Figure 7.

Visualization of vascular structures using cryogenically cooled RF coil technology to provide high resolution time-of-flight (TOF)-MRA and spin dephasing following intravascular iron oxide contrast agent. (A) High-resolution 3D TOF-MRA (axial and horizontal view) of the intracranial and extracranial vasculature of a 2-month-old wild type control mouse using a gradient echo sequence with flow compensation acquired at 9.4 T using the CryoProbe (TR = 30 ms, TE = 5.9 ms, FOV = (30 × 15 × 15) mm³, 512 × 256 × 256, isotropic resolution = 59 μm³. From Supplementary Data in Waiczies et al. (2012), by permission of Public Library of Science. (B) Contrast-enhanced cerebral MRA of a 24-month-old wt mouse and an age-matched arcAβ mouse before and after administration of a superparamagnetic iron oxide contrast agent. Images were acquired using a 3D FLASH sequence [TR = 150 ms, TE = 2.9 ms, FA = 20°, FOV = (15 × 12 × 2.2) mm³, spatial resolution of (60 × 60 × 61) mm³]. Difference images were obtained by subtraction of postcontrast image from precontrast image. The arrows point to focal hypointense areas that are present before administration of the contrast agent. Scale bar: 1 mm. From Klohs et al. (2012), by permission of Elsevier.