Journal of Biosciences and Medicines, 2014, 2, 17-21
Published Online April 2014 in SciRes.
How to cite this paper: Komarskiy, A.A., et al. (2014) Reducing Radiation Dose by Using Pulse X-Ray Apparatus. Journal of
Biosciences and Medicines, 2, 17-21.
Reducing Radiation Dose by Using Pulse
X-Ray Apparatus
A. A. Komarskiy1,2, A. S. Chepusov1,2, V. L. Kuznetsov1, S. R. Korzhenevskiy1, S. P. Niculin1,2,
S. O. Cholakh2
1Pulsed Radiation Sources Laboratory, The Institute of Electrophysics of the Ural Division of the Russian
Academy of Science, Ekaterinburg, Russian Federation
2Institute of Physics and Technology, Ural Federal University (Named after First President of Russia B.N. Yeltsin),
Ekaterinburg, Russian Federation
Received December 2013
Pulse X-ray diagnostics is capable of reducing the radiation exposure considerably. As for pulse
X-ray diagnostic machines, which form pulses with the duration of 0.1 µs, using them one can get
outstanding results in this area. This fact can be explained by the long period of luminophor per-
sistence in intensifying X-ray luminescent screens. In this paper we present experimental data,
comparing radiation doses, measured at pulse X-ray apparatus and apparatus of constant radia-
X-Radiation; Pulse X-Ray Tube; Pulse X-Ray Diagnostic; Ionizing Radiation
1. Introduction
Medical radiation makes up a major portion of the radiation dose for population of the Earth. As for the Russian
Federation this type of radiation takes the second place after natural sources of ionizing radiation in the total
radiation doze. 98% of the radiation is taken by diagnostic and prophylactic X-ray examinations.
Pulse X-ray diagnostics is capable of reducing the radiation exposure considerably. Generating X-ray radia-
tion as a sequence of short X-ray flashes instead of continuous radiation is a distinguishing feature of this me-
thod. The pulse X-ray tube (pulse duration 5 - 20 ms, frequency 2 - 12 pulses per second), which is used during
endoscopic diagnostic and therapeutic interventions of bile ducts, was described in paper [1]. The shorter the
pulse and the less the frequencythe less the radiation exposure of the patient and the personnel, but the quality
of the images reduces accordingly.
As for pulse X-ray diagnostic machines, which form pulses with the durations of 0.1 µs, the principle of re-
ducing the absorbed dose is completely different.
2. Experiment
In medical diagnostics intensifying X-ray luminescent screens are obligatory. Since X-ray film, which most
A. A. Komarskiy et al.
commonly used to absorbed radiation has coefficient of X-ray radiation 0.01, as for intensifying screens
Gd2O2S:Tb the coefficient is 0.29 [2]. Luminophors, which are used in the intensifying screens, have a certain
period of persistence [3].
To define the duration of persistence precisely timing data and fluorescence intensity of luminophors, used in
diagnostics, Kodak lanex, Renex EU-G3, Renex EU-G300, Renex EU-I4, were measured. Measuring was per-
formed at a pulsed cathodoluminescence spectrometer. In Figure 1, you can see an oscillogram, picturing the
process of luminophor persistence Renex EU-G3, typical for all the group of intensifying screens under investi-
gation. The persistence duration of level 2.7 is 500 µs when pulse duration is 0.1 µs.
The final results as persistence duration of the intensifying screens of level 0.1 are given in Figure 2.
Measuring amplitude-time characteristics of persistence show, that all luminophors under investigation are
characterized by the persistence at level of a millisecond, which is by an order of magnitude greater than radia-
tion pulse duration of a nanosecond X-ray unit, as shown in Figure 3.
X-ray quanta irradiate luminophor the X-ray photo detector luminophor with the intensity Ir, and the lumino-
phor radiation intensity is
ItI e
= ⋅
Figure 1. The persistence X-ray intensifying screen Renex
Figure 2. Persistence duration of the intensifying screens of
level 0,1.
