Abstract
Purpose:
Age is a risk factor for the development of glaucoma. Several studies suggest that normal aging could increase the susceptibility of the optic nerve head (ONH) to glaucomatous damage. We examined whether differences exist in lamina cribrosa and ONH structure in vivo between young and older normal subjects.
Methods:
Spectral domain optical coherence tomography (SDOCT) [Spectralis HRA+OCT] and adaptive optics scanning laser ophthalmoscope (AOSLO) images of the ONH and anterior lamina cribrosa surface (ALCS) microarchitecture were acquired in eyes of 22 young (20-30 years) and 16 older (≥ 50 years) normal human subjects. ONH features were manually marked in SDOCT radial B-scans to calculate Bruch’s membrane opening (BMO) area, mean ALCS depth, mean ALCS radius of curvature (RoC), prelaminar tissue volume (PTV), mean minimum rim width (MRW) and rim volume. Anterior laminar pores were manually marked in AOSLO images and 3D transformed to calculate mean global pore area, elongation and nearest neighbor distance (NND). A Mann-Whitney rank sum test was used to assess statistical differences in all parameters between young and older eyes.
Results:
No statistical differences were measured between young and older normal eyes in any ONH or mean global pore parameters. Among the ONH parameters, mean MRW was not significantly reduced in young vs older subjects (317.6 ± 50.0 µm vs 289.8 ± 43.0 µm, P=.08), nor was PTV (1.04 ± 0.16 mm3 vs 0.95 ± 0.16 mm3, P=.16). Mean ALCS depth was similar between young (363.9 ± 78.4 µm) and older (352.7 ± 75.71 µm) groups (P=.96), as were BMO area (P=.76), mean RoC (P=.87) and rim volume (P=.51). Mean pore area (young = 2055 ± 561 µm2, older = 2292 ± 744 µm2), elongation (young = 2.06 ± 0.30, older = 2.00 ± 0.30) and NND (young = 75.24 ± 14.5 µm, older = 88.65 ± 25.10 µm) were not significantly different between young and older eyes (P=.39, .37 and .09, respectively).
Conclusions:
ONH and mean global laminar pore parameters were similar between our groups of young and older normal eyes. Further analyses are required to determine whether anterior laminar microarchitecture is significantly different on a local scale between age groups. In addition to providing a better understanding of age-related changes in laminar and ONH structure, these normative data will be used for future comparison with values measured in glaucoma patients.
Keywords: 413 aging •
552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
577 lamina cribrosa