Limits of 8-Tesla magnetic resonance imaging spatial resolution of the deoxygenated cerebral microvasculature.

PURPOSE

To quantify the minimum magnetic resonance imaging (MRI) spatial resolution of the visible deoxygenated microscopic vessels of the human brain at 8 T.

MATERIALS AND METHODS

This study compared 8-T gradient echo (GE) images of a human cadaver brain having an in-plane resolution of 195 x 195 microm to corresponding digital photographs of 205 cryomicrotome sections of the same cadaver brain, along with summed images of 25 contiguous cryomicrotome sections. One-millimeter-thick GE images of a 1-cm-thick unfixed whole coronal brain section were acquired using techniques similar to those commonly utilized for 8-T human imaging in vivo.

RESULTS

There was excellent MR visualization of the deoxygenated microscopic vessels within the brain down to a resolution of approximately 100 microm.

CONCLUSION

By taking advantage of magnetic susceptibility-based blood oxygenation level-dependent (BOLD) contrast, deoxygenated microscopic blood vessels smaller than the pixel dimensions used for imaging can be visualized using a whole-body 8-T MRI system.