Juliane Budde

Ultra-high field MRI systems of 7 T and above have been emerging within the last years with the goal of taking advantage of the expected increase in signal-to-noise ratio (SNR) and possibly unique contrast mechanisms. These developments are intricately tied with a number of specific problems not encountered at conventional fields. These effects, however, also open up new possibilities for novel and improved image contrast, permitting better visualization of internal structures as well as the venous vessel network with susceptibility weighted imaging (SWI).

One of the major goals in functional imaging research is to determine and optimized the spatial specificity of the BOLD response. Combining fMRI with high resolution anatomical information can help to localize and eliminate venous signal contributions (2,3). This is further enhanced by the higher SNR and predicted increase in BOLD signal expected at higher magnetic field strength, allowing better spatial resolution, as well as by the improved spatial specificity that is expected especially for spin-echo fMRI. Furthermore, phase imaging, which can be capable of detecting structural variations within the cortex, can help to distinguish different parts of the cortex according to its morphology improving between-subject comparison or can also aid to gain layer-specific activation. Thus, human functional brain imaging in normal subjects as well as in patients can benefit in terms of specificity and sensitivity.