Estimation of brain iron in vivo by means of the interecho time dependence of image contrast

✍ Scribed by Frank Q. Ye; W. R. Wayne Martin; Peter S. Allen

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 627 KB
• Volume: 36
• Category: Article
• ISSN: 0740-3194
• DOI: 10.1002/mrm.1910360124

✦ Synopsis

Abstract

An imaging protocol for a quantitative estimation of disease‐induced variations in brain iron is proposed and then validated, first, on a phantom and second, on a group of 11 healthy volunteers. The relative estimate of brain iron is achieved from a rate difference image that measures the enhancement, δR~2app~, of the transverse relaxation rate of water protons brought about by the heterogeneous accumulation of iron in the glial cells. At 1.5 T, the phantom study demonstrates, over the range 0‐6 A/m, a linear dependence of δR~2app~ on the magnetization difference between micro‐spheres and a paramagnetic gel, with a sensitivity of ∼2 s^−1^ A^−1^ m. In the group of healthy volunteers (mean age 33 ± 7 years) devoid of disease‐related or appreciable age‐related accumulations of iron, the precision of δR~2app~ was still sufficient to distinguish the globus pallidus and the putamen from all of the other iron‐containing brain structures in a manner that was significant at the 99% confidence level.