Pattern of retinal nerve fiber layer damage in Korean eyes with normal-tension glaucoma and hemifield visual field defect

PURPOSE: To evaluate quantitatively the pattern of retinal nerve fiber layer (RNFL) damage in eyes with normal-tension glaucoma (NTG) with hemifield dominant visual field defects using scanning laser polarimetry. METHODS: Prospectively, 40 consecutive eyes from 40 patients with NTG and hemifield defect based on the findings of examination using the Humphrey Field Analyzer underwent RNFL thickness measurements. Twenty normal eyes from 20 subjects matched in age and refractive error formed a control group. RESULTS: Symmetry, calculated as the ratio of superior to inferior RNFL thickness, showed no statistically significant difference between the study group and the control group ( P=0.50). Overall, 27.5% (11/40 eyes) showed an "abnormal" symmetry index that indicated focal RNFL change. The affected ratio, calculated as the ratio of RNFL thickness in the quadrant corresponding to the hemifield of visual field defect to that of the temporal quadrant was significantly lower in the study group than in the control group ( P<0.0001). A similar finding was noted for the unaffected ratio. CONCLUSION: Despite strict selection of the eyes with visual field defect confined to one hemifield, a mixture of both focal and diffuse RNFL damage was noted, with a common occurrence of symmetrical RNFL thinning in both upper and lower quadrants based on scanning laser polarimetry.     

Analysis of retinal nerve fiber layer thickness measured by optical coherence tomography in glaucomatous eyes with hemifield defect

PURPOSE: To analyze the retinal nerve fiber layer thickness(NFLT) as measured by optical coherence tomography(OCT) in glaucomatous eyes with hemifield defect and to evaluate the most effective parameter for the diagnosis of glaucoma with OCT. METHODS: One hundred eighty four(184) normal eyes(128 subjects) and 108 open-angle glaucomatous eyes(87 subjects) with superior or inferior hemifield defects verified by Humphrey field analyzer(HFA) were measured for NFLT with OCT. The correlations between NFLT and mean deviation on HFA were calculated. In combination with normal eye data, receiver operating characteristic curve(ROC curve) and AUC(area under the curve) of each NFLT in the affected hemifield were evaluated for the diagnosis of glaucoma. RESULTS: NFLT in both affected and unaffected hemifields was significantly correlated with mean deviation in HFA. An average of four 30 degrees segments close to the temporal side in the affected hemifield (parameter A120) had the highest correlation(r = 0.571) and the highest AUC(0.948) among all parameters. CONCLUSIONS: NFLT in the unaffected visual field decreases with the progression of glaucomatous damage. We suggest that the parameter A120 is the best indication in a diagnosis of glaucoma when measuring NFLT by OCT.     

Asymmetries of the retinal nerve fibre layer thickness in normal eyes

AIMS: To investigate the variation in the retinal nerve fibre layer thickness in detail in normal eyes with a scanning laser polarimeter. METHODS: The retinal nerve fibre layer thickness (RNFLT) was measured in 94 normal volunteers with a scanning laser polarimeter. The mean RNFLT around a 10 pixel-wide ellipse located concentrically with the disc of 1.5 disc diameters was calculated for 16 sectors each of 22.5 degrees. The symmetry of the RNFLT distribution with respect to the horizontal midline for individual eyes and to the vertical meridian for the two eyes was examined. RESULTS: The RNFLT was thicker on the inferior side than on the superior side for the temporal four pairs of 22.5 degrees sectors, and the differences were significant in two of the four temporal pairs (p<0.007). The RNFLT was thicker in the superior than in the inferior side for the nasal four pairs of the sectors, and the differences were significant in three of the four nasal pairs (p<0.04). The mean RNFLT was significantly thicker in the right eyes than in the left eyes in the four temporal sectors (p<0.02), and significantly thicker in the left eyes than in the right eyes in the inferior two nasal sectors (p<0.01). CONCLUSIONS: Asymmetries of the RNFLT in normal eyes with respect to the horizontal midline and to the vertical meridian for the two eyes were found. These asymmetries should be considered when retinal nerve fibre layer loss is evaluated during the course of a disease process.     

