Abstract 10754: Energy-Resolved Computed Tomography for Coronary Fibrin Imaging with New Gold Nanobeacons
Background: Intracoronary detection of coronary thrombus in patients presenting to the ED with chest pain with cardiac CT molecular imaging could preclude stress testing and accelerate decisions to intervene or discharge home. We hypothesize that spectral CT in conjunction with new targeted K-edge contrast agents will usher in this risk-stratify diagnostic advancement.
Objective: The objective of this study was to show the synergy between a new gold (Au) Nanobeacons and advances in statistical image reconstruction methods that together will improve coronary fibrin imaging by CT.
Methods and Results: Au NB (∼150 nm) were synthesized by concentrating Au nanoparticles (2-4nm) within a vascularly-constrained nanoparticle. AuNB (n=3) or control (n=3) NBs were bound to clots with a fibrin-specific monoclonal antibody (NIB5F3). The clots imaged in a soft-tissue mimicking polycarbonate phantom that included peripheral CaCl2 controls, providing attenuation effects similar to rib cage and spine. K-edge images were formed using conventional filtered back-projection (FBP) and a new statistical image reconstruction employing maximum-likelihood optimization and a Gaussian noise model with pre-determined noise estimation (ML-GV). Spectral CT imaging selectively detected the fibrin bound Au NBs, while routine CT failed to differentiate calcium deposits and the gold contrast (Fig left). K-edge imaging with FBP (right) eliminated the calcium signal and detected the targeted AuNB, but the new ML-GV image reconstruction (middle) technique produced superior signal to noise.
Conclusions: Parallel developments of new agents, e.g., AuNB, and energy-resolved spectral CT reconstruction innovations show the potential of intracoronary fibrin molecular imaging with CT.
- © 2011 by American Heart Association, Inc.