VOL. 10, NO. 15, AUGUST 2015 ISSN 1819-6608 ARPN Journal of Engineering and Applied Sciences © 2006-2015 Asian Research Publishing Network (ARPN). All rights reserved. www.arpnjournals.com 6230 A REVIEW ON BREAST ELECTRICAL IMPEDANCE TOMOGRAPHY CLINICAL ACCURACY Zain N. M. 1 and Kanaga K. C. 2 1 School of Medical Imaging, Faculty of Health Sciences, KPJ Healthcare University College, Nilai, Malaysia 2 Faculty of Health Sciences, Universiti Kebangsaan Malaysia (UKM), Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia E-Mail: norhayati@kpjuc.edu.my ABSTRACT Electrical Impedance Tomography (EIT) is a non-invasive procedure using electrical impedance to image the human breast. Due to its mobility and using non-compression technique it is appealing to patients. This scanning device does not emit any ionizing radiation thus it can be done on pregnant women by means of no age limit. Since the EIT has play some supplementary function in the breast imaging, a lot of research on its clinical accuracy has been done. Therefore, the aim is to carry out a review of EIT clinical accuracy and assess the quality of journal by using Quality Assessment of Diagnostic Accuracy Studies (QUADAS) criteria. The journals that assess the sensitivity were search through various databases and the clinical accuracy of EIT in each journal is recorded. The review shows that the range sensitivity (Sn) of EIT system to human breast in ten journals was between 17% and 94.6%. The range of specificity (Sp) is between 49% and 97.1%. The negative (NPV) and positive predictive value (PPV) is between 74% and 98%; 4% and 73.3% respectively. The accuracy (ACC) of EIT is between 69% and 80.5%. This value is found to be supported that EIT can be used as an adjunct screening technique for human breast. Keywords: electrical impedance tomography, diagnostic accuracy, breast cancer. INTRODUCTION Breast cancer is considered to be the final outcome of multiple environmental and hereditary factors and therefore the best way to prevent mortality is by early detection. Nowadays, there are various modalities for diagnostic imaging such as magnetic resonance imaging (MRI), computed tomography (CT) scan and mammography. Between all the modalities, mammography has become a gold standard for breast imaging (Tinberg et al. 2011). Mammography has become an effective imaging tool for detecting early stage of carcinomas in the breast (Park et al. 2007). However it uses ionizing radiation and causes discomfort to patients due to compression of the breast tissues (Prasad et al., 2008). Attenuation of the tissues using radiation enables the inner structure of breast tissues to be visualized on the mammogram tissues (Zou and Guo, 2003). Other modalities namely ultrasound is used as an adjunct to mammography for the differentiation of potentially suspicious breast lesions (Subbhuraam et al. 2011). Breast imaging together with other more advanced complementary methods focuses on improving early detection of the cancer cells and reduces the occurrence of missed cancers (Houssami et al. 2009). One suggested method is electrical impedance tomography (EIT). A potentially, new noninvasive diagnostic technique based on different electrical storage potential of normal and pathologically altered tissues allowing image differences in the tissue conductivity and permittivity inferred from the body surface electrical measurements. EIT consists of a hand-held scanning probe and a computer screen that displays two-dimensional images of the breast. The EIT examination is performed with the subject recumbent, with both arms raised above the head. The purpose of this position is to flatten the breast as much as possible, allowing optimal contact of the flat surface of the scan probe with the breast tissue. The transducer is firmly pressed against the breast and the probe is moved in such a way as to remove air bubbles and to ensure good contact with the breast. Due to its mobility and utilizing a non-compression technique it is appealing to patients. This scanning device does not emit any ionizing radiation thus it can be done on pregnant women by resulting in no age limit (Abdi and Liatsis, 2011). The aim of this review is to systematically collect journals on the clinical accuracy of breast EIT in detecting breast cancer. The journals then will be evaluated according to the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) criteria. METHODOLOGY The literature search for relevant references was performed by using two different databases, which included Medline and Scopus to cover publications between 2000 and 2015. Archived journal are assessed through the University Kebangsaan Malaysia library database and were extracted based on the criteria mentioned bellow. The terms used for identification of references were ‘electrical impedance tomography’; ‘breast cancer’; and ‘sensitivity’. The search was limited to include all the studies that had been published in the English language and related to the clinical accuracy of EIT specifically on human breast tissue. Exclusion criteria included experimental studies, studies that did not highlight details on sensitivity (Sn) on overall performance of breast EIT and any review studies. Additionally those which full text could not be obtained were excluded. Comparisons of the sensitivity in each journal were performed based on overall performance.