Features of the reparative process after antiglaucoma surgery

Abstract

Excessive fibrosis and scarring of newly created aqueous humor outflow pathways, mainly at the level of the intrascleral canal and filtering bleb, is a significant disadvantage of the so-called bleb-dependent antiglaucoma surgery. Taking into account the fact that aqueous humor, which flows evenly through the non-healing fistula under the hermetically sutured conjunctiva, is the forming substrate for the newly created outflow pathways, its composition also plays an important role in the body's response to surgical trauma. A large number of publications reliably demonstrate an increase in the concentration of various biologically active molecules in the aqueous humor of the anterior chamber of glaucoma patients. These are transforming growth factor β (TGF-β), vascular endothelial growth factor (VEGF), tumor necrosis factor-α (TNF-α), interleukins IL-6 and IL-8, etc., which concentration in cases of unsuccessful outcome of trabeculectomy was significantly increased compared to patients who underwent successful surgeries. In addition, it has been established that an imbalance of various matrix metalloproteinase pools, fibroblast activation, wound infiltration by neutrophils and macrophages, which in turn express a significant amount of pro-inflammatory cytokines and growth factors, contribute to the prolongation of inflammation and fibrosis. An important condition for the removal of aqueous humor from the filtering bleb area is the postoperative activation of conjunctival lymphatic angiogenesis, which suppression may be associated with prolonged inflammation or the active use of cytostatics. This literature review presents the complexities of the pathophysiological mechanisms of postoperative healing and the formation of newly created aqueous humor outflow pathways after antiglaucoma operations. At the same time, the question remains open about the effect of initial changes not only on the tissues of the ocular surface, but also in the aqueous humor of the anterior chamber, as well as the general condition of patients on the outcome of the operation.The purpose of this review is to present modern literature data on the pathophysiological mechanisms of the wound healing process and the features of postoperative healing regulation after antiglaucoma surgery.