Facility for the electromagnetic hyperthermia based on the phased array
Hyperthermia is a promising approach to improve of the chemo- and the radiotherapy efficiency by means of increasing tumor’s temperature. Hyperthermia is an additional method to conventional treatments of oncological disease wherein tumor temperature is increased up to 40…43°C. The phased array of a...
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України
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| Cite this: | Facility for the electromagnetic hyperthermia based on the phased array / A.M. Fadeev, S.M. Polozov, E.A. Perelstein, S.M. Ivanov // Вопросы атомной науки и техники. — 2013. — № 6. — С. 220-224. — Бібліогр.: 8 назв. — англ. |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine| _version_ | 1860161137175166976 |
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| author | Fadeev, A.M. Polozov, S.M. Perelstein, E.A. Ivanov, S.M. |
| author_facet | Fadeev, A.M. Polozov, S.M. Perelstein, E.A. Ivanov, S.M. |
| citation_txt | Facility for the electromagnetic hyperthermia based on the phased array / A.M. Fadeev, S.M. Polozov, E.A. Perelstein, S.M. Ivanov // Вопросы атомной науки и техники. — 2013. — № 6. — С. 220-224. — Бібліогр.: 8 назв. — англ. |
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| container_title | Вопросы атомной науки и техники |
| description | Hyperthermia is a promising approach to improve of the chemo- and the radiotherapy efficiency by means of increasing tumor’s temperature. Hyperthermia is an additional method to conventional treatments of oncological disease wherein tumor temperature is increased up to 40…43°C. The phased array of applicators for electromagnetic hyperthermia was suggested earlier. The heating is provided by absorption of electromagnetic energy focused in tumor by varying phases and amplitudes of each of dipoles. Operating frequency plays the significant role in specific absorption rate (SAR) distribution forming. The phased array antenna is under consideration. Principles of choosing of operating frequency are discussed. Numerical estimates of heat localization depending on the radiation area are presented. Also simulation results with voxel model are considered.
Гіпертермія є багатообіцяючим способом для збільшення ефективності хіміо- і променевої терапії за допомогою підвищення температури пухлини. Гіпертермія − додатковий до традиційних метод лікування онкологічних захворювань, при якому відбувається підвищення температури пухлини до 43...44°C. Фазований масив випромінювачів для електромагнітної гіпертермії був запропонований раніше. Нагрівання забезпечується поглинанням електромагнітної енергії, сфокусованої в пухлині при зміні фаз і амплітуд хвиль, що генеруються кожним з випромінювачів. Частота випромінювання відіграє значну роль у формуванні розподілу питомого коефіцієнта поглинання (ПКП). Розглядається фазований масив випромінювачів. Обговорюються принципи вибору робочої частоти. Представлено чисельні оцінки локалізації нагрівання залежно від області опромінення. Також розглянуто результати моделювання з використанням воксельних моделей.
Гипертермия является многообещающим способом для увеличения эффективности химио- и лучевой терапии посредством повышения температуры опухоли. Гипертермия – дополнительный к традиционным метод лечения онкологических заболеваний, при котором происходит повышение температуры опухоли до 43…44°C. Фазированный массив излучателей для электромагнитной гипертермии был предложен ранее. Нагрев обеспечивается поглощением электромагнитной энергии, сфокусированной в опухоли при изменении фаз и амплитуд волн, генерируемых каждым из излучателей. Частота излучения играет значительную роль в формировании распределения удельного коэффициента поглощения (УКП). Рассматривается фазированный массив излучателей. Обсуждаются принципы выбора рабочей частоты. Представлены численные оценки локализации нагрева в зависимости от области облучения. Также рассмотрены результаты моделирования с использованием воксельных моделей.
