1st Class
This document was uploaded by user and they confirmed that they have the permission to share it. If you are author or own the copyright of this book, please report to us by using this DMCA report form. Report DMCA
Overview
Download & View 1st Class as PDF for free.
More details
- Words: 3,191
- Pages: 61
Nuclear Medicine
核医学 12/01/09
1
12/01/09
2
12/01/09
3
12/01/09
4
甲状腺显像
Thyroid Imaging
12/01/09
ectopia
5
Nuclear Medicine 核医学 郑州大学第一附属医院核医学科 Department of Nuclear Medicine, First Affiliated Hospital, Zhengzhou University
韩星敏 Han xingmin 12/01/09
6
Chapter 1
Introduction 12/01/09
7
1. What is Nuclear Medicine?
Nuclear medicine is a medical specialty which uses unique,safe,painless,and costeffective techniques both to diagnose and treat disease.
12/01/09
8
12/01/09
9
12/01/09
10
What is Nuclear Medicine?
Nuclear medicine imaging is unique in that it documents organ function and structure, in contrast to diagnostic radiology, which is based upon anatomy. Nuclear medicine imaging procedures often identify abnormalities very early in the progression of a disease -long before some medical problems are apparent with other diagnostic tests.
This early detection allows a disease to be treated early in its course when there may be a more successful prognosis.
12/01/09
11
12/01/09
12
12/01/09
13
12/01/09
14
12/01/09
15
2. Division of Nuclear Medicine
clinical nuclear medicine may be divided into two divisions:
the 1st division is In Vivo Study Another division is In Vitro testing (assay)
12/01/09
16
In Vivo Diagnosis Therapy Nuclide Imaging Measurement of Function
In vivo procedures are when trace amounts of radiopharmaceuticals are given directly to a patient. The largest division can be described as diagnostic procedures, such as, nuclide imaging, in which a suitable chemical form is administered to the patient and the distribution of radioactivity in the body is determined by an external detector e.g. liver scan, brain scan for the detection of a tumor, whole body imaging skeletal survey for the detection of metastases.
12/01/09
17
12/01/09
18
12/01/09
19
12/01/09
20
12/01/09
21
甲状腺显像
Thyroid Imaging
12/01/09
ectopia
22
In Vivo Study many synonyms imaging include
for
radionuclide
nuclear imaging, isotope imaging, nuclear medicine imaging, gamma scintigraphy, nuclear scanning, nuclear medicine scanning, isotope scanning, radionuclide scanning.
12/01/09
23
In Vivo Study
Today, nuclear medicine offers procedures that are helpful to a broad span of medical specialties, from pediatrics to cardiology to psychiatry. There are nearly one hundred different nuclear medicine imaging procedures available and not a major organ system which is not imaged by nuclear medicine.
12/01/09
24
In Vivo Study
Although nuclear medicine is commonly used for diagnostic purposes, it also has valuable therapeutic applications such as treatment of
12/01/09
hyperthyroidism thyroid cancer blood imbalances and pain relief from certain types of bone cancer
25
In Vitro
in-vitro procedures are done in test tubes Radioimmunoassay(RIA) is a special type of invitro procedure which combines the use of radiochemicals and antibodies to measure the levels of hormones, vitamins, drugs and other biological substances in a patient`s blood. AFP(alpha fetoprotein) 甲胎蛋白 CEA(carcino-embryonic antigen) 癌胚抗原 T3(triiodothyronine) 三碘甲腺原氨酸 T4(thyroxine), 甲状腺素
12/01/09
26
3. Safety of Nuclear Medicine
Nuclear medicine procedures are among the safest diagnostic imaging exams available. A patient only receives an extremely small amount of a radiopharmaceutical, just enough to provide sufficient diagnostic information. In fact, the amount of radiation from a nuclear medicine procedure is comparable to, or often times less than, that of a diagnostic x-ray.
12/01/09
27
4. The History Of Nuclear Medicine
Nuclear medicine has a complex and multifaceted heritage. Its origins stem from many scientific discoveries, most notably
12/01/09
the discovery of x-rays in 1895 , the discovery of mysterious "rays" from uranium by Henri Becquerel in 1896 and the discovery of "artificial radioactivity" in 1934 .
28
The History Of Nuclear Medicine
The first clinical use of "artificial radioactivity" was carried out in 1937 for the treatment of a patient with leukemia at the University of California at Berkeley. A landmark event for nuclear medicine occurred in 1946 when a thyroid cancer patient's treatment with radioactive iodine caused complete disappearance of the spread of the patient's cancer. This has been considered by some as the true beginning of nuclear medicine.
12/01/09
29
12/01/09
30
The History Of Nuclear Medicine
Wide-spread clinical use of nuclear medicine, however, did not start until the early 1950s.
