ABSTRACT
@#AIM:To investigate the influence of myopia on peripapillary retinal nerve fiber layer thickness(RNFLT)using Cirrus optical coherence tomography(OCT)in myopic juveniles aged 12-18 years.<p>METHODS: Cross-sectional observational study. High-definition(HD), spectral-domain Cirrus OCT(Cirrus HD-OCT; Carl Zeiss, Dublin, CA)was used to analyze RNFLT in 145 healthy juveniles(145 eyes). The data for left eye were selected for analysis. The magnification effect was adjusted by the modified axial length method. The subjects were divided into four groups by spherical equivalent(SE): normal group(52 eyes, -0.25-+0.25D), low myopia group(60 eyes, -0.5--3.0D), moderate myopia group(25 eyes, -3.25--6.0D)and high myopia group(8 eyes,-6.25--12.0D). The correlations between RNFLT and axial length(AL)or SE was tested with linear regression analysis.<p>RESULTS: The older the age, the longer the eye axis length, the higher the degree of myopia. Comparison of adjusted RNFLT among the four groups: after adjustment, the average RNFLT of the low myopia group and the moderate myopia group were thicker than those of the normal control group(<i>P</i><0.05). The adjusted RNFLT of temporal quadrant in the moderate myopia group and the high myopia group were significantly thicker than those in the normal group and the low myopia group, as well as the adjusted RNFLT of nasal quadrant in the low, moderate myopia group were significantly thicker compared with those in the normal group(<i>P</i><0.05). There were statistically significant difference of adjusted RNFLT at 1-4 o'clock, 6 o'clock, 7 o'clock and 9 o'clock among multiple groups(<i>P</i><0.05). The adjusted values of RNFLT at 1-4 o'clock all showed positively correlated with AL(<i>r</i>=0.220, 0.259, 0.356, 0.237, 0.335, all <i>P</i><0.01)and negatively correlated with SE(<i>r</i>=-0.386, -0.276,-0.307, -0.254, -0.260, all<i> P</i><0.01); The adjusted RNFLT at 6, 7 o'clock showed negatively correlated with AL(<i>r</i>=-0.296,-0.327, all<i> P</i><0.01)and positively correlated with SE(<i>r</i>=0.245,0.295, all<i> P</i><0.05).<p>CONCLUSION: Teenagers' eyeballs are still in the shaping stage. When judging RNFLT in myopic juveniles, effects of ocular magnification effect, AL and SE should be considered. When adjusted temporal RNFLT at 1-4 o'clock are thinner than normal, glaucoma should be considered.
ABSTRACT
Abstract?AIM:To compare the loss of peripapillary retinal nerve fiber layer ( RNFL ) thickness measurements by spectral-domain optical coherence tomography ( SD -OCT ) in healthy individuals and glaucoma patients with or without progression.? METHODS: A total of 60 eyes, comprising 36 glaucomatous eyes with primary open angle glaucoma (POAG) and 24 healthy controls, were included in the study over a 2-year period.All eyes underwent at least 4 serial RNFL measurements performed by Cirrus OCT every half a year over a period of 2a.Visual field ( VF) testing was performed by using the Swedish interactive threshold algorithm( SITA) Standard 30-2 program of the Humphrey field analyzer within the same week as the optic disc/RNFL photography. By masked comparative analysis of VF test results and optic disc/RNFL photographs, the eyes were classified into non -progressive and progressive glaucoma cases. Longitudinal loss of RNFL thickness was compared.?RESULTS: The mean follow-up time was 2.1 ±0.3a. Seventeen from 36 subjects were identified as progressors. Mean rates of change in average RNFL thickness were significantly higher for progressors compared with nonprogressors (2.46μm/a vs.1.21μm/a;P <0.001 ). Inferior quadrant RNFL thickness were significantly correlated with MD reduction in glaucoma eyes with progression(r=0.423, P=0.03).? CONCLUSION: Longitudinal measurements of RNFL thickness using SD-OCT show a pronounced reduction in patients with progression compared with patients without progression.Inferior RNFL thickness parameters might be more important in discriminating eyes with progressive glaucomatous optic nerve damage.