High resolution 3D MRI protocol optimization of corneal neovascularization in rabbits

Introduction Increasing interest in developing reliable and reproducible models to study angiogenesis has emerged due to recent advances in the treatment of eye disease with pathologic angiogenesis. Purpose The purpose of this study was to evaluate Corneal Neovascularization in rabbits using High Resolution Magnetic Resonance Imaging (HR-MRI). Materials and methods Animal experiments were performed with institutional Animal Care Committee approval. Corneal neovascularization was induced with a silk suture of the corneal stroma in 3 rabbits. A High-Resolution (HR) 84 × 84 × 600  μ m 3 MRI protocol was developed on a 1.5-T clinical system and applied in the left eyes, utilizing a small field of view surface coil. The area of corneal neovascularization was evaluated before and after the intravenous injection of different concentrations (0.2–0.02 mmol/kgr) of gadolinium-DTPA. Signal-to-Noise Ratios (SNR) and Contrast-to-Noise Ratios (CNR) amongst specific eye anatomical areas were calculated for each sequence. Results The neovascularized area was clearly visualized using MRI system. High concentration of gadolinium provides better delineation and visualization of the neovascularized area as compared with lower concentrations of the contrast agent. Even though the highest concentration of the contrast agent provides the best overall image quality, the neovascularized area presents high SNR even with the lowest concentration of the contrast agent. Conclusion MRI offers unique advantages over existing ocular imaging techniques, including the ability to image multiple layers without depth limitation and to provide multiple clinically relevant data in a single setting.