The value of radioactive iodine became apparent as its use increased to measure the function of the thyroid and to diagnose thyroid disease. Simultaneously, more and more physicians begin to use "nuclear medicine" for the treatment of patients with hyperthyroidism. The concept of nuclear medicine was a dramatic breakthrough for diagnostic medicine. Moreover, the ability to treat a disease with radiopharmaceuticals and to record and make a "picture" of the form and structure of an organ was invaluable.
12/01/09
31
The History Of Nuclear Medicine
In the mid-sixties and the years that followed, the growth of nuclear medicine as a specialty discipline was phenomenal. The 1970s brought the visualization of most other organs of the body with nuclear medicine, including liver and spleen scanning, brain tumor localization, and studies of the gastrointestinal track. The 1980s provided the use of radiopharmaceuticals for such critical diagnoses as heart disease and the development of cutting-edge nuclear medicine cameras and computers.
12/01/09
32
The History Of Nuclear Medicine
Today, there are nearly 100 different nuclear medicine procedures that uniquely provide information about virtually every major organ system within the body. Nuclear medicine is an integral part of patient care, and an important diagnostic and therapeutic specialty in the armamentarium of medical science.
12/01/09
33
5. Nuclear Medicine, X-Rays , CT, and MRI
Nuclear medicine began approximately 60 years ago and has evolved into a major medical specialty for both diagnosis and therapy of serious disease. More than 3,900 hospital-based nuclear medicine departments in the United States perform over 10 million nuclear medicine imaging and therapeutic procedures each year (2564/year.department, 8~10/day.department). Despite its integral role in patient care, nuclear medicine is still often confused with other imaging procedures, including general radiology, CT, and MRI.
12/01/09
34
Nuclear Medicine, X-Rays, CT, and MRI
General Radiology The image, or a x-ray film, is produced when a small amount of radiation passes through the body to expose sensitive film on the other side. The ability of x-rays to penetrate tissues and bones depends on the tissue's composition and mass. The difference between these two elements creates the images.
Computed tomography or CT, shows organs of interest at selected levels of the body. They are visual equivalent of bloodless slices of anatomy, with each scan being a single slice. Like CT, MRI produces images, which are the visual equivalent of a slice of anatomy.
12/01/09
35
Nuclear Medicine, X-Rays, CT, and MRI
Nuclear medicine studies document organ function and structure, in contrast to conventional radiology, which creates images based upon anatomy. Many of the nuclear medicine studies can measure the degree of function present in an organ, often times eliminating the need for surgery. Moreover, nuclear medicine procedures often provide important information that allows the physician to detect and treat a disease early in its course when there may be more success. It is nuclear medicine that can best be used to study the function of a damaged heart or restriction of blood flow to parts of the brain. The liver, kidneys, thyroid gland, and many other organs are similarly imaged.
12/01/09
36
12/01/09
37
Important Dates in the History of Nuclear Medicine 1896 Henri Becquerel discovered mysterious "rays" from uranium. 1897 Marie Curie named the mysterious rays "radioactivity." 1901 Henri Alexandre Danlos and Eugene Bloch placed radium in contact with a tuberculous skin lesion. 1903 Alexander Graham Bell suggested placing sources containing radium in or near tumors. 1913 Frederick Proescher published the first study on the intravenous injection of radium for therapy of various diseases. 1924 Georg de Hevesy, J.A. Christiansen and Sven Lomholt performed the first radiotracer (lead-210 and bismuth-210) studies in animals. 12/01/09
38
Important Dates in the History of Nuclear Medicine 1932 Ernest O. Lawrence and M. Stanley Livingston published the first article on "the production of high speed light ions without the use of high voltages." It was a milestone in the production of usable quantities of radionuclides. 1936 John H. Lawrence, the brother of Ernest, made the first clinical therapeutic application of an artificial radionuclide when he used phosphorus-32 to treat leukemia. 1937 John Livingood, Fred Fairbrother and Glenn Seaborg discovered iron-59. 1938 John Livingood and Glenn Seaborg discovered iodine-131 and cobalt-60. 1939 Emilio Segre and Glenn Seaborg discovered technetium-99m. 1940 The Rockefeller Foundation funded the first cyclotron dedicated for biomedical radioisotope production at Washington University in St. Louis. 12/01/09 39
Important Dates in the History of Nuclear Medicine 1946 Samuel M. Seidlin, Leo D. Marinelli and Eleanor Oshry treated a patient with thyroid cancer with iodine-131, an "atomic cocktail." 1947 Benedict Cassen used radioiodine to determine whether a thyroid nodule accumulates iodine, helping to differentiate benign from malignant nodules. 1948 Abbott Laboratories began distribution of radioisotopes. 1950 The U.S. Food and Drug Administration (FDA) approved sodium iodide 1-131 for use with thyroid patients. It was the first FDA-approved radiopharmaceutical.
