Conjunctival modifications induced by medical and surgical therapies in patients with glaucoma

Lowering intra-ocular pressure, either medically or surgically, is the proven strategy to control glaucoma, though profound changes to the ocular surface and conjunctiva are caused. Toxicity and allergy initiated by medical therapy induce modifications, which progressively worsen with the length of treatment and number of drugs. Conjunctival changes lead to symptoms of ocular surface disease, reduced quality of life, reduced therapeutic compliance and increased risk of surgical failure.Surgery modifies conjunctiva by inducing bleb formation in fistulizing techniques, and by activating secondary aqueous humour outflow pathways, such as trans-scleral routes, in both filtration and bleb-less approaches.The use of unpreserved medications, limitation of intra-operative conjunctival damage and development of bleb-less surgery are advisable.

440Highlights► Glaucoma medical therapy often induces squamous metaplasia, goblet cell loss and fibrosis. ► Both preservative and active compounds induce conjunctival modifications. ► Drug-induced conjunctival changes increase the risk of filtering surgery failure. ► Limitation of intra-surgical conjunctival manipulation is essential for the bleb survival. ► Bleb-less surgery enhances trans-scleral aqueous humour outflow.