Quantitative evaluation of the performance of different electrical tomography devices

Two widely used electrical tomography systems, the Sheffield Mark I and the DAS-01P, were quantitatively evaluated and compared to the newly developed Goe-MF system. The performance was quantified using a hardware phantom whi ch closely matches the real input and transfer impedances of the human thor ax and allows measurements equivalent to different states of lung inflation . Our results demonstrate that adequate averaging is necessary for noise re duction for the Mark I and especially for the DAS-01P system to get meaning ful results even in visualizing maximal respiratory manoeuvres. The Goe-MF system showed a notably improved signal-to-noise ratio which allows also dy namic measurements at low levels of lung volume changes, e.g., in intensive care lung injury patients.