12/01/09
40
Important Dates in the History of Nuclear Medicine 1951 K.R. Crispell and John P. Storaasli used iodine-131 labeled human serum albumin (RISA) for imaging the blood pool within the heart. 1953 Gordon Brownell and H.H. Sweet built a positron detector based on the detection of annihilation photons by means of coincidence counting. 1954 David Kuhl invented a photorecording system for radionuclide scanning. This development moved nuclear medicine further in the direction of radiology. 1955 Rex Huff measured the cardiac output in man using iodine-131 human serum albumin. 1958 Hal Anger invented the "scintillation camera," an imaging device that made it possible to conduct dynamic studies. 1960 Louis G. Stang, Jr., and Powell (Jim) Richards advertised technetium-99m and other generators for sale by Brookhaven National Laboratory. Technetium-99m had not yet been used 12/01/09 41 in
Important Dates in the History of Nuclear Medicine 1962 David Kuhl introduced emission reconstruction tomography. This method later became known as SPECT and PET. It was extended in radiology to transmission X-ray scanning, known as CT. 1963 The FDA exempted the "new drug" requirements for radiopharmaceuticals regulated by the Atomic Energy Commission. 1963 Henry Wagner first used radiolabeled albumin aggregates for imaging lung perfusion in normal persons and patients with pulmonary embolism. 1969 C.L. Edwards reported the accumulation of gallium-67 in cancer. 1970 The FDA announced that it would gradually withdraw the exemption granted to radiopharmaceuticals and start regulating them as drugs. The change would be completed by 12/01/09 42 Jan. 20, 1977.
Important Dates in the History of Nuclear Medicine
.
1971 The American Medical Association officially nuclear medicine as a medical speciality.
recognized
1973 H. William Strauss myocardial scan.
stress-test
introduced
the
exercise
1976 John Keyes developed the first general purpose single photo emission computed tomography (SPECT) camera. Ronald Jaszczak developed the first dedicated head SPECT camera. 1978 David Goldenberg used radiolabeled antibodies to image tumors in humans.
12/01/09
43
Important Dates in the History of Nuclear Medicine 1981 J.P. Mach used radiolabeled monoclonal antibodies for tumor imaging. 1982 Steve Larson and Jeff Carrasquillo treated cancer patients with malignant melanoma using iodine-131 labeled monoclonal antibodies. 1989 The FDA approved the first positron radiopharmaceutical (rubidium-82) for myocardial perfusion imaging. 1992 The FDA approved the first monoclonal radiopharmaceutical for tumor imaging.
12/01/09
antibody
44
Chapter 2 Basic Physics for Nuclear Medicine 12/01/09
45
Concepts
Radioactivity is the spontaneous disintegration (decay) of the nucleus of a radioactive atom. In the decay event, several kinds of radiation may be emitted from the nucleus. The nucleus is the central, heavy part of the atom. The nucleus contains the protons and neutrons (collectively called nucleons) of the atom. In one of the models of the atom the nucleus is surrounded by electrons which whirl around the nucleus.
12/01/09
46
Protons are positively charged particles. Their positive charge is equal in magnitude and opposite to the charge of an electron.The element the atom belongs to is determined by the number of protons in the nucleus. For instance, atoms with one proton are called hydrogen, those with two are helium atoms, and three protons are in the nuclei of lithium atoms. Neutrons, the other nuclear component, also weigh one atomic mass unit, are electrically neutral.
12/01/09
47
By convention, a shorthand notation has been developed to uniquely describe or define specific atoms. The notation is as follows:
A
X is the symbol for the element Z is the number of protons N is the number of neutrons A is the total number of neutrons and protons
Z
X
N
The number of neutrons plus the number of protons is the mass number of an atom.
12/01/09
Thus, in 131 I, the 131 is the mass number, and refers to the number of nucleons, 53 protons and 78 neutrons.
48
isotopes Atoms with the same number of protons but differing numbers of neutrons are called isotopes of that element. 131 I, 123 I 125 I 127 I Nuclide : A nuclide is a species of atom with a particular combination of atomic number (z), atomic mass number (A) and in certain cases of the nuclear energy state. Radionuclide is simply an unstable nuclide or nuclear species that undergoes radioactive decay.
12/01/09
49
Isomer: An isomer is a species of atom with the same number of protons and same number of neutrons but differing cases the nuclear energy state. 99m Tc, 99Tc m denotes a metastable • or prolonged intermediate state in the decay of molybdenum-99 to technetium-99
Radiation: Energy emitted by atoms undergoing internal change, transferred through space or matter, is called radiation.
12/01/09
50
radioactivity is quantitatively measured as the
number of atoms that disintegrate per unit time. 2 systems for expressing radioactivity
Curie (Ci), which was named in honor of Marie Curie This unit was based on the disintegration rate of 1 gram of radium.
