TY - JOUR T1 - T2* Mapping with Background Gradient Correction Using Different Excitation Pulse Shapes JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. SP - E65 LP - E68 DO - 10.3174/ajnr.A3021 VL - 34 IS - 6 AU - N.M. Hirsch AU - C. Preibisch Y1 - 2013/06/01 UR - http://www.ajnr.org/content/34/6/E65.abstract N2 - SUMMARY: Background gradients induced by magnetic susceptibility variations near air-filled cavities in the brain cause signal-intensity loss in gradient-echo images and shorten T2* considerably. With a correction method in which the exponential decay is restored with section-profile-dependent correction factors, parts of the signal intensity can be recovered. While uncorrected T2* values drop by 20% at a gradient strength of 75 μT/m, with correction and exponential excitation pulses, this boundary is pushed to 220 μT/m. ER -