Research Interests

Research Interests

Our lab's interests primarily focus on projects related to breast cancer. Our lab has developed a novel Electrical Impedance Tomography (EIT) prototype (former students Mehran Goharian, Arv Jegatheesan and Kenrick Chin). EIT is a technique where a current is injected on alternating pairs of electrodes and voltages measured on the remaining surface electrodes are used to generate an image of the conductivity distribution inside a volume. Our 48 electrode prototype will be used primarily to study phantoms, however the ultimate goal is to develop a tool to detect breast cancer.

Dost and Cassie are working on enhancing the hardware and software of this prototype.

Ian on the other hand is working with some of our local physicians to obtain samples of breast tissue from biopsy and reduction surgeries. These samples are being measured in network impedance analyzers (Agilent) to determine the frequency dependent impedance of the various tissues. The impedance of the normal healthy and diseased breast tissue will be used to make phantoms that mimic the real breast. In collaboration with Dr. Gord Campbell at the NRC, this information will be incorporated into a Poly-vinyl alcohol cryogel phantom that can be made to mimic a variety (MRI, electrical, elastic, ultrasound, density) of tissue properties. This phantom can then be used to test the EIT system.

Farukh has been working on implementing Magnetic Resonance Elastography (MRE) – a technique that enables a measure of the elasticity of tissue – on our Siemens MRI platform. This has involved the construction of a tool to vibrate the tissue, and sequence programming. Ultimately the goal is to use this technique to gain additional contrasts in MRI images, for example in identifying breast tumours.

Kyle Wilson’s work is the use of NIR in breast cancer detection. The ComfortScan™ system uses a soft membrane to compress the breast during a scan. The breast is imaged using near infra-red (NIR) light which is not a form of ionizing radiation. Images are taken before and after compression with the scan taking approximately 1 minute. Angiogenesis is the growth of new blood vessels and it occurs during the formation of a tumour. With an increase in new blood vessels there is an increase in blood flow. Therefore the assumption is that an increase in blood flow is indicative of the presence of a tumour. In theory, the tumour vasculature collapses under compression. When the images before and after compression are subtracted, these areas of malignant tissue will be enhanced. This system is inexpensive, quick, and safe (no ionizing radiation) and therefore it would be beneficial to explore its potential use in a clinical setting. The hemoglobin concentration, oxygen saturation, water fraction, scattering amplitude, and scattering power were all measured. Future work will involve: i) continuing patient recruitment until the required sample size is reached (100 patients), ii) analyzing all data collected, iii) writing a publication on the preliminary analyzed data.

Ted’s work is focussed on clinical applications of ultrasound physics and instrumentation. Research interests are related to advanced ultrasound instrumentation including, three-dimensional imaging techniques, advanced signal processing techniques and their impact on clinical applications. Current research involves the development of an improved imaging strategy using a Standardized Assessment in Real-Time (START) technique for the detection of congenital heart defects during the second trimester obstetric screening exam.

Publications

Recent Publications

1.  M Goharian, A Jegatheesan, GR Moran, “Dogleg trust-region application in electrical impedance tomography,” Journal of Physiological Measurement 2007; 28:555-572.

2.   M Goharian, MJ Bruwer, A Jegatheesan, GR Moran, JF MacGregor, A Novel Approach for EIT Regularization Via Spatial and Spectral Principal Component Analysis, Physiol. Meas. 2007; 28: 1001–1016.

3. M. Goharian, G.R. Moran, K. Wilson, C. Seymour, A. Jegatheesan, M. Hill, R.T. Thompson, and G. Campbell,  “Modifying the MRI, Elastic Stiffness and Electrical Properties of Polyvinyl Alcohol Cryogel Using Irradiation,” Nuclear Instruments and Methods in Physics Research B 263 (2007) 239–244.

4.  Mat Mercuri, Gerald R. Moran, Leslie Gauthier, Tej Sheth, James L. Velianou and Madhu K. Natarajan.  “Radiation Dose in Interventional Cardiology Procedures: Urgent Need for Monitoring Dose and Establishing Diagnostic Reference Levels,” Healthcare Quarterly 2007; Vol.11 No.1:74-81.

5.  C. Mothersill, G.R. Moran, F. McNeill, J.A. Lemon, J. Denbeigh, W. Prestwich, C.B. Seymour, “A role for electromagnetic fields in the induction of bystander signals?” Dose Response 2007; 5(3):214-229.

6.  M Goharian, M Soleimani, A Jegatheesan, GR Moran, “Regularization of EIT Problem Using Trust Region Subproblem Method,” Accepted as a conference paper by the 13th International Conference on Electrical Bioimpedance, Aug 29-Sept 2 2007.  IFMBE Proceedings 17, pp. 400–403, 2007.

7. Ted Scott, Hans Swan, Gerald Moran, Tapas Mondal, Judy Jones, Karm Guram, Jaime Huff, “Increasing the Detection Rate of Normal Fetal Cardiac Structures: A Real-Time Approach”, Journal of Diagnostic Medical Sonography 2008; 24(2):63-71.

8. M Goharian, M. Soleimani, A Jegatheesan, K Chin, G Moran,“A DSP based Multifrequency 3D Electrical Impedance Tomography System,” Annals of Biomedical Engineering 2008; 36(9):1594-1603.

In Press

1.  M. Goharian, M. Soleimani, G. Moran, “A Trust Region Sub Problem For 3d Electrical Impedance Tomography Inverse Problem Using Experimental Data,” Accepted by Journal of Electromagnetic Waves and Applications (JEMWA) May 2009

Submitted Manuscripts

1.         C. Lemaire, G. Moran, H. Swan.  “The Impact of Audio/Visual Systems on Pediatric Sedation in Magnetic Resonance Imaging,” Submitted to JMRI, February 2009.

2.         G.R. Moran, R. Chandrani, K. Morreale, M.L. Schmuck, G. Norman, “Wireless DR Solution Improves Workflow With Improved Image Quality Compared To CR,” Submitted to CARJ, March 2009.

Students Supervised

Students Supervised

• Unavailable

Courses Taught

Courses Taught

• Medical Physics 770
• MRI portion of Medical Physics 4T3