Thinner retinal nerve fibre layer in healthy myopic eyes with thinner central corneal thickness

Graefe's Archive for Clinical and Experimental Ophthalmology - Thinner central corneal thickness (CCT) is a risk factor for conversion from ocular hypertension to glaucoma and for disease...     

Rates of retinal nerve fibre layer thickness change in glaucoma patients and control subjects

Purpose

To examine the rates of retinal nerve fibre layer thickness (RNFLT) change in glaucoma patients and healthy, age-similar control subjects with three techniques: scanning laser polarimetry with variable corneal compensation (VCC) and enhanced corneal compensation (ECC), and time-domain optical coherence tomography (OCT).

Methods

Sixty-one patients and thirty-three controls were examined with each technique and with standard automated perimetry (SAP) every 6 months. Rates of global RNFLT change and SAP mean deviation (MD) change were estimated with linear mixed-effects models.

Results

The median (interquartile range) baseline age was 64.4 (58.2, 71.0) years for patients and 62.4 (56.3, 70.1) years for controls (P=0.56). There was a median of seven examinations over 3.1 years for patients and six examinations in 3.0 years for controls. Baseline visual field MD and RNFLT for all imaging modalities were significantly lower (P<0.01) in patients compared with controls. Rates of RNFLT change were not significantly different between patients and controls (P≥0.19). Mean rates of VCC-measured RNFLT change were −0.18 and −0.37 μm per year in patients and controls, whereas the respective figures for ECC and OCT were −0.13 and −0.31 μm per year, and 0.04 and 0.61 μm per year. Mean rates of MD change were −0.20 and 0.03 dB per year in patients and controls, respectively (P=0.01).

Conclusion

Rates of RNFLT change in glaucoma patients were not statistically different from control subjects for any modality. A significantly negative rate of MD change in patients suggests a genuine, continued deterioration in these patients not reflected by RNFLT changes.     

Quantification of the retinal nerve fibre layer thickness in normal Indian eyes with optical coherence tomography

PURPOSE: To quantitatively assess the normative values for peripapillary retinal nerve fibre layer (RNFL) thickness with Optical Coherence Tomography (OCT 3) in Indian subjects. METHODS: The peripapillary retinal nerve fibre layer of 146 normal subjects was imaged on OCT 3 in this cross-sectional study. Thickness of the RNFL around the disc was determined with three 3.4 mm diameter circle OCT scan. The RNFL thickness was measured in four quadrants; superior, nasal, inferior and temporal. The data was analysed using SAS commercial statistical software. Influence of age and gender was evaluated on various measured parameters using unpaired t test, one-way analysis variance (ANOVA) and Pearson's correlation coefficient. RESULTS: One hundred and forty six eyes of 146 patients, 84 males and 62 females were studied. The average RNFL thickness in the sample population under study was 104.27 +/- 8.51 (95% CI 87.25-121). The RNFL was thickest in the inferior quadrant, followed by the superior quadrant, and progressively less in nasal and temporal quadrant. The difference between inferior and superior quadrants was not statistically significant. Age had a significant negative correlation with average RNFL thickness (r = -0.321, P = 0.000) and with average superior (r = -0.233, P = 0.005) and average inferior RNFL thickness (r = -0.234, P = 0.004). There was no effect of gender on various RNFL thickness parameters. CONCLUSIONS: RNFL thickness is significantly correlated with age, but not with gender. This normative database of RNFL thickness with OCT in Indian eyes is similar to previously reported values in normal Asian eyes.     

