GLYCOSAMINOGLYCAN MATRIX IN CONJUNCTIVAL-SCLERAL SCARRING PREVENTION AFTER TRABECULECTOMY

The most frequent cause for glaucoma surgery failure apart from the progression of dystrophic changes in the eye’s drainage system is morphological changes in connective tissue structures that increase the risk of scarring at the operation site. Since currently available preventive measures, that are either based on medically affecting the wound healing process (e.g. metabolic antagonists) or method improvements, do not always give the intended result, there are also other directions of glaucoma research, one of which focuses on the application of drainage devices and systems. PURPOSE: to study the efficacy and safety of iGen drainage device in primary open-angle glaucoma surgery.

METHODS: The study group included 35 male and 51 female patients aged 55 to 79 years (mean age 65.9±9 years). All the patients of the study group (86 patients, 86 eyes) underwent an iGen drainage device implant. Among the patients, 37 (43.1%) had stage II glaucoma, 49 (56.9%) — stage III. Intraocular pressure (IOP) was moderately elevated in 52 patients (60.5%) and significantly elevated in 34 patients (39.5%). Mean IOP prior to the operation was 34.6±9.2 mm Hg with the minimum of24.7 mm Hg and the maximum of56.5 mm Hg.

RESULTS. One week follow-up showed mean IOP levels of 15.1±11.3 mm Hg. At day 30 of the post-surgical followup, IOP in the study group increased by 2–3 mm Hg and in average amounted to 17.8±6.4 mm Hg. Further observation showed no IOP increase, and at 12 months it equaled 18.8±2.3 mm Hg. Absolute success of iGen implantation was accomplished in 37 (42.9%) patients. Qualified success (IOP normalization without additional antihypertensive therapy + IOP normalization with additional antihypertensive therapy by 1.8 medications in average) was achieved in 71 (82.1%) patients. Complications frequency and characteristics depended on the initial clinical status and included ciliochoroidal detachment (10.4%), hyphema (10.4%), transient hypertension (1.2%).

CONCLUSION: The choice of explant drainage in repeated glaucoma surgery depends on predominant localization of cicatricial blockade of the outflow tracts created during previous surgeries. In cases when conjunctival-scleral adhesions served as the obvious cause of the surgery failure, iGen collagen drainage is preferable as having integral success rate of 82.1%.

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