The 3rd International Conference on Theoretical and Applied Physics 2013
and Simposium Fisika Nasional XXVI.
October, 10-11, 2013 Malang, East Java, Indonesia
Physical Parameters Measurement to Analyze the X-ray
Radiation for Radio diagnostic Quality Control in Hospitals
Syamsir Dewang*, Bualkar Abdullah1, Bannu Abd. Samad1, Nur Hasanah1
1.
Physics Department, Faculty of Mathematics and Natural Sciences, Hasanuddin University, Makassar.
*Email: dewang163@yahoo.com.
Abstract. Medical physics have given contribution to medical technology. The medical physician has several fields of research;
there are radio diagnostics, radio therapy and nuclear medicine. In the case of radio diagnostic, we developed a research to
measure physical parameter of X-ray radiation such as: tube voltage (kV), exposure time (mS), X-ray exposure (mGy),
exposure rate (mGy/S), and Half Value Layer (HVL) in several Hospitals of Makassar city; Haji, Bhayangkara, and Jala Ammari
Navy hospital, respectively. These measurements were intended to analyze the quality parameters for quality control of X-ray
radiation such as: Voltage accuracy (kV), Reproducibility (CV), Current linearity coefficient (CL), and HVL in mm-Al as well.
The standard value for quality parameters were regulated by Nuclear Energy Regulatory Agency (PERKA BAPETEN) Nu: 9th,
2011, and the International atomic energy agency (IAEA). Standard value as the quality control for radiation out put of X-ray
machine. Parameter value is accepted by IAEA regulation in tolerance limit of reproducibility (Cv) ≤ 0.05, current linearity
coefficient
(CL)
≤
0.1,
and
HVL
is
more
then
2.1
mm-Al
of
70
kV,
respectively.
Analyses show that physical parameter of X ray radiation in Jala Ammari Navy hospital for reproducibility (CV), linearity (CL)
and HVL are exceed the minimum value from regulation, in this case, it is needed for calibration. Mean while, the all parameter
values in Bhayangkara haspital were accepted in good condition. However, Haji hospital is also good condition accept the
measurement of reproducibility for exposure dose out put was 0.3417, and CV for exposure time was 0.3417, these exceed the
standard values and there were recomended for calibration.
Keywords: X-ray radiation, ray exposure, radio diagnostic, hospital.
PACS : 87.59.B-
1. INTRODUCTION
Developing of science and technology
contributed to Medical physics, especially; the X-ray
application for radio diagnostic and radio theraphy
in the field of medicine. The X-ray spectrum ranges
10 to 100 nm wavelength, it has a narrow
bandwidth, high energy and strong power.
Furthermore, it’s can be used to detect the internal
body of patient. The X-ray is an electromagnetics
wave; when it is applied to expose for a long time;
however, the patient, medical physicion and doctor
of radiology can derive the effect of radiation.
Meanwhile, X-ray radiation will produce low quality
or inaccurate source of radiography, or giving over
diagnosis to doctor and to medical operator[1].
The problem is how to use the X-ray machine
in good condition, here, it is needed to regularly
calibrate of X ray machine in each hospitals. The
standard for calibration of X-ray radiography is
regulated by International Atomic Energy Agency
(IAEA) and Nuclear Energy Regulatory Agency of
Indonesia, such as in PERKA BAPETEN Nu: 9th,
2011[2].
This research is inteded to measure physical
parameter of X-ray radiation, i.e. Tube voltage (kV),
exposure time (mS), X-ray exposure (mGy),
exposure rate (mGy/S), and Half Value Layer
(HVL) in mm Al of Xray machine. This observation
measured several Hospitals of Makassar city; such
as in Haji, Bhayangkara, and Jala Ammari Navy
hospitals, respectively. The aim of research is going
to giving the recommedation of each Xray machine
for observing physical parameter, within the
accepted or non required value for IAEA and
PERKA BAPETEN.
