[Investigation of the impact of pterygium on ocular optic system aberration. Communication 1. Relationship of induced aberrations to the stage of pterygium].

The authors made a study in two areas: they investigated corneal aberrations in patients from different age groups in health; analyzed the corneal aberration pattern at different stages of pterygium in the matched age groups; and comparatively estimated values in pterygium and in health in the similar age groups. High-order aberrations (HOA) of the corneal were studied in 45 patients (84 eyes) aged 20 to 76 years. The corneal aberration pattern was analyzed in 44 patients (55 eyes) aged 25 to 74 years who had pterygium of different stages. The study covered patients with Stages II (24 eyes), III (n=20), and IV (n=11). The results of corneal HOA in health suggest that coma aberrations significantly increase with age while the rise of spherical aberrations is not decisive. Comparative analysis of aberrations in health and in pterygium of different stages showed that its stage II causes no significant changes in the corneal aberration pattern; the characteristic features of the latter in Stages III and IV pterygium are increases in trefoil and aberrations of the fourth and fifth orders: tetra- and pentafoil, secondary trefoil. The increase in the above parameters is proportional to the stage of pterygium. The comprehensive examination of patients with pterygium of different stages should comprise a study of corneal HOA, it is required for more detailed evaluation of disorders induced by the extent of pterygium, which in turn makes it possible to optimize the latter's removing technology.