Publications by authors named "Janusz Winiecki"

In this study, we propose novel three-layer composite scintillators designed for the simultaneous detection of different ionizing radiation components. These scintillators are based on epitaxial structures of LuAG and YAG garnets, doped with Ce and Sc ions. Samples of these composite scintillators, containing YAG:Ce and LuAG:Ce single crystalline films with different thicknesses and LuAG:Sc single crystal substrates, were grown using the liquid phase epitaxy method from melt solutions based on PbO-BO fluxes.

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In this study, Ce-doped LuAlO garnet (LuAG) crystal detectors, with a density of ρ = 6 g/cm and an effective atomic number Z = 62, are proposed as promising materials for radiotherapy applications. This type of detector demonstrates excellent uniformity of structural and optical properties, high thermoluminescence (TL) light yield, optimal position of main TL glow peaks at temperatures around 245-295 °C, and high radiation stability. The set of TL detectors made from LuAG:Ce single crystal was used to evaluate the uniformity of dose and energy spectra of X-ray radiation from a clinical accelerator with 6 MV and 15 MV beams at the Department of Medical Physics, Oncology Center in Bydgoszcz, Poland, and γ-rays from a Co source at the National Institute of Oncology in Warsaw.

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Purpose: The purpose of this study was to evaluate three techniques of irradiation of left-sided breast cancer patients, three-dimensional conformal radiotherapy (3D-CRT), hybrid Intensity-Modulated Radiotherapy (h-IMRT), and hybrid Volumetric-Modulated Arc Therapy (h-VMAT, h-ARC), in terms of dose distribution in the planning target volume (PTV) and organs at risk (OARs). The second aim was to estimate the projected relative risk of radiation-induced secondary cancers for hybrid techniques.

Materials And Methods: Three treatment plans were prepared in 3D-CRT, h-IMRT, and h-VMAT techniques for each of the 40 patients, who underwent CT simulation in deep inspiration breath-hold (DIBH).

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The papers published in the first and second Special Issues of "Materials for Luminescent Detectors and Transformers of Ionizing Radiation" were selected from the manuscripts related to the respective presentations at the 11th International Conference on Luminescent Detectors and Transformers of Ionizing Radiation (LUMDETR 2021), which was organized by the Institute of Physics of Kazimierz Wielki University of Bydgoszcz and Oncology Center prof [...

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Thermostimulated luminescence (TSL) dosimetry is a versatile tool for the assessment of dose from ionizing radiation. In this work, the Ce doped YAlO garnet (YAG:Ce) with a density ρ = 4.56 g/cm and effective atomic number Z = 35 emerged as a prospective TSL material in radiotherapy applications due to its excellent radiation stability, uniformity of structural and optical properties, high yield of TSL, and good position of main glow peak around 290-300 °C.

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Purpose: The purpose of this study was to compare two techniques of irradiation of left-sided breast cancer patients who underwent breast-conserving surgery, three-dimensional conformal radiotherapy technique (3D-CRT) and volumetric modulated arc therapy (VMAT), in terms of dose distribution in the planning target volume (PTV) and organs at risk (OARs). The second aim of the study was estimation of the projected risk of radiation-induced secondary cancer for both radiotherapy techniques.

Materials And Methods: For 25 patients who underwent CT simulation in deep inspiration breath-hold (DIBH), three treatment plans were generated: one using a three-dimensional conformal radiotherapy technique and two using volumetric modulated arc therapy.

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Background/aim: Comparison of transplant outcomes in long-term follow-up of children after total body irradiation (TBI)- or chemotherapy-based conditioning allogeneic hematopoietic cell transplantation (allo-HCT).

Patients And Methods: Patients undergoing allo-HCT for Acute lymphoblastic leukemia (ALL) conditioned either with TBI (n=55) or chemotherapy (n=84) were compared. The following transplant outcomes were analyzed: overall survival (OS), event-free survival (EFS), relapse incidence (RI), and graft-versus-host-disease (GVHD)-free-relapse-free survival (GRFS).

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Purpose: The purpose of this study was to compare the absorbed dose distributions within the heart and lad in patients with left-sided breast cancer who underwent radiotherapy using 3D-CRT, IMRT and VMAT techniques.

Methods: The treatment plans of 11 patients with left-sided breast cancer were analyzed. All of the patients were irradiated in our facility with DIBH 3D-CRT.

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Point defects, impurities, and defect-impurity complexes in diamond microcrystals were studied with the cathodoluminescence (CL) spectroscopy in the scanning electron microscope, photoluminescence (PL), and Raman spectroscopy (RS). Such defects can influence the directions that microcrystals are grown. Micro-diamonds were obtained by a hot-filament chemical vapor deposition (HF CVD) technique from the methane-hydrogen gas mixture.

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Purpose: To evaluate usefulness of hyaluronic acid (HA) hydrogel as a tumour bed marker in breast conserving therapy (BCT). To analyze inter- (Inter-OV) and intraobserver (Intra-OV) variability of contouring boost target volume (CTV) in external beam radiotherapy (EBRT).

Materials And Methods: Thirty-two patients in the HA group and 30 patients in the control group with an early stage breast cancer were included in the study.

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Purpose: To evaluate and compare plasma osteopontin (OPN, a candidate prostate cancer biomarker) levels in prostate cancer patients receiving radiotherapy or combined radiotherapy or hormone therapy.

Methods: OPN levels were determined by ELISA in 40 prostate cancer patients eligible for radiotherapy (n=18 radiotherapy alone, n=22 combined radiotherapy and hormone therapy) before the start of irradiation, during treatment, and one month after its completion.

Results: OPN levels were significantly higher (p=0.

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Purpose: The purpose of this study was to develop a method for dose distribution visualization in the case of Electron Beam Intraoperative Radiotherapy based on the images obtained in the operating room. This cannot be relied on CT images obtained before surgery due to significant tissue deformation.

Methods: The ultrasound scanning is the only method to obtain 3-dimensional (3D) reconstruction of a patient's tissue under operating room conditions.

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Background: During a proper execution of dMLC plans, there occurs an undesired but frequent effect of the dose locally accumulated by tissue being significantly different than expected. The conventional dosimetric QA procedures give only a partial picture of the quality of IMRT treatment, because their solely quantitative outcomes usually correspond more to the total area of the detector than the actually irradiated volume.

Aim: The aim of this investigation was to develop a procedure of dynamic plans verification which would be able to visualize the potential anomalies of dose distribution and specify which tissue they exactly refer to.

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