2. THEORY AND METHOD
The operational of X-ray machine has two
principle goals of quality assurance. The first is
obtain accurate and timely diagnosis, the second is
minimization of radiation exposure and obtain high
image quality. Performance the X-ray machine can
be control by optimum operation of physical
parameters such as: current linearity, reproducibility,
exposure time, X-ray tube efficiency, accuracy of
kV , mA, time, focal spot size . and half value
layer[3].
The 3rd International Conference on Theoretical and Applied Physics 2013
and Simposium Fisika Nasional XXVI.
October, 10-11, 2013 Malang, East Java, Indonesia
The first formulation of the present paper is to
calculate the current linearity (CL) for checking the
current stability of X-ray machine. The current
linearity is defined by formulation such as equation
as follows: [4]
𝑋𝑚𝑎𝑥 −𝑋𝑚𝑖𝑛
𝑋𝑚𝑎𝑥 +𝑋𝑚𝑖𝑛
(1)
Where: CL is current linearity coefficient, 𝑋𝑚𝑎𝑥 is
maximum of exposure rate/current tube, and 𝑋𝑚𝑖𝑛 is
minimum of exposure rate/current tube in
(mGy/mAS).
The standard value of linearity current CL is
less then 0.1. The value was arranged by
International Atomic Energy Agency (IAEA) and
Nuclear Energy Regulatory Agency of Indonesia in
PERKA BAPETEN Nu: 9th, 2011.
The second view of this consideration is formulation
of reproducibility dose out put of X-ray radiation.
The reproducibility is variation coeficient (CV) of
physical variable, which is derived by standard
deviation per unit rate of high voltage, time, or dose
output for X-ray machines. The analysis is derived
by difference between the measured and nominal
value of physical parameter for CV calculation. The
formulation of CV is written as follows:
𝐶𝑣 =
𝑆
𝑋̅
=
1
√∑𝑛𝑖=1(𝑋𝑖
𝑋̅
FIGURE 1. Standard curve HVL (mm Al) vs
Voltage (kVp).
− 𝑋̅Ẍ)2 /(𝑛 − 1) . . . . . ..(2)
Where CV is the reproducibility or coefficient
variation, S is the estimator of standard deviation,
the series of measurements dose [mGy], time [ms] or
voltage [KV], 𝑋̅ is rate of measured variable. The
reproducibility value is formed over a range of
clinical settings. A standard for reproducibility
within the accepted value of IAEA is CV ≤ 0.05.
The third consideration is Half-value layer
(HVL) which is one of the important parameters for
Quality Assurance (QA) and Quality Control (QC)
of X-ray tube. The HVL filtration of X-ray source
is expressed in units of distance (mm or cm), where
50% of the incident energy has been attenuated. The
HVL is often used in radiography simply because it
is easier to remember values and perform simple
calculations. Increasing the penetrating energy of a
stream of photons will result in an increase in a
material's HVL [5].
The standard value for HVL in (mm-Al) is
required for IAEA that is exceed the minimum
HVL (mm Al)
𝐶𝐿 =
value, passed above 2.3 mm-Al at 70 KV.
Figure 1 shows the standard curve HVL
(mmAl) vs voltage (KV) is accepted by IAEA.
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0
Acceptable
Non cceptable
50
60
70
80
90 100 110 120 130 140 150
kVp
Figure 1 shows the accepted value of HVL (mm Al)
vs kV above the standard curve, and value below
curve is non acceptable.
METHOD
This research measured the radiation of
Xray machine in three hospitals such as in Haji,
Bhayangkara police and Jala Ammari Navy hospital,
respectively. Measuring of radiation output dose
using detector of Barracuda tools. The experimental
setup such as in Figure 1.
Sistem pengaturan alat pesawat sinar X
X-ray Tube
Measurement
of X-ray dose
out put
9/24/2013
Patient Table
Figure 2. Experimental setup of X-ray measurement
The procedure of measurement such as in
The 3rd International Conference on Theoretical and Applied Physics 2013
and Simposium Fisika Nasional XXVI.
