Preface

Radionuclides are useful in many areas of everyday life: archaeology, biology, agronomy, medicine, industry etc. The most spectacular applications include radiochronometry (dating of archaeological objects, sediments and soils for the detection of anthropogenic pollutants, etc.) and nuclear medicine (radiopharmaceuticals used in nuclear medicine imaging, radiotherapy, etc.). The production of electrical energy in nuclear power plants exploits the properties of nuclear fission reactions. Nuclear Physics 2 comprises four chapters devoted respectively to a description of the Big Bang model, a study of the different nucleosynthesis processes, the study of radiochronometers applied to dating and general information on radiopharmaceuticals used in nuclear medicine imaging.

This book, entitled Nuclear Physics 3: Radiopharmaceuticals used in Nuclear Medicine, consists of three chapters.

Chapter 1 is devoted to the study of radiological imaging methods. It begins with a presentation of medical imaging methods and their various medical imaging modalities. It then presents radiological imaging methods such as X-rays, γ-scan (PET) MRI scintigraphy and ultrasound. Next, photoelectric absorption, Compton effect and pair creation coefficients are introduced to express the total attenuation coefficient. The Hounsfield number is expressed as a function of the linear attenuation coefficient of water. The study then focuses on the treatment planning system (TPS), which is used to determine the dose distribution in tumors and surrounding areas during radiotherapy. Following this introduction, the principles of X-ray production, X-ray imaging and computed tomography (CT) or scanner are explained. The computer processing of elementary images to reconstruct the final image of each organ through which X-rays are passed features prominently in this section. The study then turns to nuclear magnetic resonance (NMR), explaining the principle of NMR and its physical model in biological tissues, the quantum model of Larmor precession, the phenomena of excitation and magnetic resonance, and the quantum model of the magnetic resonance phenomenon. The study then turns to magnetic resonance imaging (MRI), with an introduction of the two MRI techniques, closed-field MRI and open-field MRI, T1 and T2 relaxation times, spin–lattice and spin–spin relaxation phenomena, and the phenomenon of the free induction decay (FID) signal according to an exponential in T2* and T2. Following these studies, the NMR imaging sequence – which is a chronological sequence of θ-angle radiofrequency pulses and magnetic field gradients – is introduced. This enables us to study in detail the two main methods of medical imaging sequences: the spin echo sequence and the gradient echo sequence. T1, T2 and proton density weighting of MRI images, as well as the influence of TR repetition time and TE echo time on an NMR imaging sequence, are explained in detail in this section. This is followed by a description of slice planes, slice selection gradient, frequency encoding gradient, phase encoding gradient, Fourier plane, MRI signal decoding and the principle of three-dimensional image acquisition using a triple Fourier transform (3DFT). The chapter concludes with an explanation of the principle of ultrasound imaging and the principle of Doppler ultrasound applied to the exploration of blood flow in a vessel.

Chapter 2 is devoted to the study of technetized radiopharmaceuticals and radiothallium-201 used in nuclear medicine. The chapter begins with a presentation of the main characteristics of the tracers MIBI 99mTc (MIBI = 2-methoxy-isobutylisonitrile), Tetrofosmin 99mTc and 201Tl used in myocardial scintigraphy. The characteristics and dosimetry of conventional gamma cameras and latest-generation CZT (Cadmium Zinc Tellurium) gamma cameras are then presented. The notions of absorbed dose (expressed in gray, symbol Gy), equivalent dose (expressed in sieverts, symbol Sv) and weighting factor (without unit) are then defined. The advantages of tracers technetized on thallium-201 are examined, as are the uses of metastable technetium-99 in scintigraphy. For each of the radiopharmaceuticals or radiotracers considered, dosimetry is presented in tabular form for the various specific organs diagnosed, and the mechanisms by which 99mTc and 201Tl are excreted from the body are described. In addition, the production chains for metastable technetium-99 and radiothallium-201 are explained, as well as the relationship between effective, biological and physical half-lives, and the physico-chemical and pharmacological properties of each radiotracer. This chapter describes the principle of 99mTc MIBI and 99mTc-labelled tetrofosmin scintigraphy, and radiopharmaceuticals used to diagnose or localize myocardial infarction or myocardial ischemia. Myocardial 99mTc MIBI scintigraphy, coupled with pharmacological stimulation sensitized by Dipyridamole (Persantine®), is also described. Following on from this development, the principle of lung ventilation scintigraphy using Technetium-99m-labeled diethylenetriamine pentaacetic acid (DTPA), denoted as [99mTc]-DTPA, and the principle of lung perfusion scintigraphy using a radiotracer consisting of 99mTc-labeled human macro-albumin aggregates (MAA), denoted as 99mTc-MAA, are studied. The study then focuses on the principle of brain perfusion scintigraphy with the radiopharmaceuticals 99mTc-HMPAO (99mTc-hexamethylpropylene-amine-oxime) and 99mTc-ECD (99mTc-ethylenediyl bis-L-cysteine-diethyl-ester), which are used for the accurate diagnosis of cognitive disorders, strokes and epilepsy. The principle of 201Tl myocardial scintigraphy, used without a vector to assess coronary perfusion, is then studied. Next, the procedure for myocardial perfusion scintigraphy is described in detail, consisting of an exercise test on a bicycle (cycle ergometer) or a treadmill, or a stress test. Following on from this, the principle of bone scintigraphy using 99mTc-labeled biphosphonate carrier molecules (BPs), including 99mTc-methyl diphosphonate (99mTc-MDP) is explored. Finally, we describe the principle of static renal scintigraphy using the radiopharmaceutical 99mTc-DMSA (99mTc-dimercapto succinic acid) to assess kidney morphology, the principle of dynamic renal scintigraphy using 99mTc-MAG3 (99mTcmercapto acetyl triglycine) to assess kidney function and the principle of gastric scintigraphy based on the use of a standardized low-fat meal consisting of two eggs labeled with 99mTc-radiolabeled colloidal rhenium sulfide.

