The Study Of USPIO Enhanced MRI To Detect Atherosclerotic Plaques In The Hypercholesterolemic Rabbit

Objective USPIO is an MRI contrast agent, which accumulates in macrophages and induces magnetic susceptibility. We evaluated the ability of USPIO enhanced MRI to quantify unstable atherosclerotic plaque of hypercholesterolemia rabbits. Methods Atherosclerosis model with unstable plaque had been established by double balloon aorta injury in hypercholesterolemia rabbit. After establish the model successfully, the rabbits were examined by MRI and MRI with USPIO for 6 days. To define the RIO of vessel wall and detect the SNR, we draw the curve chart follow the change of SNR for one week and find the optimal time of reinforcement. The atherosclerotic plaque components were observe by pathological study and detect USPIOs were swallow by transmission electronic microscopy. Results Traverse pathology showed that the second-injury group has more unstable plaque than first-injury group(P<0.01). Atherosclerotic plaque components of MRI images correlated with the result of pathology. Luminal irregularities are visible in the injured aorta four days after injection of USPIO in the images of MIP. The signal intensity of injured arterial wall was gradually decreasing and the lowest on the fourth day. The percentage reduction in luminal area in the injured aorta strongly correlated with the Perl-positive (y=172.1x+0.6; r=0.78; P<0.05). Conclusions Atherosclerosis model were successfully established by twice balloon injury in hypercholesterolemic rabbits. MRI images correlated with the result of pathology in diagnosis of atherosclerosis plaque. USPIO enhanced MRI to quantify atherosclerotic plaque of hypercholesterolemic rabbits.