1Ci = 3.7×1010 dps
Becquerel (Bq) , which was named in honor of Henri Becquerel
1Bq = 1 dps 1Ci =3.7×1010 Bq= 37×109 Bq=37 GBq 1mCi =3.7×107 Bq= 37×106 Bq=37 MBq 1μCi =3.7×104 Bq= 37×103Bq= 37 KBq
12/01/09
51
half-life
Physical half-life (T 1/2 ) , which is defined as the time required for one-half of the atoms in a group of radioactive atoms to decay. effective half-life (T1/2 )eff, The real measure of radiation exposure is related to the effective half-life ((T1/2 )eff) of a radioisotope in the body. The (T1/2 )eff is given by the formula (T1/2 )eff=(T1/2 )p×(T1/2 )b/[(T1/2 )p+(T1/2 )b]
(T1/2 )p is the physical half-life, and
(T1/2 )b is the biological half-life
12/01/09
biological clearance of the radionuclide from a particular tissue or organ system 52
energy of radioactive decay
The unit used to describe the energy of radioactive decay and of atomic radiation is the electron volt （ eV ） , usually expressed in multiples of a thousand (kiloelectron volts, keV) or millions (megaelectron volts, MeV).
12/01/09
53
Radioactive decay and emissions
The process of radioactive decay produces radiations which can be of several types. There are three basic kinds of radiations, which were named for the first three letters of the Greek alphabet: alpha, beta, and gamma radiation.
12/01/09
54
Radioactive decay and emissions
Alpha decay is the emission of a helium nucleus by a radioactive atom.
Although the alpha particles are emitted with considerable energy, their range in tissue is of the order of a few micrometers, which means that internally-deposited alpha emitters cannot be detected outside the patient. This short range also means that alpha particles produce considerable biological damage when decay occurs in tissues: all of the alpha decay energy is locally deposited.
12/01/09
55
Radioactive decay and emissions
Beta particles are really high-speed electrons emitted by certain radioactive isotopes, such as iodine-131. I, for instance, emits most of its beta particles in tissue is only a few millimeters, so external detection of internally-deposited beta particle emitters is almost impossible.
131
The biological damage to tissues is also high, as indicated by the efficacy of thyroid ablation with 131I.
12/01/09
56
Radioactive decay and emissions
positron
A unique kind of beta particle occurs in certain man-made radioisotopes: instead of emitting an electron, these radioisotopes (18 F is a typical example) produce a positively-charged beta particle (positron) on the decay process. The positron is physically identical to the electron except for its charge, the positron is an antiparticle, and when it slows down, it combines with a normal electron in a process called annihilation, which destroys both the electron and the positron and produces two energetic photons, each with 511KeV.These photons are similar to gamma rays, and their energy is so unique that it is called annihilation radiation. For PET imaging
12/01/09
57
Radioactive decay and emissions
Gamma rays are really electromagnetic radiation, radiation with properties similar to light-rays, and Xrays.
In fact, gamma radiation is physically indistinguishable from X-rays once the radiation has left the source. Like X-rays, gamma rays are very penetrating, and easily pass through tissue. In nuclear medicine radioisotopes which emit gamma rays are administered to the patient. The radioisotope is incorporated in a radiopharmaceutical designed to produce localization in a particular organ. The gamma rays emitted by the decaying radioisotopes in the organ are detected externally with extremely sensitive detector. For SPECT imaging
12/01/09
58
Radioactive decay and emissions
Some radioisotope produce both gamma and beta radiation when they decay. 131I is a good example: 131 I emits beta particles with an average energy of about 200 KeV （ kiloelectron volts ） , and several gamma rays, the most important of which for nuclear medicine imaging is the gamma ray of 364 KeV.
12/01/09
59
Radioactive decay and emissions
β-particles and α-particles, also forms of ionizing radiation, may contribute to radiation dose in medical procedures, but, are not useful for imaging, mainly because they travel distances of only a few millimeters in tissue. Medical diagnostic imaging has used chiefly ionizing radiation in the form of x-rays and γ rays. The most widely used radioisotope in nuclear medicine is technetium-99m. The “m” in “99m” refers to a metastable state of the nucleus which decays with a very short half-life (6h) to the more stable 99Tc by emitting a gamma ray of 140 KeV.
12/01/09
60
Home work 1.
How many portions does nuclear medicine can be divided into?What are the synonyms for radionuclide imaging? Interpret definition: isotopes of the element, nuclide, isomer, radiation, activity, half-life, and electron volt. 2. How many kinds of radiation? Which particle can be detected by SPECT? What is the most widely used radioisotope in nuclear medicine? Which particle can be used for PET imaging? Which particle can be used to treat disease?
