Yulin Ge MD, Presenter: Nothing to Disclose

Jens Jensen, Abstract Co-Author: Nothing to Disclose

Maltide Inglese, Abstract Co-Author: Nothing to Disclose

Anita Ramani, Abstract Co-Author: Nothing to Disclose

Joseph A Helpern PhD, Abstract Co-Author: Nothing to Disclose

Robert Ivin Grossman MD, Abstract Co-Author: Nothing to Disclose

There has been recent interest in exploring the role of iron in the pathogenesis and neuronal damage in MS by its oxidative damage. The analysis of in vivo iron concentration in MS brain provides a quantitative assessment and more specific information about the disrupted brain iron homeostatisis due to the disease. In this study, we have applied a newly developed iron contrast mechanism for iron quantitation based on magnetic field correlation (MFC), a measure that is particularly sensitive to microscopic field inhomogeneities, to assess iron accumulation in patients with MS.

12 patients with clinically definite relapsing-remitting MS and six age-matched normal controls were studied with a 3T MRI system (Siemens Medical Solution). After conventional MRI, MFC imaging was performed using a segmented asymmetric spin-echo echo planar imaging sequence (TR/TE: 2000/32ms; refocusing pulse shifts: 0ms, -3ms, -6ms, -9ms, -12ms; 1.8 mm slice thickness; matrix: 128x128; FOV: 230x230; EPI factor =43). MFC maps were generated from the images. Three regions of interest within the basal ganglia including thalamus, putamen, and globus pallidus were evaluated in all subjects.

Despite of normal appearance of deep gray matter regions on conventional MRI, the quantitative measurements of MFC showed significantly higher iron concentration in all deep gray matter nucleus in patients than those in normal controls, including thalamus (mean MFC: 202.9 vs 114.2; p = 0.002), putamen (mean MFC: 546.9 vs 287.8; p < 0.0001), and globus pallidus (mean MFC: 815.2 vs 634.9, p = 0.01). There is no correlation between the cerebral lesion load and the mean MFC taken from all three regions in these patients.

Our results indicate that the greater iron accumulation in the deep gray matter of MS patients is probably due to abnormal release of iron compound from the normal biding site of deep ferruginated neurons, which may be a process independent of white matter lesions, but can promote neuronal damage and neurodegeneration by free radicals.

Ge, Y, Jensen, J, Inglese, M, Ramani, A, Helpern, J, Grossman, R, Iron Accumulation in the Deep Gray Matter of Patients with Multiple Sclerosis Measured by Magnetic Field Correlation.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4412595.html