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1

Electrosurgical resection of colorectal polyps - mathematical modelling of processes during medical treatment

Siedlecki Jarosław

Journal of Applied Mathematics and Computational Mechanics

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2023

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Vol. 22, nr 3

43--56

EN

The colonoscopic electrosurgical polypectomy is a very popular surgical procedure in which the colon polyps are removed. In this work, the mathematical description of the electrical and thermal processes proceeding during this procedure has been proposed. The mathematical model contains the specification of the considered domain’s geometry, the system of the partial differential equations that governs heat transfer in the considered particular sub-domains (i.e. polyp, colon and electrode) with the adequate initial-boundary conditions, the system of the differential equations for determination of the electrical potential distribution in the tissue sub-domains, and the definition of the Arrhenius tissue damage integral. Next, the example results of numerical simulations for the proper and incorrect positions of the polyp in the colon are presented. The conclusions are also provided. The proposed research can be helpful for the surgeons to choose the optimal set parameters of the electric current during the endoscopy procedure.

2

In vitro cytotoxicity of biodegradable Zn-Mg surgical wires in tumor and healthy cells

Milenin Andrij, Łukowicz Krzysztof, Truchan Karolina, Osyczka Anna Maria

Acta of Bioengineering and Biomechanics

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2021

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Vol. 23, no. 4

85--93

EN

In this work, we examined the in vitro cytotoxicity of new biodegradable surgical wires. The wires made of zinc with the addition of a small amount of magnesium (pure zinc, ZnMg 0.0026, ZnMg 0.0068, and ZnMg 0.08) have been investigated. The wires were produced using a technology based on extrusion and subsequent drawing. The resulting wires with a diameter of 0.8–1.0 mm are designed to be used in surgical operations related to bone joints. For cytotoxicity studies, we have selected human dental pulp stem cells (hDPSC) as the cell population representing normal osteoprogenitor cells. Considering that, after bone surgeries, the chance of osteosarcoma increases, we have compared the results obtained in hDPSC to those obtained with Saos-2 human osteosarcoma cell line. Cultured cells were exposed to the extracts obtained from the materials incubated in culture medium for 24 h with and without preincubation. Extracts of different ratios were examined. The results showed that the extracts obtained from wires made of ZnMg 0.0026 alloy exhibit high toxicity to Saos-2 osteosarcoma cells and low toxicity to hDPSC cells. This was in contrast to all reference materials, i.e., commercial surgical sutures made of steel and polymers, that did not display cytotoxicity toward osteosarcoma cells. Thus, the detected phenomenon for the ZnMg 0.0026 alloy can become the basis for creating biodegradable Zn-Mg surgical wires with antitumor activity.

3

Antiradical properties of chemo drug, carboplatin, in cooperation with ZnO nanoparticles under UV irradiation in putative model of cancer cells

Pairoj Suttirak, Damrongsak Pattareeya, Damrongsak Badin, Jinawath Natini, Kaewkhaw Rossukon, Leelawattananon Tanaporn, Ruttanasirawit Chinnapat, Locharoenrat Kitsakorn

Biocybernetics and Biomedical Engineering

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2019

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Vol. 39, no. 3

893--901

EN

The main objective of this study was to assess the antiradical properties of zinc oxide (ZnO) nanoparticles upon exposure to ultraviolet radiation with carboplatin, an anti-proliferative drug used in the treatment of retinoblastoma. For the purpose of this study, the decomposition of 2,2(diphenyl-1-picryhydrazyl) radical (DPPH*) was used to assess the free radical capacity of antioxidants and was followed by MTT measurements. To test the antiradical capacity, the effective concentration, antiradical power, stoichiometry, and number of reduced DPPH* were investigated. DPPH* has a peak absorbance at a wavelength of 515 nm, which disappears upon the introduction of the antiradical agents. Four agents were reacted with DPPH* and represented the possible reaction kinetic categories. ZnO nanoparticles and carboplatin-loaded ZnO nanoparticles reacted more strongly with DPPH* and approached a saturation state at 420 min. The remaining two antiradical agents, ZnO nanoparticles under UV radiation and carboplatin-loaded ZnO nanoparticles under UV radiation, reacted a bit slower with DPPH* and approached a steady state at 1440 min. Among the different four antiradical agents, carboplatin-loaded ZnO nanoparticles under UV light had the highest antiradical response with the lowest effective concentration value to the reduced DPPH* molecules. ZnO nanoparticles alone were found to be poor antiradical agent. Possible mechanisms were attributed to the number of hydroxyl groups available to decrease the number of DPPH*.

4

Kontrola systemu planowania leczenia w brachyterapii

Wittych J., Sobiech M.

