Abstract
Purpose: :
To determine the determinents of ganglion cell complex (GCC) layer thickness in normal healthy Chinese eyes measured by high-definition optical coherence tomography (OCT)
Methods: :
506 Chinese adults aged 40 to 80 years were consecutively recruited from the population-based Singapore Chinese Eye Study. All subjects underwent a standardized interview and ophthalmic examination including automated perimetry. High-definition OCT (Cirrus, software version 6.0, Carl Zeiss Meditec Inc, Dublin, CA) with macular cube 512 x 128 acquisition protocol was used to measure the ganglion cell complex (GCC) layer thickness. Univariate and multiple linear regression analyses were performed to examine the relationship between GCC thickness with age, gender, ocular factors and systemic factors.
Results: :
The mean (± SD) age of study subjects was 53.0 ± 6.5 years, 49.1% was male and mean spherical equivalent was -1.12 ± 2.59 diopters. All subjects had normal and reliable visual field tests. The mean overall, minimum, superior and inferior GCC layer thickness was 82.08 ± 6.71µm, 78.92 ± 9.68µm, 82.69 ± 7.54µm and 79.40 ± 8.72µm, respectively. In multiple linear regression analysis, GCC layer thickness was significantly associated with age (β = -0.174, P <0.001), best-corrected visual acuity (β = -0.206, P <0.001), axial length (β = -0.40, P <0.001), Humphrey visual field (HVF) mean deviation (β = 0.171, P = 0.028) and mean retinal nerve fiber layer thickness (β = 0.373, P <0.001). Blood pressure, intra-ocular pressure and central cornea thickness were not significantly associated with GCC layer thickness
Conclusions: :
In non-glaucomatous Chinese eyes, thinner GCC layer thickness was associated with older age, worsening best-corrected visual acuity, longer axial length, larger HVF mean deviation and thinner retinal nerve fiber layer thickness. These factors should be taken into account when interpreting Cirrus OCT-based GCC layer thickness measurements.
Keywords: ganglion cells • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • nerve fiber layer