IMRT/IGRT

Question 1

how many MLC leaves are there

Answer 1

52-120 leaves

Question 2

? dimensional data set req’d for planning

Answer 2

3D

Question 3

in IMRT tx, fluence is

Answer 3

NONUNIFORM

Question 4

in IMRT, MU in ? b/c fld blocked @ any time

Answer 4

more

Question 5

mlc single focus is ? direction & ? ends

Answer 5

one & round

Question 6

mlc double focus is ? edge

Answer 6

flat

Question 7

vmat uses less/more mu compared to imrt

Answer 7

less

Question 8

in inverse tx planning, the weights & intensities of beamlets are

Answer 8

adjusted

Question 9

mlc INTRA leaf transmission is at what area

Answer 9

middle of leaf

Question 10

mlc INTER leaf transmission is at what area

Answer 10

b/n 2 leaves

Question 11

in forward tx planning a ? beam enters pt

Answer 11

UNIFORM

Question 12

compensators are classes of ? system

Answer 12

imrt

Question 13

mlc speed is > ? per second

Answer 13

2

Question 14

dwell time is when leaves are ? in their configuration & beam is >

Answer 14

open; on

Question 15

peacock system is the

Answer 15

collimator

Question 16

crane is ? system

Answer 16

indexing

Question 17

bat stands for

Answer 17

B-mode acquisition & targeting

Question 18

MLC width is

Answer 18

0.5-2.0cm

Question 19

in inverse tx planning, each beam ? as it enters pt

Answer 19

modified

Question 20

in inverse tx planning, beam is ?

Answer 20

nonuniform

Question 21

in inverse tx planning, coverage of tumor can be ?

Answer 21

predetermined

Question 22

mlc INTRA leaf transmission is ?%

Answer 22

0.8-1.5%

Question 23

mlc INTER leaf transmission is ?%

Answer 23

1.1-2.5%

Question 24

wedges are classes of ? systems

Answer 24

imrt

Question 25

examples of transmission blocks are

Answer 25

• dynamic jaws
• moving bars
• mlc
• tomo collimators
• scanned elementary beams

Question 26

transmission blocks are the only 5 that allow

Answer 26

dynamic intensity modulation

Question 27

do leaves have same velocity in dynamic step & shoot?

Answer 27

diff velocity

Question 28

? delivers 1 fld at each gan angle; typically tx 3-5 arcs

Answer 28

IMAT

Question 29

crane system has what accuracy

Answer 29

0.1-0.2mm

Question 30

crane system reduces inhomogeneity to +/- ? %

Answer 30

3%

Question 31

mimic is ? leaves per bank

Answer 31

20

Question 32

? treats 1 or 2 slices tx @ a time

Answer 32

mimic

Question 33

MLC is made of ? cm thick tungsten

Answer 33

8

Question 34

in helical tomo, mlc is while table moves

Answer 34

reconfigured

Question 35

with imrt, it is possible to achieve dose distrib comparable to ?

Answer 35

x-ray/gamma knife

Question 36

imrt can compete with ? therapy

Answer 36

p+

Question 37

imrt is/isn’t effective tx superficial disease

Answer 37

is