Chapter 3 is dedicated to the study of the radioisotopes fluorine-18, metastable krypton-81 and iodine-123, 125 and 131 used in nuclear medicine. It begins with a study of the physico-chemical and pharmacological properties of the radiopharmaceutical 2-deoxy-2-[18F]fluoro-D-glucose or 18FDG, the most widely used PET radiopharmaceutical. The process of obtaining radiofluorine-18 via the reactions 20Ne (d, α) 18F and 18O (p, n)18F, the radiofluorine-18 decay scheme, the 18FDG synthesis process, the principle of 18FDG scintigraphy and the mechanism of 18F excretion from the body are presented. Next, the physico-chemical and pharmacological properties of metastable krypton-81 (81mKr) are described, along with the 81mKr tracer production chain using the 81Rb/81mKr generator and the principles of 81mKr ventilation and lung perfusion scintigraphy used without a carrier as a complement to the 99mTc-MAA perfusion test. Finally, after describing the clearance mechanism of the 81mKr tracer, the physico-chemical and pharmacological properties of [123I] MIBG and [123I] Ioflupane radiopharmaceuticals used in SPECT imaging for the functional study of the thyroid gland are discussed. The usefulness of iodine, the production chain of the radiotracer 123l via generators 127I (p, 5n) 123Xe, 121Sb (α, 2 n) 123I, 122Te (d, n) 123I and 122Te (α, 3n) 123Xe, the main emissions of the radiotracer 123I, the principle of iodine-123 scintigraphy and its excretion from the body are presented. The physico-chemical and pharmacological properties of radioiodine-131 used in radiotherapy for the treatment of thyroid cancer or metastases, hyperthyroidism and goiter are then studied. This study begins with a description of the 131I radiotracer production chain via the nuclear reactions 130Te (n, γ) 131mTe and 130Te (n, γ) 131gTe, the main emissions of iodine-131, the principle of iodine-131 scintigraphy and its excretion mechanism. Then, the concepts of aerosol therapy, nebulization systems, aerosol generators and median mass aerodynamic diameter (MMAD) are defined. These definitions are rounded off with a description of aerosol deposition phenomena according to their MMAD. This is followed by a presentation of the prostate in the urinary tract and prostate diseases such as adenoma, prostatitis and cancer. These conditions are studied in detail, presenting their causes, risk factors, symptoms, diagnosis and treatment. The main treatment modalities for prostate cancer are then described. The special case of prostate brachytherapy using iodine-125 implants is examined in detail. The study begins with a description of the radioiodine-125 decay diagram, the brachytherapy modes of low-dose-rate (LDR), high-dose-rate (HDR) and pulsed-dose-rate (PDR) brachytherapy, and the procedure for brachytherapy with iodine-125 implants. Prostate chemotherapy is then briefly described.

Chapter 3 concludes with two appendices, shown in sections 3.8.1 and 3.8.2. The first appendix provides general information on strokes....