《the basic physics of radiation therapy P671》求取 ⇩

Ⅰ．SIMPLE MATHEMATICS OF RADIATION THERAPY3

Proportion3

Simple direct proportion3

Algebraic or arithmetic proportion3

Geometric proportion5

Graphic proportion5

Simple inverse proportion7

Algebraic inverse proportion7

Graphic inverse proportion8

Inverse square proportion9

Algebraic inverse square proportion10

Geometric inverse square proportion11

Graphic inverse square proportion12

Mathematical law of decay13

Decimal system and scientific notation17

The slide rule20

Ⅱ．MATTER AND ENERGY27

Historical background27

Ancient theories27

Dalton＇s theory27

Avogadro＇s law28

Prout＇s hypothesis28

Arrhenius＇ theory29

Avogadro＇s number29

States of matter31

Structure of the atom32

Historical background32

Present concept34

Atomic number39

Mass number39

Equivalence of mass and energy41

Ⅲ．THE NATURE OF RADIATION46

Definition46

Types of radiation46

Electromagnetic radiation47

Quantum theory49

X-rays51

Production51

X-ray spectra52

Properties of x-rays54

Bremsstrahlung (brems radiation)55

Gamma-rays56

Source56

Properties58

Energy59

Radiation of particles61

Alpha-particles62

Beta-particles68

Neutrons71

Electrons74

Positrons74

Cosmic rays75

Summary76

Ⅳ．REACTIONS BETWEEN RADIATION AND MATTER78

Photon interactions with matter78

Transmission of photons79

Unmodified or classical scattering79

Photoelectric interaction with true absorption80

Modified scattering83

Pair production85

Characteristic radiation86

Interactions of particulate radiation with matter91

Alpha-particles91

Beta-particles92

Positrons92

Absorption of photon radiation93

True absorption93

Scattering94

Inverse square law95

The meaning of absorption curves95

Attenuation of a heterogeneous x-ray beam106

Ⅴ．X-RAY PRODUCTION AND CONTROL109

Historical introduction109

Principle of modern production of x-rays111

Conditions necessary for the production of x-rays113

Essential features of a therapy x-ray tube (100-250 Kv)115

Valve tubes119

Construction120

Principle120

Generating and control equipment121

High voltage transformer121

Voltage control devices123

Autotransformer123

Rheostat124

Current control in x-ray tube125

Control of current direction－rectification126

Villard circuit129

Constant potential circuit131

Cables133

High frequency x-ray generator134

Ultra short distance therapy136

Chaoul therapy unit136

Philips therapy unit139

General Electric Maximar-100140

Ⅵ．QUANTITY OF X-RAYS AND GAMMA-RAYS141

Historical introduction141

Modern definition of the roentgen143

Tissue exposure dose in roentgens144

Measurement of the roentgen145

The gamma-ray roentgen148

Victoreen condenser-r-meter149

Other types of dosimeters155

Units of radiation dosage156

Roentgen156

Roentgen equivalent physical157

Rad158

Roentgen equivalent man158

Factors affecting intensity of x-rays159

Kilovoltage159

Milliamperage161

Time161

Distance161

Filtration164

Factors affecting gamma-ray quantity165

Ⅶ．X-RAY QUALITY166

Factors166

Analysis of x- ray beams168

Modification of x-ray beams by filters169

Clinical aspects of x-ray quality－half value layer172

Other methods of specifying x-ray quality179

Equivalent constant potential179

Equivalent wavelength180

Ⅷ．DOSAGE IN X-RAY THERAPY182

Air dose182

Calibration of an x-ray machine182

Errors in dose calibration184

Skin or surface exposure dose186

Area of treatment field188

Depth of irradiated part189

Quality of the x-ray beam191

Tissue or tumor dose191

Absorbed dose191

Central axis depth dose193

Factors in depth dose percentage196

Beam quality196

Depth of lesion201

Area of treatment field202

Treatment distance207

Exit dose209

Isodose charts211

Ⅸ．THERAPY PLANNING214

Tumor localization and verification214

Delimitation of field size217

Cones218

Diaphragms219

Lead shields220

Problem of adjacent or divided ports221

Beam direction223

Protractor223

Pin-and-arc225

Back pointer226

Delivery of adequate radiation dosage227

Crossfire radiation technic227

Isodose curves in therapy planning230

Composite isodose curves233

Determination of dosage at critical points238

Rotation therapy244

Tumor-air ratio method244

Transit dose method252

Grid therapy255

Sources of error in radiation therapy257

Integral dose259

Duties of the x-ray technician in radiotherapy260

Establishment of rapport with patient260

Assisting the radiologist262

Ⅹ．RADIOACTIVE AND NUCLEAR PHYSICS266

Definition266

Historical background266

Nuclides268

Factors in nuclear stability269

Neutron-proton ratio269

Odd-even rules270

Nuclear binding energy270

Nuclear forces271

Exchange forces271

Types of nuclear disintegration272

Alpha-decay272

Beta-decay273

Internal conversion274

K-capture275

Isomeric transition275

Gamma-ray emission276

Artificial radioactivity276

Types of nuclear reactions279

Alpha-particle bombardment280

Neutron bombardment280

Proton bombardment282

Deuteron bombardment282

Gamma-ray bombardment283

The radioactive decay process284

Displacement law284

Radioactive decay scheme286

Radioactive disintegration or decay constant287

The unit of radioactivity296