12/01/09
61
核医学 12/01/09
1
12/01/09
2
12/01/09
3
12/01/09
4
甲状腺显像
Thyroid Imaging
12/01/09
ectopia
5
Nuclear Medicine 核医学 郑州大学第一附属医院核医学科 Department of Nuclear Medicine, First Affiliated Hospital, Zhengzhou University
韩星敏 Han xingmin 12/01/09
6
Chapter 1
Introduction 12/01/09
7
1. What is Nuclear Medicine?
Nuclear medicine is a medical specialty which uses unique,safe,painless,and costeffective techniques both to diagnose and treat disease.
12/01/09
8
12/01/09
9
12/01/09
10
What is Nuclear Medicine?
Nuclear medicine imaging is unique in that it documents organ function and structure, in contrast to diagnostic radiology, which is based upon anatomy. Nuclear medicine imaging procedures often identify abnormalities very early in the progression of a disease -long before some medical problems are apparent with other diagnostic tests.
This early detection allows a disease to be treated early in its course when there may be a more successful prognosis.
12/01/09
11
12/01/09
12
12/01/09
13
12/01/09
14
12/01/09
15
2. Division of Nuclear Medicine
clinical nuclear medicine may be divided into two divisions:
the 1st division is In Vivo Study Another division is In Vitro testing (assay)
12/01/09
16
In Vivo Diagnosis Therapy Nuclide Imaging Measurement of Function
In vivo procedures are when trace amounts of radiopharmaceuticals are given directly to a patient. The largest division can be described as diagnostic procedures, such as, nuclide imaging, in which a suitable chemical form is administered to the patient and the distribution of radioactivity in the body is determined by an external detector e.g. liver scan, brain scan for the detection of a tumor, whole body imaging skeletal survey for the detection of metastases.
12/01/09
17
12/01/09
18
12/01/09
19
12/01/09
20
12/01/09
21
甲状腺显像
Thyroid Imaging
12/01/09
ectopia
22
In Vivo Study many synonyms imaging include
for
radionuclide
nuclear imaging, isotope imaging, nuclear medicine imaging, gamma scintigraphy, nuclear scanning, nuclear medicine scanning, isotope scanning, radionuclide scanning.
12/01/09
23
In Vivo Study
Today, nuclear medicine offers procedures that are helpful to a broad span of medical specialties, from pediatrics to cardiology to psychiatry. There are nearly one hundred different nuclear medicine imaging procedures available and not a major organ system which is not imaged by nuclear medicine.
12/01/09
24
In Vivo Study
Although nuclear medicine is commonly used for diagnostic purposes, it also has valuable therapeutic applications such as treatment of
12/01/09
hyperthyroidism thyroid cancer blood imbalances and pain relief from certain types of bone cancer
25
In Vitro
in-vitro procedures are done in test tubes Radioimmunoassay(RIA) is a special type of invitro procedure which combines the use of radiochemicals and antibodies to measure the levels of hormones, vitamins, drugs and other biological substances in a patient`s blood. AFP(alpha fetoprotein) 甲胎蛋白 CEA(carcino-embryonic antigen) 癌胚抗原 T3(triiodothyronine) 三碘甲腺原氨酸 T4(thyroxine), 甲状腺素
12/01/09
26
3. Safety of Nuclear Medicine
Nuclear medicine procedures are among the safest diagnostic imaging exams available. A patient only receives an extremely small amount of a radiopharmaceutical, just enough to provide sufficient diagnostic information. In fact, the amount of radiation from a nuclear medicine procedure is comparable to, or often times less than, that of a diagnostic x-ray.
12/01/09
27
4. The History Of Nuclear Medicine
Nuclear medicine has a complex and multifaceted heritage. Its origins stem from many scientific discoveries, most notably
12/01/09
the discovery of x-rays in 1895 , the discovery of mysterious "rays" from uranium by Henri Becquerel in 1896 and the discovery of "artificial radioactivity" in 1934 .
28
The History Of Nuclear Medicine
The first clinical use of "artificial radioactivity" was carried out in 1937 for the treatment of a patient with leukemia at the University of California at Berkeley. A landmark event for nuclear medicine occurred in 1946 when a thyroid cancer patient's treatment with radioactive iodine caused complete disappearance of the spread of the patient's cancer. This has been considered by some as the true beginning of nuclear medicine.
12/01/09
29
12/01/09
30
The History Of Nuclear Medicine
Wide-spread clinical use of nuclear medicine, however, did not start until the early 1950s.
The value of radioactive iodine became apparent as its use increased to measure the function of the thyroid and to diagnose thyroid disease. Simultaneously, more and more physicians begin to use "nuclear medicine" for the treatment of patients with hyperthyroidism. The concept of nuclear medicine was a dramatic breakthrough for diagnostic medicine. Moreover, the ability to treat a disease with radiopharmaceuticals and to record and make a "picture" of the form and structure of an organ was invaluable.
