Chronic glaucoma filtering surgery

This eye disease progressively destroys the optic nerve which results in an insidious deterioration of the visual field and exposes the ultimate stage to loss of vision. The causes of glaucoma are numerous and the most common is the increase in eye pressure which is linked to the dysfunction of the filter (the trabeculum) allowing the evacuation of the liquid circulating in the eye (the aqueous humor). Surgery involves excising a portion of the trabeculum in part or in whole to facilitate the evacuation of aqueous humor out of the eye and therefore to lower eye pressure. There are two types of filtering procedures that create a valve with the tissues of the eye: - trabeculectomy, which involves excising a small part of the trabecular filter, therefore opening the eye during the operation. - the deep non-perforating sclerectomy which involves excising only the external part of the filter without opening the eye.