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1

Wearable Textile Antenna for Glucose Level Monitoring

Ghodake Asha, Hogade Balaji

International Journal of Electronics and Telecommunications

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2023

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Vol. 69, No. 2

219--224

EN

Wearable antennas are becoming increasingly popular as a result of their wide range of applications, including communication, health parameter monitoring, and so on. If the wearable antenna is built of textile material, it is highly comfortable to wear and has numerous benefits, such as light weight, compact size, and low cost. A 1.3 GHz microstrip antenna made from jeans substrate is presented in this work. For antenna conducting patch and ground plane copper material is used. The electromagnetic properties of the jean’s substrate are dielectric constant ℇr = 1.7 and loss tangent tan δ = 0.01. In this work the main purpose or application of this antenna is to observe three levels of glucose, i.e., hypoglycemia, hyperglycemia, and normal glucose. The antenna is placed over the arm in the first scenario, while the finger is placed over the antenna patch in the second case. When the glucose concentration in the blood varies, the blood properties change, and the antenna frequency shifts as a result. [That] This frequency shift is used to find out the three glucose levels. The advantage of jeans substrate is that you can wear this antenna very easily over your arm. The antenna is designed using HFSS software and tested using an arm phantom and a finger phantom designed in HFSS.

2

Development of a standard phantom for diffusion-weighted magnetic resonance imaging quality control studies: A review

Manson Eric Naab, Mumuni Abdul Nashirudeen, Shirazu Issahaku, Hasford Francis, Inkoom Stephen, Sosu Edem, Aikins Mark Pokoo, Mohammed Gedel Ahmed

Polish Journal of Medical Physics and Engineering

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2022

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Vol. 28, Iss. 4

169--179

EN

Various materials and compounds have been used in the design of diffusion-weighted magnetic resonance imaging (DWMRI) phantoms to mimic biological tissue properties, including diffusion. This review thus provides an overview of the preparations of the various DW-MRI phantoms available in relation to the limitations and strengths of materials/solutions used to fill them. The narrative review conducted from relevant databases shows that synthesizing all relevant compounds from individual liquids, gels, and solutions based on their identified strengths could contribute to the development of a novel multifunctional DW-MRI phantom. The proposed multifunctional material at varied concentrations, when filled into a multi-compartment Perspex container of cylindrical or spherical geometry, could serve as a standard DW-MRI phantom. The standard multifunctional phantom could potentially provide DW-MRI quality control test parameters in one study session.

3

Quantitative analysis of Gamma Knife stereotactic radiosurgery for uveal melanoma

Bisht Raj Kishor, Natanasabapathi Gopishankar, Kale Shashank Sharad

Polish Journal of Medical Physics and Engineering

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2020

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Vol. 26, Iss. 2

111--117

EN

The purpose of the study was to analyze single fraction Gamma Knife stereotactic radiosurgery (SRS) for uveal melanoma (UM). In the treatment of UMs, the dose distribution exhibited by an irregular eye surface has more calculation uncertainty. A tissue-equivalent bolus was placed on the left eye surface of a human head-shaped phantom. It was assumed that the treated eye is fixed using retrobulbar anesthesia and suture on extraocular muscles for phantom study. Leksell stereotactic frame was fixed around phantom’s head and the stereotactic computed tomography (CT) was performed. Two sets of scans were acquired (a) without bolus and (b) with a bolus of 1.0 cm thickness. These scans were transferred into a treatment planning system (TPS). The skull contouring was performed using stereotactic CT images. The target, visual pathways, and eye lens were delineated in stereotactic CT space created on TPS. A clinical relevant plan was designed on the CT study set “a” to deliver a radiation dose of 30Gy at tumor margin. The plan superimposed over CT study set “b” and compiled for convincing treatment strategy. The tumor coverage was 95% at 50% prescription isodose line. The conformity index, selectivity and the gradient index were 1.27, 0.80 and 3.28 respectively. The left optic nerve and eye lens received a maximum dose of 11.1 Gy and 11.0 Gy respectively. The treatment plan overlay showed similar planning indices and critical organ doses. The plan comparison showed: an irradiated volume received the radiation dose > 15 Gy varies < 1.0% whereas the volume received < 15 Gy were larger (> 1.0%) in the study set “b”. The distant lateral points from the target volume which describe the phantom’s eyelid showed a radiation dose of 3.2 Gy - 2.5 Gy. The doses to these points were misled and ignored in the CT study set “a”. The eye bolus provides better dosimetric information in the estimation of low dose areas which is commonly misled on TPS in SRS planning for UMs.

