An AC magnetizing field biosusceptometer using a SQUID based sensor with additional compensation module

Author

Della Penna, S. ; Gratta, C. Del ; Cianflone, F. ; Erné, S.N. ; Granata, C. ; Pentiricci, A. ; Pizzella, V. ; Russo, M. ; Romani, G.L.

Author_Institution

Dept. of Clinical Sci. & Bioimaging, "G. D\´\´Annunzio" Univ., Chieti, Italy

Volume

13

Issue

2

fYear

2003

fDate

6/1/2003 12:00:00 AM

Firstpage

348

Lastpage

351

Abstract

We present a new SQUID based susceptometer for liver iron concentration (LIC) assessment. The instrument is operated with an inhomogeneous AC magnetizing field. The susceptometer is based on 7 channels, each consisting of a sensing unit and of an additional unit for the compensation of the applied field residual and its variation. Each unit is a second order gradiometer and is coupled to a dc SQUID with a parallel washer configuration. The compensation module output is digitally processed and coupled to the sensing gradiometer by means of an additional feedback path. The estimation of LIC is based on a numerical model of the subject´s torso obtained from the segmentation of ultrasound images.

Keywords

SQUID magnetometers; biomagnetism; biomedical electronics; biomedical measurement; biomedical ultrasonics; image segmentation; liver; medical image processing; SQUID based sensor; SQUID based susceptometer; alternating current magnetizing field biosusceptometer; applied field residual; biomagnetic liver biopsy; compensation module; diagnosis; feedback path; haematological diseases; inhomogeneous AC magnetizing field; liver Fe concentration assessment; magnetic susceptibility; numerical model; parallel washer configuration; second order gradiometer; segmentation; sensing gradiometer; sensing unit; subject´s torso; ultrasound images; Biosensors; Image segmentation; Instruments; Iron; Liver; Magnetic sensors; Numerical models; Output feedback; SQUIDs; Torso;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/TASC.2003.813733

Filename

1211613