The Normal Thickness of the Ganglion Cell Complex in the Macula measured with RTVue OCT

Abstract

Purpose: : To determine the normal thickness of the ganglion cell complex in the macula region measured with the RTVue, a fourier-domain OCT, and to evaluate the relationship with age and possible ethnic differences.

Methods: : 861 eyes were collected at 15 clinical sites worldwide with the average age being 50.7 years old (range 19-82 years). Eligible subjects were over 18 years old, free from known ocular pathology, had IOP below 22 mm Hg, and a full visual field test based on the Humphrey 24-2 SITA Standard perimetry. Optic disc appearance was not used as an exclusion criterion to avoid bias in the database.

Results: : The table lists the mean GCC thickness and standard deviation (SD) by ethnicity. Significant ethnic differences were found (p < .001) even when age effects were taken into account.

Conclusions: : The GCC in the macula may be an important area of interest for detecting early glaucoma. Significant ethnic differences were found in the GCC thickness. Thus it may be important for an instrument to use an ethnic-specific database which automatically adjusts the normative range and cut-offs to account for both age and GCC effects.

Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • ganglion cells • macula/fovea