12/01/09
31
The History Of Nuclear Medicine
In the mid-sixties and the years that followed, the growth of nuclear medicine as a specialty discipline was phenomenal. The 1970s brought the visualization of most other organs of the body with nuclear medicine, including liver and spleen scanning, brain tumor localization, and studies of the gastrointestinal track. The 1980s provided the use of radiopharmaceuticals for such critical diagnoses as heart disease and the development of cutting-edge nuclear medicine cameras and computers.
12/01/09
32
The History Of Nuclear Medicine
Today, there are nearly 100 different nuclear medicine procedures that uniquely provide information about virtually every major organ system within the body. Nuclear medicine is an integral part of patient care, and an important diagnostic and therapeutic specialty in the armamentarium of medical science.
12/01/09
33
5. Nuclear Medicine, X-Rays , CT, and MRI
Nuclear medicine began approximately 60 years ago and has evolved into a major medical specialty for both diagnosis and therapy of serious disease. More than 3,900 hospital-based nuclear medicine departments in the United States perform over 10 million nuclear medicine imaging and therapeutic procedures each year (2564/year.department, 8~10/day.department). Despite its integral role in patient care, nuclear medicine is still often confused with other imaging procedures, including general radiology, CT, and MRI.
12/01/09
34
Nuclear Medicine, X-Rays, CT, and MRI
General Radiology The image, or a x-ray film, is produced when a small amount of radiation passes through the body to expose sensitive film on the other side. The ability of x-rays to penetrate tissues and bones depends on the tissue's composition and mass. The difference between these two elements creates the images.
Computed tomography or CT, shows organs of interest at selected levels of the body. They are visual equivalent of bloodless slices of anatomy, with each scan being a single slice. Like CT, MRI produces images, which are the visual equivalent of a slice of anatomy.
12/01/09
35
Nuclear Medicine, X-Rays, CT, and MRI
Nuclear medicine studies document organ function and structure, in contrast to conventional radiology, which creates images based upon anatomy. Many of the nuclear medicine studies can measure the degree of function present in an organ, often times eliminating the need for surgery. Moreover, nuclear medicine procedures often provide important information that allows the physician to detect and treat a disease early in its course when there may be more success. It is nuclear medicine that can best be used to study the function of a damaged heart or restriction of blood flow to parts of the brain. The liver, kidneys, thyroid gland, and many other organs are similarly imaged.
12/01/09
36
12/01/09
37
Important Dates in the History of Nuclear Medicine 1896 Henri Becquerel discovered mysterious "rays" from uranium. 1897 Marie Curie named the mysterious rays "radioactivity." 1901 Henri Alexandre Danlos and Eugene Bloch placed radium in contact with a tuberculous skin lesion. 1903 Alexander Graham Bell suggested placing sources containing radium in or near tumors. 1913 Frederick Proescher published the first study on the intravenous injection of radium for therapy of various diseases. 1924 Georg de Hevesy, J.A. Christiansen and Sven Lomholt performed the first radiotracer (lead-210 and bismuth-210) studies in animals. 12/01/09
38
Important Dates in the History of Nuclear Medicine 1932 Ernest O. Lawrence and M. Stanley Livingston published the first article on "the production of high speed light ions without the use of high voltages." It was a milestone in the production of usable quantities of radionuclides. 1936 John H. Lawrence, the brother of Ernest, made the first clinical therapeutic application of an artificial radionuclide when he used phosphorus-32 to treat leukemia. 1937 John Livingood, Fred Fairbrother and Glenn Seaborg discovered iron-59. 1938 John Livingood and Glenn Seaborg discovered iodine-131 and cobalt-60. 1939 Emilio Segre and Glenn Seaborg discovered technetium-99m. 1940 The Rockefeller Foundation funded the first cyclotron dedicated for biomedical radioisotope production at Washington University in St. Louis. 12/01/09 39
Important Dates in the History of Nuclear Medicine 1946 Samuel M. Seidlin, Leo D. Marinelli and Eleanor Oshry treated a patient with thyroid cancer with iodine-131, an "atomic cocktail." 1947 Benedict Cassen used radioiodine to determine whether a thyroid nodule accumulates iodine, helping to differentiate benign from malignant nodules. 1948 Abbott Laboratories began distribution of radioisotopes. 1950 The U.S. Food and Drug Administration (FDA) approved sodium iodide 1-131 for use with thyroid patients. It was the first FDA-approved radiopharmaceutical.
