Corneal astigmatism in patients with various ophthalmic pathologies

Abstract

To analyze the prevalence, magnitude of corneal astigmatism, anatomical parameters of the eye and age of patients with the condition, as well as to assess the prospects of its correction with intraocular lenses (IOLs). The study involved a retrospective analysis of initial biometric data of 128 379 patients (256 630 eyes) referred to the S.N. Fedorov NMRC «MNTK «EYE MICROSURGERY» research center in the years 2013 to 2018. The patients previously operated for cataract were examined 6 months after surgery. In 5 years, corneal astigmatism of over 1.0 D was diagnosed in 66 610 (25.96%) eyes. Among them, low astigmatism was observed in 86.30% of cases, with-the-rule - in 56.10%, compound - in 78.72%, and astigmatism combined with myopic refraction - in 61.48%. More severe astigmatism is characterized by thinner cornea and lens (p<0.05). Cataract surgery with implantation of toric IOLs was performed only on 2.56% of eyes. The average age of the operated patients was 68.42±13.3. Patients with implanted toric IOLs had 23% better uncorrected visual acuity (UCVA), and 15% better corrected visual acuity compared with outcomes of spherical IOL implantation. Corneal astigmatism of more than 1.0 D was observed in 25.96% of examined subjects. Patients with corneal astigmatism apply for cataract surgery 10 years earlier, when they are still in the working age, due to inability to engage in professional activities; in most cases, those patients are female. Astigmatism of up to 0.75 D is more common on the right dominant eye, of 2.0 D and higher - on the left. The correlation coefficients determined for study data indicate a barely noticeable relationship between biometric parameters and the degree of astigmatism. The use of toric intraocular lenses provides a 2-fold increase in uncorrected visual acuity compared to spherical IOLs.