Abstract #0018

Comparison of Template and Individual-Based Gradient Compensated EPI in Regions Affected by Local Susceptibility-Induced Signal Loss

Jochen Rick¹, Oliver Speck², Olaf Dssel³, Jrgen Hennig¹, Maxim Zaitsev¹

¹Dept. of Diagnostic Radiology, Medical Physics, University Hospital Freiburg, Freiburg, Germany; ²Biomedical Magnetic Resonance, Otto-von-Guericke University, Magdeburg, Germany; ³Institute of Biomedical Engineering, University Karlsruhe (TH), Karlsruhe, Germany

Anatomy-related susceptibility gradients in the human head lead to artefacts in echo planar imaging (EPI). The use of a slice-dependent common gradient compensation template improves fMRI sensitivity in areas affected by strong susceptibility gradients. This study evaluates the concept through a comparison between four groups (no compensation, common template (member), common template (not member), individual). In general the signal improvement of the three compensated cases is about 35%. No significant variations are present between these cases. Thus, it seems possible to use this method for functional experiments without repeating the calibration individually, thus saving adjustment and calculation time.