ABSTRACT. Purpose: To evaluate the outcome, long-term results and contributing prognostic factors of trabeculectomy in terms of intraocular pressure (IOP) and to compare the results in primary open-angle glaucoma (POAG) and exfoliation glaucoma (EG).Methods: This study involved retrospective evaluation of 138 consecutive patients (138 eyes) with either POAG or EG. All patients had undergone primary trabeculectomy performed by the same surgeon between November 1994 and August 1996. Only one eye per patient was included. Operations performed with the use of antimetabolites were excluded. All patients were aged over 40 years and were white. Follow-up for all subjects lasted at least 2 years. Successful control of IOP was defined as achieving IOP Յ 21 mmHg without medication (complete success) or with a single topical medication (qualified success). Success rates were determined using the Kaplan-Meier survival curve, and risk factors were analysed with proportional hazards regression. Results: According to the Kaplan-Meier survival curve, success rates (complete or qualified) were 82% at 1 year, 70% at 2 years, 64% at 3 years and 52% at 4 years. A total of 63% were complete successes at 1 year, 54% at 2 years, 45% at 3 years and 40% at 4 years. Complete success rates were significantly better in the POAG group than in the EG group. Proportional hazards regression analysis showed that the presence of EG and early postoperative IOP Ͼ 30 mmHg decreased the possibility of complete success, while a cataract operation performed during follow-up improved it. Conclusion: The IOP-reducing effect of trabeculectomy decreases gradually. After 4 years, 52% of operated eyes had IOP Յ 21 mmHg with or without a single topical medication. Diagnosis of EG implied a worse long-term outcome for trabeculectomy in terms of IOP.

ABSTRACT.Purpose: To evaluate retrospectively risk indicators for cataract surgery and the effect of phacoemulsification on intraocular pressure (IOP) control in eyes that have undergone trabeculectomy. Methods: We undertook a retrospective analysis of 138 eyes with primary openangle glaucoma (POAG) or exfoliation glaucoma (EG) in 138 consecutive patients over the age of 40 years undergoing trabeculectomy with no antimetabolites performed by one surgeon. Of the 48 eyes (35%) undergoing a cataract operation during the follow-up period of 2-5 years, 46 were included in this analysis. Their IOP, glaucoma medication and best corrected visual acuity (BCVA) before cataract surgery and at the last follow-up were compared. Risk indicators for cataract surgery were analysed. Results: Cataract operations were performed 5.1-58.1 months (median 14.4 months) after trabeculectomy. The mean length of follow-up after cataract surgery was 25.3 months (SD 12.9, median 24.8 months). Before cataract surgery, the mean IOP was 16.2 mmHg (SD 4.9) and the mean number of topical antiglaucoma medicines 0.8 (SD 1.0). At the most recent visit, mean IOP was 17.3 mmHg (SD 6.4) (p = 0.35), and the mean number of medicines was 1.3 (SD 1.1) (p = 0.0007). Of the 22 eyes in which treatment had been categorized as completely successful (IOP £ 21 mmHg without other therapy) before cataract surgery, 13 (59%) had remained so. The number of failures (IOP > 21 mmHg, or more than one medication needed or further surgery performed) increased from 14 (30%) before surgery to 28 (61%) afterwards. The proportion of failures in the cataract surgery group was twice that in the no cataract surgery group (61% versus 31%). In a proportional hazards regression, only age (73.9 years [SD 9.4] and 68.1 years [SD 9.8] in patients with and without cataract surgery, respectively) proved to be a significant (p = 0.001) indicator for surgery. Conclusion:The results of this retrospective study on consecutive clinical cases of trabeculectomy indicate that cataract progression after trabeculectomy is mainly an age-related process. In more than half the eyes with good preoperative IOP control, this good control was maintained after cataract surgery. On the other hand, in some eyes cataract surgery may compromise IOP control even when surgery avoids the area of the bleb.

Progression of VF defects and development of visual impairment due to glaucoma was fairly common despite trabeculectomy. Both were associated with severity of initial VF defect. In this series, no significant correlation appeared between defect progression and the last IOP, but association between stability of VF and the amount of IOP reduction after surgery indicate that a lower target IOP level particularly in eyes with initially severe VF defect would, however, be needed.

Early postoperative complications after trabeculectomy were common, but the only significant predictor of failure was increased intraocular pressure at the end of the 1st postoperative month.