BACKGROUNDAssessment of the optic disc and retinal nerve fiber layer (RNFL) is essential for the diagnosis and monitoring of glaucoma. Knowledge of normal optic disc topography provides a benchmark for evaluating glaucomatous pathologic changes, especially in its early stages. The purpose of this study was to evaluate the characteristics and correlation factors of the optic disc parameters using the Heidelberg Retina Tomograph II (HRT II) in a large sample of normal eyes of adult Chinese subjects.

METHODSDisc data were obtained from 6 830 subjects aged >30 years from the Handan Eye Study. All participants underwent comprehensive eye examinations and physical examinations. The associations of gender, age, body mass index, blood pressure, waist-to-hip ratio; refractive error, intraocular pressure, axial length, and disc area were assessed using simple and multiple regression analysis. The correlation between HRT II parameters was evaluated.

RESULTSOf the 7 557 eligible subjects, 6 830 took part in the study (90.4% response rate) and 2 633 normal eyes with good-quality HRT II images were selected. The mean disc area was 2.28 mm(2) (standard deviation (SD) 0.43) and mean neural rim area was 1.80 mm(2) (SD 0.29). In multiple regression analysis, optic disc area significantly correlated with age, gender, and axial length (P < 0.001). All optic disc parameters showed a significant correlation with disc area (0.054

CONCLUSIONSThe optic disc area in rural Chinese population is larger than reported in white and Japanese populations, similar to that of Indian population and urban Chinese population. Most optic disc measurements were moderately or weakly affected by disc area. In addition to the RNFL, there may be other factors affecting the rim area. The relationship between optic disc and axial length may suggest a link between larger disc area, thinning of the lamina cribrosa, and increased glaucoma susceptibility in myopic eyes.

Adult ; Female ; Glaucoma ; epidemiology ; Humans ; Male ; Middle Aged ; Myopia ; epidemiology ; Optic Disk ; anatomy & histology

We conducted an investigation of the relation between RNFL thickness and optic disc size along with an interocular comparison of optic disc size, RNFL thickness, and RNFL density in healthy subjects. A total of 64 normal eyes from 32 Korean volunteers were enrolled in this study. A GDx Nerve Fiber Analyzer with software version 2.0.09 was used to image all subjects. Optic disc size was measured by pi x (horizontal radius) x (vertical radius). The RNFL density of each quadrant was calculated by dividing each quadrant integral by the total integral. Optic disc size was positively correlated with the total RNFL thickness (r = 0.615, p < 0.01). Optic disc size and RNFL density were inversely related in the superior quadrant (r = -0.248, p < 0.05). There was a significant positive correlation between optic disc size and RNFL density in the nasal quadrant (r = 0.439, p < 0.01) and the temporal quadrant to a certain degree. A significant positive correlation was found between the right and left eyes in terms of total RNFL thickness in and that of each quadrant. Interocular RNFL density was positively correlated in both the temporal and nasal quadrants. These findings must be considered when one evaluates and compares RNFL measurements between two eyes as is often the case where both eyes are usually affected in the course of glaucomatous RNFL damage.
Adult ; Comparative Study ; Female ; Human ; Lasers/diagnostic use ; Male ; *Nerve Fibers ; Optic Disk/*anatomy & histology ; Optic Nerve/*anatomy & histology ; Perimetry ; Weights and Measures

We have investigated the potential usefulness of stereoscopic viewing of optic disc photographs in marking the disc margin in computerized analysis with the Rodenstock Analyzer in 48 eyes of 26 patients with ocular hypertension or primary open-angle glaucoma. Marking of the disc margin without Method 1) and with the aid of stereoscopic viewing of disc photographs (Method 2) three consecutive times by one observer at the same sitting, and three subsequent topographic analyses of each method were done on each 48 eyes. The mean intraphotographic variabilities of such optic disc parameters as rim area, and cup volume with Method 2 were significantly less than those with Method 1 overall and in 16 eyes (33%) with poor video images having an ill-defined disc margin (p less than 0.05 for each), but not in 32 eyes (67%) with clear video images having a well-defined disc margin. Furthermore, the mean paired differences of rim area, disc area and cup volume between the two methods (Method 1 minus Method 2) were also statistically significant overall and in eyes with poor video images (p less than 0.05 for each).
Adult ; Aged ; Female ; Glaucoma, Open-Angle/pathology ; Human ; *Image Interpretation, Computer-Assisted ; Male ; Middle Age ; Ocular Hypertension/diagnosis ; Optic Disk/*anatomy & histology/pathology ; Photography

Purpose: To determine the proportion of glaucoma suspects with abnormal nerve fiber layer measurement using GDx nerve fiber analyzer Methodology: The study population consisted of glaucoma suspects between ages 30-70 years, who underwent glaucoma workup including retinal nerve fiber layer measurement (GDx NFA) Results: 35 eyes of glaucoma suspects were analyzed. 28/35 were found to have normal NFL thickness; 5/35 have 1 abnormal GDx parameters; 1/35 with 3 abnormal GDx parameters; 1/35 with 3 GDx abnormal parameters. Linear regression analysis showed no correlation between C:D and GDx parameters Conclusion: This study confirms that superior maximum is useful to the other parameters but there is a need to collect more samples. (Author)
Human ; Male ; Female ; Aged ; Middle Aged ; Adult ; RETINA/ANATOMY & HISTOLOGY ; NERVE FIBERS ; GLAUCOMA ; HUMAN ; OPTIC DISK ; SCANNING LASER POLARIMETRY ; LASER/DIAGNOSTIC USE

BACKGROUNDRTVue spectral-domain optical coherence tomography (OCT) is a new, ultra high-speed and high-resolution instrument, potentially to measure the presence of glaucoma or its progression accurately. The objective of this study was to evaluate its reproducibility of retinal nerve fiber layer (RNFL) thickness and optic nerve head (ONH) measurements in normal and glaucoma eyes.

