Heterogenicity of Congenital Cataract and Its Influence on Pseudophakic Eye Refraction Changes. Summary of the Doctoral Thesis

Abstract

Congenital cataract is one of the most serious paediatric ophthalmological diseases causing potential weaksightedness. It belongs to rare diseases, characterized by its distribution, lesser than 5 cases per 10 000 population. In difference to cataract in adults, the children eyesight system is only developing, consequently, cataract or severity of lens opacity, treatment options and complications interefere or work simultaneously with the eye optic system and children vision development. The earlier is cataract onset time, the denser, wider and more central will be the morphological eye lens opacity, the more serious danger it will be to the eye and children vision development. Although Latvia does not belong to those countries in the world where children become blind due to unoperated congenital cataracts, and the cataract surgical correction in the last twenty years has rapidly developed both in the world, and in Latvia, congenital cataract treatment is still a challange both for paediatric ophthalmologists, catarct surgeons, vision pedagogues, optometricians, paediatricians, neonatologists, medical genetics specialists, and children’ parents. Weaksightedness due to congenital cataract and prevention of blindness is the priority of the World Health Organization and the joint project of the International Blindness Prevention Agency “VISION 2020 – Right to See”. The aim of the study was to prove heterogenesity of congenital cataract significant to vision, to determine the size of pseudophakic eye refraction while the child is growing, as well as to define the influential factors of refraction changes. All surgically corrected congenital cataract patients’ eye data were analyzed at a certain time period (01.01.2006.–31.12.2016) in a certain region (in Latvia). In the selection were included 87 congenital cataract patients, aged from 0 to 18 years with 137 eyes with pseudophakia. In the study were summarized, compared and investigated the characterizing values of congenital cataracts, statistically significant proportional differences were found of congenital cataracts, which demonstrate the uniqueness and heterogenicity of congenital cataract as a system. In the study the eye refraction changes with paeudophakia were studied, and their influential factors were proved and compared. Understanding the influential factors of the eye refraction changes, one may choose the most optimal aphakia correction method, to follow it up timely and to correct remains of refraction errors and their changes. In the study a statistically significant eye length boundary value was found, and by reaching it the eye refraction changes while the child is growing, which after the surgical correction of cataract extraction by intraocular implantation, will be comparatively smaller and more predictable. Different intraocular lens implantation techniques were found and compared and the eye’s individual intraocular lens power effect on the eye refraction changes was understood and compared.Statistically significant correlations were found and the process differences at different children ages in the operated eyes were defined. On the basis of the interdisciplinary (neonatologists, medical geneticians, paediatricians, paediatric ophthalmologists, cataract and anterior segment eye microsurgeons, optometricians, vision pedagogues) work experience, the study results and the literature data, there were design methodological recommendations for congenital cataract diagnosis, treatment and patients’ observation at Children’s Clinical University hospital in Latvia.