39. NUCLEAR MEDICINE Flashcards
(40 cards)
1
Q
- What does Nuclear Medicine consist of?
A
- it consists of a range of diagnostic and therapeutic
procedures
2
Q
- What do these diagnostic and therapeutic procedures make sure of?
A
- Radioisotopes
3
Q
- Why do they make use of Radioisotopes?
A
- these can penetrate tissue
- they can be detected by the outside body
- their distribution throughout the body can be
determined
4
Q
- When can we use Beta (β) Particle emitters?
A
- when the diagnostic test involves measuring samples
- these are taken from a patient
5
Q
- What kind of particle emission is more desirable when we are dealing with therapeutic work?
A
- the emission of Beta Particles
6
Q
- List 2 reasons as to why Beta Particles are preferred?
A
- They have a short range in tissue
- They an deliver high radiation doses
(this is due to the location of the radioisotope)
7
Q
- What do we use Radio-iodine (I¹³³) for?
A
- Thyroid Gland Treatments
8
Q
- What can be said about the absorption of Gamma Rays by the Human Body?
A
- they are extremely strong
- these rays do not get absorbed by the human body
- they simply pass through
9
Q
- What can be said about the absorption of Beta Rays by the Human Body?
A
- they are absorbed in the dermis
10
Q
- What can be said about the absorption of Alpha Rays by the Human Body?
A
- they are absorbed in the dermis
11
Q
- Who discovered natural radioactivity?
A
- Henri Becquerel
- he did this in 1896
12
Q
- What did Henri Becquerel explain?
A
- he explained the macroscopic kinetics of Radioactive
decay
13
Q
- Name the scientists that paved the way of Nuclear Medicine?
A
- Marie Sklodowska-Curie
- Pierre Curie
- Ernest Rutherford
- Frederick Soddy
14
Q
- How long did it take for the radioactive decay modes to be fully understood?
A
- several decades
15
Q
- Where can radioactive nuclides occur in?
A
THEY CAN OCCUR IN:
- nature
- they can be man made
16
Q
- What kind of stability do Radioactive Nuclides have?
A
- they are unstable
- they do not have the same number of protons and
neutrons - they try to reach more stable configurations
17
Q
- How do the Radioactive Nuclides reach more stable nuclear configurations?
A
- they do this through various processes of spontaneous
radioactive decay
18
Q
- List the 6 main categories of Radioactive Decay?
A
- Alpha (⍺) Decay
- Beta (β) Decay
- Gamma (y) Decay
- and Internal Conversion (IC) - Spontaneous Fission (SF)
- Proton Emission (PE) Decay
- Neutron Emission (NE) Decay
19
Q
- What usually accompanies Nuclear Transformations?
A
- the emission of energetic particles
20
Q
- There are many decay modes in which these energetic particles are released.
Name the first 6.
A
- Alpha (⍺) particles
- this happens through Alpha Decay - Electrons in Beta (β) - Decay
- Positrons in Beta (β) + Decay
- Neutrinos in Beta (β) + Decay
- Anti-neutrinos in Beta (β) - Decay
- Gamma (y) rays in Gamma (y) Decay
- these rays are electromagnetic
- they are similar to X-Rays
- they have more energy
21
Q
- There are many decay modes in which these energetic particles are released.
Name the next 4.
A
- Atomic Orbital Electrons in Internal Conversion (IC)
- Neutrons in Spontaneous Fission
- and in Neuton Emission Decay - Heavier nuclei in Spontaneous Fission
- Protons in Proton Emission
22
Q
- What is an Alpha Particle?
A
- it is a high energy Helium nuclei
- it consists of two protons
- it consists of two neutrons
23
Q
- What is a Beta Particle?
A
- these are high energy electrons
24
Q
- What is a Positron?
A
- these are particles with the same mass as an electron
- they have 1 unit of positive charge
25
25. What is a Proton?
- these are nuclei of Hydrogen atoms
26
26. What is a Neutron?
- these are particles with a mass that is approximately
equal to that of a proton
- but it has no charge
27
27. What is a Gamma Ray?
- these is very high energy electromagnetic radiation
28
28. There are specific physical quantities that must be conserved in each nuclear transformation.
List all 5 of the most important ones.
1. Total Energy
2. Atomic Number
(Proton Number)
3. Momentum
4. Charge
5. Atomic Mass Number
(Number of nucleons)
29
29. How can Nuclear Stability be achieved in low
atomic (Z) elements?
NUCLEAR STABILITY IS ACHIEVED:
- when the number of neutrons (N) is approximately
equal to the number of protons (Z)
30
30. What happens to the ratio of Neutrons to Protons
(N/Z) as the atomic number increases?
- the N/Z ratio increases from 1
- to about 1.5
31
31. What happens when a nucleus has a N/Z that is too high for Nuclear Stability?
- there is an excess number of neutrons present
- a direct emission of a neutron is possible
- this is called Neutron Rich
32
32. What happens when a Nucleus is Neutron rich?
- it decays through a conversion
- this conversion is of a neutron into a proton
THIS CONVERSION EMITS:
- an electron
- an anti-neutrino
NB:
- this process is known as Beta (β) - Decay
33
33. What are some similarities between Neutrinos and Anti-Neutrinos?
- they are the same sub-particles
- they have no mass
- they have no charge
34
34. What is the difference between Neutrinos and Anti-Neutrinos?
- they have different spin
- this maintains angular momentum during Beta - Decay
35
35. What happens when the nucleus has a N/Z ratio that is too low for Nuclear Stability?
- there is an excess number of Protons
- this is known as proton Rich
36
36. What happens when the Nucleus is Proton Rich?
- it decays through a conversion
- this conversion is of a proton into a neutron
THIS EMITS:
- a positron
- a neutrino
NB:
- this process is called Beta (β) + Decay
37
37. If a nucleus does not undergo Beta (B) + Decay, what other process can is partake in?
- the nucleus may capture an orbital electron
- it transforms a proton into a neutron
- it emits a neutrino
THIS PROCESS IS KNOWN AS:
- Electron Capture
38
38. What other method is there, is the nucleus does not undergo Beta (B) + Decay nor Electron Capture?
- the direct emission of a proton
- this is less likely
UNLESS:
- the nuclear imbalance is very high
39
39. Does this diagram make sense?
- yes
40
40. Does this diagram make sense?
- yes
