Parapapillary Retinal Nerve Fiber Layer Research Articles

Optical coherence tomography findings in children of patients with Alzheimer-type dementia

BackgroundOcular imaging receives much attention as a source of potential biomarkers for dementia. This study aims to study structural changes in the retina and optic nerve in children of healthy and demented parents and to confirm the applicability of optic nerve tomography as a potential noninvasive marker for the early diagnosis of dementia.MethodsHealthy individuals with a parent diagnosed with Alzheimer’s disease (AD) and healthy controls with healthy parents were included in the study. Included individuals had undergone Montreal Cognitive Assessment Scale and Mini-Mental Test by a single neurologist physician to confirm not having dementia. All the subjects then underwent a complete ophthalmological examination, including refractive error and keratometry readings, best-corrected visual acuity measurement with a Snellen chart (converted to LogMAR), intraocular pressure (IOP) measurement, slit-lamp biomicroscopy, dilated fundus examination, axial length measurement and optical coherence tomography (OCT) for the parapapillary retinal nerve fiber layer (pRNFL), basal membrane opening—minimum rim width (BMO-MRW), and macular thickness analysis. Only the right eyes of the subjects were evaluated. OCT findings of these two groups were compared.ResultsThe temporosuperior sector the pRNFL thicknesses at all 3 circles (3.5, 4.1, and 4.5) were significantly thinner in the children of the dementia group than in healthy controls (p = 0.023, 0.039, and 0.016, respectively). For the remaining sectors, the thicknesses of the pRNFL were also thinner, however, the differences were not significant (p > 0.05 for all). BMO-MRW at all sectors, were not also different significantly between the groups (p > 0.05 for all). Parents’ dementia grade were found to be an important factor that the BMO-MRW at the temporal sector, got thinner with increasing grade (B = − 20.631, 95% CI − 42.121 to − 0.019, and p = 0.049).ConclusionWe believe that OCT can be used as a noninvasive biomarker in the preclinical period, when supported by more extensive studies in people whose parents have AD.

The Topographic Relationship Between Choroidal Microvascular Dropout and Glaucomatous Damage in Primary Angle-Closure Glaucoma.

PurposeTo study the topographic relationship between parapapillary choroidal microvasculature dropout (MvD) and parapapillary retinal nerve fiber layer (RNFL) defect in primary angle-closure glaucoma (PACG) eyes.MethodsThis cross-sectional study was carried out in a glaucoma clinic. Patients with PACG and healthy controls were consecutively enrolled. Each subject underwent optical coherence tomography angiography (OCTA) and OCT testing; additionally, visual field (VF) tests were also conducted in the patients with PACG. MvD was determined when choroidal layer images in OCTA showed a complete loss of the microvasculature. The study included 55 patients with PACG and 30 healthy controls.ResultsFifty-five eyes in 55 patients with PACG and 30 eyes in 30 healthy controls were recruited. MvD was found in 26 PACG eyes (47.3%), but no MvD was found in the healthy eyes. Compared with PACG eyes without MvD, eyes with MvD had thinner average RNFL (P < 0.001), worse VF mean deviation (P = 0.006), and lower peripapillary vessel density (P < 0.001). Between MvD and RNFL defects, there was good topographic consistency in angular circumference (Bland–Altman 95% confidence interval [CI], −24.9° to 21.0°) and position (Bland-Altman 95% CI, −18.6° to 20.6°). There was a significant correlation between the MvD angular circumference and the average peripapillary vessel density (r = −0.505; P = 0.014), average RNFL thickness (r = −0.742; P < 0.001), and VF mean deviation (r = −0.572; P = 0.004).ConclusionsIn patients with PACG, the MvD angular circumference and position were highly topographic consistent with those of the peripapillary RNFL defect area. This study suggests that there is a significant correlation between MvD and glaucoma optic nerve injury.Translational RelevanceGiven the vascular etiology for glaucoma, the current research suggests that the MvD angular circumference may serve as a potential supplementary clue of glaucoma disease severity.

