Heparin-surface-modified PMMA intraocular lenses in children in early and long-term follow-up

Introduction
To compare anatomical and functional state of eyeballs after congenital cataract extraction and heparin-surface-modified PMMA (HSM-PMMA) or PMMA implanted lenses and to conclude, which type of implants is more advantageous in young patients.

Material and methods
42 eyes of 30 children at the age of 3 – 16 years with congenital or developmental cataract after extraction and IOL implantation: I group – HSM-PMMA lenses in 24 eyes, and PMMA lenses in 18 eyes – II group. Mean age in the I group was 6 years and in the II group 8 years, p = 0,07. The presence of cellular and pigment deposits on the IOL surface as a sign of postoperative inflammation was examined by slit-lamp within 1 month after surgery. We have compared the results of visual acuity (V/A), corneal endothelium cell density and posterior capsule state. The examinations were done in the short-term follow-up mean 14,1 months (4-24 months) in the I group and mean 32,1 months (16-48 months) in the II group. In the long-term follow-up mean 38 months (30-44 months) in the I group, and mean 56,1 months (40-72 months) in the II group.

Results
Within first month after operation cellular and pigment deposits on the IOL surface were seen more often in the II group, p = 0,03. Best corrected V/A was comparable in both groups in the short-term and the long-term follow-up. At last visit, mean value of V/A was 0,54 (I group) and 0,42 (II group), p = 0,37. There was no significant difference between central corneal endothelial cell density in both groups: before (2893 ± 261/mm2 and 2821 ± 217/mm2, p = 0,143) and after operation (2371 ± 202/mm2 and 2361 ± 299/mm2, p = 0,428). In the short-term follow-up, but not longer than within first 12 months after surgery the frequency of clinically significant posterior capsule opacification (PCO) was less in the HSM-PMMA group (8%), than in the PMMA group (33%), p = 0,006. In the long-term follow-up there was no statistically significant difference in PCO appearance between these groups (44% and 50%, p = 0,27).

Conclusions
Heparin-surface-modified intraocular lenses reduced postoperative inflammation and delayed the incidence of PCO in children. Heparin- surface-modified intraocular lenses are more advantageous, than PMMA lenses in young patients.