סמינר המחלקה להנדסה ביו רפואית
אביחי רון
תלמיד המחלקה להנדסה ביו רפואית לתואר שני ירצה בנושא:
Monitoring bone mineral density (BMD) of the wrist –A parametric EIT simulation
Our goal is to validate the feasibility of monitoring wrist bone mineral density at home using a Parametric Electric Impedance Tomography (EIT) simulation.
Introduction: BMD testing is a vital component in the diagnosis and management of Osteoporosis. It is an excellent predictor for future fracture risk. Furthermore, deterioration of BMD in peripheral sites is a good predictor for fractures risk at the hip. Hip fractures are followed by an increased risk of future fractures. Approximately 20 percent of hip fracture patients require long-term nursing home care, and only 40 percent fully regain their pre-fracture level of independence.
EIT is a Non-invasive bio-impedance measurement. The method is used for reconstructing the electrical and dielectric properties of the body. "Injected current method" uses surface electrodes array for current injection and potential measurement. By solving the backward problem by using a computerized model of the body we can then achieve a reconstruction. At high current frequencies we see a good correlation between the BMD of the bone and its electrical properties- conductivity [S/m] and Permittivity [F/m].
Methods: We solve the forward problem of the developing potential around the wrist due to current injection by using a Matlab numerical simulation of an adult human phantom (XCAT, Duke Uni.). The inverse problem is solved by building a lookup table of different bone densities which represent different disease stages.
Results: We examine the differences in potentials on the different electrodes between different stages of the disease. We found a high sensitivity for deterioration of the cortical bone, 80 percent change between a healthy stage (0.32 g\cm3 BMD) and Osteoporosis stage (0.16 g\cm3 BMD), 18 percent sensitivity for deterioration of the cancellous bone and 100 percent sensitivity for the simultaneous deterioration of both parts of the bones. The measurement is highly robust to electrical noises but the robustness to deposition of the electrode is limited to 1cm.
Conclusion: The technology may provide a simple method for evaluating changes in the BMD of the wrist.
העבודה נעשתה בהנחיית פרופ' שמעון עבוד , המחלקה להנדסה ביו-רפואית, אוניברסיטת תל-אביב
ההרצאה תתקיים ביום ראשון 29.3.15, בשעה 14:15,
בחדר 315, הבניין הרב תחומי, אוניברסיטת תל אביב
