Revising the Question of Keratoconus Classification

Abstract

Aim: To develop a new surgical keratectasia classification. Materials and methods:We did analysis of existing variants of classification of keratectasia, discussion of newly appeared classifications. We discussed advantages and disadvantages of the presented information. We also discussed the decision of a question on creation of the optimum approach to surgical treatment of patients depending on a kind and a stage of keratectasia.Results: Keratectasias were classified according to the presence of the ectatic process progression (progressive and stable); type of ectasia (primary and secondary); ectasia symmetry (symmetrical and nonsymmetrical); stages (0, I, II, III and IV). The following are recommended for each stage: Subclinical stage 0: Observation and check-up every 6 months; stage I: Ultraviolet (UV) cross-linking; stage II: Intracorneal ring segments (ICRS) implantation, UV cross-linking only if residual ametropia correction by photorefractive keratectomy (PRK) or toric intraocular lenses (TIOL) implantation is planned; stage III: Deep anterior lamellar keratoplasty (DALK); stage IV: penetrating keratoplasty (PK). Conclusion:The presented keratectasia classification is based on modern diagnostic methods; it allows to determine the tactic of surgical treatment, depending on the type and stage of the pathological process.Clinical significance: Our classification helps doctors to easily put the stage of keratoconus process and decide on the following surgical treatment.