Search

Purpose: To compare the reproducibility of annulus area measurements of the circumpapillary retinal nerve fiber layer thickness (cpRNFLTannulus) using spectral-domain optical coherence tomography (SD-OCT) with that of conventional cpRNFLT (cpRNFLTring) measurements and evaluate the effect of correction of ocular rotation on the reproducibility., Materials and Methods: Peripapillary SD-OCT raster scans were performed on 2 different days in 48 normal subjects and 59 patients with glaucoma using the Topcon OCT-1000. In the raster scan dataset, the cpRNFLTring and cpRNFLTannulus were averaged along a circle (3.4-mm diameter) and in an annulus area (diameters from 2.8 to 4.0 mm) centered on the barycenter of the disc. The measurement reproducibility, effects of ocular rotational correction, and factors affecting the reproducibility were studied., Results: The intervisit reproducibility values, expressed as the coefficients of variation, for the cpRNFLTannulus, were significantly smaller than those for the cpRNFLTring measurements in sectors 30 degrees wide in glaucomatous eyes (P=0.006) and in sectors 10 degrees wide in normal and glaucomatous eyes (P<0.001). The ocular rotational angles averaged 7.1 and 7.2 degrees with intervisit differences of 1.4 and 1.8 degrees, respectively, in normal and glaucomatous eyes. Correction for the ocular rotation had little effect on the reproducibility. The mean deviation and cpRNFLT were correlated negatively with the coefficient of variation (β=-0.93 to -0.83; P=0.027 to 0.028)., Conclusions: The cpRNFLTannulus measurement yielded better reproducibility than the cpRNFLTring measurement, and multiple linear regression analysis showed that the more advanced the glaucomatous damage, the worse the intervisit reproducibility.

Purpose: To evaluate grid-wise analyses of macular inner retinal layer thicknesses and effect of compensation of disc-fovea inclination for diagnosing early-stage glaucoma., Methods: Spectral-domain optical coherence tomography measurements over a 6.0 × 6.0-mm macular area were prospectively obtained in 104 eyes of 104 patients with early-stage glaucoma with a mean deviation of -1.8 ± 1.9 dB and 104 eyes of 104 age- and refraction-matched normal subjects. Macular retinal nerve fiber layer (mRNFL), ganglion cell-inner plexiform layer (GCIPL) combined, and ganglion cell complex (GCC) thickness of the entire area and each subdivided macular grid were determined to compare diagnostic capability for glaucoma using receiver operating characteristic curves and various normal cutoff values for each layer thickness and number of grids flagged as abnormal. Diagnostic capability was then compared with that of circumpapillary RNFL (cpRNFL) measurements. Effects of compensation of inclination of disc-fovea line by reconfiguration of the macular grid were also studied., Results: Macular inner retinal layer analyses using 8 × 8 grids generally yielded higher diagnostic capability. Only the 8 × 8 grid GCC analyses using the various normal cutoff values yielded a sensitivity ≥ 0.90 with specificity ≥ 0.95 under several conditions in discriminating the glaucoma eyes. In glaucoma and normal eyes with both reliable cpRNFL and macular measurements, the best sensitivity/specificity were 0.98/0.95 for the 8 × 8 grid-mRNFL analysis and 0.93/0.96 for the 8 × 8 grid GCC analysis using various normal cutoff values, which were better than that (0.78/0.95) for clock-hour cpRNFL analysis (P = 0.001). Compensation of the disc-fovea inclination did not improve the diagnostic capability., Conclusions: Grid-wise analysis of macular GCC--especially using 8 × 8 grids and normative data-based cutoff values--was very useful for diagnosing early-stage glaucoma, though compensation of the disc-fovea inclination had little effect.

Purpose: To diagnose glaucoma based on spectral domain optical coherence tomography (SD-OCT) measurements using the 'Random Forests' method., Methods: SD-OCT was conducted in 126 eyes of 126 open angle glaucoma (OAG) patients and 84 eyes of 84 normal subjects. The Random Forests method was then applied to discriminate between glaucoma and normal eyes using 151 OCT parameters including thickness measurements of circumpapillary retinal nerve fiber layer (cpRNFL), the macular RNFL (mRNFL) and the ganglion cell layer-inner plexiform layer combined (GCIPL). The area under the receiver operating characteristic curve (AROC) was calculated using the Random Forests method adopting leave-one-out cross validation. For comparison, AROCs were calculated based on each one of the 151 OCT parameters., Results: The AROC obtained with the Random Forests method was 98.5% [95% Confidence interval (CI): 97.1-99.9%], which was significantly larger than the AROCs derived from any single OCT parameter (maxima were: 92.8 [CI: 89.4-96.2] %, 94.3 [CI: 91.1-97.6] % and 91.8 [CI: 88.2-95.4] % for cpRNFL-, mRNFL- and GCIPL-related parameters, respectively; P<0.05, DeLong's method with Holm's correction for multiple comparisons). The partial AROC above specificity of 80%, for the Random Forests method was equal to 18.5 [CI: 16.8-19.6] %, which was also significantly larger than the AROCs of any single OCT parameter (P<0.05, Bootstrap method with Holm's correction for multiple comparisons)., Conclusions: The Random Forests method, analyzing multiple SD-OCT parameters concurrently, significantly improves the diagnosis of glaucoma compared with using any single SD-OCT measurement.

