Shinsuke Konno

Peripapillary Retinal Nerve Fiber Layer Thickness Determined by Spectral-Domain Optical Coherence Tomography in Ophthalmologically Normal Eyes

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.

Cross-sectional Anatomic Configurations of Peripapillary Atrophy Evaluated with Spectral Domain-Optical Coherence Tomography

PURPOSE To evaluate the cross-sectional configurations of peripapillary atrophy (PPA)-alpha and -beta in ophthalmologically normal subjects using spectral domain-optical coherence tomography (SD-OCT). METHODS One hundred twenty normal subjects had a complete ophthalmic examination including axial length measurement, standard automated perimetry, fundus imaging with photography, and SD-OCT (3D OCT-1000; Topcon Inc., Tokyo, Japan). PPA-alpha and -beta were identified in color photographs of the optic disc. Cross-sectional B-mode images of the peripapillary retina and sclera, including PPA-alpha and -beta obtained with SD-OCT, were analyzed. RESULTS Of 120 normal eyes, 120 (100%) had PPA-alpha and 90 (75%) had PPA-beta. In OCT images of the peripapillary retina, the ganglion cell layer and the inner and outer plexiform layers were observed to end in a tapering fashion at the edge of the optic disc, whereas the retinal nerve fiber layer continued into the optic cup. The external limiting membrane (ELM), inner-outer segments (IS-OS), and retinal pigment epithelium(RPE)/Bruchs membrane complex were significantly more commonly absent before the optic disc edge within the PPA-beta compared with areas outside the PPA-beta (P < 0.0001). Specific findings in the peripapillary area including slope and step configurations of the scleral bed and hump- and wedge-shaped appearances of the RPE-Bruchs membrane complex were identified in 63 (52.5%), 6 (5.0%), 19 (15.8%), and 6 (5.0%) of 120 eyes, respectively. The presence of the step configuration was associated with myopia and longer axial length (P = 0.0014 and 0.0105, respectively). CONCLUSIONS The cross-sectional anatomic configurations of the peripapillary atrophy were evaluated by using SD-OCT. The termination of the retinal layers and configurations of the scleral bed in the peripapillary area varied among normal subjects.

Spectral-Domain Optical Coherence Tomography ofβ-zone Peripapillary Atrophy: Influence of Myopiaand Glaucoma

PURPOSE To investigate the influence of glaucoma and myopia on the cross-sectional configuration of the β-zone of peripapillary atrophy (PPA-β) using spectral-domain optical coherence tomography (SD-OCT). METHODS Cross-sectional B-scan images of PPA-β obtained with SD-OCT were evaluated in 100 eyes of 100 consecutive patients with POAG, regardless of intraocular pressure level, and in 100 eyes of 100 normal subjects. PPA bed configurations were classified, and associated factors were studied with multivariate analysis. RESULTS In 147 eyes with PPA-β (84 POAG and 63 normal eyes; P = 0.0012), the PPA bed was composed of straight (14 POAG and 27 normal eyes) or downward-curved (19 and 8 eyes) Bruchs membrane (BM) or of a downward-bending slope lacking BM (BM defect; 51 and 28 eyes). Multivariate analysis revealed that absence of POAG (odds ratio [OR], 0.36; P = 0.034) and less myopic refractive error (OR, 1.43; P = 0.009) were significantly associated with straight-BM-type, presence of POAG (OR, 5.74; P = 0.008) and less myopic refractive error (OR, 3.02; P < 0.001) with curved-BM-type, and myopic refractive error (OR, 0.34; P < 0.001) with BM-defect-type. Within the PPA-β region, all retinal layers except for the nerve fiber layer frequently disappeared before reaching the disc edge, showing no significant intergroup difference (P > 0.05) between POAG and normal eyes. CONCLUSIONS PPA bed configurations detected by SD-OCT were classified into three types. The lack of BM on the PPA bed was closely associated with myopia. The downward-curved appearance of BM may be related to the anatomic changes associated with glaucoma.

Evaluation of optic nerve head configurations of superior segmental optic hypoplasia by spectral-domain optical coherence tomography

Aims To characterise the optic nerve head (ONH) configurations of superior segmental optic hypoplasia (SSOH) using a spectral-domain optical coherence tomography (SD-OCT). Methods Horizontal cross-sectional images of the ONH were obtained by a SD-OCT in 20 eyes of 14 patients with clinically typical SSOH and 20 age- and refraction-matched normal eyes. Results Extension of retinal pigment epithelium (RPE) over the disc margin was observed in 20 eyes (100%) with SSOH and eight (40%) control eyes (p<0.001). The maximum length of the overhanging RPE measured at the nasal disc margin was significantly longer in eyes with SSOH than in controls (295.9±112.6 vs 24.3±33.9 μm; p<0.0001). In eyes with SSOH, the retinal nerve fibre layer (RNFL) was significantly thinner in the temporal-superior to nasal sectors (p<0.01). Conclusions The extension of RPE over the nasal disc margin was more common and longer in eyes with SSOH than in normal eyes, suggesting that the SD-OCT findings might facilitate the diagnosis of SSOH. Substantial thinning of the RNFL was present in wider areas than previously expected in SSOH.

Circle- and Grid-Wise Analyses of Peripapillary Nerve Fiber Layers by Spectral Domain Optical Coherence Tomography in Early-Stage Glaucoma

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.

Correlation of Macular Ganglion Cell Complex Thickness With Frequency-doubling Technology Perimetry in Open-angle Glaucoma With Hemifield Defects.

Purpose:To understand better the relationship between the macular ganglion cell complex (mGCC) thickness and visual field sensitivity assessed by frequency-doubling technology (FDT) perimetry in the standard automated perimetry (SAP) normal hemifields of glaucomatous eyes, a model of preperimetric stage of glaucoma. Patients and Methods:Thirty-four eyes of 34 patients with glaucomatous visual field defects restricted to the superior or inferior hemifield were included. Patients underwent the mGCC and circumpapillary retinal nerve fiber layer (cpRNFL) thickness measurements using spectral domain optical coherence tomography and the FDT testing with N-30 full-threshold protocol. SAP and FDT sensitivity values were averaged in the area corresponding to thickness measurements and the thickness sensitivity relationships were assessed in the SAP normal and SAP abnormal halves (Spearman’s rank correlation coefficient). Results:FDT sensitivity was significantly correlated with both the cpRNFL and mGCC thicknesses either in the SAP normal (&rgr;=0.384 and 0.462, respectively) or in the SAP abnormal (&rgr;=0.402 and 0.717, respectively) halves. Correlation between the FDT sensitivity and the mGCC thickness was significantly (P=0.016) stronger than that with the cpRNFL thickness in the SAP abnormal half. SAP sensitivity was correlated significantly (&rgr;=0.570) only with the mGCC thickness in the SAP abnormal half. Conclusions:Similarly strong correlations of the mGCC thickness with the FDT sensitivity in the SAP normal and SAP abnormal halves, but not with the SAP sensitivity, indicates that the mGCC thickness and the FDT sensitivity may be more optimal structure-function indicator in preperimetric stage of glaucoma.