The Effects of Age, Optic Disc Size, and Signal Strength on Fourier-Domain Optical Coherence Tomography Measurements of the Nerve Fiber Layer, Optic Disc, and Ganglion Cell Complex

Abstract

 

Purpose:

 

To determine the correlation of patient and scan variables with peripapillary retinal nerve fiber layer (RNFL), optic disc, and macular ganglion cell complex (GCC) values in healthy eyes.

 

Methods:

 

248 healthy eyes from 8 clinics were enrolled. All participants underwent a full eye examination, standard achromatic perimetry (SITA- standard 24-2) and scanning with the RTVue, a Fourier-domain optical coherence tomography (FD-OCT device (Optovue, Inc.). All participants had normal visual fields (GHT within normal limits and PSD > 5%) and intraocular pressure < 22 mm Hg.

 

Results:

 

Descriptive statistics for the variables (mean +/- standard deviation) are shown in the table below.VCDR=vertical cup/disc ratio; SD=standard deviation; Avg = average; Sup=superior; Inf=inferior.Significant correlations were found between age and Avg RNFL, Superior ppNFL, Inf RNFL, and Avg GCC thickness values (p<0.05 for all, one-tailed test). Signal strength was significantly correlated with age, but no other parameter. Significant correlations were also found between optic disc size and VCDR (p<0.005), cup area (p<0.001), rim area (p<0.001), Avg RNFL (p<0.005), Sup RNFL (p<0.005), and Inf RNFL (P<0.025).  

 

Conclusions:

 

Significant effects for age and optic disc size were found for many RNFL, optic disc, and GCC parameters with a FD-OCT device. Anatomical measurements were not affected by signal strength.

 

Keywords: imaging/image analysis: clinical • optic nerve • ganglion cells