Article

Sensitivity of T2-weighted FSE sequences towards physiological iron depositions in normal brains at 1.5 and 3.0 T.

Department of Clinical Radiology, University of Muenster, Albert-Schweitzer-Strasse 33, 48149 Münster, Germany.
European Radiology (impact factor: 3.22). 07/2004; 14(6):1000-4. DOI:10.1007/s00330-004-2241-4 pp.1000-4
Source: PubMed

ABSTRACT To evaluate the sensitivity of T2-weighted fast spin-echo (FSE) sequences to physiological iron depositions in normal brains at MR imaging field strengths of 1.5 and 3.0 T. T2-weighted FSE sequences acquired at 1.5 and 3.0 T clinical imaging systems (Gyroscan Intera, Philips Medical Systems, Best, The Netherlands) were compared by means of MRI in phantoms ( n=6) and healthy volunteers ( n=10). Contrast-to-noise ratios (CNRs) of tubes doped with iron oxides at different concentrations and of brain areas with physiological iron depositions (nucleus ruber, substantia nigra, globus pallidus) were calculated for either field strength. Apparent susceptibility effects of iron-containing brain structures were qualitatively analyzed by comparing the degree of visible hypointensity by a score system at either field strength. The mean CNR of iron oxide tubes and iron-containing brain areas was significantly decreased at 3.0 T. Qualitative analysis confirmed these measurements. Detection and diagnosis of brain disorders with altered iron content such as neurodegenerative parkinsonian disorders (NPD) or intracerebral hemorrhage should benefit from the increased sensitivity of T2-weighted FSE sequences to susceptibility effects at 3.0 T.

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Keywords

Apparent susceptibility effects
 
brain disorders
 
field strength
 
globus pallidus
 
Gyroscan Intera
 
iron content
 
iron oxide tubes
 
iron oxides
 
iron-containing brain areas
 
iron-containing brain structures
 
MR imaging field strengths
 
normal brains
 
Philips Medical Systems
 
physiological iron depositions
 
T clinical imaging systems
 
T. Qualitative analysis
 
T. T2-weighted FSE sequences
 
T2-weighted fast spin-echo
 
T2-weighted FSE sequences
 
visible hypointensity