Retinal nerve fibre layer thickness measured with SD-OCT in a population-based study: the Handan Eye Study

PurposeTo examine the normative profile of retinal nerve fibre layer (RNFL) thickness and ocular parameters based on spectral-domain optical coherence tomography (SD-OCT) and its associations with related parameters among the...

Controlled diabetes amends oxidative stress as mechanism related to severity of diabetic retinopathy

Oxidative stress is a well-accepted etiological mechanism that contributes to neuronal dysfunction. Role of oxidative stress as a mechanism of retinopathy in controlled type 2 diabetic patients was evaluated. Participants were divided into three groups: Group 1 as 30 normal eyes of 15 subjects, Group 2 comprised 24 eyes of 12 diabetic patients without retinopathy and Group 3 comprised 23 eyes of 12 diabetic patients with different grades of retinopathy (8 eyes with maculopathy). A complete ophthalmological examination was performed. Oxidative stress markers were measured in blood. Macular thickness was different in all quadrants among all groups and showed a tendency to increase in Group 3 due to diabetic retinopathy with insignificant changes in parapapillary retinal nerve fiber layer thickness although thinning was noted also with retinopathy. Non-significant differences in GST and lipid peroxide levels were observed between the three studied groups, whereas vitamin C and GSH levels were higher in diabetic patients when compared to those in controls. As oxidative stress, hyperglycemia and local inflammation are involved in the pathogenesis of DR, the present study proved that the progressive damage can be retarded in controlled type 2 diabetic patients using different treatment modalities that abated oxidative stress.

A Meta-Analysis of Alterations in the Retina and Choroid in High Myopia Assessed by Optical Coherence Tomography Angiography

Background: High myopia (HM) is a risk factor for several pathological structural changes in retinal and choroidal thickness or vessel. To date, changes in retinal and choroidal microvasculature circulations in HM have yielded inconsistent results. Objectives: The objective of this article was to evaluate alterations in retinal and choroidal thickness, and capillary microvasculature using optical coherence tomography angiography (OCTA) in HM. Methods: PubMed, Embase, and the Cochrane Library databases were searched for relevant published studies. Primary outcomes were foveal avascular zone, vessel density, retinal nerve fiber layer (RNFL) thickness, foveal thickness, sub-foveal choroidal thickness, and chorio-capillary density. Alterations in outcomes were evaluated by standardized mean difference with a 95% confidence interval. Results: Eleven eligible articles were included for the meta-analysis. The whole superficial and deep vessel densities of macular and parapapillary superficial vessel density were lower in HM than in control eyes. The thickness of parafoveal RNFL, parapapillary RNFL, and sub-foveal choroid was significantly lower in HM eyes. Also, chorio-capillary density was shown to be lower in HM eyes. Conclusions: The retinal and choroidal vessel network change may be related to the axial elongation in the progression of myopia. Furthermore, OCTA is an effective and noninvasive technology for monitoring the progress of myopia eyes.

Progression of Macular Vessel Density in Primary Open-Angle Glaucoma: A Longitudinal Study

To evaluate the rate of progression of macular vessel density (mVD) in primary open-angle glaucoma (POAG) and explore the relationship between the progression of mVD and macular ganglion cell-inner plexiform layer (mGCIPL) thickness and parapapillary retinal nerve fiber layer (pRNFL) thickness. Prospective cohort study. In this study, 102 eyes with POAG were followed for 36.6 ± 6.4months. The rates of progression were estimated by linear models. The agreement of progression detection among the 3 parameters was evaluated with Kappa statistics. The influence of baseline measurements on the rates of progression of mGCIPL thickness, pRNFL thickness, and mVD was investigated by linear mixed modeling. Kaplan-Meier survival analysis was adopted to calculate the survival probabilities. The respective rate of progression by linear regression was-0.102 ± 0.054μm/month,-0.160 ± 0.086μm/month, and-0.199 ± 0.073 %/month for mGCIPL thickness, pRNFL thickness, and mVD. The agreement in detection of progression among them was poor with the Conger's Kappa coefficient of 0.098 (95% confidence interval:-0.025~0.220, P= .116). The significant factors influencing the rate of progression of mVD were baseline mGCIPL thickness, baseline pRNFL thickness, and baseline mVD (P ≤ .001), while baseline mVD was not a significant factor influencing the rates of progression of mGCIPL thickness and pRNFL thickness (P ≥ .659). Also, pRNFL thickness had a better survival probability compared with the other 2 parameters (P= .025). The mGCIPL thickness, pRNFL thickness, and mVD decreased over time in POAG eyes. The rate of reduction of mVD was significantly influenced by the baseline measurements of mGCIPL thickness, pRNFL thickness, and mVD.

