Low and high order aberrations in the eyes of patients with levothyroxine treated hypothyroidism — comparison and analysis

Abstract

Background: There is an increasing number of patients in optometric practices who suffer from hypothyroidism. Thyroid diseases have an impact on the ocular condition, refraction, and tear film stability, particularly when thyroid is hyperreactive. This research is focused on the optical condition of the eyes in patients with hypothyroidism treated with levothyroxine to assess its importance during refraction exams. Material and methods: A group of 43 patients was examined, their medical case history was taken, and aberrometry was performed. A research and control groups were selected for statistical analysis of the obtained results. Refractive condition, keratometry, whole eye aberrometry, and separately cornea and internal aberrometry were performed with the use of iTrace aberrometer, based on ray-tracing aberrometry and Placido disk corneal topography. Results: Statistically significant differences with a threshold of p = 0.05 were total eye horizontal coma and corneal horizontal secondary coma. Three values were slightly above the threshold — whole eye oblique tetrafoil, corneal vertical pentafoil, and internal horizontal coma. All three parameters have a p-value equal to 0.06. Conclusion: Hypothyroidism treated with levothyroxine does not have a significant impact on the ocular surface or internal eye aberrations of low order. However, in case of total eye horizontal coma and secondary corneal horizontal coma, the differences are statistically significant.