Dynamic contrast-enhanced MRI of ocular biotransport in normal and hypertensive eyes

This study aims to employ in vivo dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to evaluate the ocular transport following an induction of ocular hypertension in a rat model of chronic glaucoma. Upon systemic administration of Gd-DTPA solution, T1-weighted signal increase was observed in the vitreous body of the glaucomatous eye but not the control eye. This increase occurred earlier in the anterior vitreous body than the preretinal vitreous. Further, there was an earlier Gd-DTPA transport into the anterior chamber in the majority of glaucomatous eyes. Our DCE-MRI findings revealed the leakage of Gd-DTPA at the aqueous-vitreous interface, which was likely resulted from increased permeability of blood-aqueous or aqueous-vitreous barrier. These may explain the sources of changing biochemical compositions in the chamber components, which may implicate the neurodegenerative processes in the glaucomatous visual components.