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| first_indexed | 2025-12-07T17:55:00Z |
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ISSN 1562-6016. ВАНТ. 2013. №6(88) 220
FACILITY FOR THE ELECTROMAGNETIC HYPERTHERMIA
BASED ON THE PHASED ARRAY
A.M. Fadeev1, S.M. Polozov1, E.A. Perelstein2, S.M. Ivanov1,3
1National Research Nuclear University “Moscow Engineering Physics Institute”,
Moscow, Russia;
2Joint Institute for Nuclear Research, Dubna, Moscow region, Russia;
3Russian Oncological Research Center named after N.N. Blokhina RAMC, Moscow, Russia
E-mail: SMPolozov@mephi.ru
Hyperthermia is a promising approach to improve of the chemo- and the radiotherapy efficiency by means of in-
creasing tumor’s temperature. Hyperthermia is an additional method to conventional treatments of oncological dis-
ease wherein tumor temperature is increased up to 40…43°C. The phased array of applicators for electromagnetic
hyperthermia was suggested earlier. The heating is provided by absorption of electromagnetic energy focused in
tumor by varying phases and amplitudes of each of dipoles. Operating frequency plays the significant role in specif-
ic absorption rate (SAR) distribution forming. The phased array antenna is under consideration. Principles of choos-
ing of operating frequency are discussed. Numerical estimates of heat localization depending on the radiation area
are presented. Also simulation results with voxel model are considered.
PACS: 87.54.B
INTRODUCTION
Hyperthermia is a method of cancer treatment by
means of increasing tumor temperature up to 40…44°C.
Hyperthermia is usually applied in oncology as an ad-
junct to the traditional methods. Under specific condi-
tion established treatment methods such as radiotherapy
and chemotherapy are less effective. Hyperthermia
makes tumor cells be more sensitive to the radiation and
to the anticancer drugs. Many researches have shown
that high temperature can damage and even kill tumor
cells. The effect on surviving fraction depends both on
the magnitude of the temperature and on the duration of
the expose. Experimental studies show that tumor cell
heating alone for 60 minutes at 43°C is damaging and
that the period of exposure decreases by a factor of two
for each increasing degree in temperature above approx-
imately 43°C [1, 2]. So, 60-minute hyperthermia treat-
ment at 43°C can be replaced by 15-minutes treatment
at 45°C. The main mechanism for cell death is probably
protein denaturation, observed at temperatures above
40°C, which leads to alternations in multimolecular
structures such as cytoskeleton and membranes, and
changes in enzyme complex for DNA synthesis and
repair [3]. Also heat enhances the cytotoxicity of X-rays.
Increased cytotoxicity observed over and above what
would be expected on the basis of additivity of the two
treatments, and it is maximized when these are given
simultaneously. It decays with time when the treatments
are separated by more than one or two hours [4].
The thermal therapy combined with the radiation
(thermoradiotherapy, TRT) has been applying in
N.N. Blokhin Russian Oncological Research Center
(RORC) since 1980-th. More than 1000 patients have
been treated up to now. Data presented in [5] demon-
strate better efficiency of TRT than the radiation therapy
applied alone. The complete tumor regression rates
higher after combined treatment.
Also high temperature damages the healthy tissues
and one of the most important problems of the hyper-
thermia technique is to prevent the overheating of these
tissues. Various mechanisms for cell killing by heat
have been proposed. But non-invasive heating of deep
seated tumors is a difficult technique challenge. In this
case the electromagnetic field has an advantage over
other methods of physical expose (for instance, ultra-
sound) to create higher level temperature in a given vol-
ume of tissue. Radio frequency (RF) fields have a great-
er penetration rate than optic or infrared waves. Using
the single applicator to heat tumors located deeper than
2…3 cm is not effective method. The most evident ap-
proach to reach deep-seated tumors is using an array of
applicator situated around the patient body [6]. It should
be a phased array to steer maximum of absorption pow-
er in patient body. Optimized distribution is reached by
varying of the amplitudes and the phases of waves pro-
duced by each applicator. As a result of the constructive
interference of E-field in the focus region, multichannel
phased array of applicator can provide deeper penetra-
tion level of RF energy without overheating of skin and
superficial healthy tissues.
