Propagation of measurement noise through backprojection reconstruction in electrical impedance tomography.
A framework to analyze the propagation of measurement noise through backprojection reconstruction algorithms in electrical impedance tomography (EIT) is presented. Two measurement noise sources were considered: noise in the current drivers and in the voltage detectors. The influence of the acquisition system architecture (serial/semi-parallel) is also discussed. Three variants of backprojection reconstruction are studied: basic (unweighted), weighted and exponential backprojection. The results of error propagation theory have been compared with those obtained from simulated and experimental data. This comparison shows that the approach provides a good estimate of the reconstruction error variance. It is argued that the reconstruction error in EIT images obtained via backprojection can be approximately modeled as a spatially nonstationary Gaussian distribution. This methodology allows us to develop a spatial characterization of the reconstruction error in EIT images.
Frangi
Alejandro F
AF
Departamento de Ingeniería Electrónica y Comunicaciones, Universidad de Zaragoza, Spain. afrangi@posta.unizar.es
Riu
Pere J
PJ
Rosell
Javier
J
Viergever
Max A
MA
D000465:Algorithms; D016477:Artifacts; D003198:Computer Simulation; D017097:Electric Impedance; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008954:Models, Biological; D015233:Models, Statistical; D016011:Normal Distribution; D019047:Phantoms, Imaging; D012680:Sensitivity and Specificity; D013269:Stochastic Processes; D013909:Thorax / Q000033:anatomy & histology / Q000502:physiology; D014054:Tomography / Q000295:instrumentation / Q000379:methods*