Analysis of long-term results of collagen corneal cross-linking in patients with ectatic forms of corneal dystrophy
Corneal collagen cross-linking became a permanent part of complex treatment for patients with different forms of corneal ectasia. In periodical literature, there are anecdotal reports concerning long-term results of this corneal disease therapy method, which is an isolated variant of photodynamic therapy. Purpose. To carry out a retrospective study of corneal collagen cross-linking long-term results in various ectatic corneal diseases. Materials and methods. Results of corneal collagen cross-linking in patients with ectatic forms of corneal dystrophy 6 years after surgery were analyzed. The nosological structure of the study included a group of patients with primary keratoconus, pellucid marginal corneal degeneration, secondary ectasias. The group with primary keratoconus includes 30 patients (31 eyes), that with pellucid marginal degeneration 10 patients (10 eyes), that with secondary ectasias – 10 patients (10 eyes). Data of the diagnostic examination before surgery, intermediate data of the dynamic follow-up during 6 years of observation were used for the analysis. Corneal collagen cross-linking was performed in the first or second year of follow-up, followed by monitoring of changes in the state of the cornea after corneal collagen cross-linking for 4-5 years. Results. A statistically significant increase in visual acuity was observed after the corneal collagen cross-linking in patients with primary and secondary ectasias. In patients diagnosed with pellucid marginal degeneration, there was no statistically significant increase of visual function. A decrease in the corneal asymmetry index was revealed in all groups and confirmed by statistical analysis.