Lane x
A. A. Komarskiy et al.
Figure 3. An oscillogram of voltage and current of the X-ray
tube RIA1-120. Voltage amplitude—110 kV, current ampli-
tude—450 А, scale 10 ns/ point, repetition rate 850 Hz.
where Il(t) is the radiation intensity at the time t, τ is the average time during which the excited state of lumino-
phor atoms or molecules persists, T is period, I0 is radiation intensity at the time when excitation of lumines-
cence stops
(0.2 0.01)
when using a constant X-radiation source, luminophor generates light radiation with the intensity I0 and a per-
sistence fall after X-ray exposure in е times within (1 1.5)*103 (s) during the whole time of exposure from
hundreds of milliseconds and higher. At pulse radiation after X-ray pulse exposure luminophor persistence cor-
responds to е times during the same time, but this process repeats after each pulse. In the result of X-ray film
accumulating light sum of the X-radiation, converted by luminophor, after X-ray pulse stops, the great differ-
ence in duration of the X-ray pulse and the luminophor persistence fall makes it possible to reduce the exposure
dose. At the Institute of Electrophysics of the Ural Division of the Russian Academy of Science we invented the
pulse X-ray diagnostic portable apparatus 01 (XDPA 01) [4], which was based on the described effect. Then we
upgraded the X-ray apparatus and created the pulse X-ray diagnostic portable apparatus Yasen-01 [5] [6].
We performed dosimetric tests, comparing the pulse X-ray diagnostic portable apparatus Yasen-01 (maximum
voltage is 110 kV, the tube’s current is 150 A, pulse duration is 30 ns, repetition rate is 5 kHz) with the X-ray
diagnostic apparatus Siemens Axiom Iconos R200 (maximum voltage is 125 kV), using a direct current tube.
Measuring dosimetric parameters was carried out with the help of the dosimeter PTW UNIDOS 10001 with
30 cm3 cylindrical ionization chamber of 23361 kinds. Several standard modes of the tested machines for medi-
cal diagnostics of different body organs were chosen. The main criterion for the comparison was the diagnostic
quality of the X-ray photographs, as shown in Figure 4.
Water phantom was used behind the ionization chamber to imitate a human body (as a scattered radiation
source). Phantom thickness was 20 cm, focal distance to the ionization chamber was 80 cm. The results of in-
vestigations are shown in Table 1.
Then we performed tests, comparing the pulse X-ray apparatus Yasen-01 with the X-ray portable diagnostic
apparatus Definium AMX 700 (maximum voltage is 105 kV) and with stationary X-ray complex Evolution HV
which was created by STEPHANIX (maximum voltage is 40 - 150 kV). We compared the following parameters:
effective doses, the quality of the X-ray images and usability.
Calculating the effective doses of patients was made using the results of measuring radiation output of the
apparatus with the help of the following measuring devices: the wide-range device for dosimetry of continuous
and pulse X-rays and gamma rays DKS-AT1123, the all-mode dosimeter for controlling characteristics of X-ray
apparatus-Unfors Xi RF&MAM detector. In Table 2, effective doses of patient irradiation are presented.
Three proficient roentgenologists carried out independent estimation of the X-ray images’ quality and the ap-
paratus’ usability.
A. A. Komarskiy et al.
(a) (b)
Figure 3. Elbow arthrogram using by a) X-ray diagnostic apparatus with direct current tube; b) pulse X-ray
diagnostic portable apparatus Yasen-01.
Table 1. Test results of Siemens Axiom Iconos R200 and Yasen-01.
Object, projection Siemens Axiom Iconos R200 Yasen-01
Voltage, kV Exposition, mAs Dose, µGy Voltage, kV Exposition, mAs Dose, µGy
Lungs, direct 57 3.6 200 110 1.4 70
Skull, side 60 8 505 110 3.7 185
Thigh, direct 55 8 410 110 3.4 170
Knee, direct 47 6.3 215 100 1.8 86
Ankle, direct 48 4.5 160 100 1.0 48
Table 2. Effective doses of patient irradiation.