Specific radiation intensity，Iγ298

Radioactive equilibrium298

Ⅺ．SUPERVOLTAGE GENERATORS AND PARTICLE ACCELERATORS301

Radium alpha-particles301

Particle accelerators302

Van de Graaff generator302

Cyclotron304

Synchrocyclotron308

Betatron310

Synchrotron312

Linear accelerator313

Nuclear reactor317

Neutron physics317

The fission reaction319

Uranium fission322

The nuclear reactor323

Practical applications of nuclear reactor328

Ⅻ．RADIUM AND RADON THERAPY330

Historical survey330

Radium332

Decay and radiations of radium332

Alpha-particles333

Beta-particles334

Gamma-rays335

The radium series336

Radioactive constants of radium337

Disintegration constant338

Half life338

Average life339

Radon339

Source339

Properties340

Radioactive constants341

Radioactive equilibrium341

Gamma-ray dosage determination347

Strength or activity of a radioactive source－the curie349

Comparative dosage of radon and radium－determination of millicurie-hours350

Determination of Iγ for radium354

Absorbed dose－the rad359

Types of radium applicators361

Defects in radium needles363

Gamma-ray therapy planning364

Quimby system366

Surface radium therapy369

Quimby system369

Paterson-Parker system372

Cavitary radium therapy380

Interstitial radium therapy386

Paterson-Parker system389

Martin system399

Quimby system401

Interstitial therapy with radioistopes403

Cobalt-60404

Iridium-192404

Methods of checking accuracy of implant405

ⅩⅢ．SURFACE BETA-RAY THERAPY407

Natural beta-particle emitters408

Radium series408

Radon409

Radium (D + E)411

Artificial beta-particle emitting radionuclides441

Strontium-90411

Radiophosphorus415

ⅩⅣ．SUPERVOLTAGE THERAPY417

Telecurie therapy417

Radium beam units418

Cobalt-60 teletherapy equipment421

Cesium-137 teletherapy equipment425

Supervoltage x-ray equipment428

Comparison with orthovoltage430

Supervoltage treatment planning439

Betatron therapy439

ⅩⅤ．MEDICAL USE OF RADIOACTIVE ISOTOPES444

Radioisotopes in medical diagnosis445

Geiger-Müller tubes447

Principle448

Quenching453

Construction of G-M counters456

G-M counter circuits458

Scintillation counters458

Devices for counting detector pulses462

Scalers463

Count rate meter466

Well counter467

Statistics of counting469

Background469

Statistical error470

Coincidence loss474

General types of counting477

Absolute counting478

Comparative counting480

Properties of radioisotopes480

Decay constant481

Half life481

Average life482

Decay curves482

Units of dosage485

Specific activity485

Effective half life487

Diagnostic use of radioisotopes490

Radioactive iodine in thyroid gland function490

Blood volume studies with I131 serum albumin496

Localization of brain tumors with IHSA498

Radiophosphorus (P32) in the diagnosis of inaccessible tumors499

Radioactive chromium (Cr51) in red blood cell studies501

Cobalt-60 labeled vitamin B12 in pernicious anemia (Schilling test)502

Iron-59 in the study of anemias504

Internal therapy with radioisotopes505

Systemic use of radioisotopes505

Absorbed dose from beta-emitters507

Absorbed dose from gamma-emitters509

Examples of radioisotopes in therapy511

Radioactive iodine (I131)511

Radiophosphorus (P32)514

Radioactive chromic or zirconyl phosphate521

Radiogold (Au198)521

ⅩⅥ．RADIOBIOLOGY524

Physical basis of radiobiology524

The cell530

Normal anatomy530

Elementary genetics532

Malignant cells533

Mode of action of ionizing radiation534

Observable radiation effects on cells536

Radiation effects on cytoplasm539

Effect of radiation on sensitive tumors539

Direct effect542

Indirect effect542

Volume effect543

Effect at a distance543

Tissue recovery after irradiation544

Tissue reactions in radiation therapy552

Acute radiation syndrome556

Modification of radiation injury558

ⅩⅦ．PROTECTION IN RADIOTHERAPY561

The maximum permissible dose561

Determination of whole body exposure566

Personnel monitoring567

Laboratory surveying569

X-ray protection up to 2 Mev570

Radium protection576

Protection from whole body exposure576

Protection from local exposure583

Hazards in the use of radioactive isotopes in Teletherapy584

External radioisotope therapy584

Hazards in the internal use of radioisotopes587

Radioisotope hazards to the patient587

Radioisotope hazards to personnel590

External radioisotope hazards to personnel591

Gamma-radiation591

Beta-radiation594

Exposure of hands to beta- or gamma-radiation595

Internal radioisotope hazards to personnel596

Laboratory design and facilities599

Arrangement and location599

Surface material599

Ventilation600

Shielding600

Decay chamber601

Laboratory monitoring601

Disposal of radioactive wastes602

Decontamination603

Recommendations for nursing procedures604

Special instructions with radioiodine605

Special instructions with radiophosphrous607

Special instructions with radiogold608

Unsafe practices in handling radioisotopes608

Bibliography611

Supplementary References617

Handbooks618

Appendix619

Central axis depth dose data (Tables A to F)620

Useful physical data (Table G)642

Useful equations (Table H)643

The Greek alphabet (Table I)646

Index647