Inżynier i Fizyk Medyczny

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2015

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Vol. 4, nr 4

225--228

PL

Dla każdego etapu radioterapii istnieje szereg regulacji prawnych, które mają na celu głównie poprawę jakości i bezpieczeństwa realizacji całego procesu. Ze względu na konieczność zapewnienia bezwzględnej poprawności i powtarzalności obliczeń systemy planowania leczenia stosowane w radioterapii powinny być objęty kontrolą jakości. Użycie nieprawidłowowprowadzonych danych skutkuje błędami w obliczeniach i napromienianiu pacjenta. Właściwa kontrola powinna zagwarantować możliwość wykonania optymalnego planu leczenia z wykluczeniem błędów wynikających z nieprawidłowo zdefiniowanych danych w TPS. Opublikowano kilka raportów dedykowanych zapewnieniu jakości w radioterapii, w tym również poświęconych systemom planowania leczenia [1-9]. W pracy przedstawiono podstawowe wymogi kontroli systemu planowania leczenia w brachyterapii oparte głównie na zaleceniach Bookletu No. 8 European Society for Radiotherapy and Oncology [9].

EN

There are a lot of regulations in radiotherapy dedicated to quality assurance and safety of this treatment method process. It is also recommended to control used treatment planning systems. It is necessary to be sure that the calculations and reproducibility are correct. Using incorrect data and calculations cause the mistakes in patient irradiation. The reliable quality control ought to guarantee the possibility of calculated optimal and correct treatment plan. There were published some reports for quality control (QC) in radiotherapy especially for quality control of treatment planning systems (TPS) [1-9]. The main requirements for QC of TPS used in brachytherapy, based on recommendations of Booklet No. 8 European Society for Radiotherapy and Oncology [9], were put forward in this paper.

5

Śródoperacyjna metoda obrazowania w podczerwieni ukrwienia tkanek prawidłowych i patologicznych mózgu

Kaczmarska K., Czernicki Z, Zębala M, Kastek M., Piątkowski T., Polakowski H.

Przegląd Elektrotechniczny

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2014

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R. 90, nr 9

38-41

PL

Śródoperacyjna identyfikacja tkanek mózgu objętych procesem chorobowym, precyzyjne dotarcie do nich oraz radykalne ich usunięcie stanowi istotę każdego zabiegu neurochirurgicznego. Celem podjętych badań jest ocena przydatności kamery termowizyjnej do identyfikacji i wyznaczania lokalizacji guzów mózgu oraz opracowanie metodologii obrazowania śródoperacyjnego umożliwiającego analizę zmian temperatury powierzchni kory mózgowej. Analizę termiczną przeprowadzono u sześciu pacjentów z wykrytymi w badaniach obrazowych nowotworami ośrodkowego układu nerwowego. Wyniki pomiarów przeprowadzonych śródoperacyjnie potwierdzają możliwość wykorzystania kamery termowizyjnej do nieinwazyjnej rejestracji temperatury powierzchni kory mózgowej oraz wskazują, że temperatura powierzchni guzów różni się od temperatury powierzchni tkanek nieobjętych zmianą chorobową.

EN

Intraoperative identification of brain tissues affected by the disease, precise access to them and radical removal of them are essence of neurosurgery. The main goal of this work is evaluate the usefulness of intraoperative thermal imaging to determine the location and borders of brain tumors. Moreover, it is important to develop a methodology for intraoperative imaging that allows analysis of the temperature changes of cerebral cortex surface. Preliminary clinical trials were carried out on six patients with tumors of central nervous system diagnosed with magnetic resonance imaging or computed tomography. The results of intraoperative measurements confirm the possibility of using infrared camera for non-invasive record of the temperature distribution of the cerebral cortex surface. The results showed significant differences in temperature of healthy tissues of brain and temperature of tumors.

6

Mathematical modeling of fluid flow in brain tumor

Riahi D. N., Roy R.

Journal of Theoretical and Applied Mechanics

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2014

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Vol. 52 nr 1

271--279

EN

We consider the problem of fluid flow in a brain tumor. We develop a mathematical model for the one-dimensional fluid flow in a spherical tumor where the spatial variations of the interstitial velocity, interstitial pressure and the drug concentration within the tumor are only with respect to the radial distance from the center of the tumor. The interstitial ve- locity in the radial direction and the interstitial pressure are determined analytically, while the radial variations of two investigated drug concentrations were determined numerically. We calculated these quantities in the tumor, in a corresponding normal tissue and for the concentrations also in the cavity that can exist after the tumor is removed. We determine, in particular, the way the interstitial pressure and velocity vary, which agrees with the expe- riments, as well as the way one drug concentration changes in the presence or absence of a second drug concentration within the tumor. We find that the amount of drug delivery in the tumor can be enhanced in the presence of another drug in the tumor, while the ratio of the amount of one drug in the tumor to its amount in the normal tissue can be reduced in the presence of the second drug in the tumor and the tissue.

