y‐directions on sinogram...Figure 7.12 First, third, fifth rows: artifacts created by patient motion (a...Figure 7.13 Newer cardiac SPECT cameras. (a) Multiple heads. (b) Stationary ...

      8 Chapter 8Figure 8.1 Annihilation reaction.Figure 8.2 Line of response and examples of coincident events.Figure 8.3 Singles events.Figure 8.4 Random events.Figure 8.5 Time‐of‐flight PET systems.Figure 8.6 Current limitation in time‐of‐flight technology.Figure 8.7 PET camera.Figure 8.8 Slits between crystals direct light photons toward PMTs.Figure 8.9 A coincident event is accepted after processing by the pulse heig...Figure 8.10 One of a pair of annihilation photons is scattered and their dat...Figure 8.11 Random events can “pass” as true coincidence events.Figure 8.12 Two‐dimensional and three‐dimensional PET imaging.Figure 8.13 Factors limiting resolution in PET imaging. (a) The positron tra...Figure 8.14 (a and b). Parallax error affects resolution near periphery of f...Figure 8.15 Attenuation is constant across a line connecting two detectors....

      9 Chapter 9Figure 9.1 Basic components of an X‐ray tube.Figure 9.2 X‐rays are generated when electrons strike the tungsten target.Figure 9.3 X‐ray spectrumFigure 9.4 The filter attenuates the lower energy X‐rays (depicted as short ...Figure 9.5 Basic components of one type of CT scanner containing a stationar...Figure 9.6 Rotate–stationary configuration. A rotating source and collimator...Figure 9.7 Rotate–rotate configuration. Opposing source and detector rotate ...Figure 9.8 Multislice CT detector array composed of multiple rows of detecto...Figure 9.9 Grouping detector rows allows acquisition of slices of varying wi...Figure 9.10 Axial versus helical scanning.Figure 9.11 Pitch.Figure 9.12 Cone beam CT. A large flat panel detector is combined with a con...

      10 Chapter 10Figure 10.1 Spin (angular momentum) is represented by a vertical arrow throu...Figure 10.2 Current direction is denoted as moving in the opposite direction...Figure 10.3 Moving electric charge through a straight wire creates a circumf...Figure 10.4 Moving electric charge through a wire coil creates a nearly line...Figure 10.5 The spin angular momentum and the magnetic moment of a subatomic...Figure 10.6 (a) Sum magnetization of a sample of protons is zero until (b) a...Figure 10.7 The external magnetic field causes M to precess or wobble around...Figure 10.8 Application of a 90‐degree radiofrequency pulse perpendicular to...Figure 10.9 Following the RF pulse M precesses in the X‐Y plane (therefore i...Figure 10.10 180‐degree radiofrequency pulse. Top image: A longer RF pulse t...Figure 10.11 The precessing magnetic vector (MXY) generates an electric curr...Figure 10.12 T1 recovery after the radiofrequency pulse. T1 is the time СКАЧАТЬ