Electrical Impedance Mammography (EIM) offers the potential for early detection of breast cancer in ways that conventional methods such as x-ray mammography and ultrasound mammography fail. EIM involves passing low level alternating currents through the breast tissues via a number of surface electrodes placed on the skin, and monitoring the surface voltages produced as a result. Images of the complex impedance of the internal tissues are formed by solving the mathematical equations governing the relationships between current, voltage and impedance in a volume conductor. However, due to inherent ill-conditioning within these equations the image formation process is inefficient and leads to poor resolution images. The work presented here is a simulation study aimed at investigating the factors that affect the conditioning of the underlying equations in order to gain a better understanding of how the image resolution might be maximised. The first part of the investigation focuses on 2-dimensional EIM, and in particular the effect of increasing the number of electrodes used. The second part explores 3-dimensional imaging and concentrates on the interrelated effects on image quality of breast shape, electrode placement and the current and voltage patterns applied to the electrodes. In doing so an algorithm for modelling breast imaging in 3-dimensions is developed and a number of original approaches to data collection strategies are proposed and tested. As well as optimising image performance, one of the key considerations throughout the study is the spatial variance of the resolution, since it is desirable to have an imaging modality which is not biased to any particular region of the breast. In conclusion, a new electrode placement methodology is proposed which promises an improvement in resolution over any of the existing ElM systems, and has the added benefit of easily adapting to a wide range of breast shapes and sizes

World Health Organization (WHO) reported that breast cancer is the top cancer in women both in the developed and the developing countries. Although breast cancer is thought to be a disease of the developed countries, the incidence of breast cancer is increasing in developing countries, where the disease has becoming the lead ing cause of death. WHO added that the high mortality rates in less developed countries is mainly causes by majority of cases are diagnosed in late stages preventing curable treatment, as well as by the lack of adequate diagnosis and treatment facilities. Therefore, early tumour detection is very important in breast cancer management being able to improve the surviving rate. Many techniques to improve the detection of tumours in the breast have been developed in the last few years. Th is study is focusing on the dual-energy technique of contrast-enhanced digital mammography (CEDM) to aid in the detection and characterization of breast lesions. Standard dual-energy (K-edge subtraction) methodology requires two separate acquisitions to obtain two images, below and above the K-edge of a given contrast agent, and is typically implemented with a monochromatic X-ray source. This work in mammography proposes an approach using a polychromatic beam, providing for clinical applications with X-ray tubes. In particular, with a polychromatic beam produced by a microfocal X-ray source, this work is aimed at assessing the feasibility of K-edge subtraction (KES) mammography carried out in conjunction with an iodine-based contrast agent. Spectroscopic information is obtained using pixellated spectroscopic detectors.

This thesis examines and explores women's mammography screening experiences and the factors influencing women's screening behaviours and choices. The sample consisted of Greek women who were recruited from women's organizations in Athens. 189 women completed a survey questionnaire about their values and beliefs in relation to mammography screening, 33 of whom subsequently underwent an in-depth interview to explore their experiences of mammography screening and their decision-making processes. According to the findings, women's mammography screening behaviour depended to a great extent on the quality and nature of their interactions within their social networks. Thus, the quality of information and meanings derived from these interactions was what determined women's behaviour. Family, close friends and doctors appeared to be important in the formation of women's beliefs, perceptions, emotions (fear of cancer) and behaviour in relation to breast screening. Interestingly, fear of cancer had an opposing effect towards their screening behaviour. A tentative model is presented, which attempts to explain the way these influences affect beliefs, perceptions and mammography screening behaviour, using elements of existing behavioural models. Further exploration of the influential factors and associations identified in this study is required.