October, 10-11, 2013 Malang, East Java, Indonesia
Figure 2 shows the X-ray radiation source
as beam spot from X-ray tube to object in patient
table. Focal length is arranged by source image
distance, SID = 100 cm. Barracuda detector is
connected to computer system, the photo multipled
detector (PMD) sensor of Barracuda connection is
lied on the patient table for measuring the ray from
above Xray tube which is placed inside the selected
field size, and six exposures were made.
Measurement of Xray radiation is setted by
arrangement of voltage (KV) tube,
current
electricity (mA) and exposure time (mS) in the
display of X-ray machine. Meanwhile, Barracuda
detector measure the physical paramater such as:
voltage (KV), exposure time (mS), exposure dose
(mGy), exposure dose rate (mGy/S), and Half Value
Layer (HVL) in mm Al, and other parameters we
need.
Data processing is used to calculate the KV
accuracy, current linearity coefficient (CL),
reproducibility or coefficient variation (CV) by
deviation standar per rate of KV, time, and exposure
dose, respectively, as well as HVL (mm Al) values.
The techniques of processing data were calculated
by formulation on base teory of above section 2, to
derive the standard value of IAEA, BAPETEN
regulation.
3.RESULT AND DISCUSSION
3.1 Lianerity Measurement of radiation
output.
Current linearity is one of physical parameter
that was required by PERKA nu. 9th, 2011
Regulatory Agency of Indonesia. Analizing the
current linearity coefficient is intended to control the
consistency of radiation output [mGy/mAs]. The
measurement located in Haji, Bhayangkara, and Jala
Ammari Navi hospital, respectively. Table 1 shows
the sample of exposure radiation in Haji hospital
using detector of Barracuda measuring tools. The
tools detected exposure time, radiation exposure
(mGy), the sample of radiation measurement is
carried out six times such as follows:
TABLE 1. Measurement of X-Ray machine in Haji
Hospital.
Nu.
1
2
3
4
5
6
7
Exposure
Time
(S)
0.05696
0.06049
0.06452
0.06049
0.06452
0.06345
Tube
Current x
Exposure
Time
(mA.S)
Exposure
(mGy)
1.82272
0.08259
1.93568
0.08334
2.06464
0.08351
1.93568
0.08336
2.06464
0.08348
2.0304
0.08302
CL = 0.05689
Exposure
Rate /
Current tube
(mGy/mA.S)
0.04531
0.04305
0.04045
0.04307
0.04043
0.04089
Measurement of X-ray machine such as in
Table 1 was settled in tube voltage of 70 KV and
tube current was 32 mA source to detector distance
(SID) 100 cm. The calculation of current linearity
coefficient using formulation in equation (1) was
derived CL = 0,05689. This value lower then the
standard for PERKA nu. 9th, 2011 Regulatory
Agency of Indonesia is CL ≤ 0.1. This result shows
that current linearity of X-ray tube in Haji Hospital
in good condition.
Meanwhile, the current linearity of X-ray
radiography in Bhayangkara Police hospital was
measured such as in Table 2. The result value of
current linearity coefficient (CL) was 0.00665. It
means that current linearity fulfilled at CL≤ 0.1, here
is a significant of stable current tube.
TABLE 2. The X-ray radiation
Bhayangkara Police Hospital.
Nu.
1
2
3
4
5
6
7
Exposure
Time
(S)
0.049
0.064
0.079
0.100
0.125
0.159
Tube
Current x
Exposure
Time
(mA.S)
measurement
Exposure
(mGy)
4.939
0.227
6.401
0.293
7.912
0.366
10.030
0.458
12.450
0.574
15.930
0.734
CL = 0.00665
in
Exposure Rate
/ Current
(mGy/mA.S)
0.046
0.046
0.046
0.046
0.046
0.046
On the contrary, the calculation of current linearity
coefficient (CL) of X-ray radiation in Jala Ammari
hospital was 0.25465 such as in Table 3. The value
is greater than 0.1. It indicates that current linearity
is unstable condition, in this case, the X-ray machine
of Jala Ammari has to be calibrated. This is a point
The 3rd International Conference on Theoretical and Applied Physics 2013
and Simposium Fisika Nasional XXVI.
