Relationship between supernormal sectors of retinal nerve fibre layer and axial length in normal eyes

AimsTo investigate the distribution and associations of the circumpapillary retinal nerve fibre layer thickness (RNFLT) profile, characterised as peak height and peak position, in healthy eyes.Methods667 healthy participants (294 male) were randomly selected from the Beijing Eye Study 2011. RNFLT was measured at 768 points at 3.4 mm circumpapillary position using spectral-domain optical coherence tomography (OCT). The location and height of the superior temporally peak (PeakST), superior nasal peak (PeakSN) and inferior temporal peak (PeakIT) were assessed.ResultsThe RNFLT was thickest at PeakIT (194±25 µm; location: 288±12°), followed by PeakST (182±25 µm; 73±10°) and PeakSN (125±23 µm; 135°±13°). In multivariable analysis, peak RNFLT decreased with longer axial length (p<0.001; correlation coefﬁcient beta: −0.18 to −0.15; all peaks), older age (all p<0.01, beta: −0.10; PeakST and PeakIT), female gender (p=0.026, beta: −0.09; PeakST), and larger parapapillary gamma zone and beta zone width (p≤0.004, beta: −0.16 to−0.11; PeakSN). The temporal peaks were located more closely to the horizontal line in women (p≤0.020, beta: 0.09–0.11) and with longer axial length (p<0.001, beta: 0.27–0.31), while they were located more inferiorly in eyes with larger Bruch’s membrane openings (BMOs) (p≤0.01, beta:0.10~0.11).ConclusionsPeak RNFLT decreased by 0.34 µm for each increase of year in age (PeakST and PeakIT), by 3.2–3.5 µm for each 1 mm increase in axial length (all three peaks), and was 4.5 µm thinner in women than in men. The position of temporal peaks depended on gender, axial length and BMO diameter. These associations should be taken into count in OCT-based RNFLT assessment for disease finding, especially in glaucoma evaluation.

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Effect of Refractive Status and Axial Length on Peripapillary Retinal Nerve Fibre Layer Thickness: An Analysis Using 3D OCT

JOURNAL FOR CLINICAL AND DIAGNOSTIC RESEARCH ◽

10.7860/jcdr/2015/14112.6480 ◽

2015 ◽

Author(s):

Sowmya V

Keyword(s):

Layer Thickness ◽

Nerve Fibre ◽

Axial Length ◽

Retinal Nerve Fibre Layer ◽

Fibre Layer ◽

Refractive Status ◽

Nerve Fibre Layer

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Retinal nerve fibre layer thickness of black and Indian myopic students at the University of KwaZulu-Natal

African Vision and Eye Health ◽

10.4102/aveh.v74i1.24 ◽

2015 ◽

Vol 74 (1) ◽

Author(s):

Chanel Murugan ◽

Bomikazi Z. Golodza ◽

Kaveshni Pillay ◽

Brightness N. Mthembu ◽

Praneal Singh ◽

...

Keyword(s):

