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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Transrectal ultrasound image processing for brachytherapy applications /

Sampath, Varsha. January 2006 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2006. / Typescript. Includes bibliographical references (leaves 48-51).
12

An analysis of dose effectiveness and incidence of late rectal complications of high dose-rate brachytherapy in the radical treatment of cervical cancer

Long, Deirdré January 2007 (has links)
Thesis (M. Tech.) -- Central University of Technology, Free State, 2007
13

MCNP5 Monte Carlo based dosimetry for the Nucletron Iridium-192 high dose-rate brachytherapy source with tissue heterogeneity corrections

Unknown Date (has links)
A Monte Carlo model has been developed using MCNP5 to simulate the Nucletron Ir-192 HDR source in order to investigate the influence of tissue heterogeneities on dose calculations compared to the dose in homogeneous water media, as it is typically calculated by brachytherapy Treatment Planning Systems (TPS). Validity of the simulation was verified in water medium in comparison with peer reviewed results using the dosimetric parameters recommended by AAPM, Task Group-43. The dose-rates in simulated prostate, bladder and rectum were compared to those obtained in the homogeneous water phantom. Based on the resulting dose differences, it is inferred that TPS algorithms for brachytherapy dose calculations overestimate the dose to tissues like prostate and bladder by up to 49%. A clinically relevant dose underestimation of 5.5% to the rectum was also found. We recommend that further investigation using actual patient CT data as input to the Monte Carlo simulation be performed. / by Ramsâes Herrera. / Thesis (M.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
14

Post implant dosimetric analysis for prostate brachytherapy

Haworth, Annette January 2005 (has links)
[Truncated abstract] Purpose: Permanent prostate brachytherapy (PPB) as a treatment option for prostate cancer requires implantation of 80-150 radioactive iodine-125 (I-125)
15

Intraoperative dosimetry analysis of prostate brachytherapy using transrectal ultrasound and x-ray fluoroscopy /

Tutar, Ismail B. January 2007 (has links)
Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 62-70).
16

Monte Carlo calculations for brachytherapy /

Taylor, Randle E. P., January 1900 (has links)
Thesis (M.Sc.) - Carleton University, 2006. / Includes bibliographical references (p. 99-104). Also available in electronic format on the Internet.
17

Rapid 3d seed reconstruction from incomplete data sets for image guided prostate brachytherapy /

Narayanan, Sreeram. January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 116-123).
18

Interface dosimetry for electronic brachytherapy Xoft Axxent intracavitary breast balloon applicators and fluorescence anisotropy imaging of quantum dots /

Segala, James J. January 2009 (has links)
Thesis (Ph.D.) -- University of Rhode Island, 2009. / Typescript. Includes bibliographical references (leaves 64-66).
19

Brachytherapy in cancer of the cervix : an African perspective

Mucheusi, Longino Kabakiza January 2012 (has links)
Thesis (MTech (Radiography))--Cape Peninsula University of Technology, 2012 / Introduction: Brachytherapy plays an essential role in the management of patients with cervical cancer. The high cervical cancer burden in Africa presents challenges with regard to provision and sustainability of these services. This study analysed treatment outcomes of two brachytherapy modalities, high dose rate (HDR) and low dose rate (LDR) intracavitary treatment for patients with cervical cancer, and evaluated the problems and challenges of the provision of these services within the African context. Methodology: The study was conducted using a case study approach with mixed methods at two sites in Africa, one in South Africa (Centre I) and the other in Kenya (Centre II). The study explored factors and issues affecting definitive radiotherapy of the patient with cervical cancer at the two sites with a focus on the brachytherapy treatment. The case study provided an opportunity to collect in-depth data consisting of quantitative and qualitative components that generated numeric and textual data. Treatment outcomes of one site treating with HDR and the other LDR intracavitary brachytherapy were retrospectively analysed for a maximum sample size of 193 (91%) patients in the HDR group and 49 (100%) patients in the LDR group. All patients were treated with external beam radiation therapy (EBRT) using parallel opposed beams (POP) for the patients that received LDR brachytherapy, and four field box technique or POP for those that received HDR brachytherapy. The linear quadratic formula was used to calculate the equivalent dose in 2 Gy fractions (EQD2) between the two groups.
20

Small field dose measurements with Gafchromic film

Underwood, Ryan John 09 April 2013 (has links)
Purpose: To examine the dosimetric characteristics of Gafchromic EBT3 film when measuring small fields of radiation, and compare it against other common radiation detectors. Methods and Materials: EBT3 film was placed in a solid water phantom and irradiated with 6MV photons, field sizes from 10x10cm2 down to 6x6mm2. The films were scanned with a Vidar DosimetryPRO Advantage Red scanner, and analyzed with RIT113 software. The films were also scanned at different orientations and times to quantify the discrepancies associated with scanning orientation and post-exposure darkening. The same fields were measured with a PTW TN30013 farmer chamber, an Exradin T1 cylindrical ion chamber, a PTW parallel plate ion chamber, and a Sun Nuclear Edge Detector (diode). Output factors were calculated for each detector and compared for accuracy. The output factors were measured from a Varian Clinac iX, Clinac 21EX, Trilogy, and TrueBeam; as well as a Novalis Tx. The outputs from different machines at different clinics were compared. Results: The EBT3 film and Edge Detector were the only detectors that succeeded in accurately measuring the output from all field sizes; the ion chambers were too large and failed for field sizes below 4x4cm2 due to volume averaging. The dose measured with the film increased by an average of 8.8% after one week post-irradiation. The dose measured was also reduced by an average of 4.4% by scanning the film in landscape orientation, as opposed to portrait orientation. It was shown that the output factors for the smallest field of 6x6mm2--successfully measured with film and diode--varied between 0.54-0.74 for five different machines at three different clinics. Conclusions: The feasibility of using Gafchromic EBT3 film to measure very small fields of radiation is confirmed. Of the other 4 detectors used, only the diode was shown to be capable of accurately measuring small fields of radiation. The need to optimize the film dosimetry process--including the time films are scanned post-irradiation, the consistency of the scanning orientation of the calibration and subsequent films, and the measurement procedure on the computer software--is highlighted.

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