Correlation between retinal nerve fibre layer thickness and retinal sensitivity

Purpose: To evaluate the relationship between retinal nerve fibre layer (RNFL) thickness measured by optical coherence tomography (OCT) and light threshold values obtained with the Micro Perimeter 1 (MP1). Methods: Forty‐nine normal subjects and 37 glaucoma patients were included. Thickness of the RNFL around the optic disc was measured with Stratus OCT scans, and static threshold perimetry was performed with the MP1 at the same visit. Total average and mean 12‐clock‐hour RNFL thickness were measured with Stratus OCT. An automated 4‐2‐1 staircase strategy with Goldmann III stimuli was used for MP1. The correspondence between Stratus OCT and MP1 RNFL measurements in each clock‐hour was best fit by a second‐order polynomial. Results: Average RNFL thickness in the normal group was significantly higher than that in the glaucoma group in each clock hour. Comparing the normal and glaucomatous groups, retinal sensitivity differed significantly at 6, 7, 8 and 11 o’clock. In these regions, structure–function relationships were generally stronger than in other regions. Conclusions: Structure–function associations may be strong when loss of nerve fibres is severe. However, significant reduction in retinal sensitivity does not emerge until the atrophy of nerve fibres is severe.     

Optic disc rim area to retinal nerve fiber layer thickness correlation: comparison of diabetic and normal tension glaucoma eyes

Purpose

To compare the correlation between optic disc rim area and retinal nerve fiber layer thickness (rim-RNFL correlation) in diabetic eyes with non-progressive RNFL defects and normal tension glaucoma (NTG) eyes.

Methods

Seventy-three eyes of 73 patients with preperimetric or early NTG and 25 eyes of 25 type II diabetes patients with a non-progressive RNFL defect for ≥5 years were enrolled in this retrospective cohort study. Rim areas and RNFL thicknesses were measured by Heidelberg retina tomography (HRT II) and by optical coherence tomography (Cirrus OCT), in global and 12 clock-hour parameters. Diabetic eyes were evaluated whether they were above the 95 % prediction interval (PI) for the rim-RNFL correlation of NTG.

Results

A significant linear rim-RNFL correlation was observed in NTG eyes globally and at all clock-hours, except in the 4 and 9 o’clock areas, (0.08 < r ² < 0.56, P < 0.05). Eighty-four percent of the diabetic eyes were above the 95 % PI of the rim-RNFL correlation of NTG in ≥2 clock-hours, as compared with 36 % of the eyes in the global parameter.

Conclusions

The eyes of diabetic patients with non-progressive RNFL were well-differentiated from NTG eyes by the rim-RNFL correlation.     

Longitudinal nerve fibre layer thickness change in normal-pressure glaucoma

Purpose: To investigate longitudinal retinal nerve fibre layer (RNFL) thickness change in patients with normal-pressure glaucoma (NPG) and to assess how this may be related to visual fields. Methods: NPG patients and normal subjects who had had serial GDx nerve fibre layer Analyzer II imaging and Humphrey visual fields performed at least 18 months apart were selected for study. These measurements were compared between groups at baseline and at subsequent follow-up, for change over time. Results: Seventy-five NPG patients and 35 normal subjects were studied. Significant differences in RNFL thickness were found between NPG patients and normal controls at baseline (P≤0.001). Over the same time, there was greater RNFL thinning in NPG patients than in normal subjects (P≤0.0001). RNFL thinning in NPG was negatively correlated with visual field log MD at baseline (P<0.001) and change in MD over time (P<0.001). Conclusion: Reduction of RNFL thickness over time was significantly greater in NPG patients than in normal subjects, indicating that NPG patients’ RNFL had thinned at a faster rate. NPG patients with initially better visual fields had a greater reduction in RNFL thickness than did those with initially more advanced visual field defects, suggesting that more RNFL change may be observed when glaucoma is at an earlier stage. There was a direct relationship between RNFL thinning and visual field deterioration. Received: 15 February 2000 Revised: 27 June 2000 Accepted: 3 July 2000     

Evaluation of retinal nerve fiber layer thickness in the area of apparently normal hemifield in glaucomatous eyes with optical coherence tomography

