Planar MIT Sensor Array with Gradiometers for Local Hemorrhage Detection

Magnetic induction tomography (MIT) is a promising technology in medical imaging due to its non-radioactive, non-invasive and non-contact properties. To realize the local detection of intracranial hemorrhage with small volume, a planar MIT sensor array with gradiometers is proposed. The local sensitive region was defined and the sensitivities of the planar array with gradiometers and the planar array with Bx sensors were compared. With 3D anatomical head model, the phase response of the hemorrhages in different volumes under the two sensor arrays was investigated. The evaluation indexes: sensitivity intensity A and useful signal to background signal ratio UBR were introduced for evaluating the performance of the sensor arrays in hemorrhage detection. In the local sensitive region, the sensitivity intensity of the planar sensor array with gradiometers is 3 times larger than the Bx sensors. Furthermore, for the 2 mL hemorrhage, the UBR under the structure of gradiometers is 6 times larger than that under the structure of Bx sensors. The results indicate that the planar sensor array with gradiometers can effectively reduce the effect of normal head tissues and improve the accuracy in hemorrhage detection.