A theoretical study on magnetic induction frequency dependence of phase shift in oedema and haematoma.
The spectroscopic distribution of induction phase shift as a function of the relative volume of oedema and haematoma in the brain, lung and muscle in the bulk of tissue was produced from the available tissue data and a simple mathematical model of electromagnetic induction in tissue. The results show that the phase shift is sensitive to the relative volume of oedema/haematoma at frequencies higher than approximately 10 MHz. The effect of oedema/haematoma on brain, lung and muscle tissues is tissue-type specific. Increasing the volume of tissue has the effect of lowering the frequency at which the phase shift becomes sensitive to the volume of oedema/haematoma. The results indicate that bulk induction measurement of the phase shift has the potential for becoming a simple means for non-contact detection of formation of oedema and haematoma in brain, lung and muscle tissues.
González
César A
CA
Department of Mechanical Engineering, University of California, Berkeley, CA 94720, USA. gonzalezantoni@hotmail.com
Rubinsky
Boris
B
D003198:Computer Simulation; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D004487:Edema / Q000175:diagnosis* / Q000503:physiopathology; D017097:Electric Impedance; D006406:Hematoma / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D008280:Magnetics; D008954:Models, Biological; D010992:Plethysmography, Impedance / Q000379:methods*