PURPOSE: The authors investigated the correlation between visual field defects detected by automated perimetry and the thickness of the retinal nerve fiber layer measured with optical coherence tomography, and examined whether there is a decrease in retinal nerve fiber layer thickness in the apparently normal hemifield of glaucomatous eyes. PATIENTS AND METHODS: Forty-one patients with glaucoma and 41 normal control subjects were included in this study. Statistical correlations between the sum of the total deviation of 37 stimuli of each hemifield and the ratio of decrease in retinal nerve fiber layer thickness were evaluated. The statistical difference between the retinal nerve fiber layer thickness of the apparently normal hemifield in glaucomatous eyes and that of the corresponding hemifield in normal subjects was also evaluated. RESULTS: There was a statistically significant correlation in the sum of the total deviation and retinal nerve fiber layer thickness decrease ratio (superior hemifield, P = 0.001; inferior hemifield, P = 0.003). There was no significant decrease in retinal nerve fiber layer thickness in the area that corresponded to the normal visual field in the hemifield defect with respect to the horizontal meridian in glaucomatous eyes (superior side, P = 0.148; inferior side, P = 0.341). CONCLUSIONS: Optical coherence tomography was capable of demonstrating and measuring retinal nerve fiber layer abnormalities. No changes in the retinal nerve fiber layer thickness of the apparently normal hemifield were observed in glaucomatous eyes.     

Comparison of retinal nerve fibre layer thickness and visual field loss between different glaucoma groups

BACKGROUND/AIMS: Scanning laser polarimetry (SLP) uses a confocal scanning laser ophthalmoscope with an integrated polarimeter to evaluate the thickness of the retinal nerve fibre layer (RNFL). The aim of this study was to verify the ability of the SLP to detect differences in RNFL thickness between normal and glaucomatous eyes and between glaucomatous eyes subdivided in groups by the severity of visual field damage. METHODS: This was a cross sectional retrospective study. The charts of 40 healthy subjects and 68 glaucoma patients who underwent complete ophthalmological examination, optic disc stereophotography, peripapillary, and macular SLP imaging were reviewed. The right eye of subjects eligible for the study was enrolled. Only eyes with SLP examinations indicating a minimised effect of anterior segment birefringence based on macular image were included. The ability of retardation parameters to discriminate between healthy and glaucomatous eyes was evaluated. Based on visual field loss, glaucoma patients were subdivided in three subgroups (early, moderate, and severe). RNFL thickness between healthy control group and glaucoma subgroups was compared. RNFL thickness and visual field loss correlation was evaluated. RESULTS: There was a significant difference in superior and inferior maximum RNFL thickness between normal and glaucomatous eyes (p<0.001). With these two parameters, the area under receiver operator characteristic curve was 0.75 and 0.74, respectively. Superior and inferior RNFL thickness was significantly different between healthy control group and all glaucoma subgroups (p<0.001) and between glaucoma subgroups (p<0.05), except for early and moderate glaucoma subgroups (p>0.05). Linear regression showed a weak correlation between RNFL thickness and visual field loss. CONCLUSION: These results suggest that once visual field loss is established, smaller reductions in the RNFL thickness detected by SLP are necessary for a given reduction of mean defect value.     

Relationship between central corneal thickness and localized retinal nerve fiber layer defect in normal-tension glaucoma

PURPOSE: To determine whether central corneal thickness (CCT) is related to the extent of localized retinal nerve fiber layer (RNFL) defect at the initial examination of normal-tension glaucoma (NTG) patients. PATIENTS AND METHODS: Seventy-five eyes of 75 NTG patients showing localized RNFL defects on RNFL photographs and corresponding visual field defects at the initial visit to a glaucoma specialist were selected for this study. All participants completed refraction, Goldmann applanation tonometry, CCT measurement, stereoscopic disc photography, RNFL photography, and automated perimetry. Each patient's age, spherical equivalent, intraocular pressure, CCT, approximation of the RNFL defect to the fovea (angle alpha), circumferential width of the RNFL defects (angle beta), horizontal and vertical cup-to-disc ratios, and mean deviation of visual field were analyzed. RESULTS: In univariate and multivariate analyses, lower CCT was significantly associated with increased horizontal and vertical cup-to-disc ratios, decreased angle alpha, and increased angle beta. For a decrease of 10 microm of CCT, horizontal and vertical cup-to-disc ratios increased by 0.020, angle alpha decreased by 1.58 degrees, and angle beta increased by 1.71 degrees, respectively. CONCLUSION: CCT is a significant factor in predicting the extent of localized RNFL defect at the initial examination of NTG patients.     