October, 10-11, 2013 Malang, East Java, Indonesia
of quality control of radio diagnostics instrument for
medical physics.
3.2
TABLE 3. Measurement of X-ray radiation in
Jala Ammari Navy Hospital.
Exposure
Time
(S)
Nu.
1
2
3
4
5
6
7
0.5947
0.5932
0.5942
0.5952
0.5952
0.5932
Tube
Current x
Exposure
Time
(mA.S)
Exposure
(mGy)
of
The step up consideration of X-ray machine is to
analyze the reproducibility in three hospitals as
considered above. Determination of reproducibility
using formulation in equation (2). Reproducibility or
variation coefficient (Cv) is defined by deviation
standard per means value of parameter measured,
i.e., exposure time [ms], voltage [KV] dose out put
of X-ray machine. This measurement is arranged at
even voltage of 70 Kv, SID 100 cm. Table 4 shows
the experimental results of X-ray dose out put in
three hospitals as follows:
Exposure
Rate /
Current
(mGy/mA.S)
59.47
2.551
59.32
2.663
59.42
2.589
59.52
2.575
59.52
2.644
59.32
1.582
CL = 0.25465
Reproducibility measurement
radiation out put
0.04290
0.04489
0.04357
0.04326
0.04442
0.02667
TABLE 4. Reproducibility value of X-ray radiation in tube voltage (kV), exposure time (mS) and Exposure (mGy) in Haji,
Bhayangkara and Jala Ammari Navy hospital, respectively.
JALA AMMARI NAVY
HAJI HOSPITAL
BHAYANGKARA HOSPITAL
HOSPITAL
Nu
Tube
Voltage
setted
(KV)
Tube
Voltage
measured
(KV)
Exposure
Time
(mS)
Exposure
(mGy)
Tube
Voltage
measured
(KV)
Exposure
Time
(mS)
Exposure
(mGy)
Tube
Voltage
measured
(KV)
Exposure
Time
(mS)
Exposure
(mGy)
1
70
68,29
44,36
0,0512
69,67
99,79
0,4585
66,17
594,7
1,124
2
70
68,18
36,30
0,1026
69,78
99,75
0,4587
67,13
593,2
1,585
3
70
68,13
44,36
0,0518
69,86
98,27
0,4580
66,25
594,2
1,545
4
70
68,00
40,33
0,0516
69,71
98,77
0,4592
66,24
595,2
1,537
5
70
68,43
56,46
0,0813
69,83
99,28
0,4569
66,70
595,2
1,578
6
68,38
0,16288
36,62
7,54345
0,1015
0,02505
69,77
0,07127
100,3
0,74340
0,4581
0,00078
66,58
0,36918
593,2
0,91742
1,582
0,18133
8
70
Deviation
Standard
Rate
68,21
44,362
0,0733
69,77
99,36
0,458
66,512
594,283
1,492
9
Cv
0,00239
0,17004
0,34165
0,00102
0,00748
0,00171
0,00555
0,00154
0,12155
7
PERKA nu. 9th, 2011, regulatory agency of
Indonesia gave requirement value for reproducibility
Cv less then 0.05. The Cv values in Table 4 show
that in haji Hospital, exposure time (mS) and
exposure dose (mGy) were 0.17004, and 0.34165
respectively, the values are more then that required.
Here is needed to calibrate the exposure time and
exposure dose of X-ray tube machine in Haji
hospital. Meanwhile, measurement of tube voltage,
exposure time and dose radiation in Bhayangkara
Hospital were derived Cv values less then of 0.05.
The examine is accepted. Furthermore, in Jala
Ammari Navy hospital, it was measured Cv =
0,12155 for exposure dose radiation, It shows the value
more then that requirement, and other parameters of
voltage, and exposure time is accepted by PERKA nu.