4

Quality control test of cone beam computed tomography - constancy tests

Redutko J., Wrona K., Szarek A., Bańczyk Ł.

Journal of Achievements in Materials and Manufacturing Engineering

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2020

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Vol. 102, nr 2

66--75

EN

Purpose: The paper describes tests of CBCT cone beam scanners carried out to ensure projection quality. Design/methodology/approach: During the studies, phantoms were scanned with a leading brand volumetric CT scanner according to the device manufacturer's recommendations. The water phantom and phantom made of PMMA with materials of different radiological densities were used in the performed tests. The image area during the tests was determined as a cylinder with diameter of 80 mm and height of 90 mm. In turn, exposure parameters were selected on the basis of clinically applied protocols of cranial imaging. Within carried out research, tests of noise level were performed, image homogeneity was analysed and Hounsfield units constancy was determined. To this end, 18 quality control tests were analysed, which were performed at intervals of about 30 days. Images obtained during phantom scans were analysed by determining the Hounsfield value of selected areas and their changes over time. Findings: The analysis of all carried out projection quality control tests showed that they met the criteria set by the manufacturer, falling within the predefined value ranges. One of the performed tests presented results approaching the limit of acceptable values. After notifying this case, it was shown that the CT scanner was serviced during that period. The obtained results of the quality control tests of water phantom as well as of the material phantom imaging were maintained at similar levels after the service activities. No changes were observed in the obtained mean values of Hounsfield units, which would indicate a decrease in diagnostic quality of CBCT projections. Research limitations/implications: The results presented in this publication require further analysis. These should be complemented by incl. analyses of spatial resolution and image geometry. Practical implications: Carried out research has shown that cyclical quality control testing by a qualified operator is an essential activity to ensure high diagnostic quality of the device. In addition, this analysis showed that procedures of in-service tests should not be omitted and delayed. Originality/value: Originality in these tests is the possibility to improve the procedures for performing basic quality control tests.

5

Fantomy do testowania systemów obrazowania medycznego w PET na przykładzie fantomu Jaszczaka

Wac-Włodarczyk A., Danilczuk A.

Przegląd Elektrotechniczny

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2018

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R. 94, nr 8

110--114

PL

W artykule opisano metodę diagnostyki radioizotopowej PET. Nakreślono zarys wymogów dotyczących kontroli jakości skanerów do badań PET. Wymieniono i scharakteryzowano podstawowe testy jakości określone w normach NEMA i IEC, przedstawiono budowę i zasadę działania fantomów niezbędnych do ich wykonania. Zbadano przykładową metodę kontroli jakości z wykorzystaniem fantomu Jaszczaka w zakresie jednorodności, rozdzielczości oraz kontrastu.

EN

At the article the nuclear medicine medical imaging method known as a positron emission tomography was described. Outlined requirements for quality control of PET scanners. Basic quality tests NEMA and IEC standards were selected and described. The construction and operation principle of the necessary quality control phantoms were presented. En example of a method of quality control with the use of phantom Jaszczak in terms of uniformity, resolution and contrast were examined.

6

High-resolution computed microtomography for the characterization of a diffusion tensor imaging phantom

Kaczmarek Ł., Wejrzanowski T., Skibiński J., Maksimczuk M., Krzyżak A.

