Article
Locating steel needles in the human body using a SQUID magnetometer
Registro en:
MONTEIRO, E. Costa et al. Locating steel needles in the human body using a SQUID magnetometer. Phys. Med. Biol., London, v. 45, n. 2, p. 2389-2402, 2000.
0031-9155
Autor
Monteiro, E. Costa
Barbosa, C. Hall
Lima, E. Andrade
Ribeiro, P. Costa
Boechat, P. R. M.
Resumen
CNPq, FAPERJ, FINEP e PADCT A technique has been developed, based on magnetic field measurements, to localize,
in three dimensions, hypodermic and sewing needles lost in the human body. A theoretical model
for the magnetic field generated by needles has been elaborated and experimentally validated.
Using this model, the localization technique gives information about needle’s centre, orientation
and depth. The clinical measurements have been made using a SQUID system, with patients
being moved under the sensor with the aid of an X–Y bed. The magnetic field associated with
the remanent magnetization of the needle is acquired on-line and mapped over a plane. In all six
cases that occurred, the technique allowed surgical localization of the needles with ease and high
precision. This procedure can decrease the surgery time for extraction of foreign bodies by a large
factor, and also reduce the generally high odds of failure.