Photon and Electron Beam in the Treatment of Cancer...

Cancer Research Journal 2016; 4(6): 90-105

http://www.sciencepublishinggroup.com/j/crj

doi: 10.11648/j.crj.20160406.12

ISSN: 2330-8192 (Print); ISSN: 2330-8214 (Online)

Photon and Electron Beam in the Treatment of Cancer Patient Based on Monitor Unit Compilation

Alamgir Hossain1, *

, Dayal Chandra Roy2, Samiron Kumar Saha

2, Nazrul Islam

3

1Department of Physics, University of Rajshahi, Rajshahi, Bangladesh 2Department of Physics, Pabna University of Science and Technology, Pabna, Bangladesh 3Department of Radiotherapy, Shaheed Ziaur Rahman Medical College & Hospital, Bogra, Bangladesh

Email address:

[email protected] (A. Hossain) *Corresponding author

To cite this article: Alamgir Hossain, Dayal Chandra Roy, Somiron Kumar Saha, Nazrul Islam. Photon and Electron Beam in the Treatment of Cancer Patient

Based on Monitor Unit Compilation. Cancer Research Journal. Vol. 4, No. 6, 2016, pp. 90-105. doi: 10.11648/j.crj.20160406.12

Received: October 11, 2016; Accepted: November 15, 2016; Published: December 2, 2016

Abstract: The aim of this research is to evaluate the precision of the Monitor unit (MU) calculation in radiation therapy to

survive the cancerous patient, is the measurement of actual dose required to delivered. An essential key of quality assurance in

radiation therapy is verifying the accuracy of monitor unit calculations. Difference between the simpler model calculation and

other modifying method calculation assuming a flat water phantom must be required. The accurate measurement of field size is

the most important fact since many dosimetric quantities were dependent on field size. Perhaps most commonly used method

for determining monitor unit were modified which provide a new formalism.

Keywords: Monitor Unit, Photon, Electron, Cancer

1. Introduction

On the basis of clinical response data the international

commission on radiation units(ICRU) and measurement

states that dosimetry system must be capable of delivering

dose to an accuracy of 5% or 7% [1-2]. More recently

Mijnheer et al. [3, 4] and Wambersie et al [3, 5] proposed

that the standard deviation of the uncertainty in the delivered

dose should not be greater than 3.5%. For more it is need to

improve on the treatment technology to get more accuracy.

The delivery of therapeutic radiation is a medical procedure

and as such requires independent confirmation to ensure

correct and accurate delivery [6]. This confirmation is

accomplished by a comprehensive calculation and chart

review procedure performed both before and throughout

patient treatment [6-10]. An evaluation of the incidence of

radiotherapy errors over 10 years at a large regional cancer

center concluded that treatment plan checks, including MU

verification calculations, were very effective in detecting

documentation and treatment planning errors [6, 11].

Intensity modulated radiation therapy (IMRT) requires an

enhanced quality assurance procedure. This applies in

particular to the step of MU calculation verification. Because

of time constraints, treatment planning systems (TPSs)

normally deal only in an approximate manner with the

physical processes of the interaction of ionizing radiation in

the treatment head and dose deposition inside the patient.

Therefore the determination of the absorbed dose needs

experimental verification [12].

To get more accuracy many factor should be corrected

which take an account for radiation treatment. Some of

these are machine set up, patient adjustment exact tumor

volume correction, field size determination, monitor unit

calculation. All type fractions must included in dose

calculation to get more accurate which depend on the

monitor unit calculation. To ensure correct dose at any

specific tumor cell it must need to know that how many

monitor units is required under normalize condition for

electron and photon. A small number of studies have

already been published on the validity of this commercially

available algorithm. The emphasis is generally on the

verification of output factors and dose distributions in water

[13, 14]. The calculation of monitor units has developed

over past several years as treatment planning for the

91 Alamgir Hossain et al.: Photon and Electron Beam in the Treatment of Cancer Patient Based on Monitor Unit Compilation

improvement in accuracy but the clinical effect of impact

parameter were unclear. The actual distribution of radiation

dose accumulated in normal tissues over the complete

course of radiation therapy is, in general, poorly quantified

[15]. Calibrating the dose per monitor unit (DMU) for

individual patients is important to deliver the prescribed

dose in radiation therapy [16]. Historically, MUs were

determined using a manual calculation process, where the

calculations were based on water phantom data gathered at

time of machine commissioning. There are a variety of

radiation oncology TPSs, from widely used commercial

systems to special purpose systems, with limited

application to a specific delivery modality [17]. Currently,

MU settings required to deliver the prescribed dose are

often calculated by a computerized treatment planning

system using methods and quantities different from those

used in manual MU calculations. The verification

calculation is not and should not be used as a check of the

overall accuracy of the primary TPS; that is the function

of commissioning and continual Quality assurance (QA).

It is crucial that both the primary and the verification

planning systems be properly and thoroughly

commissioned so that they are as accurate as possible.

Monitoring the agreement between the TPS and the

verification system during clinical use can aid in

identifying regions where beam models or data may be

improved, but such monitoring is not a substitute for the

commissioning of either system. Both the TPS and the

verification system should be fully tested and

commissioned following accepted guidelines [6, 18, 19,

20] prior to clinical use. In France, between 2004 and

2005, 23 patients received an overexposure of radiation

resulting from the introduction of the enhanced dynamic

wedge into the clinic, a review of the incident pointed to

the recent elimination of an independent check of the MU

calculation as a major contrib-uting factor [6, 21].

2. Materials and Method

The experiment consists of several parts. We were used

VARIAN CLINAC 2100 CD linear accelerator machine at

Shaheed Ziaur Rahman Medical college & Hospital

(SZMCH), Bogra which provide 6MV, 9MV, 12MV,

15MV photon and electron beam. A water phantom were

used which is considered as a measurement body. Output

factor (OPF), Percent depth dose (PDD), Tissue maximum

ratio (TMR) were measured by using water phantom with

electrometer (model Dose-1). The collected beam data

were then used for beam modeling on the Pinnacle TPS

(Treatment planning system). A set of cylindrical

ionization chamber (farmer type FC-65P) were used to

measure the radiation dose. The machine was calibrated to

ensure that it works properly by comparing different

measured data. To calculated monitor unit, we were used a

simple model by correcting an impact factor. We were

measured output factor in which included phantom

scattering factor (Sp) and air scattering factor (Sc). At first

we were calculated regular square field size for different

irregular field size. We were used 10×10 reference field

size. The water phantom were fed to the LINAC machine

and measured the output for source axial distance (SAD)

& source to surface distance (SSD) technique and also

measured the output factor (OPF), Percent depth dose

(PDD), Tissue maximum ratio(TMR), wedge factor and

other attenuation factor for 6MV & 9MV photon and

electron beam. For irregular field size, the output factor

were obtained by interpolating neighbors field. The

monitor unit was calculated for different field case and

comparing with TPS (treatment planning system)

calculation i.e. with manual calculation which was

showed the better accuracy.

2.1. Calculation Formalism: For Photon Beam

Now-a-days the therapeutic machine has been improved so

we need to improve our treatment technique. The equation

for calculation of monitor unit (MU) in SSD technique that

are used as before is

MU=�

��×��×��×��××�×� �×��×(��) (1)

The scattering factor Sc, Sp and ISF(inverse square factor)

are included into dose rate and taken as a output factor(OPF)

so the equation(1) is reduce to

MU =�

��×��×��××�×� �×(��) (2)

The equation for calculation of monitor unit in SAD

technique

MU=�

��×��×��×.×�×� �×(��) (3)

For Electron Beam: The equation for calculation of

monitor unit is

MU=�

��×��×(��) (4)

2.2. Calculation of Monitor Unit

(1). Monitor unit calculation for Photon: (Example):

Case-1: Cervix

Calculate how much monitor units required to delivered

50cGy in the anterior field to the isocentre using 6MV

photon beam in SAD technique. collimator field size

18.4×17cm2, Depth=8.5cm.

Answer:

Field: 1 AP

Technique: SAD

Field size=18.4×17��~16.67cm2

Depth = 8.5 cm

Energy = 6MV

Dose = 50cGy

Output Factor = 1.0388

Output =1.026cGy/MU

TMR = 0.847

Transmission Factor, TF = 0.998

Cancer Research Journal 2016; 4(6): 90-105 92

MU = �

��×��×��×�=

!"

#."�$×#."%&&×".&'(×".))& = 55.50~56

The machine calculation is 53

Case-2: Tongue


50cGy in the lateral face to the isocentre using 6MV photon

beam in SAD technique. collimator field size 7.8×10cm2,

Depth=8.5cm.

