[The long-term follow up after trabeculectomy]

To estimate the efficacy of trabeculectomy for primary open angle glaucoma.

Since 1990 to 2000 we observed 91 eyes of 79 patients (53 women and 26 men) aged 39-86. The results of performed surgery were valued directly after the trabeculectomy and in period of over 8 years. We carried out the examinations of visual acuity, intraocular pressure, visual field, state of optic nerve head, type of bleb following trabeculectomy and the necessity of applying additional topical treatment. The trabeculectomies were performed in a typical way. Some surgeons made a square or triangular superficial scleral flap based at the limbus, measuring from 2.5 x 3.0 to 4 x 4 mm or 3 x 3 mm. The deep block of scleral tissue with trabeculum (from 0.5 x 1.0 to 2.5 x 3.0 mm) was excised, the superficial cauterisation and the peripheral iridectomy were performed in every case. The scleral flap and conjunctiva were sutured with 10/0 Ethilon, 8/0 Vicryl or 6/0 Mersilk.

The patients were divided into 3 groups depending on observation period: I--up to 4 years, II--from 5 to 8 years, III--over 8 years. We confirmed the normalisation of IOP in 80%, 73%, 90% and the successful control of visual field (no progress) in 82%, 77%, 70% of adequate groups. In the first and second group 45-50% of patients could resist from topical treatment, but after 8 years as many as 80% required additional pharmacological treatment.

The trabeculectomy is the effective surgery in most patients with open angle glaucoma. The effectiveness of trabeculectomy can be controlled by the size of extracted deep scleral flap with trabeculum. For the stability of visual field it is necessary to keep the intraocular pressure at 13-18 mm Hg level.