No description available.

Access to abstract permanently restricted to Ball State community only. / Literature review -- Interaction of radiation with matter -- Radiation dosimetry -- Materials and methods -- Results -- Discursion. / Access to thesis permanenty restricted to Ball State community only. / Department of Physics and Astronomy

Doctor of Health Science / It is well documented that for prostate cancer patients undergoing radiation therapy there is a correlation between target volume displacement and changes in bladder and rectal volumes. However, these studies have used a methodology that has captured only a subset of all treatment positions. This research used daily Computer Tomography (CT) imaging to comprehensively assess organ volumes, organ motion and their effect on dose, something that has never been performed previously, thus adding considerably to the understanding of the topic. Daily CT images were obtained using a Siemens Primus Linear Accelerator equipped with an in-room Somatom CT unit in the accelerator suite, marketed as ‘Primatom’, to accurately position the patient prior to treatment delivery. The internal structures of interest were contoured on the planning workstation by the investigator. The daily volume and location of the organs were derived from the computer to assess and analyse internal organ motion. The planned dose distribution was then imported onto the treatment CT datasets and used to compare the planned dose to i) the actual isocentre, where the isocentre was actually placed for that fraction, ii) the uncorrected isocentre, by un-doing any on-line corrections performed by the treatment staff prior to treatment delivery, and iii) the future isocentre, by placing the isocentre relative to internal organ motion on a daily basis. The results of this study did not confirm a statistically significant decrease in rectum volumes over time (hypothesis 1), however large fluctuations in bladder volume were confirmed (hypothesis 2). Internal organ motion for the rectum and bladder was demonstrated to be related to organ filling. Ideal planning volumes for these organs have been reported to minimise systematic and random uncertainty in the treatment volumes. An observed decrease in prostate volume over time, a systematic uncertainty in the location of the prostate at the time of the planning CT scan and a significant relationship between prostate centre of volume and rectum and bladder volumes has resulted in a recommendation that patients should be re-scanned during treatment to ensure appropriate clinical target volume coverage. A significant relationship between rectal and bladder volumes and the dose delivered to these organs was found (hypothesis 3). The dose delivered to the planning target volume was not related to the rectal or bladder volumes, although it was related to the motion of these organs. Despite these results only minimal effects on the dose delivered to any of the three isocentres occurred, indicating that the planned dose was accurately delivered using the methodology presented here (hypothesis 4). However the results do indicate that the patient preparation instructions need to be improved if margins are to be reduced in the future. It is unrealistic to assume that Image Guided Radiation Therapy will ever become routine practice due to infrastructure costs and time limitations. This research will inform radiation therapy centres of the variables associated with prostate cancer treatment on a daily basis, something that has never before been realistically achievable. As a result centres will be able to devise protocols to improve treatment outcomes.

[Truncated abstract] Purpose: Permanent prostate brachytherapy (PPB) as a treatment option for prostate cancer requires implantation of 80-150 radioactive iodine-125 (I-125)

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.

Thesis (M.Tech.: Radiography) - Dept. of Radiography, Durban Institute of Technology, 2003 1 v. (various pagings) / Cancer is an inexorably progressive disease and a favourable outcome in its management often depends on early intervention (Mackillop, Zhou and Quirt, 1995: 532). Early detection of the disease is therefore important for a favourable outcome to be achieved. When the disease is diagnosed at a late stage, the treatment that is offered is only palliative. Palliative treatment is only offered with the aim to relieve the local symptoms of advanced disease. The treatment intent is therefore not curative but only to give the patient a better quality of life, which sometimes is not possible especially for very advanced disease. In KwaZulu-Natal the incidence of Zulu speaking patients presenting with a late stage disease to the major cancer treatment centres is very high with the result that the majority of these patients can only be offered palliative treatment (Pervan, Cohen and Jaftha, 1995 : 162). Aim of the study is to investigate the factors that contribute to the late presentation of rural Zulu patients with cancer to the two major provincial cancer treatment centers in KwaZulu-Natal (prior to December 2002).

published_or_final_version / Community Medicine / Doctoral / Doctor of Philosophy

published_or_final_version / abstract / Medicine / Master / Doctor of Medicine

No description available.

The use of quality of life instruments to evaluate the effect of cancer and its treatment on individuals has increased but the process by which the patient comes to make these quality of life evaluations has not been addressed. Earlier studies have shown the reporting of physical symptoms and the evaluation of one's health to be related to negative affect. The purpose of this study was to investigate whether the relationship between negative affect and the evaluation of ones health would remain the same in a group of cancer patients, when a major disease and treatment symptom, fatigue was controlled for. The current study found no relationship between negative affect and the evaluation of health once fatigue was controlled for. Negative affect and fatigue were found to be moderately correlated and fatigue accounted for a large proportion of the variance in the quality of life domains of physical, functional and emotional well-being. Both empirical and theoretical issues are discussed. / Department of Counseling Psychology and Guidance Services