Article Text
Abstract
Introduction High resolution MRI has shown to be a promising technique to differentiate various pathologies that may be the cause of vascular stenosis and allow characterization of atherosclerotic plaque composition. Currently, there is no standard protocol for MR-imaging of intracranial atherosclerotic disease (ICAD), nor is there a gold standard phantom to compare MR-sequences. In addition, data generated by MRI is dependent on MR technique as well as scanner hardware. In this study, a small batch manufacturing technique is developed to create a plaque phantom that provides a platform for establishing a uniform imaging method for diagnosis of ICAD.
Materials and methods A stenotic basilar artery model was first prepared by infusing polyvinyl alcohol hydrogel (PVA) into the ABS core-shell mold. The ABS core-shell mold was 3D printed using the fused deposit manufacturing technique. Several freeze-thaw cycles were applied to cure the PVA hydrogel. Three stenotic vessel models were prepared and subjected to VasoCT scanning. Comparisons of the VasoCT reconstructions were performed to demonstrate the reproducibility of the abovementioned manufacturing technique. Two synthetic plaque components were attached to each stenotic vessel segment, namely a fibrous cap and a lipid core. A fibrous cap was constructed using a mixture of gadolinium chloride, agarose, carrageenan, sodium azide, water, and sodium chloride (T1 = 2859ms, T2 = 340ms). The lipid core was mimicked using a milk, sodium azide, and carrageenan mixture (T1 = 1099ms, T2 = 91ms). Each plaque component was prepared in a silicone mold with known shape and dimension. The plaque phantom was scanned using a Siemens 3T Trio or a 3T Philips MR scanner at 3 different sites and the results were compared.
Results The differences in radius between 3 stenotic vessels are presented in the Figure 1. Variations in signal intensity between the fibrous cap, lipid core and vessel wall were observed on the T2 images acquired from all 3 centers (figures not shown here).
Conclusion A plaque phantom composed of a stenotic vessel wall, a fibrous cap and a lipid core was successfully constructed for diagnosis of ICAD.
Disclosures J. Chueh: None. T. Turan: None. T. Brown: None. T. LeMatty: None. H. Mao: None. R. Swartz: None. E. Feldmann: None. J. Rappleye: None. K. van der Marel: None. M. Gounis: None.