Field: 1 LT Face

Technique: SAD

Equivalent Field size=7.8×10��~8.76��, Depth=5cm,

Energy=6MV,

Dose = 100cGy, Output Factor = 0.986, Output =1.026

cGy/MU, TMR=0.814

MU = �

��×��×��=

#""

#."�$×".)&$×".&#' = 121.43~121

Where the output factor [OPF] and tissue maximum ratio

[TMR] are obtained by interpullating the output factor of

field size 8×8, 8×9, 9×8 and 9×9

The dose per monitor unit is =0.84 cGy

Case-3: Tongue


100cGy in the right lateral face to the isocentre using 6MV

photon beam in SAD technique. Collimator field size

7.2×9.4cm2, Depth=6cm.

Answer:

Field: 1 RT Lateral

Equivalent Technique: SAD

Field size=7.2×9.4��~8.154��, Depth=6 cm

Energy=6MV

Dose=100cGy

Output Factor = 0.982

Output=1.045 cGy/MU

TMR=0.920

Wedge=150

Wedge Factor, WF=0.765

MU = �

��×��×��×=

#""

#."'!×".)&�×".)�"×".($! = 138.45~138

Case-4: Breast


200cGy in the right lateral face to the isocentre using 6MV

photon beam in SSD technique. Collimator field size

7.2×9.4cm2, Depth=6cm, SSD=98cm?

Answer:

Technique: SSD=98cm

Field size=16.2×11.8��~13.65��

Depth=2 cm

Energy=6MV

Dose=200cGy

Output Factor=1.024

Output=0.9964 cGy/MU

PDD=97.96%=0.9796

MU = �

��×��×��=

�""

".))$'×#."�'×".)()$=200

Case-5: Cervix


50cGy in the left-lateral face to the isocentre using 15MV

photon beam in SAD technique. collimator field size

17.5×11.5cm2, Depth =15cm.

Answer:

Field: 1 LT Face

Technique: SAD

Equivalent Field size=17.5×11.5��~13.75��~14cm2,

Depth=15cm, Energy=15MV, Dose=50cGy, Output Factor

=1.025, Output =1.125 cGy/MU, TMR=0.776

MU = �

��×��×��=

!"

#.#�!×#."�!×".(($ = 55.87~56

(2). Monitor unit calculation for electron:

Eample-1: Calculate the MUs required to deliver 200cGy

To a depth of dm 100cm SSD for a 6×6 cm2insert in a

10×10cm2 applicator using 6MeV energy beam?

Answer: For the standard 100 –cm SSD, the monitor unit

can be obtained buy using equation (3). Using data from

table and square root rule for the output factor, the monitor

units are given by.

MU=�

��×��

Where

Field size, FS=6×6 cm2

OP=1.00cGy/MU

OPF=0.963

And D=200 cGy

Then we get

MU=�""

#.""×".)$%=207.68≈207

Eample-2: Calculate the MUs required to deliver

300cGy to a depth of dm 100cm SSD for a 9.4×8.6 cm2

insert in a 10×10cm2applicator using 6MeV energy beam?

Answer: For the standard 100 –cm SSD, the monitor

unit can be obtained buy using equation (3). Using data

from table and square root rule for the output factor, the

equivalent square field size is 9×9 cm2, the monitor units

are given by

MU=�

��×��

Where

OP=1.00cGy/MU

OPF=0.99

And D=200 cGy

Then we get

MU=%""

#.""×".)) =303

3. Discussions

From above result it was shown that every term in

equation (1) & (2) dependent on field size so that it should

be correctly measured of field size. Table-1 showed the

correct measurement of several square field size from


different rectangle size which provides the actual

calculation of monitor unit. Table-2&3 were the

measurement of output factor of different field size for

6&15MV photon beam. Table-4&5 are measurement of

PDD at different depth for different field similarly Table-

6&7 were the measurement of TMR for 6&15 photon

beam.Figure-1 illustrated that the variation of output

factor depending on field size and it was showed that

output factor increased exponentially with increasing field

size. Figure-2&3 illustrated variation of PDD depending

on depth and showed that maximum surface dose occurred

for high energy photon beam.

Figure 1. Output factor Vs Field size.

Figure 2. Measured PDD Vs depth for 6MV photon beam.

Field size

0 10 20 30 40 50

Outp

ut fa

cto

r

0.85

0.90

0.95

1.00

1.05

1.10

1.15

6MV

15MV

Depth in mm

0 50 100 150 200 250 300 350

Perc

ent

dose

0

20

40

60

80

100

120

For 4×4 field size

For 6×6 field size

For 8×8 field size


Figure 3. Measured PDD Vs depth for 10 MV photon beam.

Table 1. Field size determination[Equivalent square field size from rectangle field.

1 2 3 4 5 6 7 8 9 10 11 12

2 2.0

3 2.4 3.0

4 2.7 3.4 4.0

5 2.9 3.7 4.4 5.0

6 3.1 4.0 4.8 5.4 6.0

7 3.3 4.2 5.1 5.8 6.5 7.0

8 3.4 4.4 5.4 6.2 6.9 7.5 8.0

9 3.5 4.6 5.6 6.4 7.2 7.8 8.5 9.0

10 3.6 4.7 5.8 6.7 7.5 8.2 8.9 9.5 10.0

11 3.7 4.8 6.0 6.9 7.8 8.5 9.2 9.8 10.5 11.0

12 3.7 4.9 6.1 7.1 8.0 8.8 9.5 10.2 10.9 11.5 12.0

13 3.8 5.0 6.2 7.2 8.2 9.0 9.8 10.5 11.3 11.9 12.5

14 3.8 5.1 6.3 7.4 8.4 9.3 10.1 10.9 11.6 12.3 12.9

15 3.9 5.1 6.4 7.5 8.5 9.4 10.3 11.1 11.9 12.6 13.3

16 3.9 5.2 6.5 7.6 8.6 9.6 10.5 11.4 12.2 13.0 13.7

17 4.0 5.3 6.6 7.7 8.8 9.7 10.7 11.6 12.5 13.2 14.0

18 4.0 5.3 6.6 7.8 8.9 9.9 10.8 11.8 12.7 13.5 14.3

19 4.0 5.3 6.7 7.8 9.0 10.0 11.0 11.9 12.9 13.7 14.5

20 4.0 5.4 6.7 7.9 9.0 10.1 11.1 12.1 13.0 13.9 14.7

21 4.0 5.4 6.8 7.9 9.1 10.1 11.2 12.2 13.2 14.0 14.9

22 4.0 5.4 6.8 8.0 9.1 10.2 11.3 12.3 13.3 14.2 15.1

23 4.1 5.4 6.8 8.0 9.2 10.3 11.4 12.4 13.4 14.3 15.3

24 4.1 5.5 6.8 8.0 9.2 10.4 11.5 12.5 13.5 14.4 15.4

25 4.1 5.5 6.9 8.1 9.3 10.4 11.6 12.6 13.6 14.6 15.6

26 4.1 5.5 6.9 8.1 9.3 10.5 11.6 12.7 13.7 14.7 15.7

27 4.1 5.5 6.9 8.1 9.4 10.5 11.7 12.7 13.8 14.8 15.8

28 4.1 5.5 6.9 8.2 9.4 10.6 11.7 12.8 13.8 14.9 15.9

30 4.1 5.5 6.9 8.2 9.4 10.6 11.7 12.8 13.9 15.0 16.0

Depth in cm

0 5 10 15 20 25 30 35

Perc

ent d

ose

20

40

60

80

100

120

For 4×4 field size

For 5×5 field size

For 6×6 field size


Table 1. Continued. 1 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 30

2

3

4

5

6

7

8

9

10

11

12

13 13.0

14 13.5 14.0

15 13.9 14.5 15.0

16 14.3 14.9 15.5 16.0

17 14.7 15.3 15.9 16.5 17.0

18 15.0 15.7 16.3 16.9 17.5 18.0

19 15.3 16.0 16.7 17.3 17.9 18.5 19.0

20 15.5 16.3 17.0 17.7 18.3 18.9 19.5 20.0

21 15.7 16.6 17.3 18.0 18.7 19.3 19.9 20.5 21.0

22 16.0 16.8 17.6 18.3 19.0 19.7 20.3 20.9 21.5 22.0

23 16.1 17.0 17.8 18.6 19.3 20.0 20.7 21.3 21.9 22.5 23.0

24 16.3 17.2 18.0 18.8 19.6 20.3 21.0 21.7 22.3 22.9 23.5 24.0

25 16.5 17.4 18.2 19.0 19.8 20.6 21.3 22.1 22.7 23.3 23.9 24.5 25.0

26 16.6 17.5 18.4 19.2 20.1 20.9 21.7 22.4 23.1 23.9 24.3 24.9 25.5 26.0

27 16.7 17.7 18.5 19.4 20.3 21.1 21.9 22.7 23.4 24.1 24.7 25.3 25.9 26.5 27.0

28 16.9 17.8 18.7 19.6 20.5 21.3 22.1 22.9 23.7 24.4 25.1 25.7 26.4 27.0 27.5 28.0

30 17.0 18.0 19.0 19.9 20.8 21.7 22.5 23.3 24.1 24.9 25.7 26.4 27.1 27.7 28.4 29.0 30.0

Table 2. Output Factor For6MV photon beam For SAD Technique output, OP=1.026cGy/MU &SSD output, OP=0.9964 Gy/MU.

