Quantification techniques to minimize the effects of native T1 variation and B1 inhomogeneity in dynamic contrast‐enhanced MRI of the breast at 3 T

The variation of the native T₁ (T₁₀) of different tissues and B₁ transmission‐field inhomogeneity at 3 T are major contributors of errors in the quantification of breast dynamic contrast‐enhanced MRI. To address these issues, we have introduced new enhancement indices derived from saturation‐recovery snapshot‐FLASH (SRSF) images. The stability of the new indices, i.e., the SRSF enhancement factor (EF_SRSF) and its simplified version (EF′_SRSF) with respect to differences in T₁₀ and B₁ inhomogeneity was compared against a typical index used in breast dynamic contrast‐enhanced MRI, i.e., the enhancement ratio (ER), by using computer simulations. Imaging experiments with Gd‐DTPA‐doped gel phantoms and a female volunteer were also performed. A lower error was observed in the new indices compared to enhancement ratio in the presence of typical T₁₀ variation and B₁ inhomogeneity. At changes of relaxation rate (ΔR₁) of 8 s^?1, the differences between a T₁₀ of 1266 and 566 ms are <1, 12, and 58%, respectively, for EF_SRSF, EF′_SRSF, and ER, whereas differences of 20, 8, and 51%, respectively, result from a 50% B₁ field reduction at the same ΔR₁. These quantification techniques may be a solution to minimize the effect of T₁₀ variation and B₁ inhomogeneity on dynamic contrast‐enhanced MRI of the breast at 3 T. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.