Posters

Relationship of retinal vessel diameter with retinal nerve fiber layer thickness: The Northern Finland Birth Cohort Eye study (NFBC Eye study)

Poster Details

First Author: M.Geneid FINLAND

Co Author(s): J. Kettunen   I. Nuuttila   T. Lintonen   V. Saarela   J. Liinamaa        

Abstract Details

Purpose:

To study the relation between retinal vessel diameter (RVD) and retinal nerve fiber layer (RNFL) thickness in normal population. Previous studies have been conducted with children or adolescents in various ethnic populations.

Setting:

A cohort study of normal population of middle-aged Caucasians. This cohort is a part of the Northern Finland Birth Cohort (NFBC), known as NFBC Eye study.

Methods:

Retinal vessel calibers were measured using the semi-automated IVAN software version 1.3. Briefly, six largest arterioles and venules passing completely through a circumferential zone 0.5 to 1 disc diameter from the optic disc margin were automatically identified and their diameter measured by IVAN program. Two variables were calculated: central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE), using the revised Parr–Hubbard formula. Three graders masked to participant’s characteristics measured the RVDs of all participants in the right eye. RNFL thickness was assessed with Heidelberg retinal tomography (HRT).

Results:

Cohort study included 3070 persons and 6140 eyes. Data of 2250 persons was analyzed including RNFL, CRAE, CRVE, glaucoma, sex, BMI, mean arterial pressure, diabetes status, smoking status, optic disc area, rim area, spherical refraction, IOP). Each standard deviation decrease in arteriolar and venular caliber was associated with a 8.00- and 7.45-µm decrease, respectively, in mean global RNFL thickness (both P < 0.001). These associations remained similar after persons with glaucoma (n=56) were excluded. In persons with glaucoma, retinal vascular caliber was independently associated with the temporal, nasal-to-inferior and temporal-to-inferior region of mean RNFL thickness in sex-adjusted analysis.

Conclusions:

We found strong associations between narrower retinal vessel caliber and thinner RNFL in all subjects in global and inferior segments of the retina, also when glaucoma cases were excluded. This study helps in understanding the association between retinal vascular caliber and the RNFL thickness and gives normal values for middle-aged Caucasians. This data is essential in future studies of vascular etiology in eye diseases affecting also RNFL.

Financial Disclosure:

None