Acta Geophysica

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2017

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Vol. 65, no. 1

259--268

EN

This paper addresses the issue of the quantitative characterization of the structure of the calibration model (phantom) for b-matrix spatial distribution diffusion tensor imaging (BSD-DTI) scanners. The aim of this study was to verify manufacturing assumptions of the structure of materials, since phantoms are used for BSD-DTI calibration directly after manufacturing. Visualization of the phantoms’ structure was achieved through optical microscopy and high-resolution computed microtomography (µCT). Using µCT images, a numerical model of the materials structure was developed for further quantitative analysis. 3D image characterization was performed to determine crucial structural parameters of the phantom: porosity, uniformity and distribution of equivalent diameter of capillary bundles. Additionally calculations of hypothetical flow streamlines were also performed based on the numerical model that was developed. The results obtained in this study can be used in the calibration of DTI-BST measurements. However, it was found that the structure of the phantom exhibits flaws and discrepancies from the assumed geometry which might affect BSD-DTI calibration.

7

Kontrola jakości w spektroskopii 1H MRS

Skorupa A., Sokół M., Wicher M.

Inżynier i Fizyk Medyczny

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2016

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Vol. 5, nr 6

323--328

PL

Spektroskopia rezonansu magnetycznego in vivo (MRS) jest nieinwazyjnym narzędziem pozwalającymbadać procesy zachodząceworganizmach żywych na poziomiemolekularnym. Możliwość ilościowej analizy biochemicznej wybranego obszaru zainteresowania czyni tę technikę cenną, zwłaszcza w zastosowaniu do wspomagania diagnostyki zmian w mózgu. Jeśli jednak MRS ma znaleźć swoje stałe miejsce w praktyce klinicznej, wymaga prostego i wiarygodnego systemu kontroli jakości QC (Quality Control) oraz standaryzacji technik akwizycji widm i wysokiej jakości danych spektroskopowych. Kontrola jakości procedur MRS jest zatem niezbędna zarówno, by upewnić się, że system MR jest optymalnie skalibrowany do badań spektroskopowych, jak i na etapie zbierania danych i ich przetwarzania. W artykule przedstawiono ogólną strategię funkcjonowania systemu QC na obu poziomach, opisano podstawowe testy, wskazano sugerowane kryteria ich akceptacji i podanoogólne zasady analizy widm MR.

EN

Localized Magnetic Resonance Spectroscopy (MRS) is a nuclear magnetic resonance-based technique that allows in vivo non-invasive measurements of biomolecules. The feasibility of acquiring quantitative biochemical information from a certain region of interest makes this technique especially valuable in assisting the diagnosis of brain lesions. However, if MRS is to be used in clinical practice, it requires a simple and reliable system of quality control (QC), standardization of acquisition of spectra and collecting high quality spectroscopic data. The MRS quality control system is, thus, necessary both, to ensure that MR system is optimally calibrated for spectroscopic studies, as well as it is required at the time of data acquisition and data post-processing. This paper outlines a recommended general QC testing strategy, overviews some basic tests, provides their suggested acceptance criteria and describes the general aspects of post-processing of MR spectra.

8

Left ventricle phantom and experimental setup for MRI and echocardiography – Preliminary results of data acquisitions

Cygan S., Werys K., Błaszczyk Ł., Kubik T., Kałużyński K.

Biocybernetics and Biomedical Engineering

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2014

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Vol. 34, no. 1

19--24

EN

Methods for imaging myocardial strains are a subject of intense research. Many methods are being proposed by scientists from numerous laboratories. Those methods are designated for ultrasonic imaging or for magnetic resonance tomography. Attempts to quantitatively compare results obtained from those modalities are scarce. In this work a left ventricle phantom and an experimental setup are described, that enable subsequent acquisition of ultrasonic and MRI data with a well defined phantom geometry and deformation pattern and thus enabling quantitative comparison of strain estimation results. Tagged MRI and ultrasonic RF data appropriate for strain estimation techniques have been registered and presented.