Name Projection Effective dose, mSv
Yasen-01 Chest (direct) 0.027
Definium AMX 700 Chest (direct) 0.570
Evolution HV Chest (direct) 0.721
3. Discussion
As follows from the Table 1, the radiation dose of Yasen-01 is 2.5 - 3 times lower than the one of Siemens
Axiom Iconos R200 and 20 - 25 times lower compared with Definium AMX 700, Evolution HV. The fact is that
with the help of the pulse X-ray we can decrease the dose more significantly can be explained by the higher
value of anode current (Yasen-01 150 A), since luminophor radiation intensity Il is proportional to X-ray
quantum intensity Ir hence it proportional to the X-ray tube current Ie. Moreover, decreasing dose is explained by
pulse duration: the Yasen-01 apparatus generates X-ray pulses of shorter duration (30 ns). Therefore the Ya-
sen-01 apparatus has a more homogeneous radiation spectrum and greater effective energy (42.5 keV), i.e. it
A. A. Komarskiy et al.
creates harder radiation. The X-ray tube’s performance in good conditions in terms of maximum acceptable heat
load of the anode should be considered as one of the machines’ advantages. At present the operating mode of
constant radiation machines is limited to 0.3 - 0.01 A. This limitation is subject to maximum acceptable heat
load of the anode, since exceeding this value causes anode destruction. However the pulse tube current reaches
the peak value of 150 А, which increases luminescence intensity Il by dozens of times. For example, if repetition
rate is f = 1 kHz and pulse durations is τ = 108 s, duty factor
equals Q = 105, and the tube average current < I > (when current pulse is Ie = 100 А) is inversely proportional to
pulse duty factor,
< >=
( 4)
and equals just < I > = 1 × 103А.
The chest X-Ray direct projection images, which were obtained at the pulse X-ray diagnostic portable appa-
ratus Yasen-01, are the same as to the quality of the images, which were obtained by the X-ray portable diag-
nostic apparatus Definium AMX 700 and are insignificantly inferior compared with the images obtained by the
stationary X-ray complex Evolution HV which was created by STEPHANIX.
Roentgenologist point out that thanks to the compact size and low weight (about 45 kg) the Yasen-01 appara-
tus can be used in confined space and is easily transported.
4. Conclusions
In conclusion, the conducted investigation demonstrates that X-ray radiation dose is decreased by several times
thanks to using pulsed nanosecond X-ray machines as opposed to using relative conventional X-ray units. The
dose of radiation was reduced so significantly thanks to the fact that persistence duration of X-ray radiation
converters (luminophor) is several times higher than X-ray pulse duration.
Further decreasing radiation dose is possible owing to increasing current pulse amplitude Ie, shortening pulse
duration τ and increasing duty factor Q.
The quality of the X-Ray images which were obtained at the pulse X-ray diagnostic portable apparatus Ya-
sen-01 is the same as at constant X-radiation apparatus. Thanks to its small size and weight Yasen-01 apparatus
can be used in confined space and easily transported in narrow corridors and elevators.
[1] Doroshko, M. V. (1998) New Capabilities in Reducing of Radiation Dose лу чев ой нагрузки. News of Radiodiagnos-
tics, 3, 13-15.
[2] Blinov, N.N., Bikov, R.E. and Kozlovskiy, E.B. (1989) Engineering Tools of Medical Introscopy. Leonov B.I.,
[3] Kazgikin, O.N., Markovskiy, L.Y., Mironov, I.A., Pskerman, F.M. and Petoshina, L.N. (1975) Inorganic Phosphor.
[4] Filatov, A.L., Korzhenevskiy, S.R., Kuznetsov, V.L., Ananin, M.V. and Motovilov, V.A. (2004) The Nanosecond PP
X-ray Apparatus. Procedings of the 15th International Conference on High-Power Particle Beams, Saint-Petersburg,
1-7 April 2004, 552-554.
[5] Filatov, A.L., Bastrikov, V.L., Korzhenevskiy, S.R., Kuznetsov, V.L. and Ponikaravskih, A.E. (2007) Universal Porta-
ble X-Ray Apparatus. Russian Federation Patent No. 2005503167.
[6] Mozharova I.E. and Kuznetsov V.L. (2011) The Pulse X-Ray Diagnostic Portable ApparatusYasen 01”. Medical
business, 9, 84-85.