title: Parametric electrical impedance tomography for measuring bone mineral density in the pelvis using a computational model.
abstract: Osteoporosis is defined as bone microstructure deterioration resulting a decrease of bone's strength. Measured bone mineral density (BMD) constitutes the main tool for Osteoporosis diagnosis, management, and defines patient's fracture risk. In the present study, parametric electrical impedance tomography (pEIT) method was examined for monitoring BMD, using a computerized simulation model and preliminary real measurements. A numerical solver was developed to simulate surface potentials measured over a 3D computerized pelvis model. Varying cortical and cancellous BMD were simulated by changing bone conductivity and permittivity. Up to 35% and 16% change was found in the real and imaginary modules of the calculated potential, respectively, while BMD changes from 100% (normal) to 60% (Osteoporosis). Negligible BMD relative error was obtained with SNR>60 [dB]. Position changes errors indicate that for long term monitoring, measurement should be taken at the same geometrical configuration with great accuracy. The numerical simulations were compared to actual measurements that were acquired from a healthy male subject using a five electrodes belt bioimpedance device. The results suggest that pEIT may provide an inexpensive easy to use tool for frequent monitoring BMD in small clinics during pharmacological treatment, as a complementary method to DEXA test.
authors.affiliation: Department of Biomedical Engineering, Faculty of Engineering, Tel-Aviv University, Tel-Aviv 69978, Israel.
authors.forename: Shani
authors.initials: S
authors.lastname: Kimel-Naor
authors.affiliation: Department of Biomedical Engineering, Faculty of Engineering, Tel-Aviv University, Tel-Aviv 69978, Israel. Electronic address: abboud@post.tau.ac.il.
authors.forename: Shimon
authors.initials: S
authors.lastname: Abboud
authors.affiliation: Department of Geriatric Rehabilitation, Sheba Medical Center, Israel.
authors.forename: Marina
authors.initials: M
authors.lastname: Arad
mesh_terms: D015519:Bone Density; D003198:Computer Simulation; D017097:Electric Impedance; D006801:Humans; D008954:Models, Biological; D010388:Pelvis / Q000000981:diagnostic imaging* / Q000502:physiology*; D014054:Tomography
keywords: Electrical impedance tomography; Monitoring bone mineral density; Osteoporosis; Pelvis model; Simulation study; Tissue electrical parameters