9

Zastosowanie mikroprocesorowych układów pomiaru kąta obrotu w budowie fantomu do generowania programów roboczych robotów FANUC ARCMate 100iB

Reclik D., Kaczmarczyk P.

Pomiary Automatyka Robotyka

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2012

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R. 16, nr 2

206-213

PL

W pracy omówiono projekt i realizację mikroprocesorowego układu do pomiaru absolutnych wartości położeń kątowych 6 przetworników rezystancyjnych. Przeznaczeniem projektowanego układu pomiarowego była instalacja w modelu robota FANUC ARCMate100iB wykonanego metodami szybkiego prototypowania. Założeniem projektu było utworzenie modelu dydaktycznego prezentującego wykorzystywaną we wczesnych latach 90. w USA, technikę programowania robotów przemysłowych metodą "teaching-by-showing", której głównym założeniem było wykorzystanie fantomu do wyznaczania pożądanych położeń łańcucha kinematycznego programowanego robota poprzez wskazywanie położeń za pomocą poruszanego ręcznie modelu robota. Aby możliwe było programowanie robotów przy wykorzystaniu mechatronicznego układu zadajnika trajektorii typu fantom konieczne było spełnienie dwóch podstawowych kryteriów wpływających na dokładność wyznaczanych położeń. Pierwszym założeniem była pełna skalowalność modelu, czyli zachowanie proporcji wymiarowych względem fizycznego manipulatora, w taki sposób, aby możliwe było precyzyjne odzwierciedlenie położenia fantomu w rzeczywistym systemie zrobotyzowanym. Drugim warunkiem pozwalającym na wykorzystanie tego typu zadajników trajektorii w procesie programowania metodami nauczania było zastosowanie odpowiedniego układu pomiarowego do pomiaru położenia kątowego kolejnych ogniw łańcucha kinematycznego fantomu. Jak pokazały przeprowadzone badania, dokładność wyznaczania położeń pośrednich trajektorii programowanego robota zależy w większym stopniu od dokładności metod pomiaru kątów obrotu ramion fantomu niż od precyzyjnego zachowania skali samego układu mechanicznego. Przeprowadzone obliczenia wykazały, że dokładności pomiaru kątów obrotu muszą być o jeden rząd większe niż dokładności wykonania części mechanicznej (odległości punktów mocowania przegubów obrotowych ramion modelu robota), dlatego też postanowiono opublikować uzyskane wyniki, a także wnioski wyciągnięte z przeprowadzonych eksperymentów z udziałem wykonanego systemu przy programowaniu rzeczywistych robotów ARCMate 100iB, przy uwzględnieniu systemu pomiarowego oraz przyjętej metody pomiarów absolutnych wartości kątów obrotu ramion fantomu.

EN

The main goal of this work is to present the project and method for realization of microprocessor measurement system for measuring total angle position of rotary potentiometer. The presented solution is installed in FANUC ARCMate 100iB manufacturing robot, which is created by usage of fast prototyping methods. The main assumption of the presented work was to use phantom for determining the suitable kinematic chain positions of the robot. It is realized by pointing the position by the usage of manually moved robot model. To make robot programming possible, in this case, it was needed to fulfill the two main assumptions. First of all, the full model scaling was necessary, which means to keep the corresponding dimension proportion regarded to normal manufacturing robot. Second of all, we had to applied the suitable measuring system for measuring the angle position of following kinematic chain elements of phantom. The results show that, the precision in determining the indirect positions of robot trajectory mainly depend on accuracy of methods for measuring the angle rotation of phantom arms. Moreover, the calculations carried out that, the precision of angle rotation measurements must be higher than the quality of real mechanical model.

