Frequency-difference MIT imaging of cerebral haemorrhage with a hemispherical coil array: numerical modelling.
The feasibility of detecting a cerebral haemorrhage with a hemispherical MIT coil array consisting of 56 exciter/sensor coils of 10 mm radius and operating at 1 and 10 MHz was investigated. A finite difference method combined with an anatomically realistic head model comprising 12 tissue types was used to simulate the strokes. Frequency-difference images were reconstructed from the modelled data with different levels of the added phase noise and two types of a priori boundary errors: a displacement of the head and a size scaling error. The results revealed that a noise level of 3 m degrees (standard deviation) was adequate for obtaining good visualization of a peripheral stroke (volume approximately 49 ml). The simulations further showed that the displacement error had to be within 3-4 mm and the scaling error within 3-4% so as not to cause unacceptably large artefacts on the images.
Zolgharni
M
M
School of Medicine, Swansea University, Swansea, SA2 8PP, UK. massoud.zolgharni@gmail.com
Griffiths
H
H
Ledger
P D
PD
D002543:Cerebral Hemorrhage / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008280:Magnetics; D008953:Models, Anatomic; D020521:Stroke / Q000150:complications / Q000175:diagnosis; D014054:Tomography / Q000295:instrumentation* / Q000379:methods