fig 4.

Multiplanar radial fast field echo image, obtained during the third freezing cycle. Fluoroscopic MR imaging with ≤25 images per second was performed. The appearance of the inactive and active probe, including the ice formation, comes close to that of T1-weighted fast field echo, although the spatial resolution is reduced. Excellent ice:tissue contrast (mean signal intensity of the ice, 50.9 ± 21.6; mean signal intensity of the unfrozen brain, 474 ± 107). Interactive change from coronal to axial plane during scanning is shown (bottom row, left). Bright contrast of vasculature, which is orthogonal to the imaging plane (venous sinuses and orbital veins), can be seen. The hyperintense halo around the ice is present but is less well seen than that on T1-weighted fast field echo images