Purpose: This study was performed to evaluate the role of in vivo dosimetry with semiconductor detectors in gynaecological medium dose rate brachytherapy, and to compare the actual doses delivered to organs at risk (as measured using in vivo dosimetry) with those calculated during treatment planning.
Materials And Methods: Doses to the rectum and bladder were measured in a group of patients with cervical carcinoma using semiconductor detectors and compared to the doses calculated using a treatment planning system. 36 applications of brachytherapy at dose rates of 1.8-2.3 Gy/h were performed in the patients.
Results: The mean differences between the measured and calculated doses were 3 % for the rectum and 11 % for the bladder.
Conclusions: The main reason for the differences between the measured and calculated doses was patient movement. To reduce the risk of large errors in the dose delivered, in vivo dosimetry should be performed in addition to treatment planning system computations.
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http://dx.doi.org/10.1007/s11604-012-0160-x | DOI Listing |
Clin Oral Investig
January 2025
Department of Restorative Dentistry - Endodontics, Faculdade de Odontologia de Piracicaba, Universidade Estadual de Campinas, Piracicaba, SP, Brazil.
Objectives: To investigate volumetric changes, in vivo biocompatibility, and systemic migration from eight commercial endodontic sealer materials in paste/paste, powder/liquid, and pre-mixed forms.
Materials And Methods: The sealers AH Plus Bioceramic, AH Plus Jet, BioRoot RCS, MTApex, Bio-C Sealer, Bio-C Sealer Ion+, EndoSequence BC Sealer and NeoSEALER Flo were studied. After characterisation by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), Raman spectroscopy and X-ray diffractometry (XRD), tubes were implanted in Wistar rats' alveolar bone and subcutaneous tissues.
Cancer Cell Int
January 2025
Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, Prague 4, 142 20, Czech Republic.
Medulloblastoma, the most prevalent brain tumor among children, requires a comprehensive understanding of its cellular characteristics for effective research and treatment. In this study, we focused on DAOY, a permanent cell line of medulloblastoma, and investigated the unique properties of DAOY cells when cultured as floating multicellular aggregates called spheres, as opposed to adherent monolayers. Through our comprehensive analysis, we identified distinct characteristics associated with DAOY spheres.
View Article and Find Full Text PDFBackground: In proton radiotherapy, the steep dose deposition profile near the end of the proton's track, the Bragg peak, ensures a more conformed deposition of dose to the tumor region when compared with conventional radiotherapy while reducing the probability of normal tissue complications. However, uncertainties, as in the proton range, patient geometry, and positioning pose challenges to the precise and secure delivery of the treatment plan (TP). In vivo range determination and dose distribution are pivotal for mitigation of uncertainties, opening the possibility to reduce uncertainty margins and for adaptation of the TP.
View Article and Find Full Text PDFEJNMMI Radiopharm Chem
January 2025
Department of Medicinal Chemistry, Uppsala University, Uppsala, 751 23, Sweden.
Background: Gastrin releasing peptide receptor (GRPR)-directed radiopharmaceuticals for targeted radionuclide therapy may be a very promising addition in prostate and breast cancer patient management. Aiming to provide a GRPR-targeting theranostic pair, we have utilized the Tc-99m/Re-188 radiometal pair, in combination with two bombesin based antagonists, maSSS-PEG2-RM26 and maSES-PEG2-RM26. The two main aims of the current study were (i) to elucidate the influence of the radiometal-exchange on the biodistribution profile of the two peptides and (ii) to evaluate the feasibility of using the [Tc]Tc labeled counterparts for the dosimetry estimation for the [Re]Re-labeled conjugates.
View Article and Find Full Text PDFMed Phys
January 2025
Netherlands Cancer Institute - Antoni van Leeuwenhoek hospital, NKI-AvL, Amsterdam, Netherlands.
Photodynamic therapy (PDT) is a treatment modality clinically approved for several oncologic indications, including esophageal and endobronchial cancers, precancerous conditions including Barrett's esophagus and actinic keratosis, and benign conditions like age-related macular degeneration. While it is currently clinically underused, PDT is an area of significant research interest. Because PDT relies on the absorption of light energy by intrinsic or administered absorbers, the dosimetric quantity of interest is the absorbed energy per unit mass of tissue, proportional to the fluence rate of light in tissue.
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