Corneal Biomechanical Parameters after 60-Year-Old

Fereshteh Shokrollahzadeh; Hassan Hashemi; Abbasali Yekta; Hadi Ostadimoghaddam; Mehdi Khabazkhoob

doi:10.4103/joco.joco_201_21

Corneal Biomechanical Parameters after 60-Year-Old

J Curr Ophthalmol. 2022 Nov 30;34(3):284-289. doi: 10.4103/joco.joco_201_21. eCollection 2022 Jul-Sep.

Authors

Fereshteh Shokrollahzadeh¹, Hassan Hashemi², Abbasali Yekta¹, Hadi Ostadimoghaddam³, Mehdi Khabazkhoob⁴

Affiliations

¹ Department of Optometry, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran.
² Noor Research Center for Ophthalmic Epidemiology, Noor Eye Hospital, Tehran, Iran.
³ Refractive Errors Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
⁴ Department of Basic Sciences, School of Nursing and Midwifery, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Abstract

Purpose: To determine the distribution of corneal biomechanical parameters in an elderly population.

Methods: This cross-sectional study was conducted in subjects above 60 years living in Tehran. The participants were selected using multi-stage cluster sampling. Corneal biomechanical parameters were measured in a randomly selected subsample of this population using the Reichert Ocular Response Analyzer (Reichert Ophthalmic Instruments, Inc., Buffalo, NY, USA).

Results: Of 470 subjects, the data of 420 participants aged over 60 years were analyzed (mean age: 69.3 ± 6.5 years and range: 61-88 years), 363 (86.4%) of whom were male. The mean and standard deviation of corneal hysteresis (CH) and corneal resistance factor (CRF) were 8.37 ± 1.55 mmHg (95% confidence interval [CI]: 8.02-8.72) and 9.06 ± 1.70 mmHg (95% CI: 8.69-9.44), respectively. The mean CH was 8.27 ± 1.54 mmHg in men and 9.25 ± 1.28 mmHg in women, and the mean CRF was 9.00 ± 1.71 mmHg in men and 9.63 ± 1.37 mmHg in women. According to the results of multiple linear logistic regression analysis, CH had a significant association with younger age (β = -0.05, P = 0.032), female sex (β = 1.83, P < 0.001), reduced maximum keratometry (β = -0.22, P = 0.06), and increased anterior chamber volume (β = 0.01, P = 0.007). CRF had a significant correlation with a younger age (β = -0.06, P = 0.02), female sex (β = 1.01, P = 0.05), central corneal thickness (β = 0.02, P < 0.001), and reduced maximum keratometry (β = -0.39, P = 0.010).

Conclusion: The mean CH and CRF values were low in this sample of the Iranian population aged over 60 years indicating the weaker elasticity of the corneal connective tissue.

Keywords: Cornea; Corneal biomechanics; Corneal hysteresis; Corneal resistance factor.