Abstract
Purpose: :
To study funduscopic, angiographic and morphologic ultrastructural effects of an experimental glaucoma model in minipigs Göttingen.
Methods: :
Funduscopic and angiographic characteristics were studied before the experimental period in both eyes of 8 minipigs. By cauterization of dorsal and ventral episcleral veins of the left eyes, we induced chronic elevation of IOP. At the end of the experimental period (9 months), funduscopic, and angiographic effects of chronic elevation in IOP in left eyes and in control right eyes were compared. Afterwards, aqueous vessels (Schlemm's canal equivalent) and trabecular meshwork specimens of dorsal quadrant were analyzed morphologically by electron microscopy.
Results: :
In 75% of the experimental left eyes, the optic disk showed a peripheral arteriolar incurvation and retinal nerve fiber defects such as optic disk changes in primary open angle glaucoma (POAG) in humans. There is an increase in the amount of fibrillar material in the subendothelial region, less optically empty spaces and significant increase in cell organelles (rER) in all experimental left eyes studied.
Conclusions: :
In this experimental glaucoma model there are similar optic disk changes as POAG in humans. Ultrastructural changes in the subendothelial region of the aqueous vessels in this model indicate that chronic elevation in IOP may induce ultrastructural changes in the cribiform region.
Keywords: intraocular pressure • microscopy: electron microscopy • outflow: trabecular meshwork