1. THE PHASED ARRAY
Suggested phased array consists of eight copper di-
poles, attached on the inner side of the dielectric cylin-
der, and surrounds a patient body. Top view of this
structure is shown in Fig. 1,a. The aperture radius is up
to 60 cm which can be applied in more cases. Dipoles
are fed independently permitting to control phases and
amplitudes of waves produced by each dipole. Space
between the dipoles and the patient body is filled by
deionized water (conductivity σ ≈ 0.001). Thus applica-
tors are squeezed from the inner side by lossy medium
with high permittivity (deionized water ε ≈ 80), and
from the outer side by medium with low permittivity
(air ε=1). The conducting elements of antenna are iso-
lated from lossy medium by thin layer of an insulator
(thickness h ≈ 1 mm). Because of energy density of
electrical fields (1/2 ED) inside the dielectric tank is
higher by a factor of ε (the relative dielectric constant of
medium) than in the air outside, energy is mainly con-
centrated inside the array. Fig. 1,b,c care presented to
demonstrate SAR distributions, which produced in a
muscle tissue cylinder (conductivity at 150 MHz σ=
ISSN 1562-6016. ВАНТ. 2013. №6(88) 221
0.73 S/m and relative permittivity ε = 72.2) with diame-
ter of 200 mm. Space between the muscle cylinder and
the phased array is filled with deionized water (see
Fig. 1,b) and with air (see Fig. 1,c). These distributions
have similar behavior, but SAR value, produced in the
phased array filled with deionized water, is substantially
greater than without water because in the second case
one side of each dipole has a contact with water. The RF
field components in water are in ε times intensive than
in air. SAR ratio is about 200. Thus deionized water not
only cools body surface and superficial tissues but is
also a matching medium.
Fig. 1. Top view of phased array surrounding patient
body (a); SAR distributions are produced in the phased
array filled with deionized water and (c) with air space
between dipoles and patient body (b)
Detailed scheme of dipoles including sizes is depict-
ed in Fig. 2. Half of dipole is shown because of sym-
metry. In this picture two horizontal segments of anten-
na (signed as Lh) form two-conducting transform line
that guides RF power to the vertical section (Lv). Verti-
cal sections are radiating elements and horizontal seg-
ments contribution to the E-field canceled everywhere
except proximity to the copper elements. Moreover ver-
tical parts of antenna, insulation layer and lossy medium
with high permittivity can be considered as a microstrip
transmission line.
Electric fields lines are parallel to the axis of dipoles
inside the phased array. As it known heat absorption is
proportional to tissue conductivity (σ, which value for
fat are significant lower than for muscle or tumor tis-
sue). Thus overheating of skin and superficial tissues is
reduced in comparison with using of capacitive applica-
tors.
Fig. 2. Detailed scheme of dipole with dimensions (a);
Cross-section view of radiating part of dipole (b)
Ez is the only component which able to control by
shifting the amplitudes and phases of eight dipoles.
E-field generated by each of the dipoles is given by:
( ) ( )0 , expj j j jE A E x y i t = − ω −Φ , (1)
where 0jE – is the complex E-field for 1, 0j jA = Φ = ,
and 0kA = for j k≠ . jA – is a scaling factor of ampli-
tude, jΦ – wave phase, j and k – are numbers of di-
poles. It is able to move peak of interference pattern and
to focus it into the tumor site with the variation of these
two parameters (phase and amplitude). The measure of
the rate at which energy is absorbed by the body when
exposed to a radio frequency (RF) electromagnetic field
is a Specific Absorption Rate (SAR). It is defined as the
power absorbed per mass of tissue and has units of watts
per kilogram (W/kg):
2ESAR σ
ρ
=
, (2)
where σ – is the electrical conductivity of the tissue
(S/m), ρ – is the density of the tissue (kg/m3), E – is the
root mean square electric field.
2. SIMULATION RESULTS
To demonstrate that the phased array can produce a
maximum SAR distribution inside patient body, radia-
tion simulations were performed. The simulations are
performed with CST Microwave Studio. In previous
report [7] SAR focusing ability was presented. Simula-
tions were performed with limbs. The phase array can
be used for different regions of patient body, but differ-
ent regions require determining the optimal frequency
a
b
c
a b
ISSN 1562-6016. ВАНТ. 2013. №6(88) 222
range. For this purpose neck model was used and it is
shown in Fig. 3. The model is a muscle cylinder of di-
ameter 150 mm. Trachea filled by air, cartilage, spinal
chord, bone and tumor are included in this model. The
tumor is situated as more as deeper but not in the center
of model to demonstrate focusing ability of absorbed
power. Simulations were performed for two operating
frequencies: 150 and 434 MHz. The simulations are
performed also with CST Microwave Studio. Simula-
tion results are presented in Fig. 4. Cross section SAR
distributions with the coherent feeding of antennas are
depicted in Figs 4,a,c, the optimized SAR distributions
with relative phases are given in Figs 4,b,d.