3 4 5 6 7 8 9 10 11 12 13

3 0.909 0.917 0.921 0.926 0.928 0.931 0.932 0.934 0.935 0.936 0.936

4 0.918 0.928 0.933 0.939 0.942 0.945 0.947 0.949 0.950 0.952 0.953

5 0.924 0.935 0.942 0.948 0.952 0.956 0.958 0.961 0.962 0.964 0.965

6 0.930 0.943 0.950 0.957 0.962 0.967 0.969 0.972 0.974 0.976 0.977

7 0.934 0.948 0.956 0.964 0.969 0.974 0.977 0.980 0.982 0.984 0.986

8 0.938 0.952 0.961 0.970 0.976 0.981 0.985 0.988 0.991 0.993 0.995

9 0.941 0.956 0.965 0.975 0.981 0.987 0.990 0.994 0.997 0.999 1.001

10 0.944 0.959 0.969 0.979 0.986 0.992 0.996 1.000 1.003 1.006 1.007

11 0.946 0.962 0.972 0.983 0.989 0.996 1.000 1.004 1.007 1.011 1.013

12 0.948 0.964 0.975 0.986 0.993 1.000 1.004 1.008 1.012 1.016 1.018

13 0.949 0.966 0.977 0.988 0.995 1.002 1.007 1.012 1.015 1.019 1.021

14 0.950 0.968 0.979 0.991 0.998 1.005 1.010 1.015 1.019 1.023 1.025

15 0.951 0.970 0.981 0.993 1.000 1.008 1.013 1.019 1.022 1.026 1.028

16 0.953 0.971 0.983 0.995 1.002 1.010 1.015 1.021 1.024 1.028 1.031

17 0.954 0.972 0.984 0.996 1.004 1.012 1.017 1.023 1.027 1.030 1.033

18 0.955 0.973 0.985 0.998 1.006 1.014 1.019 1.025 1.029 1.033 1.035

19 0.956 0.974 0.987 0.999 1.007 1.015 1.021 1.027 1.031 1.035 1.037

20 0.957 0.974 0.988 1.001 1.009 1.017 1.023 1.029 1.033 1.037 1.040

25 0.960 0.979 0.992 1.005 1.014 1.022 1.029 1.035 1.039 1.044 1.047

30 0.962 0.982 0.996 1.009 1.018 1.027 1.034 1.040 1.045 1.050 1.053

35 0.966 0.985 0.999 1.013 1.022 1.031 1.038 1.045 1.050 1.055 1.058

40 0.967 0.988 1.002 1.016 1.025 1.035 1.042 1.048 1.053 1.058 1.062


Table 2. Continued.

14 15 16 17 18 19 20 25 30 35 40

3 0.937 0.937 0.938 0.938 0.939 0.939 0.939 0.941 0.941 0.941 0.942

4 0.953 0.954 0.955 0.955 0.955 0.956 0.956 0.957 0.959 0.959 0.960

5 0.966 0.967 0.967 0.968 0.969 0.969 0.970 0.971 0.972 0.973 0.974

6 0.978 0.980 0.980 0.981 0.982 0.982 0.983 0.985 0.986 0.987 0.987

7 0.987 0.989 0.989 0.990 0.991 0.992 0.993 0.995 0.996 0.997 0.998

8 0.996 0.998 0.999 0.999 1.000 1.001 1.002 1.005 1.006 1.008 1.008

9 1.003 1.004 1.005 1.006 1.007 1.008 1.010 1.012 1.014 1.015 1.016

10 1.009 1.011 1.012 1.013 1.015 1.016 1.017 1.019 1.022 1.023 1.024

11 1.014 1.016 1.018 1.019 1.020 1.021 1.022 1.025 1.028 1.029 1.030

12 1.020 1.022 1.023 1.024 1.025 1.027 1.028 1.032 1.034 1.036 1.037

13 1.023 1.026 1.027 1.028 1.029 1.031 1.032 1.036 1.039 1.040 1.042

14 1.027 1.029 1.031 1.032 1.033 1.035 1.036 1.040 1.043 1.045 1.046

15 1.031 1.033 1.035 1.036 1.037 1.039 1.040 1.045 1.048 1.050 1.050

16 1.033 1.036 1.037 1.038 1.040 1.041 1.042 1.048 1.051 1.053 1.054

17 1.035 1.038 1.039 1.041 1.042 1.043 1.045 1.051 1.054 1.056 1.057

18 1.038 1.040 1.042 1.043 1.045 1.046 1.047 1.053 1.057 1.060 1.061

19 1.040 1.043 1.044 1.046 1.047 1.048 1.050 1.056 1.060 1.063 1.064

20 1.042 1.045 1.047 1.048 1.049 1.051 1.052 1.059 1.063 1.066 1.068

25 1.050 1.053 1.055 1.057 1.058 1.060 1.062 1.069 1.074 1.077 1.079

30 1.056 1.059 1.061 1.063 1.065 1.068 1.070 1.077 1.083 1.086 1.087

35 1.061 1.065 1.067 1.069 1.072 1.074 1.076 1.084 1.090 1.093 1.095

40 1.066 1.069 1.072 1.074 1.076 1.079 1.081 1.089 1.095 1.099 1.101

Table 3. Output Factor For15MV photon beam For SAD Technique output, OP=1.125cGy/MU & SSD OP=0.988 Gy/MU.