Optical Coherence Tomography Angiography in Glaucoma.

Optical coherence tomography angiography (OCTA) is a relatively new, noninvasive, dye-free imaging modality that provides a qualitative and quantitative assessment of the vasculature in the retina and optic nerve head. OCTA also enables visualization of the choriocapillaris, but only in areas of parapapillary atrophy. With OCTA, the movement of red blood cells is used as a contrast to delineate blood vessels from static tissues. The features seen with OCTA in eyes with glaucoma are reduction in the superficial vessel density in the peripapillary and macular areas, and complete loss of choriocapillaris in localized regions of parapapillary atrophy (called deep-layer microvascular dropout). These OCTA changes correlate well topographically with the functional changes seen on visual field examination and structural changes seen on optical coherence tomography (OCT) (ie, parapapillary retinal nerve fiber layer changes and inner retinal layer thickness changes at macula). The OCTA measurements also have acceptable test-retest variability and well differentiate glaucomatous from normal eyes. OCTA measurements can be affected by various subject-related, eye-related, and disease-related factors. Vessel density reduction on OCTA reaches a base level (floor) at a more advanced disease stage than the structural changes on OCT and therefore has the potential to monitor progression in eyes with advanced glaucomatous damage. OCTA also adds information about glaucoma patients at risk of faster progression. OCTA, therefore, complements visual field and OCT examinations to diagnose glaucoma, detect progression, and assess risk of progression.

The correlation of ganglion cell layer thickness with visual field defect in non-functional pituitary adenoma with chiasm compression

Objective: To investigate the consequences of the thickness of ganglion cell layer (GCL) and visual field defect of non-functional pituitary adenoma with chiasm compression. Methods: A case control study. The study included 40 (80 eyes) non-functional pituitary adenoma patients in Peking Union Medical College Hospital from March 2015 to February 2017. Twenty patients (no visual field defect group, 40 eyes) of them were detected to be chiasm compressed or touched by the adenoma with no visual field defect detected, and the other 20 patients (visual field defect group, 40 eyes) were the sex-and-age matched pituitary adenoma patients with bitemporal heminopsia. This study also included 20 (control group, 40 eyes) sex-and-age matched healthy controls. The para-papillary retinal nerve fiber layer (RNFL) thickness in 6 quadrants including nasal, temporal, nasal superior, temporal superior, nasal inferior and temporal inferior as well as the macular GCL thickness and ganglion cell-inner plexiform layer (GCIPL) thickness in 4 quadrants including nasal superior, nasal inferior, temporal superior and temporal inferior were measured. The non-parametric test was used to compare the RNFL, GCL and GCIPL thickness among the three groups. Results: The mean age among the three groups was (46±10) years and the difference among the three groups was not significant (P=0.88). The sex ratio of the three groups was 9∶11 (male∶female) and the difference among the three groups was not significant. The mean axial length among the three groups was (23.22±0.90) mm and the difference among the three groups was not significant (P=0.51). The thickness of para-papillary RNFL of temporal superior, temporal, nasal superior, nasal, nasal inferior quadrants and whole circumference was significantly thinner in the visual field defect group than the control group [(129.88±28.64) μm, (63.63±26.84) μm, (88.08±32.16) μm, (50.68±19.99) μm, (92.48±25.06) μm, and (85.00±20.65) μm vs. (141.10±18.95) μm, (79.12±16.78) μm, (113.68±21.28) μm, (69.67±14.23) μm, (117.80±31.32) μm, and (102.80±9.68) μm, t=2.26, 3.06, 4.14, 4.84, 4.25, 4.88, all P<0.05]. In the nasal quadrant, the para-papillary RNFL of the no visual field defect group was significantly thinner compared with the control group [(61.45±9.83) μm vs. (69.67±14.23) μm, t=2.97, P<0.05]. The total GCL thickness was (30.48±5.42) μm in the visual field defect group, (31.35±2.77) μm in the no visual field defect group, thinner than that in the control group [(33.32±2.92) μm, t=2.92, 3.62; both P<0.05]. The total GCIPL thickness showed no significant difference among the three groups (P=0.07). In the superior and inferior temporal quadrants, the GCL and GCIPL thickness showed no significant difference among the three groups (all P>0.05). In the superior and inferior nasal quadrants, the GCL thickness was (29.41±5.97) μm, and (28.47±5.13) μm in the visual field defect group, (31.15±3.27) μm and (30.61±2.96) μm in the no visual field defect group, and (34.23±3.16) μm and (32.97±2.78) μm in the control group. The GCL thickness in the nasal quadrant was thinner in the visual field defect group (t=4.45, 4.82)and the no visual field defect group(t=4.23, 3.63) than in the control group (all P<0.01). However, no significant difference in GCL thickness was detected between the visual field defect group and the no visual field defect group (both P>0.05). In the superior and inferior nasal quadrants, the GCIPL thickness was (54.06±10.50) μm and (51.77±9.18) μm in the visual field defect group, (58.03±4.00) μm and (56.23±5.37) μm in the no visual field defect group, and (62.26±7.11) μm and (59.39±6.64) μm in the control group. The GCIPL thickness was thinner in the nasal quadrant in the visual field defect group than in the control group (t=3.95, 4.20, both P<0.01). Only in the Superior nasal quadrant, the GCIPL was significantly thinner in the no visual field defect group than the control group (t=3.25, P<0.01). Conclusion: The optic GCL may get thinner in pituitary nonfunctional adenoma with chiasm compression patients without the RNFL layer thinning and visual field defect. (Chin J Ophthalmol, 2019, 55: 186-194).

