Breast tumour detection using a flat 16 element array

A new experimental prototype of a breast cancer detection technique using real aperture multi-static radar is presented. The system comprises a fully-populated 16 element flat array and an associated system to switch between different transmit and receive elements. 3D images are produced using backscatter signals from a synthetic breast phantom. After suppression of skin reflections, initial images demonstrate the successful detection of 4-mmdiameter tumours

Breast cancer tumour detection using microwave radar techniques

A breast cancer detection technique using multi-static radar is proposed herein. Images of a breast tumour are produced using this technique, with backscatter data. A wideband antenna design suitable for a breast cancer detection system is also described. Practical measurements are performed using a network analyser and a pair of antennas that are used to simulate an array. These initial images demonstrate the successful detection of a tumour phantom immersed in a liquid phantom with similar dielectric properties as the breast tissues

Numerical analysis of microwave detection of breast tumours using synthetic focussing techniques

Microwave detection of breast tumours is a non-ionising and potentially low-cost and more certain alternative to X-ray mammography. Analogous to ground penetrating radar (GPR), microwaves are transmitted using an antenna array and the reflected signals, which contain reflections from tumours, are recorded. The work presented here employs a post reception synthetically focussed detection method developed for land mine detection (R. Benjamin et al., IEE Proc. Radar, Sonar and Nav., vol. 148, no.4, pp. 233-40, 2001); all elements of an antenna array transmit a broadband signal in turn, the elements sharing a field of view with the current transmit element then record the received signal. By predicting the path delay between transmit and receive antennas via any desired point in the breast, it is then possible to extract and time-align all signals from that point. Repeated for all points in the breast, this yields an image in which the distinct dielectric properties of malignant tissue are potentially visible. This contribution presents a theoretical evaluation of the breast imaging system using FDTD methods. The FDTD model realistically models a practical system incorporating wide band antenna elements. One major challenge in breast cancer detection using microwaves is the clutter arising from skin interface. Deeply located tumours can be detected using windowing techniques (R. Nilavalan et al., Electronics Letters, vol. 39, pp. 1787-1789, 2003); however tumours closer to the skin interface require additional consideration, as described herein

Microwave detection of breast tumours

Copyright @ 2003 European Bioelectromagnetics Association

Wideband microstrip patch antenna design for breast cancer tumour detection

A patch antenna is presented which has been designed to radiate into human breast tissue. The antenna is shown by means of simulation and practical measurement to possess a wide input bandwidth, stable radiation patterns and a good front-to-back ratio. Consideration is also given to its ability to radiate a pulse, and in this respect it is also found to be suitable for the proposed application

Experimental investigation of real aperture synthetically organised radar for breast cancer detection

Breast cancer is the most common cancer in woman, and early detection increases the likelihood of successful treatment and long-term survival screen film mammography is currently the most effective method for detecting breast tumours, however this technique suffers from relatively high false negative and positive detection rates, and it involves uncomfortable compression of the breast. This paper presents the experimental investigation of real aperture synthetically organised radar for breast cancer detection. The work presented herein originated as a theoretical study employing FDTD models. This contribution presents subsequent experimental validation using a mechanically-scanned 2 element antenna array and a breast phantom consisting of synthetic biological materials

A wideband planar antenna for in-body imaging

Breast cancer is the most common cancer in women. X-ray mammography is currently the most effective detection technique, however it suffers from a relatively high missed- and false-detection rates, involves uncomfortable compression of the breast and also entails exposure to ionizing radiation. Microwave detection of breast tumours is a potential non-ionising alternative being investigated by a number of groups. In these microwave-based systems, in a similar fashion to ground penetrating radars, microwaves are transmitted from an antenna or antenna array, and the received signals, which contain reflections from tumours, are recorded and analysed. A pre-requisite for all of these systems is a suitable antenna. This contribution presents in detail for the first time, an inexpensive, wideband, planar antenna design, specifically designed to radiate into breast tissue

The development, validation and standardisation of a questionnaire measuring an Auditing teaching-learning intervention at a SAICA-accredited university

Questionnaires are widely used in the Accountancy field as a data collection instrument. However, previous studies have contentious views on the reliability of questionnaires in academic studies. This study describes the development of a custom-made questionnaire to evaluate the effectiveness of a teaching-learning intervention, the Audit Cube, designed to affect the knowledge, skills, attitudes and values of Auditing of B.Com. honours students in the Accountancy field at a SAICA-accredited university. The questionnaire was distributed to 156 university honours students, whereafter it was validated and standardised. Most of the extracted factors indicated a reliability level higher than 0.9, signifying that the constructs were suitable to address the project’s research question and that the questionnaire is valid. In conclusion, this study found that the use of questionnaires in academic studies is deemed reliable if a standardised process is followed in its development. Consequently, the study suggests that custom-made questionnaires should undergo factor analysis to prove the instrument’s validity prior to reporting on the findings. The findings of this study may be useful to academics in providing guidelines in developing their own data collection instrument to measure the effectiveness of a teaching-learning intervention and may also support the use of questionnaires by researchers in the teaching-learning environment