Clinical Radiation Generators

Question 1

Machines that can generate x-rays at voltages up to 300 kVp.

Answer 1

Kilovoltage Therapy Units

Question 2

Used up to about 1950 and succeeded by Megavoltage units specifically the Cobalt 60 unit

Answer 2

Kilovoltage Therapy Units

Question 3

Useful in the treatment of skin cancer extending no more than about 1 cm below the surface

Answer 3

Kilovoltage Therapy Units

Question 4

Types of Kilovoltage Theray Units

Answer 4

Grenz Ray
Contact Therapy
Superficial Therapy
Deep Therapy Unit

Question 5

A german word means “border”

Answer 5

Grenz

Question 6

CHARACTERISTICS
• Very soft x-rays
• Operates at a potential below 20 kV
• Results to very low depth penetration

Answer 6

Grenz Rays

Question 7

CLINICAL APPLICATION:

• Dermatological use (penetrating nickel sensitive patient: supress allergic contact dermatitis)

Answer 7

Grenz Rays

Question 8

Its the names was delivered by the way the treatment unit actually came in contact with the patient

Answer 8

Contact therapy

Question 9

Contact therapy’s potential

Answer 9

40 to 50 kV

Question 10

Contact therapy’s tube current

Answer 10

2 mA

Question 11

Contact therapy’s SSD

Answer 11

2.0 cm or less

Question 12

Used to absorb the very soft component of the energy spectrum

Answer 12

A filter of 0.5 to 1.00 mm think Al

Question 13

Useful for tumors not deeper than 1.2 mm.

Used to treat superficial skin lesions

Answer 13

Contact therapy

Question 14

2 major types of Radiation Generators

Answer 14

1. Kilovoltage Therapy Units

2. Megavoltage Therapy Units

Question 15

Superficial therapy’s tube current

Answer 15

5 - 8 mA

Question 16

Superficial therapy’s SSD

Answer 16

15 - 20 cm

Question 17

Varying thickness (1-6 mm Al) of filtration is used

Answer 17

Superficial therapy

Question 18

Useul for tumors confined to about 5mm depth

Answer 18

Superficial therapy

Question 19

Deep therapy unit also called…

Answer 19

Orthovoltage

Question 20

Deep therapy unit’s potential

Answer 20

150 - 500 kV

Question 21

Deep therapy unit’s tube current

Answer 21

10-20 mA

Question 22

Deep therapy unit’s SSD

Answer 22

50 cm

Question 23

Useful for tumors within 2cm depth

Answer 23

Deep therapy unit

Question 24

Some disadvantages of kV units

Answer 24

Large skin dose
Poor depth dose distriction
Increased absorbed dose in bone
Increased scattering

Question 25

Radiotherapy equipments that deliver beams with high dose rate in the "multimillion volt" (1 MV or higher) range.

Answer 25

Megavolage therapy units (high-energy theraphy units)

Question 26

Telecurie Beam Units use _, _, _ as radioactive sources

Answer 26

Radium 226 Cobalt 60 Cesium 137

Question 27

__ rays are emitted from these sources as they undergo radioactive disintegration

Answer 27

Gamma

Question 28

Placed in contact with patient's skin for treatment of underlying skin lesions. This was the birth of "brachytherapy"

Answer 28

Radium pack

Question 29

Replaced radium as the active source in telecurie therapy units with the rapid growth of nuclear reactor technology

Answer 29

Cobalt 60

Question 30

Advantages of Cobalt 60

Answer 30

Higher specific activity Greater radiation output per curie Higher average photob energy

Question 31

Has a relatively long half-lifeb(30 years) which promised to be a desirable source for telecurie therapy

Answer 31

Cesium 137

Question 32

Cesium 137 disadvantage

Answer 32

Linited specific activity limits its application to head and neck

Question 33

Primarily used in hed and neck therapy

Answer 33

Cesium 137

Question 34

Megavoltage X-ray Generators

Answer 34

Van de Graaf Betatron Linear Accelerator Microtron

Question 35

Heavy-Charged Particle Accelerator

Answer 35

Cyclotron Synchrocyclotron Neutron Beam Generator

Question 36

It is an electrostatic accelerator designes to accelerated electorns to produce high energy x-rays, typically at MV, but can generated beam with energy as high as 10 MV.

Answer 36

Van de Graaf Generator

Question 37

Its uses can be found in sterikizing foods and process materials, accelerating protons for nuclear physics experiments, drving x-ray tubes etc

Answer 37

Van den Graaf Generator

Question 38

A machine capable of accelerating electrons to 2.3 MeV

Answer 38

Betatron

Question 39

Can probide x-ray and electron therapy beams from less than 6 yo more than 40 MeV

Answer 39

Betatron

Question 40

A device which used high frequency electromagnetic waves to accelerate charged particles

Answer 40

Linear Accelerator (LINAC)

Question 41

Can be used to treat superficial tumors or it can be made to strike a target to produce x-rays to treat deep seated tumors

Answer 41

Linear Accelerator (LINAC)

Question 42

The first linear accelerator was installed in ___

Answer 42

Hammersmith Hospital in London

Question 43

Had an 8 MeV x-ray beam and limited gantry rotation

Answer 43

LINAC (in Hammersmith Hospital)

Question 44

An electron accelerator which combines the principles of both the linear accelerator and the cyclotron

Answer 44

Microtron

Question 45

Cape of producing both x-rays and electron beams

Answer 45

Microtron

Question 46

Superficial therapy's potential

Answer 46

50 to 150 kV

Question 47

Source of high energy proton for proton beam therapy

Answer 47

Cyclotron

Question 48

Other uses of cyclotron:

Answer 48

- Generation of neutron beam | - Production of a certain radionuclide

Question 49

Used to generate higher energy charged particles such as Deuterons, Protons, Alpha Particle

Answer 49

Synchrocyclotron

Question 50

Designed to accelerate electrons and protons by means of radiofrequency-modulated magnetic fueld to compensate for the relativistic increase in particle mass

Answer 50

Neutron beam generator

Question 51

2 kinds of neutron beam generator

Answer 51

Electron synchrotron | Proton synchrotron

Question 52

Electron energies of 10 to 100 MeV results to energy in Giga or billion of electron volts

Answer 52

Electron synchrotron

Question 53

The largest proton synchrotron in Fermi National Accelerator Laboratory can generated as 400 GeV energy

Answer 53

Proton synchrotron

Question 54

The world's largest and most powerful particle accelerator.

Answer 54

Large Hadron Collider at CERN

Question 55

It consists of a 27-kilometer ring of superconducting magnets with a number of accelerating structures to boost the energy of the particles along the way

Answer 55

LHC