Potential retinal biomarkers for dementia: what is new?

To summarize the current findings on clinical retinal diseases and retinal imaging changes with dementia, focusing on Alzheimer's disease. Studies observed that clinical retinal diseases such as age-related macular degeneration, open-angle glaucoma and diabetic retinopathy are related to dementia, but the associations are not entirely consistent. In terms of the retinal neuronal structure, multiple retinal neuronal layers are significantly thinner in Alzheimer's disease dementia, such as the parapapillary retinal nerve fiber layer (RNFL) and macular ganglion cell-inner plexiform layer (GC-IPL). Recent studies further demonstrated that macular GC-IPL and macular RNFL are also significantly thinner in the preclinical stage of Alzheimer's disease. A thinner RNFL is also associated with a significantly increased risk of developing both cognitive decline and Alzheimer's disease dementia. In addition, studies consistently showed that retinal vascular changes are associated with poorer cognitive performance, as well as prevalent and incident Alzheimer's disease dementia. The current findings support the concept that changes in the retina, particular in retinal neuronal structure and vasculature, can reflect the status of cerebral neuronal structure and vasculature, highlighting the potential role of retinal changes as biomarkers of dementia.

Correlation of peripapillary retinal nerve fibre layer thickness with visual acuity in paediatric patients affected by optic pathway glioma.