Fig. 3. Neck model used for simulation
Optimized SAR distributions are achieved with var-
ying both the phases and the amplitudes of produced
waves. The phases were chosen by the principle that the
peak SAR shifts away from the dipole which has phase
delay. The relative values of the phases and the ampli-
tudes are noted opposite to each dipole. In this case not
only phases varying are necessary due to presence of the
bone tissue (ε=14.41; σ=0.07 at 150 MHz) and air filled
trachea(ε=1; σ=0) in the center of the model. For coher-
ent feeding at 150 MHz the peak SAR is situated in the
muscle and tumor tissues around the low conductive and
higher dense bone tissue (see Fig. 4,a). The penetration
depth of electromagnetic fields at 150 MHz is greater
than it necessary because the great volume of muscle
tissue in the pattern of the optimized SAR absorbs too
much power (see Fig. 4,b). As known the higher wave
frequency, the higher tissue conductivity and the lower
penetration depth, so simulation with operating frequen-
cy of 434 MHz was performed. When antennas fed co-
herently the peak SAR is situated, as in case of operat-
ing frequency of 150 MHz, in the muscle tissue (see
Fig. 4,c), but the value of the peak SAR at 434 MHz is
higher than at 150 MHz. The optimized SAR distribu-
tion is reached by means of varying both the phases and
the amplitudes which are noted opposite the each anten-
na, and it is presented in Fig. 4,d. The good focusing of
absorbed power in the tumor tissue is depicted in
Fig. 4,d. Also the majority part of the healthy tissues is
staying at normal temperature range. Thus the tumor
localization size is 20…30 mm without overheating of
the healthy tissues at 434 MHz for the neck model. For
example, 40…50 mm localization size for limbs and
10…20 mm for the breast were reached during simula-
tions (not presented in this paper).
Fig. 4. SAR distribution with the coherent feeding at
150 MHz (a); optimized SAR distribution at 150 MHz
(b); SAR distribution with the coherent feeding at
434 MHz (c); optimized SAR distribution at 434 MHz (d)
3. SIMULATION WITH VOXEL MODEL
A voxel (volumetric pixel) is a volume element, rep-
resenting a value on a regular grid in three dimensional
space. This data point can consist of a single piece of
data, such as opacity, or multiple pieces of data. The
value of a voxel may represent various properties. In CT
scans, the values are Hounsfield units, giving the opaci-
ty of material to X-rays. Different types of value are
acquired from MRI or ultrasound. After scanning the
model is reconstructed. The voxel model of human body
including 86 different tissues is presented in Fig. 5,d.
Such parameters like dielectric and thermal properties,
densities can be assigned to the each tissue [8]. Thereby
a
b
c
d
ISSN 1562-6016. ВАНТ. 2013. №6(88) 223
the most accurate simulation can be performed by using
voxel models. To demonstrate that the phased array can
produce a maximum SAR distribution inside patient
body in desirable region, radiation simulations with dif-
ferent operating frequencies were performed. The mate-
rial properties of water shell, enclosure and antennas are
also included in simulation. The blood flow and the
thermal conductivity aren’t factored in the simulation,
thus the simulated pattern of SAR distribution have lo-
cal maximum within vessels. The real SAR distribution
hasn’t these locals.
Fig. 5. Cross-section pattern of the SAR distribution
with different operation frequencies (a) 150 MHz; (b)
100 MHz; (c) 80 MHz and with input phases of 50°, 50°,
50°, 50°, 0°, -30°, -40°, -10° applied to channels
1,2…8 respectively; (d) cross-section of the voxel model
There are three operating frequencies were used for
SAR simulation: a) 150 MHz; b) 100 MHz; c) 80 MHz.