3 4 5 6 7 8 9 10 11 12 13

3 0.897 0.911 0.949 0.988 0.956 0.925 0.927 0.928 0.929 0.930 0.931

4 0.912 0.927 0.933 0.939 0.942 0.945 0.947 0.949 0.950 0.952 0.952

5 0.918 0.935 0.942 0.949 0.953 0.957 0.959 0.961 0.962 0.964 0.965

6 0.925 0.943 0.951 0.959 0.963 0.968 0.970 0.973 0.974 0.976 0.977

7 0.929 0.948 0.956 0.965 0.970 0.975 0.978 0.981 0.982 0.984 0.986

8 0.933 0.953 0.962 0.971 0.977 0.982 0.985 0.989 0.991 0.993 0.994

9 0.935 0.956 0.966 0.976 0.982 0.987 0.991 0.994 0.997 0.999 1.000

10 0.938 0.959 0.970 0.980 0.986 0.993 0.996 1.000 1.002 1.005 1.007

11 0.940 0.962 0.973 0.983 0.990 0.996 1.000 1.004 1.007 1.009 1.011

12 0.942 0.964 0.975 0.987 0.993 1.000 1.004 1.009 1.011 1.014 1.016

13 0.943 0.966 0.9+77 0.989 0.996 1.003 1.007 1.011 1.014 1.017 1.020

14 0.945 0.967 0.979 0.991 0.998 1.005 1.009 1.014 1.017 1.021 1.023

15 0.946 0.969 0.981 0.993 1.000 1.007 1.012 1.016 1.020 1.024 1.026

16 0.947 0.970 0.982 0.995 1.002 1.009 1.014 1.019 1.022 1.026 1.029

17 0.948 0.972 0.984 0.996 1.004 1.011 1.016 1.021 1.025 1.028 1.031

18 0.949 0.973 0.985 0.998 1.005 1.013 1.018 1.023 1.027 1.031 1.033

19 0.951 0.974 0.987 0999. 1.007 1.015 1.020 1.025 1.029 1.033 1.035

20 0.952 0.976 0.988 1.001 1.009 1.017 1.022 1.028 1.031 1.035 1.038

25 0.955 0.980 0.993 1.006 1.014 1.022 1.028 1.034 1.038 1.042 1.045

30 0.959 0.983 0.997 1.010 1.019 1.028 1.033 1.039 1.044 1.048 1.051

35 0.962 0.987 1.001 1.015 1.023 1.032 1.038 1.044 1.049 1.053 1.056

40 0.965 0.990 1.004 1.018 1.027 1.036 1.042 1.048 1.053 1.058 1.061


Table 3. Continued. 14 15 16 17 18 19 20 25 30 35 40

3 0.932 0.932 0.932 0.933 0.933 0.933 0.933 0.935 0.9937 0.937 0.938

4 0.953 0.9544 0.954 0.955 0.955 0.956 0.956 0.958 0.960 0.961 0.963

5 0.966 0.967 0.967 0.968 0.968 0.969 0.969 0.972 0.974 0.975 0.976

6 0.978 0.979 0.980 0.981 0.981 0.982 0.982 0.985 0.988 0.988 0.989

7 0.987 0.988 0.989 0.990 0990. 0.991 0.992 0.995 0.997 0.998 0.999

8 0.996 0.997 0.998 0.999 1.000 1.000 1.001 1.005 1.007 1.009 1.008

9 1.002 1.004 1.005 1.006 1.007 1.007 1.008 1.012 1.014 1.016 1.016

10 1.009 1.011 1.012 1.013 1.014 1.014 1.015 1.018 1.021 1.023 1.023

11 1.013 1.016 1.017 1.018 1.019 1.020 1.021 1.024 1.027 1.029 1.029

12 1.018 1.021 1.022 1.023 1.024 1.025 1.026 1.030 1.033 1.035 1.035

13 1.022 1.024 1.025 1.026 1.027 1.029 1.030 1.034 1.037 1.039 1.039

14 1.025 1.027 1.029 1.030 1.031 1.032 1.034 1.038 1.041 1.043 1.044

15 1.029 1.031 1.032 1.034 1.035 1.036 1.038 1.042 1.045 1.047 1.048

16 1.031 1.033 1.035 1.036 1.037 1.039 1.040 1.045 1.048 1.050 1.051

17 1.033 1.036 1.037 1.039 1.040 1.042 1.043 1.048 1.051 1.053 1.054

18 1.036 1.038 1.040 1.041 1.043 1.044 1.046 1.050 1.054 1.056 1.057

19 1.038 1.041 1.042 1.044 1.045 1.047 1.048 1.053 1.057 1.059 1.061

20 1.040 1.043 1.045 1.046 1.048 1.049 1.051 1.056 1.060 1.062 1.064

25 1.048 1.051 1.052 1.054 1.056 1.058 1.059 1.069 1.070 1.073 1.074

30 1.054 1.057 1.059 1.061 1.063 1.065 1.066 1.073 1.078 1.081 1.082

35 1.060 1.063 1.065 1.067 1.069 1.071 1.073 1.080 1.085 1.088 1.090

40 1.064 1.068 1.070 1.072 1.074 1.076 1.078 1.085 1.091 1.094 1.095

Table 4. Normalization percent depth doses(PDD)(d=10cm) for 6-MV x-rays,SSD-100cm.

Dsepth[mm] Field size[mm]

40.0 60.0 80.0 100.0 120.0 150.0 200.0 250.0 300.0 350.0 400.0

115.0 56.671 58.55 60.500 61.950 62.629 63.850 65.200 66.043 66.330 67.085 67.500

120.0 54.750 56.99 59.013 60.025 60.975 62.471 63.750 65.000 64.837 65.720 65.945

125.0 53.075 55.143 57.337 58.525 59.600 60.400 62.025 63.050 63.385 64.195 64.271

130.0 51.467 53.714 55.567 57.037 57.875 59.000 60.500 61.725 61.935 62.400 63.138

135.0 50.125 52.317 53.987 55.233 56.413 57.688 58.850 60.112 60.585 61.275 61.510

140.0 48.600 50.44 52.200 53.775 55.100 56.000 57.500 58.933 58.935 60.016 60.425

145.0 47.067 48.886 51.050 52.287 53.700 54.667 56.425 57.500 57.671 58.620 58.875

150.0 45.550 47.725 49.700 50.950 51.929 53.250 54.813 56.100 56.520 57.225 57.625

155.0 44.200 46.600 48.056 49.586 50.775 52.000 53.333 54.925 55.065 55.920 56.265

160.0 42.950 45.125 47.025 48.300 49.300 50.500 52.100 53.650 53.630 54.725 54.930

165.0 41.771 43.850 45.675 46.800 48.087 49.100 50.725 52.300 52.610 53.530 53.830

170.0 40.425 42.056 44.383 45.600 46.443 47.871 49.833 50.750 51.357 52.225 52.630

175.0 39.213 40.943 43.100 44.500 45.457 46.900 48.600 49.813 50.032 51.020 51.430

180.0 38.086 40.138 41.800 42.800 44.300 45.612 47.400 48.914 49.115 49.925 50.135

185.0 36.900 39.000 40.500 41.800 43.000 44.400 45.914 47.400 47.920 48.675 49.030

190.0 35.500 37.600 39.500 40.611 41.786 43.200 44.900 46.037 46.615 47.520 48.020

195.0 34.550 36.457 38.100 39.725 40.662 42.214 43.556 45.114 45.410 46.400 46.830

200.0 33.650 35.433 37.300 38.871 39.700 41.150 42.600 44.075 44.610 45.300 45.600

205.0 32.700 34.131 36.250 37.388 38.713 39.800 41.537 43.100 43.475 44.168 44.665

210.0 31.713 33.583 35.125 36.275 37.350 38.800 40.643 42.000 42.419 43.214 43.619

215.0 30.850 32.500 34.100 35.571 36.550 37.678 39.500 40.888 41.352 42.252 42.650

220.0 29.967 31.567 33.167 34.650 35.325 37.050 38.575 40.100 40.410 41.315 41.724

225.0 29.100 30.600 32.000 33.500 34.643 36.100 37.667 38.971 39.411 40.263 40.720


Dsepth[mm] Field size[mm]

40.0 60.0 80.0 100.0 120.0 150.0 200.0 250.0 300.0 350.0 400.0

230.0 28.163 29.800 31.367 32.638 33.625 34.867 36.600 37.900 38.230 39.300 39.700

235.0 27.171 28.900 30.625 31.667 32.500 33.900 35.633 37.000 37.375 38.420 38.820

240.0 26.400 28.100 29.700 30.878 31.933 33.300 34.650 36.086 36.615 37.415 38.014

245.0 25.550 27.100 28.717 29.825 30.950 32.217 34.086 35.500 35.757 36.675 37.065

250.0 24.914 26.520 28.100 29.180 30.157 31.450 33.200 34.400 34.800 35.600 36.200

255.0 24.250 25.633 27.300 28.287 29.329 30.686 32.200 33.443 33.920 34.850 35.253

260.0 23.675 25.100 26.614 27.750 28.600 29.713 31.267 32.750 33.100 34.000 34.415

265.0 22.843 24.300 25.800 26.700 27.800 29.000 30.300 31.971 32.405 33.150 33.665

270.0 22.250 23.600 25.025 26.188 27.113 28.388 29.744 31.300 31.614 32.410 32.915

275.0 21.688 23.000 24.300 25.400 26.286 27.500 29.100 30.500 30.900 31.750 32.110

280.0 21.100 22.337 23.667 24.844 25.800 26.833 28.300 29.700 30.310 30.815 31.315

285.0 20.525 21.800 23.037 24.071 25.125 26.263 27.843 29.000 29.305 30.150 30.500

290.0 19.900 21.000 22.500 23.400 24.300 25.600 27.100 28.400 28.500 29.400 29.815

295.0 19.157 20.600 21.900 22.712 23.788 24.825 26.300 27.588 28.000 28.850 29.100

300.0 18.517 20.000 21.217 22.200 0.000 24.117 0.000 26.800 27.214 28.015 28.500

Table 5. Normalization percent depth doses(PDD)(d=10cm) for 15-MV x-rays,SSD-100cm.Values: Dose [%].

Depth[cm] Field size[cm]

4 5 6 7 8 9 10 11

0.0 24.6 25.9 27.1 28.7 30.3 31.6 32.8 34.0

1 78.4 77.1 77.7 78.7 79.7 80.7 81.0 82.3

2 96.5 96.7 96.9 96.9 96.9 97.2 97.5 97.9

3 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0

4 98.7 98.5 98.2 98.5 98.6 98.3 97.7 97.6

5 96.0 95.0 95.0 95.0 94.9 94.7 94.6 94.5

6 90.5 90.8 91.1 91.2 91.2 91.2 91.1 91.0

7 86.7 87.1 87.4 87.3 87.1 87.2 87.3 77.6

8 83.0 83.2 83.3 83.6 83.9 83.6 83.7 83.8

9 79.3 79.7 80.0 80.2 80.4 80.3 80.1 80.3

10 75.3 75.5 76.0 76.4 78.8 76.8 76.8 76.9

11 71.7 71.0 70.2 71.9 73.5 73.7 73.8 74.1

12 68.6 69.1 69.6 70.0 70.3 70.5 70.7 70.9

13 65.2 65.9 66.6 66.9 67.2 67.4 67.6 68.0

14 62.3 62.9 63.5 63.9 64.3 64.5 64.6 65.0

15 58.9 59.8 60.7 61.1 61.4 61.8 62.1 62.2

16 56.9 57.4 57.9 58.5 59.1 59.3 59.5 59.8

17 54.0 54.8 55.6 56.0 56.3 56.6 56.8 57.2

18 51.7 52.3 52.9 53.4 53.9 54.1 54.2 54.7

19 49.2 50.0 50.7 51.2 51.6 51.8 52.0 52.5

20 45.9 47.6 48.2 48.7 49.2 49.5 49.8 50.3

21 45.0 45.6 46.1 46.5 46.9 47.4 47.9 48.2

22 42.8 43.4 44.0 44.6 45.1 45.4 45.6 46.1

23 40.0 41.5 42.0 42.6 43.1 43.5 43.8 44.2

24 39.1 39.6 40.1 40.7 41.2 41.6 42.0 42.2

25 37.4 37.9 38.4 39.0 39.6 39.9 40.1 40.5

26 35.7 38.2 36.6 37.3 38.0 38.3 38.5 38.8

27 33.9 34.5 35.1 38.7 36.2 36.5 36.8 37.2

28 32.6 33.2 33.7 34.2 34.6 35.1 35.6 35.9

29 31.1 31.0 32.1 32.6 33.1 33.5 33.9 34.3

30 29.7 30.2 30.7 31.2 31.6 32.0 32.4 32.6


Table 5. Continued.