10

Antropomorficzny fantom dla obrazowania MRI całego ciała

Sieńczewski M., Malczyk J., Tadeusiak M., Aksamit D., Płachta J.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2012

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Vol. 18, nr 2

155-156

PL

Celem pracy było zbudowanie antropomorficznego fantomu rezonansu magnetycznego (MRI), do wspomagania oceny poprawności obrazowania całego ciała. Zespół studentów z Koła Naukowego Techniki w Medycynie oraz Koła Naukowego Fizyków przeprowadził badania materiałów, a następnie skonstruował prototyp fantomu.

EN

The purpose of examination was to create anthropomorphic magnetic resonanse phantom, which supports evaluation of correction for whole-body imaging procedure. Members of "Scientific Students’ Circle Techniques in Medicine" and "Physic's Scientific Students' Circle" examined the materials and constructed the prototype of the phantom.

11

A hand phantom for radiological measurements

Majowska B., Tuszyński M.

Nukleonika

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2005

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Vol. 50, nr 4

167-172

EN

The paper presents the construction of a hand phantom and its usefulness for radiological measurements. Situations when the hand is exposed to ionizing radiation stimulated the invention of this phantom. An extremity dosimeter was placed on the middle finger of the phantom. All measured doses are relative. The doses were compared with the dose from the extremity dosimeter. The aim of this paper was not to show values of the measured doses in legal units but the authors wanted to show the difference between the dose received by the extremity dosimeter and the doses measured on the inside of the hand phantom. High-sensitive LiF:Mg,Cu,P thermoluminescence detectors were used for the measurements because of their small size and close tissue equivalence. The hand phantom makes it possible to acquire the dose distribution on the inside of the hand. The authors suggested the calculation of the coefficients: the average hand phantom coefficient CHPhAV and the maximum hand coefficient CHPhmax from phantom measurements. The extremity dosimeter dose estimates according to the recommended coefficients allowed to obtain more reliable values.

12

Study of displacement estimation methods for elastographic applications

Kałużyński K., Leśniak B., Cygan S.

Elektronika : konstrukcje, technologie, zastosowania

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2004

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Vol. 45, nr 8-9

135-138

EN

Two methods of displacement estimation - based on the 1D maximum crosscorrelation coefficient and on the minimum of the sum of absolute differences (SAD) were tested on the RF and baseband envelope data, obtained from a homogenous tissue phantom, submitted to a quasistatic deformation, uniform in the analysed area of size approx. 3 mm x 22 mm. The maximum strain ranged from 2.4% to 7.5%. The data processing consisted in choosing a 1D correlation/SAD kernel of length from 0.4 mm to approx. 1.5 mm, and comparing it within a search kernel ranging from approx. 0.7 mm to 1.8 mm. The displacement images were submitted to a 1D median filtering and to smoothing. The processing was carried out in the MATLAB environment. Use of the RF data appeared fundamental to obtain low variance displacement estimates. The best results were obtained using the SAD method.

PL

Badaniom poddano metodę estymacji przemieszczeń opartą na poszukiwaniu maksimum współczynnika korelacji 1D oraz metodę wykorzystującą minimum sumy różnic bezwzględnych SAD. Analizowano dane RF oraz dane w paśmie podstawowym, pochodzące z jednorodnego fantomu tkankowego poddanego jednorodnemu quasistatycznemu odkształceniu, dla obszaru o wymiarach ok. 3 mm x 22 mm. Maksymalne wartości odkształceń wynosiły 2.4% - 7.5%. Przetwarzanie polegało na porównywaniu jądra o długości od 0.4 mm do 1.5 mm z obszarem poszukiwań o wymiarach od 0.7 mm do 1.8 mm. Obrazy przemieszczeń poddano filtracji medianowej i wygładzaniu. Przetwarzanie przeprowadzono w środowisku MATLAB. Estymację przemieszczeń o najniższej wariancji zapewnia wykorzystanie danych RF oraz metody SAD.