12/01/09
40
Important Dates in the History of Nuclear Medicine 1951 K.R. Crispell and John P. Storaasli used iodine-131 labeled human serum albumin (RISA) for imaging the blood pool within the heart. 1953 Gordon Brownell and H.H. Sweet built a positron detector based on the detection of annihilation photons by means of coincidence counting. 1954 David Kuhl invented a photorecording system for radionuclide scanning. This development moved nuclear medicine further in the direction of radiology. 1955 Rex Huff measured the cardiac output in man using iodine-131 human serum albumin. 1958 Hal Anger invented the "scintillation camera," an imaging device that made it possible to conduct dynamic studies. 1960 Louis G. Stang, Jr., and Powell (Jim) Richards advertised technetium-99m and other generators for sale by Brookhaven National Laboratory. Technetium-99m had not yet been used 12/01/09 41 in
Important Dates in the History of Nuclear Medicine 1962 David Kuhl introduced emission reconstruction tomography. This method later became known as SPECT and PET. It was extended in radiology to transmission X-ray scanning, known as CT. 1963 The FDA exempted the "new drug" requirements for radiopharmaceuticals regulated by the Atomic Energy Commission. 1963 Henry Wagner first used radiolabeled albumin aggregates for imaging lung perfusion in normal persons and patients with pulmonary embolism. 1969 C.L. Edwards reported the accumulation of gallium-67 in cancer. 1970 The FDA announced that it would gradually withdraw the exemption granted to radiopharmaceuticals and start regulating them as drugs. The change would be completed by 12/01/09 42 Jan. 20, 1977.
Important Dates in the History of Nuclear Medicine
.
1971 The American Medical Association officially nuclear medicine as a medical speciality.
recognized
1973 H. William Strauss myocardial scan.
stress-test
introduced
the
exercise
1976 John Keyes developed the first general purpose single photo emission computed tomography (SPECT) camera. Ronald Jaszczak developed the first dedicated head SPECT camera. 1978 David Goldenberg used radiolabeled antibodies to image tumors in humans.
12/01/09
43
Important Dates in the History of Nuclear Medicine 1981 J.P. Mach used radiolabeled monoclonal antibodies for tumor imaging. 1982 Steve Larson and Jeff Carrasquillo treated cancer patients with malignant melanoma using iodine-131 labeled monoclonal antibodies. 1989 The FDA approved the first positron radiopharmaceutical (rubidium-82) for myocardial perfusion imaging. 1992 The FDA approved the first monoclonal radiopharmaceutical for tumor imaging.
12/01/09
antibody
44
Chapter 2 Basic Physics for Nuclear Medicine 12/01/09
45
Concepts
Radioactivity is the spontaneous disintegration (decay) of the nucleus of a radioactive atom. In the decay event, several kinds of radiation may be emitted from the nucleus. The nucleus is the central, heavy part of the atom. The nucleus contains the protons and neutrons (collectively called nucleons) of the atom. In one of the models of the atom the nucleus is surrounded by electrons which whirl around the nucleus.
12/01/09
46
Protons are positively charged particles. Their positive charge is equal in magnitude and opposite to the charge of an electron.The element the atom belongs to is determined by the number of protons in the nucleus. For instance, atoms with one proton are called hydrogen, those with two are helium atoms, and three protons are in the nuclei of lithium atoms. Neutrons, the other nuclear component, also weigh one atomic mass unit, are electrically neutral.
12/01/09
47
By convention, a shorthand notation has been developed to uniquely describe or define specific atoms. The notation is as follows:
A
X is the symbol for the element Z is the number of protons N is the number of neutrons A is the total number of neutrons and protons
Z
X
N
The number of neutrons plus the number of protons is the mass number of an atom.
12/01/09
Thus, in 131 I, the 131 is the mass number, and refers to the number of nucleons, 53 protons and 78 neutrons.
48
isotopes Atoms with the same number of protons but differing numbers of neutrons are called isotopes of that element. 131 I, 123 I 125 I 127 I Nuclide : A nuclide is a species of atom with a particular combination of atomic number (z), atomic mass number (A) and in certain cases of the nuclear energy state. Radionuclide is simply an unstable nuclide or nuclear species that undergoes radioactive decay.
12/01/09
49
Isomer: An isomer is a species of atom with the same number of protons and same number of neutrons but differing cases the nuclear energy state. 99m Tc, 99Tc m denotes a metastable • or prolonged intermediate state in the decay of molybdenum-99 to technetium-99
Radiation: Energy emitted by atoms undergoing internal change, transferred through space or matter, is called radiation.
12/01/09
50
radioactivity is quantitatively measured as the
number of atoms that disintegrate per unit time. 2 systems for expressing radioactivity
Curie (Ci), which was named in honor of Marie Curie This unit was based on the disintegration rate of 1 gram of radium.