12 13 14 15 16 17 18 20 25

35.1 36.2 37.4 38.5 39.6 40.7 41.8 44.0 48.8

0.0 83.0 83.6 84.1 84.6 85.2 85.8 86.5 87.7 90.1

1 98.7 98.6 98.7 99.0 99.1 99.2 99.3 99.5 99.9

2 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0

3 97.4 97.6 97.5 97.6 97.4 97.2 97.0 96.5 96.3

4 94.4 94.4 94.3 94.3 94.1 93.9 93.6 93.2 93.3

5 90.9 90.7 90.6 90.4 90.3 90.2 90.1 89.9 90.4

6 87.6 74.1 80.7 87.2 87.1 87.0 87.0 86.8 86.9

7 83.8 83.0 83.8 83.8 83.6 83.8 83.7 83.7 83.5

8 80.5 80.5 80.6 80.6 72.6 64.5 58.8 40.4 81.0

9 76.9 77.1 77.4 77.6 77.8 77.6 77.7 77.7 77.7

10 74.3 74.2 74.2 74.1 74.2 74.2 74.3 74.4 74.8

11 71.0 71.1 71.3 71.4 71.4 71.4 71.4 71.4 72.0

12 68.3 68.4 68.4 68.5 68.6 68.6 68.7 68.8 69.4

13 65.3 65.5 65.7 65.9 66.0 66.1 66.2 68.4 66.6

14 62.3 62.6 62.8 63.1 63.2 63.3 63.3 63.5 64.0

15 60.0 60.2 60.3 60.5 60.6 60.7 60.9 61.1 61.5

16 57.5 57.7 57.8 58.0 58.2 58.3 58.5 58.8 59.2

17 55.2 55.4 55.6 55.6 55.9 56.0 56.2 56.4 56.9

18 52.9 53.0 53.2 53.3 53.4 53.6 53.7 54.0 55.0

19 50.7 50.8 51.0 51.1 51.3 51.5 51.6 52.0 52.9

20 48.5 48.7 49.0 49.2 49.3 49.5 49.6 49.9 50.7

21 46.5 46.7 47.0 47.2 47.3 47.5 47.6 47.9 48.6

22 44.6 44.9 45.1 45.4 45.5 45.6 45.8 46.0 45.7

23 42.4 42.7 43.1 43.4 42.8 42.1 41.5 40.2 45.0

24 40.8 41.1 41.3 41.6 41.8 42.0 42.3 42.7 43.3

25 49.3 39.4 39.7 40.0 41.0 42.0 42.9 44.9 41.8

26 37.5 37.8 38.0 38.2 38.4 38.5 38.7 39.0 39.9

27 36.1 36.3 36.5 38.7 38.9 37.1 37.3 37.7 38.4

28 34.6 34.0 35.1 35.3 36.5 35.7 35.8 36.2 36.0

29 33.2 33.4 33.7 33.0 34.1 34.3 34.4 34.8 35.0

30

Table 6. Measured Tissue Maximum Ratio[TMR](6 MV)Values: Ratio [%].

Depth[mm] Field size[cm]

1 2 3 4 5 6 7 8

0.0 0.382 0.393 0.404 0.414 0.425 0.436 0.442 0.448

10.0 0.911 0.917 0.923 0.929 0.935 0.940 0.942 0.944

20.0 0.999 0.999 0.998 0.998 0.998 0.998 0.998 0.998

30.0 0.963 0.966 0.968 0.970 0.973 0.975 0.976 0.976

40.0 0.920 0.925 0.929 0.934 0.938 0.942 0.946 0.950

50.0 0.877 0.883 0.889 0.895 0.901 0.908 0.913 0.918

60.0 0.825 0.835 0.846 0.856 0.866 0.877 0.884 0.888

70.0 0.794 0.804 0.815 0.825 0.836 0.846 0.853 0.857

80.0 0.753 0.764 0.775 0.7895 0.796 0.807 0.818 0.828

90.0 0.718 0.730 0.741 0.753 0.764 0.776 0.786 0.793

100.0 0.691 0.701 0.712 0.722 0.732 0.743 0.753 0.763

110.0 0.664 0.674 0.683 0.693 0.703 0.713 0.723 0.732

120.0 0.619 0.632 0.645 0.957 0.670 0.683 0.695 0.705

130.0 0.588 0.601 0.615 0.628 0.641 0.655 0.667 0.675

140.0 0.571 0.582 0.593 0.604 0.615 0.626 0.637 0.645

150.0 0.535 0.548 0.561 0.574 0.587 0.600 0.613 0.622

160.0 0.511 0.524 0.537 0.550 0.563 0.576 0.589 0.598

170.0 0.498 0.508 0.517 0.527 0.537 0.548 0.558 0.569

180.0 0.466 0.478 0.491 0.503 0.515 0.528 0.541 0.549

190.0 0.437 0.450 0.463 0.475 0.488 0.501 0.514 0.524

200.0 0.426 0.437 0.448 0.459 0.470 0.481 0.492 0.502

210.0 0.404 0.415 0.427 0.438 0.450 0.462 0.473 0.482

220.0 0.392 0.402 0.412 0.421 0.431 0.442 0.452 0.461

230.0 0.371 0.381 0.391 0.402 0.412 0.422 0.433 0.442



1 2 3 4 5 6 7 8

240.0 0.349 0.360 0.371 0.381 0.392 0.403 0.414 0.423

250.0 0.335 0.345 0.355 0.365 0.375 0.386 0.396 0.405

260.0 0.326 0.335 0.344 0.353 0.362 0.371 0.381 0.389

270.0 0.311 0.319 0.328 0.337 0.345 0.354 0.363 0.371

280.0 0.300 0.308 0.316 0.324 0.332 0.340 0.349 0.356

290.0 0.289 0.296 0.304 0.311 0.318 0.325 0.333 0.340

300.0 0.261 0.271 0.280 0.290 0.300 0.309 0.319 0.328

310.0 0.249 0.258 0.267 0.277 0.286 0.295 0.305 0.314

320.0 0.237 0.246 0.255 0.264 0.273 0.282 0.291 0.300

330.0 0.226 0.235 0.243 0.252 0.260 0.279 0.278 0.286

340.0 0.216 0.224 0.232 0.240 0.248 0.257 0.265 0.273

350.0 0.206 0.214 0.221 0.229 0.237 0.245 0.253 0.261

360.0 0.196 0.204 0.211 0.219 0.226 0.234 0.242 0.249

370.0 0.187 0.194 0.201 0.209 0.216 0.223 0.231 0.238

380.0 0.178 0.185 0.192 0.199 0.206 0.213 0.220 0.227

390.0 0.170 0.176 0.183 0.190 0.196 0.203 0.210 0.216

400.0 0.162 0.168 0.174 0.181 0.187 0.194 0.200 0.207

Table 6. Continue.


