Ch 7: Tteatment Delivery Equipment

Question 1

What is the half life of cobalt-60

Answer 1

5.26 years

Question 2

What is the source to axis distance for a Co-60 treatment unit?

Answer 2

80cm

Question 3

Co-60 images have _______(more/less/same) penumbra than images taken on a Linac.

Answer 3

More

Question 4

Photon treatment with a Linac exhibit ______(more/less/same) skin sparring than more traditional units

Answer 4

More

Question 5

Most treatment couches allow for ___ degrees of freedom

Answer 5

4

Question 6

This/these device provide the microwave power to Linac

Answer 6

Klystron and magnetron

Question 7

This structure directs the microwave power toward the accelerator structure

Answer 7

Circulator

Question 8

The length of this structure depends on the energy capability of the machine

Answer 8

Accelerator structure

Question 9

______ is used in photon mode/tx while _____ is used in electron mode/tx

Answer 9

Flattening filter; scattering foil

Question 10

This device monitors the flatness and symmetry of the beam

Answer 10

Ion chamber

Question 11

Linacs, Van de Graaf generators, Betatron, Cyclotron and cobalt-60 are examples of…

Answer 11

High energy units (mega voltages)

Question 12

T/F

Linear accelerators give better dose distribution, faster dose rates, and is more manageable radiation protection.

Answer 12

True

Question 13

Treatment time increased as source decay. Which high beam unit is this?

Answer 13

Cobalt-60

Question 14

The fuzzy edge of the radiation beam is known as?

Answer 14

Penumbra

Question 15

T/F

Increased in penumbra is found with a Linac

Answer 15

False. More penumbra with cobalt 60

Question 16

We call our machines linear accelerators because we accelerate electrons near the rate of ___________.

Answer 16

Speed of light in a straight line

Question 17

SAD is also Called the _____technique

Answer 17

Isocentric

Question 18

What is skin sparing

Answer 18

The deeper the radiation penetrate the body, the less reaction you’re going to have at the skin

Question 19

Why are linac more preferable over cobalt 60?

Answer 19

Because it’s more accurate and cosmetically favorable due to the increase in skin sparring

Question 20

The drive stand houses what 4 major components?

Answer 20

Klystron/magnetron
Waveguide
Circulator
Cooling system

Question 21

Major components of the Linac

Answer 21

Drive stand
Gantry
Treatment couch

Question 22

Varian: drive stand is ______ room

Answer 22

Inside

Question 23

Elekta: driver stand is _______ room, behind _______

Answer 23

Outside; walls

Question 24

Semins: drive stand is _______ room

Answer 24

Inside

Question 25

What are CCTV and their purpose?

Answer 25

CCTV: closed circuit TV are cameras placed inside the treatment room to monitor the patient indirectly

Question 26

Lead walls or ______ ______ is used to stop radiation

Answer 26

Thick concrete

Question 27

The couch has 6 degrees of freedom. What are they

Answer 27

``` Lateral Longitudinal Rotation Pitch Roll Vertical ```

Question 28

What are the components of the gantry (3)

Answer 28

Electron gun Accelerator guide Accelerator structure

Question 29

_______ provide the microwave source

Answer 29

Klystron/magnetron

Question 30

_________ prevent black flow of microwaves by punching the microwaves forward

Answer 30

Circulator

Question 31

_________ allows the gantry and components to operate at a constant temp. Linacs uses cold water

Answer 31

Cooling system

Question 32

_____ produces the electron and injects the electron into the accelerator structure

Answer 32

Electron gun

Question 33

_______ transport microwave power to the accelerator structure

Answer 33

Accelerator guid

Question 34

The _________ amplifies momentum of the electron stream, speed the electron to the speed of light and can range from 30cm to 1m

Answer 34

Accelerator structure

Question 35

T/F | The length of the accelerator structure is dependent on the bea energy

Answer 35

True

Question 36

To deactivate the beam, you could

Answer 36

Turn the key Open the door Push "beam interrupt"

Question 37

What's the max field size for modern linac

Answer 37

40 x 40

Question 38

The backup or secondary ion chamber is set to terminate the beam with ______ number of MU than primary chamber

Answer 38

A higher due to beam pulsating

Question 39

Photon treatments with linac exhibit _____ skin sharing than tradition

Answer 39

More

Question 40

The length of this structure depends on the energy capability of the machine

Answer 40

Accelerator structure/guide

Question 41

This structure directs the microwave power toward the accelerator structure

Answer 41

Waveguide

Question 42

What's the depth of Dmax for a 10 MV beam ?

Answer 42

2.5

Question 43

This device monitors the flatness and symmetry of beam

Answer 43

Ion chamber

Question 44

What's the Dmax for a 4MV beam

Answer 44

1.0cm

Question 45

What's the first thing you should do if the beam fails to terminate

Answer 45

Push the beam interrupt (beam off) button

Question 46

Most linear accelerators have horizontally mouthed accelerators guides

Answer 46

True

Question 47

Wedges

Answer 47

Changes the isodose distribution

Question 48

As energy increases, depth of electron equilibrium (Dmax)

Answer 48

Increases

Question 49

Output of a combalt 60 is measured in terms of

Answer 49

Minutes and seconds

Question 50

A no harm incident is one in which...

Answer 50

An event reached the patient but the patient was not injured