Figure 1
T2* weighted spiral imaging of the right common carotid artery in-vivo, pre (A) and 36 hours post USPIO infusion (B) showing signal loss in areas of USPIO uptake (yellow arrows). (The 2D T2* weighted spiral acquisition used a spectral-spatial excitation pulse, with a TE of 5.6 ms. The multi-shot spiral sequence involved the acquisition of 22 spiral interleafs each of 4096 data points resulting in an effective in-plane pixel size of 0.42 × 0.42 mm, two signal averages were performed and a quadruple inversion preparation was utilised to null the signal from blood pre – and post USPIO. Slices were acquired sequentially with a 3 mm thickness and no inter-slice gap.). Pre (C) and 36 hours post USPIO infusion (F) T2* weighted spiral imaging in-vivo revealing signal drop in the wall of the aneurysm post-USPIO (yellow arrows) likely corresponding to regions with a high inflammatory burden. Corresponding ex-vivo imaging in a dedicated micro-coil with T2 map (D) showing regions with very short T2 species (yellow arrow) corresponding with area of USPIO uptake. Ex-vivo inversion recovery on-resonance water suppression (IRON) imaging [9] (E) with off-resonant spins showing positive contrast due to dephasing of spins adjacent to USPIO uptake. H&E section (x40) co-registered with ex-vivo imaging (using distance from the bifurcation). Area of intraplaque haemorrhage within a small necrotic lipid core can be seen (red arrow), adjacent to the USPIO uptake seen in the ex-vivo imaging. Structural MR Imaging in the same patient reveals anatomy of the co-existing abdominal aortic aneurysm (H&J).