H. Oellinger et al., EFFECTS BY PARAMAGNETIC AND DIAMAGNETIC MATERIALS IN A 1.5-TESLA HIGHFIELD MAGNETIC-RESONANCE-IMAGING SYSTEM (MRI), Biomedizinische Technik, 43(10), 1998, pp. 281-286
This article shows the results of an experimental investigation of the
interference by paramagnetic and diamagnetic materials on imaging in
a closed 1.5 Tesla high field magnetic resonance imaging system (MRI).
For different types of sequences (SE, GE, EPI) the effects of metal a
nd non-metal profiles in producing artefacts were investigated. A phan
tom (plastic trunk) filled with Gd-Mn-solution was used for representa
tion of the artefacts. The materials analysed were placed parallel to
the phantom at predetermined distances. The images were obtained in tr
ansverse and sagittal planes and analysed with respect to the resultin
g artefacts. The results show that aluminum and polymer profiles produ
ce the weakest artefacts, even when the material is positioned close t
o the phantom. A comparison of the sequence types shows that the SE-se
quence has a low sensitivity to artefacts, despite the great profile v
ariation in size and shape. The SE-sequence accordingly showed a highe
r imaging stability as compared with the GE- and EPI-sequences. Steel
and copper produced the strongest artefacts. The examination was begun
after an intensive study of the literature (Internet, Medline, Medite
c). So far have been few publications on this subject.