慢性闭角型青光眼未发病眼视网膜神经纤维层的厚度

目的:采用偏振激光扫描仪(GDxVCC系统)检测正常眼、慢性闭角型青光眼(chronicangle-closureglaucoma,CACG)有明显视野缺损的患眼及其视野未受损害的另眼(未发病眼)的视网膜神经纤维层(retinalnervefiberlayer,RNFL)厚度,并进行比较,了解未发病眼RNFL厚度变化有无改变,探讨GDxVCC系统在慢性闭角型青光眼早期诊断中的价值。方法:前瞻性对照研究。慢性闭角型青光眼患者26例,1眼具有可重复性视野缺损,其另眼视野检查正常(如:差异概率图上≤1个测试点在5%概率水平以下),将视野正常的未发病眼定为CACG-视野正常组,有视野缺损的已确诊眼为CACG-视野缺损组;24例48眼年龄相匹配的正常人作为对照组。所有入选对象进行视野和GDxVCC系统检查。采用方差分析,对CACG-视野正常组、CACG-视野缺损组、正常对照组的RNFL参数进行两两比较GDxVCC检测RNFL厚度。结果:与正常对照组相比,CACG患者视野未受损组眼的视网膜神经纤维层变薄。但视野未受损眼的RNFL明显厚于视野缺损眼。3组的各RNFL参数差异均有显著统计学意义;CACG—视野正常组与正常对照组间下方平均值和神经纤维指数(P=0.073,P=0.054)差异无显著统计学意义,但其椭圆平均值、上方平均值及TSNIT标准差与正常对照组相比有极显著统计学意义(P=0.002,P=0.002,P=0.010)。结论:GDxVCC系统可以更早地检测出CACG未发病眼RNFL结构损害,对临床处理早期CACG具有指导意义。     

Macular and peripapillary retinal nerve fibre layer thickness in adults with amblyopia

Objective

To evaluate macular and peripapillary retinal nerve fiber layer (RNFL) thickness in amblyopic eyes compared to the fellow eye.

Design

Cross-sectional study.

Participants

30 patients (60 eyes) older than 18 years of age with amblyopia.

Methods

Inclusion criteria included individuals older than 18 years, amblyopia, and best-corrected visual acuity (BCVA) ≤20/40. A complete medical history was taken and an eye examination carried out. Optical coherence tomography (OCT) was carried out on both eyes of all patients. Exclusion criteria included intraocular pressure (IOP) >23 mm Hg and eye pathology that may affect OCT measurements. The primary outcome measures were foveal thickness and average peripapillary RNFL thickness, which were compared using a paired t test. Quadrants in peripapillary scans and concentric rings in macular scans were analyzed.

Results

The average age was 56 years (range = 33–82 years). Visual acuity ranged from 20/40 to 20/4000 (mean = 20/275). The average peripapillary RNFL thickness was 90.6 μm (SD = 9.6 μm) in the amblyopic eye and 90.1 μm (SD = 12.1 μm) in the fellow eye (p = 0.64). The average macular thickness in amblyopic eyes was 260.1 μm (SD = 32.0 μm), and 254.7 μm (SD = 32.5 μm) in fellow eyes (p = 0.10). No statistical difference existed between peripapillary quadrants or macular concentric rings. These differences were smaller when the strabismic amblyopes were isolated.

Conclusions

There does not seem to be a difference in peripapillary RNFL or macular thickness between the amblyopic eye and fellow eye.     

