Variation of nerve fibre layer thickness measurements with age and ethnicity by scanning laser polarimetry

Abstract

Aims-Scanning laser polarimetry is a new technique allowing quantitative analysis of the retinal nerve fibre layer in vivo. This technique was employed to investigate the variation of the retinal nerve fibre layer thickness in a group of normal subjects of diVerent ages and ethnic groups. Methods-150 normal volunteers of different ages and ethnic groups were recruited for this study. Three consecutive 15 degree polarimetric maps were acquired for each subjects. Nerve fibre layer thickness measurements were obtained at 1.5 disc diameters from the optic nerve. Four 90 degree quadrants were identified. Results-The mean nerve fibre layer thickness varied from a minimum of 55.4 µm to a maximum of 105.3 µm, with a mean thickness value of 78.2 (SD 10.6) µm. Superior and inferior quadrants showed a comparatively thicker nerve fibre layer than nasal and temporal quadrants. Retinal nerve fibre layer thickness is inversely correlated with age (p < 0.001). White people showed thicker nerve fibre layers than Afro-Caribbeans (p = 0.002). Conclusion-The results indicate a progressive reduction of the nerve fibre layer thickness with increasing age. This may be due to a progressive loss of ganglion axons with age as suggested in postmortem studies. A racial diVerence in nerve fibre layer thickness is present between whites and Afro-Caribbeans. (Br J Ophthalmol 1997;81:350-354)

Determinants of Normal Retinal Nerve Fiber Layer Thickness Measured by Stratus OCT

“…Crosssectional studies of RNFL thickness using scanning laser polarimetry also have found a decrease in RNFL thickness with age. [9][10][11][12] The human RNFL loses approximately 5000 axons per year from birth to death, approximately 2500 per year before age 50 and 7500 per year after 50. 3 It is not surprising, then, that RNFL thickness decreases with age.…”

Scanning laser polarimetry in patients with acute angle-closure glaucoma

“…The details of this technique have been described previously. 12,13 A total of 65 536 retinal locations were measured to create a retardation map corresponding to RNFL thickness over a 151 (256 Â 256 pixel) retinal area. While undergoing scanning, the mean pupil diameters of the normal subjects were 2.870.3 mm and the mean pupil diameters of patients with AACG were 5.071.2 mm.…”

Study of Retinal Nerve Fiber Layer Thickness Within Normal Hemivisual Field in Primary Open-Angle Glaucoma and Normal-Tension Glaucoma

“…In addition, intersubject variation of NFLT, overlapping of NFLT between normal eyes and glaucomatous eyes, 1 and decrease in NFLT with aging 5,19,20 may make the study even more difficult. Therefore, in this study we selected patients with abnormalities localized either to the upper or to the lower hemifield, and compared NFLT measurements in the corresponding normal hemifield to evaluate the changes in NFLT before the development of visual field loss in glaucomatous eyes.…”