Unfortunately, this model doesn’t include the tumor
tissue. Phases of each dipole were changed for estimat-
ing focusing ability in any region of the body. The liver
was selected as a focus region (marked as blue on
Fig. 5,d). Also we tried to minimize absorption rate in
other soft tissues. Cross-section SAR distributions with
relative phases are depicted on Fig. 5. The simulated
focus is steered to the liver with input phases of 50°,
50°, 50°, 50°, 0°, -30°, -40°, -10° applied to channels
1,2…8 respectively. Also the goal was to prevent occur-
ring hot spots in other regions and to maximize the SAR
value in relative to the healthy tissue SAR. The phases
were chosen by the principle that the peak SAR shifts
away from the dipole which has phase delay, i.e. the
peak SAR will be shifted away from the dipole #3 due
to the phase delay on this dipole will be 50°. Ampli-
tudes were not varied.
In the case of optimized SAR distribution the maxi-
mum SAR value was observed with the operating fre-
quency of 100 MHz, and the minimum SAR value – of
80 MHz (see Fig. 5,b,c). This means that SAR distribu-
tion with lower operating frequency is more uniformly
and the peak is specialized weakly. It can be concluded
that the operating frequency of 100 MHz is the optimal
for the voxel model with such transverse size. For mod-
els with greater transverse sizes the using of the lower
operating frequencies is desirable.
The SAR distribution with operating frequency of
100 MHz, depicted on Fig. 5,b, has a peak in a liver site,
and it is more uniform in the area outside the peak in
comparison with other operating frequencies. Local
peaks in other soft tissues (muscle) aren’t appeared. It
seems that the operating frequency 100 MHz is more
preferable for the model of these transverse sizes. How-
ever it is hard to confirm that using of this operating
frequency will be equally effective for the other trans-
verse model sizes. It argues that hyperthermia planning
procedure is necessary for each patient.
CONCLUSIONS
Heating of deep-seated tumors can be realized by
means of focusing of radiofrequency energy inside the
patient body. The phased array is suggested to increase
the temperature level in the tumor side and on the other
hand to prevent overheating of the healthy tissues. Di-
poles geometry was discussed. Differences in the dielec-
tric properties of tumor and healthy tissues play signifi-
cant role in power absorption of RF fields and the voxel
models, based on the real data like computer tomogra-
phy or magnetic resonance imaging, provide the more
accurate simulation of the hyperthermia planning proce-
dure. It is shown that production of desirable SAR dis-
tribution inside the patient body by using the phased
array is possible. By proper selection of phases and am-
plitudes of the waves radiated from each dipole it is
possible to concentrate resulting EM-field in the tumor
site. The phases are choosing by the principle at which
the peak SAR shifts away from the dipole that has a
phase delay. SAR distributions simulation results are
presented and it promising performances are demon-
strated. But the issues deals with the most effective op-
erating frequency are still under discussion by reason of
the different models with different cross sectional di-
mensions comply with relevant penetration depth of the
EM-field. For the used voxel model of abdomen the
a
b
c
d
ISSN 1562-6016. ВАНТ. 2013. №6(88) 224
operating frequency of 100 MHz is optimal. It is sup-
posed that frequency range 60…120 MHz can over-
spread essential dimensional ranges. It is shown that the
heating localization size can be not higher than
20…30 mm without overheating of the healthy tissues
at 434 MHz for the neck model. The phased array proto-
type construction is the further step in our work.
REFERENCES
1. S.B. Field, J.W. Hand. An Introduction to the Prac-
tical Aspects of Clinical ttyperthermia. New York:
Taylor & Francis. 1990, p. 293.
2. S.A. Sapareto, W.C. Dewey. Thermal dose determi-
nation in cancer therapy // lnt J Radiat Oncol Bi-
olPhys. 1984, v. 10, p. 787-800.
3. W.C. Dewey. Arrhenius relationships from the mol-
ecule and cell to the clinic // Int J Hyperthermia.
1994, v. 10, p. 457-83.
4. G.M. Hahn. Hyperthermia and cancer. New York:
Plenum. 1982.
5. S.I. Tkachev, Y.A. Barsukov, S.S. Gordeyev. New
combined treatment regimen for primary unresec-
table locally advanced rectal cancer // Eur. Journal
of Surgical Oncology. 2010, v. 36(9), p. 877.