Nerve Fibre ◽

Racial Differences ◽

Axial Length ◽

Total Sample ◽

Retinal Nerve Fibre Layer ◽

Spherical Equivalent ◽

Rnfl Thickness ◽

Fibre Layer ◽

Nerve Fibre Layer ◽

The University

Aim: To compare retinal nerve fibre layer (RNFL) thickness in black and Indian myopic students at the University of KwaZulu-Natal.Method: Eighty (40 black and 40 Indian) participants of both genders and aged between 19 and 24 years (mean and standard deviation: 21 ± 1.7 years) were included in the study. Refractive errors were assessed with the Nidek AR-310A auto-refractor and via subjective refraction. RNFL thicknesses were then measured using the iVue-100 optical coherence tomography device. Axial lengths were measured with the Nidek US-500 A-scan ultrasound device. Data were analysed by descriptive statistics, t-tests, Pearson’s correlation coefficients and regression analysis.Results: The mean myopic spherical equivalent was significantly more negative amongst the Indian (-2.42 D ± 2.22 D) than amongst the black (-1.48 D ± 1.13 D) (p = 0.02) participants.The mean axial length was greater amongst the black (23.35 mm ± 0.74 mm) than amongst the Indian (23.18 mm ± 0.87 mm) participants but the difference was not significant. In the total sample (n = 80), the average global RNFL thickness ranged from 87 μm to 123 μm (105 μm ±9 μm). Mean global RNFL thickness was slightly greater amongst black (108 μm ± 7 μm) than amongst Indian (102 μm ± 9 μm) (p = 0.00) participants. Mean global RNFL thickness was similar for male (106 μm ± 7 μm) and female (105 μm ± 10 μm) (p = 0.79) participants.A positive and significant association between myopic spherical equivalent and global RNFL thickness was found for the total sample (r = 0.36, p = 0.00) and for Indians (r = 0.33, p = 0.04)but not for the black (r = 0.25, p = 0.13) participants. There was a negative and significant correlation between axial length and global RNFL thickness amongst the Indian participants (r = -0.34, p = 0.03) but not amongst the total sample (r = -0.12, p = 0.30) or the black (r = 0.06, p = 0.73) participants.Conclusion: The findings suggest that racial differences in RNFL thickness need to be considered in the clinical examination and screening for glaucoma and other optic nerve pathologies amongst black and Indian people. Additionally, the possible influences ofrefractive error and axial length should be considered when evaluating RNFL thickness.

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Profile of retinal nerve fibre layer symmetry in a multiethnic Asian population: the Singapore Epidemiology of Eye Diseases study

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2019-314894 ◽

2019 ◽

Vol 104 (6) ◽

pp. 836-841 ◽

Cited By ~ 3

Author(s):

Yijin Tao ◽

Yih Chung Tham ◽

Miao Li Chee ◽

Shivani Majithia ◽

Sahil Thakur ◽

...

Keyword(s):

Nerve Fibre ◽

Axial Length ◽

Asian Population ◽

Retinal Nerve Fibre Layer ◽

Eye Diseases ◽

Optical Coherence ◽

Rnfl Thickness ◽

Fibre Layer ◽

Disc Area ◽

Nerve Fibre Layer

BackgroundTo examine the normative profile and determinants of retinal nerve fibre layer (RNFL) symmetry in a non-glaucoma, multiethnic Asian population.MethodsChinese, Malay and Indian adults aged ≥40 years were recruited from the Singapore Epidemiology of Eye Diseases study. Participants underwent standardised systemic and ocular examinations. RNFL thickness was obtained using a spectral-domain optical coherence tomography (Cirrus HD-OCT). RNFL symmetry (in %) was calculated based on Pearson correlation coefficient between the RNFL thickness profiles of the right and left eyes. Multivariable linear regression analysis was used to investigate the associations between ocular and systemic factors with RNFL symmetry.Results4211 participants (1227 Chinese, 1245 Malays, 1739 Indians) were included. The mean RNFL symmetry was 86.7%±8.5% in Chinese, 84.7%±10.2% in Malays and 84.0%±10.7% in Indians. The fifth percentile limit of RNFL symmetry was 71.2% in Chinese, 65.0% in Malays and 62.0% in Indians. In multivariable analysis adjusting for age, gender, ethnicity, hypertension, diabetes, hyperlipidaemia, intereye absolute differences in intraocular pressure (IOP), axial length and disc area, Malays (β=−0.9; p=0.03) and Indians (β=−1.76; p<0.001) were found to have lower RNFL symmetry compared with Chinese. Older age, greater intereye differences in IOP, axial length and disc area were significantly associated with lower RNFL symmetry (all p≤0.003).ConclusionsIn non-glaucoma individuals, intereye RNFL profile is less symmetric in Malays and Indians than that in Chinese. This also suggests that current commercial optical coherence tomography’s deployment of a single, universal RNFL symmetry cut-off for glaucoma detection is flawed, and ethnic-specific cut-off is warranted.

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