7

Intelligent sensing and monitoring : respiratory motion prediction for tumor following radiotherapy

Ichiji K., Homma N., Sakai M., Bukovsky I., Zhang X., Osanai M., Abe M., Sugita N., Yoshizawa M.

Journal of Artificial Intelligence and Soft Computing Research

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2012

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Vol. 2, No. 4

331--342

EN

This paper presents a medical application of the intelligent sensing and monitoring, a new lung tumor motion prediction method for tumor following radiation therapy. An essential core of the method is accurate estimation of complex fluctuation of time-varying periodical nature of lung tumor motion. Such estimation is achieved by using a novel multiple time-varying seasonal autoregressive (TVSAR) model in which several windows of different time-lengths are used to calculate correlation based fluctuation of periodic nature in the motion. The proposed method provides the prediction as a combination of those based on different window lengths. Multiple regression (MR), multilayer perceptron (MLP) and support vector regression (SVR) are used to combine and the prediction performances are evaluated by using clinical lung tumor motion. The proposed methods with the combined predictions showed high accurate prediction and are superior to the single different predictions. The average errors of MR, MLP, and SVR were 0.8455,0.8507, and 0.7530 mm at 0.5 s ahead, respectively. The results are clinically sufficient and thus clearly demonstrate that the proposed TVSAR with an appropriate combination method is useful for improving the prediction performance.

8

GPU enhanced simulation of angiogenesis

Worecki M., Wcisło R.

Computer Science

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2012

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Vol. 13 (1)

35-48

EN

In the paper we present the use of graphic processor units to accelerate the most time-consuming stages of a simulation of angiogenesis and tumor growth. By the use of advanced CUDA mechanisms such as shared memory, textures and atomic operations, we managed to speed up the CUDA kernels by a factor of 57x. However, in our simulation we used the GPU as a co-processor and data from CPU was copied back and forth in each phase. It decreased the speedup of rewritten stages by 40%. We showed that the performance of the entire simulation can be improved by a factor of 10 up to 20.

9

MRI image analysis in patients with a tumor of the central nervous system : an attempt of developing a management algorithm

Śniegocki M., Nowacka A., Fisz J., Śniegocka A., Buczkowski M.

Zeszyty Naukowe. Telekomunikacja i Elektronika / Uniwersytet Technologiczno-Przyrodniczy w Bydgoszczy

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2011

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z. 15

49-61

EN

Magnetic resonance imaging study is currently the reference method for the detection and diagnosis of the central nervous system tumors. A large number of tumors, especially high-grade, has a higher water content in the cells, which results in prolongation of MRI T1 and T2 what appearance as increased signal intensity in in T2-weighted images and the reduction in T1-weighted images. MRI can be performed with administration of contrast agent, which shortens T1 and increases signal on T1-weighted sequences. This allows to identify areas of increased angiogenesis), which is the exponent of the cancer malignancy degree and its biological activity. Obtained MRI images are analyzed and evaluated by a radiologist and a clinician. Most of the time it is the "by the eye" analysis, which is based on the MRI image evaluation by the generally accepted radiological standards. However, this method is relatively inaccurate. which in turn can bring to the wrong diagnosis of the disease and implementation or even lack of implementation of appropriate treatment. More and more researches are conducted in this area, but developed methods are usually very complicated and difficult to carry out by the "layman" which is the clinician. That is why the attempt is made, to develop a simple and clear algorithm for MRI image analysis in patients with the central nervous system tumors, allowing for quick and objective evaluation of magnetic resonance imaging study.

PL

Badanie metodą rezonansu magnetycznego jest aktualnie metodą referencyjną przy wykrywaniu i diagnozowaniu nowotworów centralnego układu nerwowego. Duża część nowotworów, zwłaszcza o wysokim stopniu złośliwości, charakteryzuje się większą zawartością wody w komórkach, co w badaniu MRI skutkuje wydłużeniem T1 i T2, uwidocznionym jako nasilenie sygnału w obrazach T2-zależnych oraz jego obniżeniem w obrazach T1-zależnych. MRI można przeprowadzić z podaniem środka kontrastowego, co powoduje skrócenie czasu T1 i podniesienie

10

Radiologia interwencyjna w onkologii: możliwości terapeutyczne leczenia nowotworów wątroby – pierwotnych oraz przerzutów do wątroby

Mól M., Ćwikła J., Nowicki M., Zawadzki M., Kordecki K., Walecki J.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2010

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Vol. 16, nr 2

153-156

PL

Od niedawna radiologia interwencyjna znajduje zastosowanie również w onkologii. W artykule przedstawiono kilka relatywnie innowacyjnych technologii i technik stosowanych w terapii nowotworów pierwotnych wątroby oraz pochodzenia przerzutowego. Kliniczne wskazania i przeciwwskazania do stosowania opisywanych metod i zabiegów nie są przedmiotem rozważań autorów pracy.