9 10 11 12 13 14 15 16 17

0.0 0.457 0.467 0.477 0.486 0.495 0.504 0.513 0.519 0.524

10.0 0.946 0.948 0.949 0.950 0.952 0.955 0.958 0.969 0.960

20.0 0.999 0999. 0.999 0.999 0.999 1.000 1.000 0.999 0.998

30.0 0.978 0.980 0.980 0.978 0.978 0.979 0.980 0.980 0.979

40.0 0.953 0.956 0.956 0.955 0.955 0.956 0.958 0.958 0.958

50.0 0.923 0.927 0.929 0.929 0.929 0.932 0.935 0.937 0.936

60.0 0.892 0.896 0.898 0.900 0.901 0.906 0.909 0.913 0.912

70.0 0.861 0.865 0.870 0.873 0.876 0.879 0.882 0.884 0.884

80.0 0.835 0.839 0.843 0.847 0.851 0.854 0.857 0.860 0.861

90.0 0.800 0.808 0.815 0.818 0.821 0.826 0.830 0.833 0.835

100.0 0.771 0.778 0.785 0.789 0.794 0.798 0.803 0.808 0.810

110.0 0.741 0.750 0.759 0.763 0.764 0.771 0.775 0.780 0.783

120.0 0.714 0.720 0.726 0.732 0.737 0.743 0.749 0.755 0.760

130.0 0.684 0.692 0.701 0.707 0.712 0.716 0.721 0.726 0.730

140.0 0.653 0.662 0.671 0.680 0.687 0.693 0.697 0.701 0.705

150.0 0.632 0.639 0.647 0.654 0.659 0.665 0.670 0.676 0.761

160.0 0.607 0.615 0.623 0.630 0.636 0641. 0.646 0.651 0.656

170.0 0.581 0.590 0.597 0.604 0.609 0.614 0.620 0.626 0.631

180.0 0.557 0.564 0.570 0.577 0.586 0.594 0.600 0.606 0.611

190.0 0.534 0.542 0.549 0.556 0.563 0.569 0.576 0.581 0.587

200.0 0.511 0.521 0.530 0.540 0.545 0.550 0.555 0.561 0.567

210.0 0.490 0.497 0.504 0.512 0.518 0.524 0.531 0.537 0.542

220.0 0.469 0.477 0.486 0.496 0.501 0.505 0.510 0.517 0.524

230.0 0.450 0.458 0.466 0.474 0.480 0.486 0.492 0.497 0.502

240.0 0.431 0.440 0.447 0.455 0.462 0.468 0.474 0.480 0.485

250.0 0.414 0.422 0.429 0.436 0.443 0.449 0.454 0.460 0.465

260.0 0.397 0.405 0.413 0.420 0.427 0.432 0.437 0.442 0.446

270.0 0.379 0.387 0.394 0.402 0.409 0.415 0.420 0.426 0.431

280.0 0.363 0.371 0.378 0.386 0.393 0.399 0.405 0.410 0.414

290.0 0.348 0.357 0.364 0.370 0.376 0.381 0.387 0.392 0.398

300.0 0.335 0.342 0.348 0.355 0.361 0.367 0.373 0.378 0.382

310.0 0.320 0.327 0.334 0.340 0.346 0.352 0.358 0.363 0.367

320.0 0.306 0.313 0.320 0.325 0.331 0.337 0.343 0.349 0.352

330.0 0.293 0.300 0.306 0.311 0.317 0.323 0.329 0.335 0.338

340.0 0.280 0.287 0293. 0.298 0.303 0.309 0.315 0321. 0.325

350.0 0.268 0.274 0.281 0.285 0.290 0.296 0.302 0.308 0.312

360.0 0.256 0.262 0.269 0.273 0.278 0.283 0.289 0.295 0.299

370.0 0.244 0.251 0.257 0.261 0.266 0.270 0.276 0.282 0.287

380.0 0.233 0.240 0.246 0.250 0.254 0.258 0.265 0.270 0.275

390.0 0.223 0.229 0.236 0.240 0.243 0.247 0.253 0.259 0.264

400.0 0.213 0.219 0.225 0.229 0.233 0.236 0.242 0.248 0.253


Table 6. Continue.


18 19 20 21 22 23 24 25 26 27

0.0 0.530 0.536 0.541 0.550 0.559 0.568 0.577 0.586 0.598 0.609

10.0 0.960 0.961 0.962 0.963 0.965 0.967 0.970 0.972 0.974 0.976

20.0 0.997 0.996 0.995 0.996 0.996 0.997 0.998 0.999 0.999 0.999

30.0 0.979 0.978 0.978 0.978 0.979 0.979 0.980 0.980 0.980 0.980

40.0 0.957 0.957 0.957 0.958 0.959 0.961 0.962 0.963 0.964 0.963

50.0 0.935 0.934 0.934 0.933 0.935 0.937 0.938 0.939 0.940 0.940

60.0 0.911 0.911 0.911 0.911 0.914 0.916 0.919 0.921 0.923 0.923

70.0 0.885 0.885 0.886 0.888 0.890 0.893 0.896 0.899 0.901 0.902

80.0 0.861 0.861 0.861 0.862 0.865 0.868 0.871 0.874 0.876 0.878

90.0 0.836 0.838 0.840 0.842 0.845 0.848 0.850 0.852 0.854 0.855

100.0 0.811 0.812 0.813 0.815 0.818 0.821 0.824 0.826 0.828 0.830

110.0 0.784 0.786 0.788 0.791 0.793 0.797 0.801 0.804 0.806 0.808

120.0 0.762 0.763 0.766 0.769 0.772 0.776 0.779 0.782 0.784 0.786

130.0 0.732 0.735 0.737 0.741 0.745 0.749 0.752 0.755 0.757 0.759

140.0 0.707 0.709 0.712 0.716 0.719 0.723 0.728 0.731 0.734 0.736

150.0 0.684 0.686 0.689 0.693 0.697 0.701 0.705 0.708 0.711 0.713

160.0 0.659 0.862 0.665 0.669 0.673 0.677 0.681 0.685 0.689 0.691

170.0 0.635 0.639 0.643 0.647 0.652 0.658 0.661 0.664 0.666 0.667

180.0 0.615 0.618 0.622 0.626 0.630 0.635 0.640 0.644 0.647 0.650

190.0 0.592 0.595 0.598 0.602 0.605 0.611 0.615 0.619 0.621 0.623

200.0 0.573 0.575 0.578 0.581 0.585 0.589 0.593 0.597 0.600 0.603

210.0 0.548 0.551 0.555 0.559 0.564 0.569 0.574 0.578 0.581 0.584

220.0 0.530 0.534 0.537 0.541 0.545 0.549 0.553 0.557 0.561 0.264

Table 6. Continue.


28 29 30 31 32 33 34

0.0 0.620 0.632 0.643 0.648 0.654 0.660 0.666

10.0 0.978 0.980 0.982 0.983 0.984 0.985 0.985

20.0 0.999 0.999 0.999 0.999 0.999 0.998 0.998

30.0 0.980 0.980 0.980 0.980 0.980 0.981 0.981

40.0 0.963 0.962 0.961 0.961 0.962 0.963 0.964

50.0 0.940 0.939 0.939 0.940 0.941 0.942 0.944

60.0 0.923 0.923 0.923 0.923 0.924 0.924 0.924

70.0 0.900 0.899 0.899 0.899 0.899 0.900 0.902

80.0 0.877 0.877 0.877 0.877 0.878 0.879 0.880

90.0 0.855 0.855 0.855 0.856 0.856 0.857 0.858

100.0 0.831 0.830 0.831 0.831 0.833 0.834 0.835

110.0 0.810 0.809 0.810 0.810 0.811 0.812 0.814

120.0 0.788 0.788 0.788 0.788 0.789 0.790 0.792

130.0 0.761 0.762 0.762 0.764 0.765 0.764 0.769

140.0 0.738 0.740 0.740 0.740 0.742 0.743 0.744

150.0 0.715 0.716 0.717 0.719 0.721 0.723 0.725

160.0 0.684 0.696 0.696 0.697 0.698 0.699 0.700

170.0 0.668 0.670 0.671 0.673 0.675 0.678 0.680

180.0 0.653 0.655 0.657 0.658 0.659 0.661 0.662

190.0 0.625 0.627 0.628 0.630 0.632 0.635 0.637

200.0 0.606 0.608 0.611 0.613 0.615 0.617 0.619

210.0 0.586 0.589 0.591 0.593 0.595 0.596 0.599

220.0 0.567 0.570 0.573 0.575 0.576 0.578 0.580


Table 7. Measured Tissue maximum Ratio[TMR] for 15mv.Values: Ratio [%].


