Magnetic resonance fingerprinting is an efficient, new approach for quantitative imaging with MR. We aimed to extend this technique to cases with B1. + inhomogeneities within the imaging volume.Previous approaches have used abrupt changes in flip angles to estimate the B1. + field simultaneously with T1 and T2, using a Cartesian approach in a small-animal scanner at 4.7. T. Here, we evaluated whether a similar approach would be suitable for imaging human brains using spiral readouts with a 7. T scanner.We found that our modified scheme could significantly reduce the adverse effects of B1. + inhomogeneities even in extreme cases, reducing both the bias and the variance in T2 estimations by an order of magnitude when compared to literature methods. Acquisitions used less than 1.5. W/kg SAR and could be performed in 12. s per slice.In conclusion, our approach can be used to perform quantitative imaging of the brain at 7. T in a short time, simultaneously estimating the B1. + profile.
- MR fingerprinting
ASJC Scopus subject areas
- Biomedical Engineering
- Radiology Nuclear Medicine and imaging