Comparison of ganglion cell and retinal nerve fiber layer thickness in primary open-angle glaucoma and normal tension glaucoma with spectral-domain OCT

Background

The aim of this study was to evaluate the macular thickness (MT), ganglion cell complex (GCC), and circum-papillary retinal nerve fiber layer (RNFL) thickness in primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG) with spectral domain optical coherence tomography (SD-OCT).

Methods

A total of 169 subjects were enrolled: 52 normal subjects, 61 with POAG, and 56 with NTG. Spectral-domain optical coherence tomography (SD-OCT) was used to analyze MT, GCC, and RNFL thickness. To compare the discrimination capabilities between the MT, GCC, and RNFL thickness measurements, we analyzed the areas under the receiver operating characteristic (ROC) curves (AUCs). The relationships between GCC and RNFL measurement and also the relationships of the groups, with age, gender, GCC, and RNFL thickness were assessed.

Results

Normal subjects showed the thickest superior and inferior GCC, followed by in order NTG and POAG (p?<?0.05). While there was a statistically difference in MT value of the normal subjects and the glaucoma patients (p?<?0.05), MT value did not differ between POAG and NTG (p?<?0.05). RNFL thickness parameters were significantly greater in normal subjects, followed in order by the NTG, and POAG (p?<?0.05). Between the normal and entire glaucoma groups, all GCC and RNFL parameters showed the similar discrimination power. RNFL thickness parameters correlated significantly with all GCC thickness (p?<?0.05). Superior RNFL thickness was the only independent variable between the POAG and NTG patients (odds ratio (OR) 0.942, p?=?0.004, 95 %CI 0.905–0.981).

Conclusions

SD-OCT evaluation results suggest higher GCC and RNFL parameters for NTG than POAG.     

Retinal nerve fiber layer thickness in the fellow eyes of normal-tension glaucoma patients with unilateral visual field defect

PURPOSE: To quantitatively evaluate retinal nerve fiber layer (RNFL) thickness in the fellow eyes of normal-tension glaucoma (NTG) patients with unilateral visual field defect. DESIGN: Observational case-control study. METHODS: Twenty-nine NTG patients with unilateral visual field defect were enrolled in this study. All 29 fellow eyes showed normal visual field. Thirty-one normal eyes of 31 subjects served as controls. The RNFL thickness around the optic disk was determined using Fast RNFL thickness (3.4) of optical coherence tomography. Average and segmental (4 quadrants and 12 clock- hours) RNFL thickness measurements were compared among the three groups. RESULTS: RNFL thicknesses were significantly different among the three groups in the average, superior quadrant (11 and 12 clock-hour segments), and inferior quadrant (6 clock-hour segment) (P = .00, one-way ANOVA and Tukey's tests). CONCLUSIONS: RNFL thickness reductions are already present in the fellow eyes of NTG patients with unilateral visual field defect.     

Peripapillary retinal nerve fibre layer thickness measurement with SD-OCT in normal and glaucomatous eyes:distribution and correlation with age

AIM:To determine peripapillary retinal fiber layer thickness (RNFL) measured with spectral domain optical coherence tomography (SD-OCT) in normal and glaucomatous eyes in a large sample of exclusively white population and compare results with other similarly constructed studies.METHODS:Average, maximum, minimum and per quadrant RNFL thickness were measured in normal and glaucomatous Greek patients with a scanning laser ophthalmoscope (SLO)/SD-OCT device. The effect of age in normal RNFL thickness was also determined.RESULTS: A total of 278 normal (278 patients) and 67 glaucomatous (67 patients) eyes were included in the study. Average RNFL thickness was 114.8±13.3μm in normal and 92.1±18.5μm in glaucomatous eyes (P<0.001). In normal discs, superior quadrant was the thickest, followed by the inferior, nasal and temporal. Decline of normal RNFL thickness with age was statistically significant for average RNFL thickness (1.92μm per decade of life) and for the superior and inferior quadrants of the disc.CONCLUSION:SD-OCT peripapillary RNFL measurements can be used to distinguish between normal and glaucomatous eyes and establish normative databases, since normal disc measurements differ between different ethnic groups and between different SD-OCT devices.