1 2 3 4 5 6 7 8

0.0 0.193 0.206 0.218 0.231 0.244 0.257 0.271 0.286

1.0 0.708 0.717 0.725 0.733 0.741 0.749 0.758 0.767

2.0 0.935 0.938 0.942 0.945 0.949 0.953 0.952 0.952

3.0 1.007 1.006 1.005 1.004 1.003 1.003 1.003 1.003

4.0 1.008 1.007 1.006 1.005 1.004 1.003 1.004 1.006

5.0 0.983 0.984 0.985 0.986 0.987 0.988 0.988 0.987

6.0 0.941 0.946 0.950 0.955 0.959 0.964 0.966 0.965

7.0 0.919 0.924 0.928 0.932 0.937 0.942 0.942 0.940

8.0 0.901 0.903 0.906 0.909 0.912 0.915 0.918 0.920

9.0 0.869 0.874 0.879 0.883 0.888 0.893 0.897 0.898

10.0 0.840 0.844 0.849 0.853 0.858 0.863 0.867 0.871

11.0 0.801 0.809 0.817 0.825 0.833 0.842 0.848 0.849

12.0 0.784 0.791 0.797 0.803 0.810 0.817 0.823 0.826

13.0 0.754 0.762 0.769 0.777 0.785 0.793 0.800 0.803

14.0 0.735 0.742 0.749 0.755 0.762 0.770 0.776 0.780

15.0 0.694 0.707 0.714 0.724 0.734 0.745 0.754 0.758

16.0 0.692 0.699 0.705 0.712 0.718 0.726 0.733 0.738

17.0 0.661 0.670 0.678 0.687 0.695 0.704 0.713 0.717

18.0 0.650 0.656 0.663 0.669 0.674 0.683 0.690 0.695

19.0 0.624 0.631 0.639 0.646 0.654 0.663 0.671 0.676

20.0 0.602 0.609 0.617 0.624 0.632 0.641 0.649 0.655

21.0 0.591 0.597 0.603 0.610 0.616 0.623 0.630 0.635

22.0 0.569 0.576 0.582 0.589 0.596 0.604 0.611 0.617

23.0 0.555 0.561 0.567 0.573 0.579 0.586 0.593 0.599

24.0 0.539 0.544 0.550 0.555 0.561 0.567 0.573 0.579

25.0 0.520 0.526 0.532 0.538 0.544 0.551 0.558 0.564

26.0 0.507 0.513 0.518 0.523 0.528 0.534 0.540 0.547

27.0 0.482 0.489 0.496 0.502 0.509 0.517 0.524 0.531

28.0 0.472 0.479 0.485 0.491 0.497 0.504 0.511 0.517

29.0 0.459 0.465 0.470 0.476 0.481 0.488 0.494 0.500

30.0 0.440 0.446 0.453 0.459 0.465 0.472 0.479 0.486

31.0 0.427 0.433 0.439 0.445 0.451 0.458 0.465 0.472

32.0 0.414 0.420 0.426 0.432 0.438 0.444 0.451 0.457

33.0 0.401 0.407 0.413 0.419 0.424 0.431 0.437 0.444

34.0 0.389 0.395 0.400 0.406 0.411 0.418 0.424 0.430

35.0 0.377 0.383 0.388 0.393 0.399 0.405 0.411 0.417

36.0 0.366 0.371 0.376 0.381 0.387 0.392 0.398 0.404

37.0 0.355 0.360 0.365 0.370 0.375 0.380 0.386 0.390

38.0 0.344 0.349 0.353 0.358 0.363 0.369 0.374 0.380

39.0 0.333 0.338 0.343 0.347 0.352 0.357 0.363 0.368

40.0 0.323 0.327 0.332 0.336 0.341 0.346 0.352 0.357

Table 7. Continue.


9 10 11 12 13 14 15 16 17

0.0 0.298 0.310 0.322 0.343 0.343 0.353 0.363 0.373 0.384

1.0 0.775 0.784 0.791 0.799 0.805 0.811 0.817 0.822 0.828

2.0 0.953 0.955 0.960 0.964 0.968 0.971 0.974 0.976 0.977

3.0 1.003 1.002 1.002 1.002 1.002 1.002 1.002 1.002 1.001

4.0 1.003 0.998 0.995 0.995 0.995 0.997 0.998 0.998 0.996

5.0 0.985 0.982 0.981 0.982 0.983 0.983 0.984 0.983 0.981

6.0 0.965 0.964 0.964 0.964 0.964 0.963 0.962 0.961 0.960

7.0 0.939 0.940 0.941 0.944 0.947 0.947 0.946 0.945 0.944

8.0 0.921 0.919 0.918 0.920 0.921 0.923 0.924 0.925 0.925

9.0 0.898 0.896 0.895 0.898 0.902 0.903 0.904 0.905 0.905

10.0 0.873 0.874 0.874 0.875 0.877 0.880 0.883 0.886 0.887

11.0 0.851 0.852 0.854 0.857 0.861 0.863 0.864 0.864 0.864

12.0 0.829 0.831 0.833 0.835 0.837 0.840 0.842 0.844 0.846

13.0 0.806 0.808 0.810 0.814 0.818 0.822 0.824 0.826 0.827



9 10 11 12 13 14 15 16 17

14.0 0.783 0.785 0.787 0.791 0.796 0.800 0.803 0.806 0.808

15.0 0.761 0.765 0.769 0.772 0.773 0.776 0.780 0.783 0.787

16.0 0.743 0.747 0.750 0.753 0.757 0.760 0.763 0.766 0.768

17.0 0.721 0.724 0.727 0.730 0.736 0.741 0.744 0.747 0.749

18.0 0.700 0.704 0.706 0.709 0.715 0.721 0.725 0.729 0.732

19.0 0.681 0.685 0.688 0.690 0.696 0.702 0.706 0.708 0.710

20.0 0.660 0.665 0.668 0.672 0.678 0.684 0.668 0.690 0.691

21.0 0.639 0.644 0.650 0.656 0.661 0.666 0.670 0.673 0.676

22.0 0.623 0.628 0.632 0.635 0.640 0.646 0.651 0.655 0.659

23.0 0.604 0.610 0.615 0.619 0.625 0.631 0.636 0.640 0.643

24.0 0.585 0.592 0.597 0.601 0.606 0.610 0.614 0.618 0.623

25.0 0.571 0.577 0.581 0.584 0.589 0.594 0.599 0.603 0.606

26.0 0.554 0.562 0.566 0.570 0.574 0.578 0.583 0.587 0.591

27.0 0.538 0.545 0.549 0.553 0.557 0.563 0.568 0.572 0.575

28.0 0.522 0.528 0.533 0.539 0.545 0.549 0.553 0.557 0.560

29.0 0.505 0.511 0.516 0.522 0.528 0.533 0.538 0.542 0.546

30.0 0.491 0.496 0.501 0.507 0.512 0.518 0.523 0.528 0.531

31.0 0.576 0.481 0.486 0.492 0.497 0.503 0.508 0.513 0.516

32.0 0.462 0.467 0.472 0.478 0.483 0.488 0.494 0.499 0.502

33.0 0.448 0.453 0.458 0.463 0.469 0.474 0.479 0.485 0.488

34.0 0.435 0.439 0.444 0.450 0.455 0.460 0.466 0.471 0.474

35.0 0.422 0.426 0.431 0.436 0.441 0.447 0.452 0.457 0.461

36.0 0.409 0.413 0.418 0.423 0.428 0.433 0.439 0.444 0.447

37.0 0.396 0.401 0.405 0.410 0.415 0.421 0.426 0.431 0.435

38.0 0.384 0.388 0.393 0.398 0.403 0.408 0.413 0.418 0.422

39.0 0.372 0.377 0.381 0.386 0.391 0.396 0.401 0.406 0.410

40.0 0.361 0.365 0.369 0.374 0.379 0.384 0.389 0.394 0.398

Table-8shows the correct measurement of output at the maximum dose depth distance (Dmax) and reference depth (Zref) for

different beam of electron. Table-9 is the measurement of output factor for different field size and electron beam.

Table 8. Measured output of electron beam for several energy.

Output

Energy Dmax Zref

6 1.00 1.00

9 1.015 1.01

12 0.996 0.996

15 1.00 0.989

18 0.98 0.955

22 0.939 0.893

Table 9. Output factor.

Output Factor

Energy Applicator 6×6 10×10 15×15 20×20 25×25

6

10×10

0963 1 1 1.019 1.006

9 0.98 1 0.997 0.986 0.965

12 0.982 1 0.994 0.979 0.952

15 0.967 1 0.989 0.973 0.944

18 20×20 1.035 1.036 1.018 1 0.97

22 1.047 1.035 1.017 1 0.969

Table 10. Depth vs Dose(dose curve).

Table Depth Vs PDD

Energy Ds Dmax 95% 90% 50% Rp Applicator

6 81% 13.0 17.0 18.5 23.6 30.0

10×10 9 84% 21.0 25.5 27.5 35.5 43.6

12 88% 27.0 36.0 38.5 50.3 61.0

15 93% 32.0 43.0 47.0 61.7 75.0

18 95% 24.5 49.0 55.4 74.3 90.0 20×20

22 95% 24.3 50.5 59.0 84.2 103.5


Figure 4. Measured percent depth dose for electron beam.

Figure: 4illustrated that as the energy of the electron beam

increased the maximum dose occurred at higher depth. From

above we observed that many corrections were included to

get more accuracy on the monitor unit calculation. From

case_1(cervix), the required monitor unit was 56 but

according to TPS(treatment planning system) calculation it

was 53 which was lesser than required, suppose we may

assume the machine calculation is greater or less than 3 from

the our calculation which means that per 100cGy the access

or less monitor unit is 6, To delivered 5000cGy, it will be

300cGy so that the patient get more or less 300cGy from

required which take a violent effect and the normal tissue

around the tumor may be get permanently damaged if it is

excess, it may not possible to damage the tumor cell if it is

lesser than accurate. The result will more accurate if the

ionization chamber perfect work due to use old ionization

chamber.

4. Conclusion

Computer calculations are commonly verified using an

independent manual procedure. It is difficult to calculate

treatment delivery monitor units for this variant of IMRT using

manual method, since manual calculations are not feasible, it is

important both to understand and to verify the calculation of

treatment monitor units by the planning system algorithm. A

formal analysis was made of the dose calculation model and

the monitor unit calculation embedded in the algorithm.

Experimental verification of the dose delivered by plans

computed with methodology demonstrated an agreement of

better than 4% between the dose model and measurement. So

it must be required to take corrected form for the calculation of

monitor unit to survive the cancerous patient.

Appendix

Notation and Definition.

D=The absorbed does at the point of interest from the

individual field under calculation.

OP=Output or The dose rate or does per monitor unit at the

point of interest.

d=Depth of the point of calculation.

1��=Water-equivalent depth of the point of calculation.

1" =The normalization depth for photon and electron

dosimetry. For photon, do= 10cm is recommended, but not

required. For each photon beam, do is independent of field

size and shall be greater than or equal to the maximum dm.

