Spelling suggestions: "subject:"diagnostic imaging -- south africa"" "subject:"diagnostic imaging -- south affrica""
1 |
Effect of exposure charts on reject rate of extremity radiographsKalondo, Luzanne January 2010 (has links)
This study discusses reject film analyses (RFAs) before and after the implementation of a quality improvement intervention. RFAs were undertaken to investigate the effect of the introduction and use of exposure charts (ECs) on department and student reject rates of extremity radiographs. Methods: A quantitative comparative pre and post-treatment research design was used. Data was collected from the x-ray departments of two training hospitals in Windhoek, Namibia over a five month period. A retrospective RFA was conducted to determine the department and student reject rates for both departments before intervention. Emphasis was placed on exposure related reject films. ECs were compiled and introduced at Katutura State Hospital (venue B) by the researcher. The students were instructed to use these charts. At Windhoek Central Hospital (venue A) no ECs were used. A prospective RFA was conducted to establish department and student reject rates at both hospitals after the intervention at venue B. Results: During the retrospective phase the department reject rate for venue A was 21 percent while the student reject rate was 23 percent. At venue B 24 percent and 26 percent were scored respectively. Students at venue A produced rejected radiographs due to overexposure (49 percent) and underexposure (23 percent), whilst 37 percent was recorded for both causes at venue B. At venue A, 35 percent of films were rejected due to incorrect mAs selection, at venue B the figure was 42 percent. Undiagnostic radiographs due to inaccurate kV selection comprised 62 percent for venue A and 59 percent for venue B. During the prospective phase the department reject rate for venue A was 20 percent and that of the students was 19 percent. For venue B 12 percent and 11 percent were scored respectively. At venue A radiographs rejected due to over and underexposure were 43 percent and 33 percent respectively while those at venue B were 33 percent and 34 percent. Incorrect mAs selection caused 33 percent of discarded films at venue A and 38 percent at venue B. The figures for inaccurate kV selection were 68 percent and 62 percent for venues A and B. Conclusions: The introduction and use of ECs lowered the student reject rate at venue B in the prospective phase.
|
2 |
2D brachytherapy planning versus 3D brachytherapy planning for patients with cervical cancerGovender, Natalie 05 March 2015 (has links)
Submitted in fulfillment of the requirements of the degree of the Master of Technology : Radiography, Durban University of Technology, 2014. / Research Aims
The purpose of this study is to compare 2D HDR Brachytherapy planning and 3D HDR Brachytherapy planning in terms of dose distribution in order to accurately determine bladder and rectal doses. Further research questions were explored to determine whether relationships existed between Computer Tomography volumes and bladder and rectum dose.
Methodology
The 30 female patients that volunteered for the study were conveniently selected. Their age and ethnic group did not contribute to their selection.
All participants were prepared for cervical HDR Brachytherapy. The Brachytherapy templates were computer generated and treatments were given based on the templates. They then had a Computer Tomography (CT) scan (3D data set) of the pelvis. The computer generated templates for 2D Brachytherapy planning were applied to the CT data set i.e. 2DBP. The plans were optimised to take into consideration the dose to the bladder and the rectum i.e. 3DBP. The 2DBP and the 3DBP were then evaluated in order to determine which method of planning yielded more acceptable dose distributions to the bladder and rectum.
Results
Significant differences in dose distribution were noted on comparison of 2DBP and 3DBP. A significant relationship was noted in respect of bladder mean dose and rectum mean dose. 3DBP proved to be more efficient in yielding lower mean dose to the bladder and the rectum. Whilst a significant relationship was noted in respect of bladder maximum dose, an insignificant relationship was noted for rectum maximum dose. Therefore, the efficiency of 3DBP to yield lower bladder maximum dose was established but its efficiency to yield lower rectum maximum dose is questionable. This has implications for the management of patients’ with cervical cancer who require cervical Brachytherapy.
Recommendations
It is imperative that imaging modalities be used for the accurate planning of cervical Brachytherapy. This study recommends that CT be used for HDR Brachytherapy planning by proving its greater efficiency compared to template planning.
|
Page generated in 0.1082 seconds