[Physiology of aqueous humor outflow resistance: its relation to giant vacuoles]

About 2% of the French population over the age of 40 suffers from open angle glaucoma, a disorder for which ocular hypertension is the main risk factor. Improving our understanding of primary open-angle glaucoma physiopathology has been an area of intense research for nearly a century. The main aqueous outflow system in the human eye includes the trabecular meshwork, Schlemm's canal, aqueous veins, and the episcleral veins. Schlemm's canal is bordered by endothelium cells, many of which contain giant vacuoles, structures that are sensitive to intraocular pressure and that therefore can act as markers of active outflow. Giant vacuoles are most often found near collector channels in normal eyes, probably in areas of low downstream pressure. In the glaucoma eye, determining where giant vacuoles form could help localize the site of pathological outflow resistance.