6. A.M. Fadeev, S.M. Polozov, V.N. Belyaev, et al. RF
Power and Control Systems for Phased Dipoles Ar-
ray System for Hyperthermia // Proc. of RUPAC.
2012, p. 524-525.
7. A.M. Fadeev, S.M. Polozov, S.M. Ivanov, et al. Fa-
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// Problems of Atomic Science and Technology. Se-
ries “Nuclear Physics Investigations”. 2012,
№3(79), p. 191-194.
8. An Internet resource for the calculation of the die-
lectric properties of body tissues,
http://niremf.ifac.cnr.it/tissprop/.
Article received 05.09.2013
УСТАНОВКА ДЛЯ ЭЛЕКТРОМАГНИТНОЙ ГИПЕРТЕРМИИ, ОСНОВАННАЯ
НА ФАЗИРОВАННОМ МАССИВЕ ИЗЛУЧАТЕЛЕЙ
А.М. Фадеев, С.М. Полозов, Э.А. Перельштейн, С.М. Иванов
Гипертермия является многообещающим способом для увеличения эффективности химио- и лучевой те-
рапии посредством повышения температуры опухоли. Гипертермия – дополнительный к традиционным ме-
тод лечения онкологических заболеваний, при котором происходит повышение температуры опухоли до
43…44°C. Фазированный массив излучателей для электромагнитной гипертермии был предложен ранее.
Нагрев обеспечивается поглощением электромагнитной энергии, сфокусированной в опухоли при измене-
нии фаз и амплитуд волн, генерируемых каждым из излучателей. Частота излучения играет значительную
роль в формировании распределения удельного коэффициента поглощения (УКП). Рассматривается фазиро-
ванный массив излучателей. Обсуждаются принципы выбора рабочей частоты. Представлены численные
оценки локализации нагрева в зависимости от области облучения. Также рассмотрены результаты модели-
рования с использованием воксельных моделей.
УСТАНОВКА ДЛЯ ЕЛЕКТРОМАГНІТНОЇ ГІПЕРТЕРМІЇ, ЩО ҐРУНТУЄТЬСЯ
НА ФАЗОВАНОМУ МАСИВІ ВИПРОМІНЮВАЧІВ
А.М. Фадєєв, С.М. Полозов, E.А. Перельштейн, С.М. Іванов
Гіпертермія є багатообіцяючим способом для збільшення ефективності хіміо- і променевої терапії за до-
помогою підвищення температури пухлини. Гіпертермія − додатковий до традиційних метод лікування он-
кологічних захворювань, при якому відбувається підвищення температури пухлини до 43...44°C. Фазований
масив випромінювачів для електромагнітної гіпертермії був запропонований раніше. Нагрівання забезпечу-
ється поглинанням електромагнітної енергії, сфокусованої в пухлині при зміні фаз і амплітуд хвиль, що ге-
неруються кожним з випромінювачів. Частота випромінювання відіграє значну роль у формуванні розподілу
питомого коефіцієнта поглинання (ПКП). Розглядається фазований масив випромінювачів. Обговорюються
принципи вибору робочої частоти. Представлено чисельні оцінки локалізації нагрівання залежно від області
опромінення. Також розглянуто результати моделювання з використанням воксельних моделей.
