Physical Background and Technical Realizations of Hyperthermia

Szász, András; Szász, Olivér; Szász, Nóra

doi:10.1007/978-0-387-33441-7_3

Cited by 29 publications

(23 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These solutions mostly work on electromagnetic principles in four main categories: e.g. magnetic, electric, radiative and galvanic [26], Figure 2 Comparison is with the same output power at same frequency in biological materials. The weak interaction is Eddy current and spin-interactions due to the missing ferromagnetic materials, the medium is the energy-loss of the absorbed waves, the strong uses dielectric loss with electric field, while the extra-strong is a compulsory current by galvanic contacts, producing Joule-heat.…”

Section: Methodsmentioning

confidence: 99%

Hyperthermia Dosing and Depth of Effect

Szász¹,

Peter²,

Vancsik³

et al. 2018

OJBIPHY

Self Cite

View full text Add to dashboard Cite

The penetration depth in the electromagnetic heating could be a crucial factor of its application, when the deep heating is the goal. The capacitive coupling is one of the most popular heating techniques in radiofrequency (RF) heating applications. The matching of the target defines the penetration possibilities. The current matched solution has deeper mathematically defined penetration in RF region than the capacitive plane-wave solution. The same power of application request high voltage with relatively low current for plane-wave inducing, while in current matching it has low voltage with high current. The effective depth of the action in the two solutions do not identical, the penetration defined by the intensity of 1/e portion of the incident beam is higher in the current-matched techniques.

show abstract

Section: Methodsmentioning

confidence: 99%

Hyperthermia Dosing and Depth of Effect

Szász¹,

Peter²,

Vancsik³

et al. 2018

OJBIPHY

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is limited to a very small volume by various interstitial methods, including the most popular radiofrequency (RF) ablation techniques. However, most of the hyperthermia practices in oncology are locally or regionally devoted to solving hyperthermia effects in shallow and deep-seated tumours [4]. The problems in these methods are simply connected to the focusing of heat-energy.…”

Section: Introductionmentioning

confidence: 99%

“…Consequently, the treatment has to be identified by temperature, or at least by the specific energy absorption rate (SAR) in the target. The temperature and the energy-deposition must therefore be controlled.Electromagnetic energy delivery could be by four not completely independent categories, depending on the coupling of the fields to the object; it could be radiation, inductive, capacitive or galvanic coupling [3,4]. All of the interactions have variability in their absorption processes [5], in addition to the structural variations.…”

mentioning

confidence: 99%

Nanoheating without Artificial Nanoparticles Part II. Experimental Support of the Nanoheating Concept of the Modulated Electro-Hyperthermia Method, Using U937 Cell Suspension Model

et al. 2015

View full text Add to dashboard Cite

IntroductionLiving tissue is complexly heterogenic. The processes are mostly chemical reactions, where energy absorption-emission is a central point. The energy liberated by metabolic activity appears in the bodytemperature, which is also very heterogenic by its sources, but is averaged by natural heat-conduction and the connected temperature equalisation. Hyperthermia is a thermal process, defined by a temperature-elevation in the target [1]. The mass-or volume-specific energy absorption (defined by the specific absorption rate [SAR]) increases the temperature.In the definition of hyperthermia, temperature is the obligatory parameter, used for dosing by considering the time for which it was effective [2]. Consequently, the treatment has to be identified by temperature, or at least by the specific energy absorption rate (SAR) in the target. The temperature and the energy-deposition must therefore be controlled.Electromagnetic energy delivery could be by four not completely independent categories, depending on the coupling of the fields to the object; it could be radiation, inductive, capacitive or galvanic coupling [3,4]. All of the interactions have variability in their absorption processes [5], in addition to the structural variations. Consequently, the SAR has microscopic medley values in the living target.Temperature is the average energy of the particles involved in the absorption process. This general temperature is composed of the various different microscopic heating areas, which could be equalised by the heat-conduction and convection in their surroundings by various timecharacters. The macroscopic temperature is a gross-average of all of the microscopic temperatures and their spread-processes.There are some very high-temperatures (over the protein denaturation [6] that can be locally concentrated and are relatively short time applications. It is limited to a very small volume by various interstitial methods, including the most popular radiofrequency (RF) ablation techniques. However, most of the hyperthermia practices in oncology are locally or regionally devoted to solving hyperthermia effects in shallow and deep-seated tumours [4]. The problems in these methods are simply connected to the focusing of heat-energy. The energy can be focused by choosing the targeted volume, but due to the non-invasive solutions, the input power is limited by adverse effects, so longer duration is necessary to heat up the target. The longer heating time completely changes the situation; we have to take into account the natural movements of the patient, which heats up the healthy environment, and naturally occurs because of the effective heat-diffusion and heat-conduction in the body. The energy can be focused for longer times to a chosen target volume, but the heat (and the temperature) is not focusable for longer, as it naturally spreads.The consequences of heat spreading can dramatically change the complete hyperthermia process. The homeostatic regulation of the body tries to re-establish the homeostatic equilibrium. C...