METHODSThis study was an observational clinical study. One eye was selected randomly from each of 89 normal individuals and 63 glaucoma patients in a range of severity. RNFL thickness and ONH were measured 3 times on the same day to determine intrasession variability. The same instrument was used by the same operator for all scans. Intrasession within-subject standard deviation (Sw), precision (1.96 x Sw), coefficient of variation (CVw, 100 x Sw/overall mean), and intraclass coefficient (ICC) were calculated to evaluate reproducibility.

RESULTSRTVue OCT demonstrated double hump patterns in the RNFL profiles. High reproducibility was observed in all ONH parameters. For normal eyes, the value of ICC ranged between 0.98 and 1.00. For eyes with different extent of glaucoma, it ranged between 0.94 and 1.00. High reproducibility was also observed in RNFL thickness measurements. The values of ICC for averaged RNFL thickness ranged between 0.95 and 1.00 in all cases. For regional parameters, it ranged from 0.94 to 0.98 for normal eyes, 0.94 to 1.00 for mild glaucoma eyes, 0.87 to 1.00 for moderate glaucoma eyes, and 0.77 to 0.97 for severe glaucoma eyes. The nasal regions of severe glaucoma appeared to be most variable, as nasal lower region and inferior nasal region had the ICC values of 0.77 and 0.87.

CONCLUSIONReproducibility of RTVue RNFL and ONH measurements was excellent in normal and glaucoma groups.

Adult ; Aged ; Cross-Sectional Studies ; Female ; Glaucoma ; pathology ; Humans ; Male ; Middle Aged ; Nerve Fibers ; Optic Disk ; anatomy & histology ; pathology ; Tomography, Optical Coherence ; methods ; Young Adult

PURPOSE: To assess the impact of axial length on the age-related peripapillary retinal nerve fiber layer (RNFL) thinning. METHODS: This cross-sectional observational comparative case series included 172 eyes from 172 healthy Korean subjects. Peripapillary RNFL thickness was measured using an Optic Disc Cube 200 x 200 scan of spectral domain Cirrus HD OCT and the axial length was measured using IOL Master Advanced Technology. In age groups based on decade, the normal ranges of peripapillary RNFL thickness for average, quadrant, and clock-hour sectors were determined with 95% confidence intervals. After dividing the eyes into two groups according to axial length (cut-off, 24.50 mm), the degrees of age-related RNFL thinning were compared. RESULTS: Among the eyes included in the study, 53 (30.81%) were considered to be long eyes (axial length, 25.04 +/- 0.48 microm) and 119 (69.19%) were short-to-normal length eyes (axial length, 23.57 +/- 0.60 microm). The decrease in average RNFL thickness with age was less in long eyes (negative slope, -0.12 microm/yr) than in short-to-normal length eyes (negative slope, -0.32 microm/yr) (p < 0.001). CONCLUSIONS: Age-related thinning of peripapillary RNFL thickness is attenuated in long eyes compared to short-to-normal length eyes.
Adult ; Aged ; Cross-Sectional Studies ; Eye/*anatomy & histology ; Female ; Humans ; Macular Degeneration/*epidemiology/pathology ; Male ; Middle Aged ; Nerve Fibers/*pathology ; Optic Disk/*pathology ; Prevalence ; Republic of Korea/epidemiology ; Retinal Ganglion Cells/*pathology ; Severity of Illness Index ; *Tomography, Optical Coherence

PURPOSE: To evaluate the reproducibility of ImageJ software in analyzing the color of the optic disc. METHODS: One hundred twelve normal participants (56 males and 56 females) were enrolled in this study. The image of the optic disc was taken using Kowa digital disc photo-graphy, and the gray scales of the nasal rim (NR), brightest cupping center (BCC) and largest inferior retinal vein (IRV) were calculated using histogram in ImageJ. Three different observers calculated the gray scales three separate times. Reproducibility was assessed using the interclass correlation coefficient (ICC). RESULTS: The mean age of the participants was 50.6 years old (range, 11 to 82 years). The mean gray scales of the nasal rim were 91.81, 94.91, and 93.24; those of the brightest cupping center were 174.84, 179.94, and 177.76; and those of the largest inferior retinal vein were 61.85, 53.48, and 56.73 for observers 1, 2, and 3, respectively. Inter-observer reproducibility for NR, BCC and IRV was considered good based upon ICC values of 0.944, 0.860, and 0.789 for observers 1, 2, and 3, respectively. Significant age-related differences between the values of the brightest cupping center were noted, and the gray scale score was decreased in the older participants (p < 0.001). CONCLUSIONS: The gray scale of the brightest cupping center diminished with age. ImageJ can be a useful objective tool with high reproducibility in the analysis of optic disc color.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Color ; Female ; Humans ; Image Processing, Computer-Assisted/*methods ; Male ; Middle Aged ; Optic Disk/*physiology ; Organ Size ; Photography ; Reference Values ; Reproducibility of Results ; Retinal Vein/anatomy & histology ; *Software ; Young Adult