1Ci = 3.7×1010 dps
Becquerel (Bq) , which was named in honor of Henri Becquerel
1Bq = 1 dps 1Ci =3.7×1010 Bq= 37×109 Bq=37 GBq 1mCi =3.7×107 Bq= 37×106 Bq=37 MBq 1μCi =3.7×104 Bq= 37×103Bq= 37 KBq
12/01/09
51
half-life
Physical half-life (T 1/2 ) , which is defined as the time required for one-half of the atoms in a group of radioactive atoms to decay. effective half-life (T1/2 )eff, The real measure of radiation exposure is related to the effective half-life ((T1/2 )eff) of a radioisotope in the body. The (T1/2 )eff is given by the formula (T1/2 )eff=(T1/2 )p×(T1/2 )b/[(T1/2 )p+(T1/2 )b]
(T1/2 )p is the physical half-life, and
(T1/2 )b is the biological half-life
12/01/09
biological clearance of the radionuclide from a particular tissue or organ system 52
energy of radioactive decay
The unit used to describe the energy of radioactive decay and of atomic radiation is the electron volt （ eV ） , usually expressed in multiples of a thousand (kiloelectron volts, keV) or millions (megaelectron volts, MeV).
12/01/09
53
Radioactive decay and emissions
The process of radioactive decay produces radiations which can be of several types. There are three basic kinds of radiations, which were named for the first three letters of the Greek alphabet: alpha, beta, and gamma radiation.
12/01/09
54
Radioactive decay and emissions
Alpha decay is the emission of a helium nucleus by a radioactive atom.
Although the alpha particles are emitted with considerable energy, their range in tissue is of the order of a few micrometers, which means that internally-deposited alpha emitters cannot be detected outside the patient. This short range also means that alpha particles produce considerable biological damage when decay occurs in tissues: all of the alpha decay energy is locally deposited.
12/01/09
55
Radioactive decay and emissions
Beta particles are really high-speed electrons emitted by certain radioactive isotopes, such as iodine-131. I, for instance, emits most of its beta particles in tissue is only a few millimeters, so external detection of internally-deposited beta particle emitters is almost impossible.
131
The biological damage to tissues is also high, as indicated by the efficacy of thyroid ablation with 131I.
12/01/09
56
Radioactive decay and emissions
positron
A unique kind of beta particle occurs in certain man-made radioisotopes: instead of emitting an electron, these radioisotopes (18 F is a typical example) produce a positively-charged beta particle (positron) on the decay process. The positron is physically identical to the electron except for its charge, the positron is an antiparticle, and when it slows down, it combines with a normal electron in a process called annihilation, which destroys both the electron and the positron and produces two energetic photons, each with 511KeV.These photons are similar to gamma rays, and their energy is so unique that it is called annihilation radiation. For PET imaging
12/01/09
57
Radioactive decay and emissions
Gamma rays are really electromagnetic radiation, radiation with properties similar to light-rays, and Xrays.
In fact, gamma radiation is physically indistinguishable from X-rays once the radiation has left the source. Like X-rays, gamma rays are very penetrating, and easily pass through tissue. In nuclear medicine radioisotopes which emit gamma rays are administered to the patient. The radioisotope is incorporated in a radiopharmaceutical designed to produce localization in a particular organ. The gamma rays emitted by the decaying radioisotopes in the organ are detected externally with extremely sensitive detector. For SPECT imaging
12/01/09
58
Radioactive decay and emissions
Some radioisotope produce both gamma and beta radiation when they decay. 131I is a good example: 131 I emits beta particles with an average energy of about 200 KeV （ kiloelectron volts ） , and several gamma rays, the most important of which for nuclear medicine imaging is the gamma ray of 364 KeV.
12/01/09
59
Radioactive decay and emissions
β-particles and α-particles, also forms of ionizing radiation, may contribute to radiation dose in medical procedures, but, are not useful for imaging, mainly because they travel distances of only a few millimeters in tissue. Medical diagnostic imaging has used chiefly ionizing radiation in the form of x-rays and γ rays. The most widely used radioisotope in nuclear medicine is technetium-99m. The “m” in “99m” refers to a metastable state of the nucleus which decays with a very short half-life (6h) to the more stable 99Tc by emitting a gamma ray of 140 KeV.
12/01/09
60
Home work 1.
How many portions does nuclear medicine can be divided into?What are the synonyms for radionuclide imaging? Interpret definition: isotopes of the element, nuclide, isomer, radiation, activity, half-life, and electron volt. 2. How many kinds of radiation? Which particle can be detected by SPECT? What is the most widely used radioisotope in nuclear medicine? Which particle can be used for PET imaging? Which particle can be used to treat disease?
12/01/09
61
Related Documents
1st Class
July 2020 11
1st Class English
June 2020 12
Lesson_plan_5th Grade 1st Class
November 2019 15
Bd Academy 1st Class
November 2019 11
Paper Evs 1st Class
June 2020 13