show abstract

“…There are numerous technical solutions [1,2] but the results are mostly controversial like the cervix studies (the positive [3] and the opposite effects [4] of hyperthermia were published). The basic problem is the missing control, due to the simple fact of the focusing possibilities.…”

Section: Introductionmentioning

confidence: 99%

Oncothermia Application for Various Malignant Diseases

Lee¹

2013

Conference Papers in Medicine

View full text Add to dashboard Cite

Oncothermia was introduced to our hospital in 2010. Our objective is to report results of 277 patients treated by oncothermia during 20 months. We present some characteristic cases and statistical study of the overall results. We concluded by stating the feasibility of oncothermia to treat high variety of malignant diseases also in their very advanced (T4N3M1) stages. BackgroundHyperthermia is a long-time used treatment in oncology, having debates about its applicability and working mechanisms. There are numerous technical solutions [1,2] but the results are mostly controversial like the cervix studies (the positive [3] and the opposite effects [4] of hyperthermia were published). The basic problem is the missing control, due to the simple fact of the focusing possibilities. The sophisticated technologies are concentrating the localized and focused energy on the target; however the temperature is distributed from any sharply focused volume, naturally trying to be equalized in its neighborhood. The smearing of the temperature is accelerated by the physiologic feedback to cool down the specially heated volume by the extra blood flow in the heated part of the body [5,6]. The extra blood flow naturally supports the tumor by nutrients (mainly glucose) and increases the risk of dissemination. The focusing and heating mechanisms are certainly different in various kinds of technical solutions, which reflects the problem of the standardization; no reference point exists [7]. MethodAvoiding the controversies, oncothermia was used in our study. Oncothermia has realized the root of the problem: impossibility to localize the temperature in the desired volume. The solution was the nanoheating technology.Oncothermia selects and heats up very locally (in nanoscopic range) the membrane of the malignant tumors, [8]. This effect excites important pathologic pathways to promote apoptosis [9] and overcome the main problem of the technical challenge by large energy intake but on a very well-localized place. It needs 60 min to reach the general temperature equilibrium, which is the time of the active oncothermia session. The oncothermia in this line is working permanently by thermal nonequilibrium conditions.We collected all patients ( = 277) who had at least one oncothermia treatment in time interval November 2010-July 2013 (20 months). The patient group had = 125 males and = 152 females. Average age was 53 y (7-84 y). The various diseases and the number of patients involved in the study were heterogeneous (see Figure 1) aiming to check the efficacy on the wide range of diseases and stages.Major target areas were lung 53, stomach 33, breast 30, and colon 25. We assume the reason why lung cancer was the highest number. It is not only because lung cancer is the most common cancer in Republic of Korea but also other area's cancers easily metastasize to lung.The treatment had step-up heating protocol (60 W → 150 W), using 20 cm and 30 cm diameter electrodes. The stepup grades were fit by personalization, with careful control of the actua...

show abstract

Physical Background and Technical Realizations of Hyperthermia

Cited by 29 publications

References 61 publications

Hyperthermia Dosing and Depth of Effect

Hyperthermia Dosing and Depth of Effect

Nanoheating without Artificial Nanoparticles Part II. Experimental Support of the Nanoheating Concept of the Modulated Electro-Hyperthermia Method, Using U937 Cell Suspension Model

Oncothermia Application for Various Malignant Diseases

Contact Info

Product

Resources

About