For electrons, do is taken to be the depth of maximum dose

along the central axis for the same field incident on a water

phantom at the same SSD. It is field-size de-pendent.

Dm=The depth of maximum dose on the central axis.

OAR (d,x)= Off-axis ratio (sec. 1.A.1.f). The ratio of the

open field dose rate at an off-axis point to that for the same

field (e.g, 10*10 cm2) shifted such that the point of

calculation lies on the central axis. The Primary Off-Axis

Ratio, POAR, is preferred to be used for OAR (d,x).

PDD (d,r,SSD)=Percent depth dose. The ratio, expressed

as a percentage, of the dose rate at depth to the dose rate at

dm in a water phantom for a given field size and SSD.

PDD (d,r,SSD)= Normalized percent depth dose

(sec.1.A.1.b). The ratio, expressed as a percentage, of the

dose rate at depth to the dose rate at the normalization depth

in a water phantom for a given field for a given field size and

SSD.

SAD= Source-axis distance. Distance between the x-ray

physical source position and the isocenter. For most linear

accelerators, this value is nominally 100cm.

SPD= Source-point distance. The distance from the x-ray

physical source to the plane (perpendicular to the central

axis) that contains the point of calculation.

SSD=source-surface distance. The distance along the

central axis from the physical source to the patient/phantom

surface.

SSDo=Standard source-surface distance. The distance

along the central axis from the physical source to the

patient/phantom surface under normalization conditions.

SSDeff=Effective source surface distance. The distance

along the central axis from the effective source to the patient

/phantom surface, determined by beat fit of output versus the

inverse of the distance squared.

TPR (d, rd)=Tissue phantom ratio (sec. 1.A.1.c). the ratio

of the dose rate at a given depth in phantom to the dose rate

at the normalization depth for a given field size.

TF=Try factor. The ratio of the central-axis dose rate for

a given field with and without a blocking tray. TF is

assumed independent of depth and field size in this report.

This factor may be used to account for the attenuation

through additional materials (e.g, special patient support

devices) as needed.

Depth Vs Dose curve

Measured percent dose

100% 95% 90% 85% 50% 30%

Dep

th

0

20

40

60

80

100

120

6MV

9MV

12MV

15MV

18 MV

22MV


WF (d,rd,x)=wedge factor (sec.1.A.1.i). the ratio of the

dose rate at the point of calculation for a wedged field to

that for the same field without a wedge modifier. The

wedge may be a physical filter or not (i.e, dynamic or

virtual). Depending on the type and angle of the WF may

depend on the wedge angle, field size, depth, and off-axis

distance.

Rmax=The maximum range (cm) is define as the depth at

which maximum electron absorbed.

Rp=It is the practical range define as the depth at which

the tangent plotted through the steepest section of the

electron depth dose curve intersects with the extrapolation

line of the background.

References

[1] International Commission on Radiation Units and Measurements, “Determination of absorbed dose in a patient irradiated by beams of X or gamma rays in radiotherapy procedures,” ICRU Report No. 24 (International Commission on Radiation Units and Measurements, Washington, (1976).

[2] Ohn P. Gibbons, John A. Antolak, David S. Followill, M. Saiful Huq, Eric E. Klein, Kwok L. Lam, Jatinder R. Palta, Donald M. Roback, Mark Reid and Faiz M. Khan “Monitor unit calculations for external photon and electron beams: Report of the AAPM Therapy Physics Committee Task Group No. 71’ Med. Phys. 41 031501 (2014).

[3] Konrad W. Leszczynski and Peter B. Dunscombe “Independent corroboration of monitorunit calculations performed by a 3D computerized planning system’’ Int. J. Radiat, Oncol, Biol, Phys 1, S120 (2000).

[4] B. J. Mijnheer, J. J. Battermann, and A. Wambersie, ‘‘What degree of accuracy is required and can be achieved in photon and neutron therapy?’’ Radiother. Oncol. 8, 237–252(1987).

[5] A. Wambersie, J. Van Dam, G. Hanks, B. J. Mijnheer, and J. J. Battermann, ‘‘Whataccuracy is needed in dosimetry?,’’ IAEA–TECDOC 734, 11–35 (1994).

[6] Robin L. Stern, Robert Heaton, Martin W. Fraser, S. Murty Goddu, Thomas H. Kirby, Kwok Leung Lam, Andrea Molineu and Timothy C. Zhu, “Verification of monitor unit calculations for non-IMRT clinical radiotherapy’’ Report of AAPM Task Group 114, Med. Phys. 38, S-504 (2011).

[7] G. J. Kutcher et al, “Comprehensive QA for radiation oncology: Report of AAPMRadiation Therapy Committee Task Group 40,” Med. Phys. 21, 581–618 (1994).

[8] L. Duggan, T. Kron, S. Howlett, A. Skov, and P. O’Brien, “An independent check of treatment plan, prescription and dose calculation as a QA procedure,” Radiother. Oncol. 42, 297–301 (1997).

[9] American College of Radiology, “Practice guideline for 3D external beam radiation planning and conformal therapy” (2006)(http://www-naweb.iaea.org/nahu/dmrp/pdf_files/ToC.pdf).

[10] The Royal College of Radiologists, Society and College of Radiographers, Institute of Physics and Engineering in Medicine and National Patient Safety Agency and British Institute of Radiology, Towards Safer Radiotherapy (The

Royal College of Radiologists, London, 2008).https://www.rcr.ac.uk/towards-safer-radiotherapy.

[11] T. K. Yeung, K. Bortolotto, S. Cosby, M. Hoar, and E. Lederer, “Quality assurance in radiotherapy: Evaluation of errors and incidents recorded over a 10 year period,” Radiother. Oncol.74, 283–291, (2005).

[12] M. N. Anjum, W. Parker, I. Aldahlawi, R. Ruo, M. Afzal, “Evaluation of treatment planning system monitor unit calculations for three intensity modulated radiotherapy delivery techniques” Iran. J. Radiat. Res, 9(3), 145-150 (2011).

[13] Popple RA, Brezovich IA, Pareek PN, Duan J, Shen S, Wu X. Performance of acommercial macro Monte Carlo dose calculation algorithm for determining output factors of clinical electron fields. Technol Cancer Res Treat; 8(4):307-14. 2009.

[14] Hu YA, Song H, Chen Z, Zhou S, Yin F. Evaluation of an electron Monte Carlo dose calculation algorithm for electron beam. J App Clin Med Phys; 9(3):1–15.2008.

[15] D. A. Jaffray, P. E. Lindsay, K. K. Brock, J. O. Deasy, and W. A. Tome, “Accurate accumulation of dose for improved understanding of radiation effects in normal tissue,”Int. J. Radiat, Oncol, Biol, Phys. 76, S135– S139 (2010).

[16] Kenji Hotta, Ryosuke Kohno, Kohsuke Nagafuchi, Hidenori Yamaguchi, Ryohei Tansho, Yoshihisa Takada, and Tetsuo Akimoto, “Evaluation of monitor unit calculation based on measurement and calculation with a simplified Monte Carlo method for passive beam delivery system in proton beam therapy’’. J. Radiat, Oncol, Biol, Phys.16 S228-S229(2015).

[17] Jennifer B. Smilowitz, Chair, Indra J. Das, Vladimir Feygelman, Benedick A. Fraass,Stephen F. Kry, Ingrid R. Marshall, Dimitris N. Mihailidis, Zoubir Ouhib, TimothyRitter, Michael G. Snyder, Lynne Fairobent, AAPM Staff “Commissioning and QA of Treatment Planning Dose Calculations — Megavoltage Photon and Electron Beams ‘’ Int.J. Radiat, Oncol, Biol, Phys 16, S14-S15(2015).

[18] B. Fraass, K. Doppke, M. Hunt, G. Kutcher, G. Starkschall, R. Stern, and J. Van Dyke, “American Association of Physicists in Medicine Radiation Therapy Committee TaskGroup 53: Quality assurance for clinical radiotherapy treatment planning,” Med. Phys.25, 1773–1829 (1998).

[19] P. Andreo, J. Izewska, K. Shortt, and S. Vatnitsky, “Commissioning and Quality assurance of computerized planning systems for radiation treatment of cancer,” IAEA Technical Report Series No. 430 (International Atomic Energy Agency, 2004).

[20] I. A. D. Buinvis, R. B. Keus, W. J. M. Lenglet, G. J. Meijer, B. J. Mijnheer, A. A. van ‘teld, J. L. M. Venselaar, J. Welleweerd, and E. Woudstra, “Quality assurance of 3-Dtreatment planning systems for external photon and electron beams,” Report No. 15 (The Netherlands Commission on Radiation Dosimetry, (2006).

[21] French Nuclear Safety Authority ASN, “Epinal radiotherapy accident,” ASN Report No.2006 ENSTR 019 IGAS 2007-015P, 2007. http://www.french-nuclear-safety.fr/Media/Files/ASN_report_n_2006_ENSTR_019_-_IGAS.

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