EN

Interventional radiology has recently found a place in oncology. This article will describe some relatively new techniques and agents used in the treatment of primary and metastatic malignancies of the liver. The article will not describe clinical indications nor the contraindications to the procedures listed as this is beyond the scope of this publication.

11

Nowe techniki ultrasonograficzne w badaniach tarczycy

Słapa R., Jakubowski W.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2010

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Vol. 16, nr 2

147-150

PL

W artykule omówiono nowe techniki ultrasonograficzne znajdujące zastosowanie w rutynowych badaniach tarczycy oraz będące w fazie prób klinicznych. Nowe techniki ultrasonograficzne można podzielić na: polepszające jakość obrazu w prezentacji B (skali szarości), jak obrazowanie harmoniczne i ultrasonografia złożona; przekształcające badanie w przestrzeni, jak rozszerzone pole widzenia i ultrasonografia trójwymiarowa, oraz dostarczające jakościowo nowych informacji w badaniu ultrasonograficznym, jak mapowanie mikrozwapnień i elastografia.

EN

The new ultrasound techniques applied for routine examinations of thyroid gland, as well as introduced in clinical phase of research studies, were discussed. These can be divided into techniques that improve quality of the image in B mode (gray-scale) as harmonic imaging and compound ultrasound, the techniques transforming examination in space as extended field of view and three-dimensional ultrasound, and finally techniques delivering qualitatively new information in on ultrasound examination as mapping of microcalcifications and elastography.

12

R&D of novel medicinal materials for curing cancer: sugar modified Gd-DTPA MRI contrast agents and phospha sugar anti-cancer agents

Yamashita Y., Yamashita M., Fujie M., Suyama K. A. T., Ito S., Reddy V. K., Yamada M., Ogawa K., Ozaki N., Nakamura S., Aoki T., Yu G., Aoshima K., Kato T., Kamikage N., Kiyofuji K., Takehara Y., Sakahara H., Takayanagi H., Oshikawa T., Laurent S., Burtea C., Van der Elst L., Muller R. N.

Journal of Automation Mobile Robotics and Intelligent Systems

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2009

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Vol. 3, No. 4

80-83

EN

Novel Sugar Dendritic Gd-DTPA Complexes for MRI Contrast Agents were prepared and evaluated by in vitro and in vivo methods. The sugar dendritic MRI contrast agents have a good blood vesse pool character, and draw blood vessels and liver cancer remarkably clearer than the clinically using Gd-DTPA. Phospha sugar derivatives or phosphorus heterocyclic derivatives provided by functional groups such as epoxide, bromide, etc., were prepared and evaluated by MTT in vitro method. These phospha sugar derivatives showed excellent activities against leukemia cells as well as solid cancer cells in fashions of (i) higher activity, (ii) wider spectra, (iii) higher selectivity and specificity distingushing healthy and cancer cells, etc., compared with the molecular targeting chemotheraputic anti-cancer agent, Gleevec.

13

Temperature determination in the tissue with a tumor using MRBEM and FEM

Paruch M., Dziewoński M., Kokot G.

Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej

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2005

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Vol. 4, nr 1

195-203

EN

The numerical algorithms based on the boundary element method and finite element method are used for the temperature field computations in the non homogenous domain being the composition of healthy tissue and the tumor region. The three dimensional problem is considered. Thermophysical parameters of sub-domains, in particular the perfusion coefficients, thermal conductivities and the metabolic heat sources are different. From the mathematical point of view the problem is described by the system of two Poisson's equations with temperature-dependent source functions. These equations are supplemented by the adequate boundary conditions. The algorithms discussed allow, among others, to determine the temperature distribution on the surface of the skin. In the final part of the paper the examples of computations are shown.

14

Modelling of thermal processes occuring in the tissue with a tumor with regard to parameter sensitivity analysis

Majchrzak E., Paruch M., Drozdek J.

Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej

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2004

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Vol. 3, nr 1

133--142

EN

The numerical algorithm based on the multiple reciprocity boundary element method is used for the temperature field computations in the non-homogeneous domain of healthy tissue and the tumor region. The thermophysical parameters of tumor, in particular the perfusion rate, the metabolic heat source and the thermal conductivity are essentially bigger than for healthy tissue. From the mathematical point of view the problem is described by the system of two Poisson's equations supplemented by the adequate boundary conditions. The main subject of the paper is the sensitivity analysis of temperature distribution with respect to the thermal parameters of tumor region and healthy tissue. In the final part of the paper the examples of computations are shown.