Purpose: To study diagnostic performances of circle- and grid-wise analyses of peripapillary retinal nerve fiber layer thickness (RNFLT) using spectral domain optical coherence tomography (SD-OCT) in early-stage glaucoma., Methods: Eighty-nine open-angle glaucoma (OAG) eyes (mean deviation: 2.5 ± 1.8 dB) and 89 age-matched normal eyes were studied. Peripapillary RNFLT was analyzed using an SD-OCT raster scan in a 6.0 × 6.0-mm area. Averaged RNFLT was calculated over 0.1 × 0.1-, 0.21 × 0.21-, or 0.42 × 0.42-mm grids in the peripapillary area (grid method), or arcuate sector areas between 2.8- and 4.0-mm diameter circles (annulus method), or along a 3.4-mm diameter circle (circle method). Normative data-based cutoff values for averaged RNFLT and number of abnormal grid locations (grid method) or sectors (annulus or circle method) were varied., Results: The grid method showed the best power of sensitivity/specificity of 0.94/0.96 with any five contiguous 0.21 × 0.21-mm grid locations with a 2.5 percentile cutoff, followed by the annulus method of 0.81/0.98, and the circle method of 0.76/0.97, with 30° sectors. The sensitivity of the grid method was significantly higher than that of the other methods (P < 0.001), whereas the specificity was not. Coefficients of variation and interclass correlation coefficients of intervisit measurements of averaged RNFLT over each 0.21 × 0.21-mm grid were 3.1% to 11.3% and 0.937 to 0.760, respectively, in a separate OAG patient group., Conclusions: Grid-wise analyses of peripapillary RNFLT for differentiating early-stage glaucoma showed >0.90 sensitivity and ≥0.95 specificity.

Purpose: To evaluate the intervisit reproducibility of spectral-domain optical coherence tomography (SD-OCT) measurement of the macular retinal nerve fiber layer thickness (mRNFLT); combined ganglion cell layer and inner plexiform layer (GCL+IPL) thickness; and ganglion cell complex (GCC) thicknesses (sum of mRNFLT and GCL+IPL thicknesses) compared with that of circumpapillary RNFLT (cpRNFLT) and the effect of ocular rotation on reproducibility., Methods: SD-OCT imaging was performed twice on different days in one eye of 58 normal subjects and 73 glaucoma patients. The reproducibility was evaluated for the entire 4.8-mm × 4.8-mm macular area and subareas (upper and lower halves, 2 × 2, 4 × 4, and 8 × 8 grids), and the 360°, upper, and lower halves mean cpRNFLT with and without correction of ocular rotation., Results: The coefficients of variation (CVs) of GCL+IPL and GCC thickness measurements averaged below 1.0% for the entire and upper and lower half macular areas, and below 4.2% in the macular subareas in normal and glaucoma eyes, which were significantly smaller (P < 0.001) than those of mRNFLT measurements in the same areas of the same eyes. The CVs of mRNFLT measurements were significantly smaller than those of the cpRNFLT only in the lower half mean area in normal eyes. The reproducibility was minimally affected by correction of ocular rotation or presence of glaucoma., Conclusions: The reproducibility of the macular (GCL+IPL) and GCC thickness measurements was better than that of mRFNLT and cpRNFLT in normal and glaucoma eyes and minimally affected by correction of ocular rotation.

Objectives: To evaluate the peripapillary distribution of retinal nerve fiber layer thickness (RNFLT) in normal eyes using spectral-domain optical coherence tomography and to study potentially related factors., Methods: In 7 institutes in Japan, RNFLT in 7 concentric peripapillary circles with diameters ranging from 2.2 to 4.0 mm were measured using spectral-domain optical coherence tomography in 251 ophthalmologically normal subjects. Multiple regression analysis for the association of RNFLT with sex, age, axial length, and disc area was performed., Results: Retinal nerve fiber layer thickness decreased linearly from 125 to 89 μm as the measurement diameter increased (P < .001, mixed linear model). Retinal nerve fiber layer thickness correlated with age in all diameters (partial correlation coefficient [PCC] = -0.40 to -0.32; P < .001) and negatively correlated with disc area in the 2 innermost circles but positively correlated in the 3 outermost circles (PCC = -0.30 to -0.22 and 0.17 to 0.20; P ≤ .005). Sex and axial length did not correlate with RNFLT (P > .08). The decay slope was smallest in the temporal and largest in the nasal and inferior quadrants (P < .001); positively correlated with disc area (PCC = 0.13 to 0.51; P ≤ .04); and negatively correlated with RNFLT (PCC = -0.51 to -0.15; P ≤ .01)., Conclusions: In normal Japanese eyes, RNFLT significantly correlated with age and disc area, but not with sex or axial length. Retinal nerve fiber layer thickness decreased linearly as the measurement diameter increased. The decay slope of RNFLT was steepest in the nasal and inferior quadrants and steeper in eyes with increased RNFLT or smaller optic discs.