Purpose: Small vessel disease as seen in hypertension and diabetes can be associated with cerebral
microbleeds. These might be indicative of higher risk for future intracerebral hemorrhage.
The implementation of susceptibility weighted imaging (SWI) in high field MRI systems
(7 Tesla) makes use of enhanced tissue signal and sensitivity to susceptibility differences.
Our goal is to present initial results visualizing cerebral hemosiderin deposits and
surrounding microangiopathy with high-field MRI.
Materials and Methods: Five healthy volunteers and eight patients with known microbleeds and/or microangiopathy
were examined with a whole-body 7 Tesla scanner (Magnetom 7T, Siemens), and an eight-channel
transmit-receive head coil (Rapid Biomedical, Germany). Optimized SWI, T2*, and FLAIR
sequences at 7 Tesla were compared to standard 1.5 Tesla images regarding depiction
of hemosiderin deposits (T2*, SWI) and white matter lesions (FLAIR).
Results: All known pathologies (from 1.5T) were revealed at 7 Tesla. 7T gradient echo sequences
(SWI and T2*) revealed especially small microbleeds more clearly in 6/8 patients.
7T-SWI revealed hemosiderin deposits more distinctively than 7T-T2* in 4/8 patients.
7T FLAIR sharply visualized white matter lesions equivalent to 1.5T. Compared to 1.5T,
image resolutions were higher at 7T (max. resolution used for SWI: 0.22×0.22×1.5mm3).
Conclusion: 7T MRI can demonstrate signs of cerebral small vessel pathology. Improved detection
of microbleeds at 7T might in the future have significant impact on the therapy of
patients showing cerebral small vessel disease by providing additional criteria to
optimize antithrombotic treatment.
