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| Simulation and Experimental Research on the Impact of Skull in Magnetic Induction Tomography Signal Detection |
| School of Electrical Engineering,Shenyang University of Technology, Shenyang 110870, China |
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Abstract The aim of this paper is to study the effect of skull to magnetic induction tomography (MIT) signal detection through simulation and experiments. Firstly, a spherical brain model of three layers was established using Comsol software to simulate the effects of the skull conductivity to MIT signal detection. And then a multichannel magnetic induction tomography experimental system which consists of solenoid coil, rear circuit and data receiving apparatus was established, and a hierarchical model of cerebral hemorrhage was made of agar and NaCl solution which has a similar conductivity distribution with the real brain. The diameter of the model is 158 mm. Finally, in the two models with skull and without skull, the phase change of no lesion and different locations of simulating lesions were measured. The distance between the model center and detection coil is 85 mm. From the results, what can be seen is that, when the model with no lesion and lesions were on the coordinates of (-40,0), (0,0) and (40,0) of the X-Y plane, the proportion of the phase change between the models with and without skull is 0.57, 0.59, 0.42, 0.61 respectively. The coordinates of (-40,0) and (40,0) represent the position which has a distance of 45mm from incentive coil to y axis and a distance of 45mm from Y axis to incentive coil respectively. When there is a lesion, the change trend of the data in the model with and without skull is same, which means that the maximum appears on the coordinate of (-40,0), the second appears on the coordinate of (0,0), and the smallest appears on the coordinate of (40,0). The results show that, the skull has an effect of attenuation on the size of MIT signals, but the changing trend of measured data is not changed. The results also indicate that the image detection of intracranial lesions can be achieved without a record and contact using high precision hardware detection system in practical applications.
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