9th, 2011and IAEA.
3.3
Half
Value
Measurement
Layer
(HVL)
Half value layers (HVL) measurement is intended to
attenuate 50% of incident energy from radiation
source by using shelding material in vocal spot of Xray machine. The thickness of material has an
ability to prevent the hazard of soft X-ray, by
The 3rd International Conference on Theoretical and Applied Physics 2013
and Simposium Fisika Nasional XXVI.
October, 10-11, 2013 Malang, East Java, Indonesia
reducing the surface doses during X-ray imaging.
Measuring of HVL value uses the Aluminium
material in mmAl unit. There were exemined the
HVL (mmAL) of three hospitals such as in Table 5.
It shows that HVL value raises when the voltage is
increased. Voltage variation is needed to exemine
the HVL value. IAEA and PERKA nu. 9th, 2011
required the HVL value in 70 KV is above 2.3 mm
Al. In this case, The exemining in Haji hospital,
HVL value was 2.38 mmAl of 50 KV setted or
49.68 KV measured, and in 70 KV was 3.21 mmAl.
the value is bigger then the required by IAEA, while
it is accepted value or normal condition.
2. The International standard for physical parameter
of Xray machine is regulated by the International
atomic energy agency (IAEA), and Nuclear
Energy Regulatory Agency of Indonesia such as
in PERKA BAPETEN Nu: 9th, 2011. Parameter
value is accepted reproducibility (Cv) ≤ 0.05,
current linearity coefficient (CL) ≤ 0.1, and HVL
in mm-Al ≥ 2.1 mm-Al of 70 kV, respectively.
3. The analysis results of reproducibility (CV),
linearity (CL) and HVL values, respectively, for three
hospital showed that Xray machine in Jala
Ammari is not acceptable of regulation, it is needed
for calibration. On the contrary, the all parameter
values in Bhayangkara hospital were accepted in good
condition. And Haji hospital is agree with regulation,
accept the reproducibility value was 0.3417 for
exposure output dose and CV for exposure time was
0.170, and it is recomended for calibration.
TABLE 5. HVL Measurement of each measured Voltage
of X-ray machine.
BHAYANGKAR
A HOSPITAL
HAJI HOSPITAL
JALA AMMARI
HOSPITAL
Nu
VS
(KV)
MV
(KV)
HVL
MV
(KV)
HVL
MV
(KV)
HVL
1
50
49,68
2.38
49.74
1.87
47.87
1.57
2
60
58.09
2.65
59.79
2.05
57.22
1.71
3
70
68.26
3.21
69.78
2.58
71.72
2.18
4
70
68.29
3.19
69.90
2.58
67.13
2.01
5
70
68.18
3.21
69.82
2.59
6
80
77.22
3.60
79.83
2.98
66.70
-
2.0
-
Where: VS is Voltage setted (KV),
MV is Measured Voltage (KV)
Furtheremore, HVL (mm-Al) checking in
Bhayangkara Hospital was derived of 2.58 mmAl in
70 KV, this value is accepted condition. Meanwhile,
for Jala Ammari X-ray machine, it is exemined the
HVL = 2.18 mm Al in 70 KV, this value is less then
from IAEA requirement. This is to considerate that
the value of HVL parameter on this X-ray machine
is proposed for calibration.
CONCLUSION
1. The measurement of physical parameter of X-ray
radiation in each Hospitals is one of quality
control to investigate some factors affecting on
quality assurance of X-ray machine, such as
tube voltage (kV), exposure time (mS), X-ray
exposure (mGy), exposure rate (mGy/S), and
Half Value Layer (HVL).
ACKNOWLEDGEMENTS
The writer wishes many thanks to Minister for
Education and Culture, Rector of Hasanuddin
University, and chairman of research center,
Hasanuddin University for the sponsorship using
operational funding for State University (BOPTN),
2013.
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