Long-term results of surgery in childhood glaucoma

The aim of this study is to assess the functional results and morphological parameters in children surgically treated for glaucoma.

Data from 43 patients and 68 eyes who were operated in our department between 1990 and 2002 were collected. This retrospective trial included primary congenital glaucoma (n=36), and secondary glaucoma (n=7) in Rieger-Axenfeld syndrome and Sturge Weber syndrome. Intraocular pressure (IOP), axial length of the eyeball, visual acuity, refractive errors and orthoptic status were analysed.

The age of patients at the first surgery was 6.0 +/- 5.3 months (range 0.7 to 28.0 months). The mean period of follow-up was 57.3 +/- 36.8 months (6.0-161.0). The mean number of surgical procedures performed on one eye was 2.5 +/- 2.4 procedures (1-11). The mean IOP before the first surgery was 31.0 +/- 7.9 mmHg (17.5-52.0), and was 15.0 +/- 3.9 mmHg (7.0-28.0) at the last visit. 49 eyes (72.1%) did not need any further medical treatment after the last surgical procedure. The IOP was 18 mmHg or lower without medication in 29 eyes (42.6%) after just one surgical procedure (21 trabeculotomy, 8 combined trabeculotomy/trabeculectomy with or without mitomycin-C). At the first examination, the mean axial length of the eyeball was 22.6 +/- 1.8 mm (the mean normal value at this age is 20.3 +/- 0.7 mm), and was 24.4 +/- 2.0 mm at the last visit (the mean normal value at this age is 22.2 +/- 0.6 mm). The best corrected visual acuity at the last visit was 0.25 +/- 4.6 lines; the normal range of visual acuity at this age is from 0.4 +/- 4.0 lines to 0.8 +/- 3.0 lines. Visual acuity was 0.32 or more in 53.0% of the eyes. Visual acuity was lower than 0.1 in only 15.2% of the eyes. Myopia was present in 57.4% of the eyes with a mean spherical equivalent of -6.1 +/-3.9 dioptres. 15 patients (34.9%) developed strabismus. 22 patients (51.2%) were treated with part-time occlusion. Binocular function as assessed with the Lang-1 test was positive in 17 of 30 patients (56.7%).

Although a good long-term IOP-control can often be achieved in childhood glaucoma, the visual acuity remains below the normal range in most cases despite close orthoptic follow-up.