http://niremf.ifac.cnr.it/tissprop/
Introduction
1. the phased array
references
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| id | nasplib_isofts_kiev_ua-123456789-112091 |
| institution | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| issn | 1562-6016 |
| language | English |
| last_indexed | 2025-12-07T17:55:00Z |
| publishDate | 2013 |
| publisher | Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| record_format | dspace |
| spelling | Fadeev, A.M. Polozov, S.M. Perelstein, E.A. Ivanov, S.M. 2017-01-17T15:32:45Z 2017-01-17T15:32:45Z 2013 Facility for the electromagnetic hyperthermia based on the phased array / A.M. Fadeev, S.M. Polozov, E.A. Perelstein, S.M. Ivanov // Вопросы атомной науки и техники. — 2013. — № 6. — С. 220-224. — Бібліогр.: 8 назв. — англ. 1562-6016 PACS: 87.54.B https://nasplib.isofts.kiev.ua/handle/123456789/112091 Hyperthermia is a promising approach to improve of the chemo- and the radiotherapy efficiency by means of increasing tumor’s temperature. Hyperthermia is an additional method to conventional treatments of oncological disease wherein tumor temperature is increased up to 40…43°C. The phased array of applicators for electromagnetic hyperthermia was suggested earlier. The heating is provided by absorption of electromagnetic energy focused in tumor by varying phases and amplitudes of each of dipoles. Operating frequency plays the significant role in specific absorption rate (SAR) distribution forming. The phased array antenna is under consideration. Principles of choosing of operating frequency are discussed. Numerical estimates of heat localization depending on the radiation area are presented. Also simulation results with voxel model are considered. Гіпертермія є багатообіцяючим способом для збільшення ефективності хіміо- і променевої терапії за допомогою підвищення температури пухлини. Гіпертермія − додатковий до традиційних метод лікування онкологічних захворювань, при якому відбувається підвищення температури пухлини до 43...44°C. Фазований масив випромінювачів для електромагнітної гіпертермії був запропонований раніше. Нагрівання забезпечується поглинанням електромагнітної енергії, сфокусованої в пухлині при зміні фаз і амплітуд хвиль, що генеруються кожним з випромінювачів. Частота випромінювання відіграє значну роль у формуванні розподілу питомого коефіцієнта поглинання (ПКП). Розглядається фазований масив випромінювачів. Обговорюються принципи вибору робочої частоти. Представлено чисельні оцінки локалізації нагрівання залежно від області опромінення. Також розглянуто результати моделювання з використанням воксельних моделей. Гипертермия является многообещающим способом для увеличения эффективности химио- и лучевой терапии посредством повышения температуры опухоли. Гипертермия – дополнительный к традиционным метод лечения онкологических заболеваний, при котором происходит повышение температуры опухоли до 43…44°C. Фазированный массив излучателей для электромагнитной гипертермии был предложен ранее. Нагрев обеспечивается поглощением электромагнитной энергии, сфокусированной в опухоли при изменении фаз и амплитуд волн, генерируемых каждым из излучателей. Частота излучения играет значительную роль в формировании распределения удельного коэффициента поглощения (УКП). Рассматривается фазированный массив излучателей. Обсуждаются принципы выбора рабочей частоты. Представлены численные оценки локализации нагрева в зависимости от области облучения. Также рассмотрены результаты моделирования с использованием воксельных моделей. en Національний науковий центр «Харківський фізико-технічний інститут» НАН України Вопросы атомной науки и техники Применение ускоренных пучков. Детекторы и детектирование ядерных излучений Facility for the electromagnetic hyperthermia based on the phased array Установка для електромагнітної гіпертермії, що ґрунтується на фазованому масиві випромінювачів Установка для электромагнитной гипертермии, основанная на фазированном массиве излучателей Article published earlier |
| spellingShingle | Facility for the electromagnetic hyperthermia based on the phased array Fadeev, A.M. Polozov, S.M. Perelstein, E.A. Ivanov, S.M. Применение ускоренных пучков. Детекторы и детектирование ядерных излучений |
| title | Facility for the electromagnetic hyperthermia based on the phased array |
| title_alt | Установка для електромагнітної гіпертермії, що ґрунтується на фазованому масиві випромінювачів Установка для электромагнитной гипертермии, основанная на фазированном массиве излучателей |
| title_full | Facility for the electromagnetic hyperthermia based on the phased array |
| title_fullStr | Facility for the electromagnetic hyperthermia based on the phased array |
| title_full_unstemmed | Facility for the electromagnetic hyperthermia based on the phased array |
| title_short | Facility for the electromagnetic hyperthermia based on the phased array |
| title_sort | facility for the electromagnetic hyperthermia based on the phased array |
| topic | Применение ускоренных пучков. Детекторы и детектирование ядерных излучений |
| topic_facet | Применение ускоренных пучков. Детекторы и детектирование ядерных излучений |
| url | https://nasplib.isofts.kiev.ua/handle/123456789/112091 |
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