Determinants of quantitative optic nerve measurements using spectral domain optical coherence tomography in a population-based sample of non-glaucomatous subjects.
OBJECTIVE
To evaluate the ocular and systemic factors influencing measurements of optic nerve head (ONH) parameters and retinal nerve fiber layer (RNFL) thickness with spectral-domain optical coherence tomography (SD-OCT) in healthy Chinese adults.


METHODS
Adults ranging in age from 40 to 80 years were consecutively recruited from the population-based Singapore Chinese Eye Study. A SD-OCT instrument was used to measure ONH and RNFL parameters. A total of 542 eyes from 542 non-glaucomatous Chinese subjects were analyzed. Univariable and multiple linear regression analyses were performed to examine the effects of a range of ocular (e.g., intraocular pressure [IOP], axial length [AL], disc area) and systemic (e.g., blood pressure, serum glucose) factors on ONH and RNFL parameters.


RESULTS
In multiple regression analyses, neuroretinal rim area was independently associated with age (β = -0.006, P < 0.001), disc area (β = 0.183, P < 0.001), IOP (β = -0.009, P = 0.008), AL (β = -0.023, P = 0.004), and lens nuclear color (β = 0.042, P = 0.001). Vertical cup-to-disc ratio was independently correlated with age (β = 0.003, P < 0.001), disc area (β = 0.207, P < 0.001), IOP (β = 0.004, P = 0.014), AL (β = 0.010, P = 0.008), and lens nuclear color (β = -0.017, P = 0.006). Average RNFL thickness was independently related to age (β = -0.204, P = 0.001), disc area (β = 4.218, P < 0.001), signal strength (β = 1.348, P < 0.001), and AL (β = -1.332, P < 0.001). Disc area had the strongest effect on measurements of ONH parameters and RNFL thickness.


CONCLUSIONS
In a non-glaucomatous population, optic nerve measurements with SD-OCT vary with disc area, age, IOP, AL, lens nuclear color, and signal strength, but systemic parameters have little influence. This information may be useful for interpretation of SD-OCT measurements.
Singapore Eye Research Institute, Singapore National Eye Centre, Singapore.
Carol Y
CY
Cheung
David
D
Chen
Tien Y
TY
Wong
Yih Chung
YC
Tham
Renyi
R
Wu
Yingfeng
Y
Zheng
Ching Yu
CY
Cheng
Seang Mei
SM
Saw
Mani
M
Baskaran
Christopher K
CK
Leung
Tin
T
Aung
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D044466:Asian People; D058452:Axial Length, Eye / Q000033:anatomy & histology; D001794:Blood Pressure / Q000502:physiology; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers; D009898:Optic Disk / Q000033:anatomy & histology*; D009900:Optic Nerve / Q000033:anatomy & histology*; D012016:Reference Values; D012165:Retinal Ganglion Cells / Q000166:cytology*; D012846:Singapore / Q000453:epidemiology; D041623:Tomography, Optical Coherence