Comparative Studies in the Northern Finland Birth Cohort Eye Study

The aim of this ophthalmological thesis is to evaluate examination methods regarding 1) the evaluation of refraction and visual acuity, 2) the assessment of intraocular pressure with three different devices, and 3) the evaluation of the parameters of retinal nerve fiber layer and optic nerve head with three imaging devices. Additionally, this thesis gives information on the ocular features mentioned above. The subjects of three of the publications were members of the NFBC1966, Northern Finland Birth Cohort 1966. The current eye study was conducted in conjunction with the 46-year follow-up of the NFBC. A total of 10 321 cohort members living in Finland were randomised and 3 070 (60% of the eye screening group responded) were included in the eye study. The subjects of one of the publications were members of the Northern Finland Birth Cohort 1986.

Our study showed that visual acuity and refraction can be evaluated relatively reliably with an autorefractometer, but the method may not be optimal when best corrected visual acuity is in a crucial role. When measuring intraocular pressure, the results of rebound tonometer iCare correlate well with the reference standard, Goldmann applanation tonometer, but they should not be used interchangeably. The results of rebound tonometers iCare TA01i and iCare IC100 are close to each other, and iCare IC100 is suitable for use in large screening studies. When comparing the parameters obtained with the imaging devices (OCT, HRT and GDx), the correlation is high for cup and disc parameters of OCT and HRT, but substantially lower for retinal nerve fiber layer, image quality and glaucoma detection parameters.