To evaluate peripapillary retinal nerve fibre layer (RNFL) thickness, measured by spectral-domain optical coherence tomography (SD-OCT), as a surrogate of visual function in a population of paediatric patients affected by optic pathway glioma (OPG) associated with neurofibromatosis type 1 (NF1). A total of 38 paediatric patients (66 eyes) affected by MRI-proven OPG were included. Each patient underwent complete ophthalmological examination, including age-appropriate visual acuity (VA) assessment and RNFL analysis by SD-OCT. Visual acuity was classified as normal or pathologic using age-based normative data. Visual acuity was correlated to mean RNFL thickness of the whole peripapillary area and of each single analyzed sector (nasal, superior, temporal, inferior). Visual acuity was normal in 43 (65%) and pathologic in 23 (35%) eyes. Mean parapapillary RNFL thickness of each analyzed sector was significantly lower in eyes with abnormal VA (p<0.05). The best balanced cut-off value of global RNFL thickness allowing to discriminate between eyes with normal and pathologic VA was 76.25μm (91%, 76%, 67% and 94% of sensitivity, specificity, positive and negative predicting value, respectively). Considering best balanced cut-off values of other analyzed RNFL sectors, the superior (p=0.0029) and the inferior (p=0.0024) sectors reached the higher sensitivity (87% and 87%, respectively) and specificity (81% and 79%, respectively). Retinal nerve fibre layer thickness is directly related to VA in children affected by NF1-related OPG, and should be considered as a potential surrogate marker of VA. Retinal nerve fibre layer thickness cut-off values can be used in paediatric patients to discriminate false-positive results obtained by VA measurement.

Assessment of superficial retinal microvascular density in healthy myopia.

To evaluate retinal microvasculature in healthy myopia and investigate the correlation between microvascular density and ocular factors. A total of 174 eyes from 174 healthy Korean subjects were included. The eyes were divided into four groups according to refraction: emmetropia [21 eyes, - 1.00 D ≤ mean spherical equivalent (MSE) < + 0.75 D], mild myopia (32 eyes, - 3.00 D ≤ MSE < - 1.00 D), moderate myopia (76 eyes, - 6.00 D ≤ MSE < - 3.00 D), and high myopia (45 eyes, MSE < - 6.00 D). Images of retinal vasculature in parapapillary and parafoveal area were obtained using optical coherence tomography angiography. Superficial retinal microvascular density was measured for correlation analysis with ocular parameters. High myopia was found to have a lower superficial parapapillary microvascular density compared with the other groups in total parapapillary area, and in sectors of nasal and inferonasal (all p ≤ 0.001). The superficial parapapillary microvascular density showed a negative correlation with axial length (AL) and intraocular pressure (IOP) (β = - 0.479, p = 0.008 and β = - 0.160, p = 0.048, respectively), and a positive correlation with parapapillary retinal nerve fiber layer (RNFL) thickness (β = 0.140, p < 0.001). However, there was no significant difference in superficial parafoveal microvascular density among all groups (p > 0.05). This study reveals that superficial parapapillary microvascular density is lower in high myopia and has correlation with AL, IOP, and parapapillary RNFL thickness. It also indicates that superficial parafoveal microvascular density tends to be unaffected by healthy myopia. These retinal microvascular alterations may facilitate understanding the pathogenesis of glaucomatous optic nerve damage in high myopia.

Serial Combined Wide-Field Optical Coherence Tomography Maps for Detection of Early Glaucomatous Structural Progression

Both parapapillary and macular areas are important in determining the progression of early glaucoma. However, no attempt has been made to assess the progression of glaucoma in images that combine the 2 areas. To evaluate the potential usefulness of serial analysis of combined wide-field optical coherence tomography (OCT) maps for detection of structural progression in patients with early glaucoma. Retrospective observational study. Patients with early primary open-angle glaucoma with a minimum of 3-year follow-up involving serial spectral-domain OCT measurement were analyzed. Patients were divided into a nonprogressor group (n = 47) and a progressor group (n = 47) on the basis of serial stereo disc photography and red-free photography. Serial combined wide-field OCT maps integrating parapapillary retinal nerve fiber layer (RNFL) and macular ganglion cell-inner plexiform layer (GCIPL) maps were generated with the embedded software of serial spectral-domain OCT. Glaucoma specialists then assessed the structural progression detection ability of those serial wide-field OCT maps for early glaucomatous eyes and compared their sensitivity with those of RNFL and GCIPL guided progression analyses (GPAs). The diagnostic ability of the serial wide-field OCT maps for early glaucomatous structural progression. Ninety-four patients (mean [SD] age, 51.4 [12.3] years; 48 [51.1%] women; all Korean) were included. The serial wide-field OCT map analysis showed good agreement for detection of structural progression between the 2 glaucoma graders (wide-field OCT thickness map: κ = 0.649; wide-field OCT deviation map: κ = 0.833). These maps showed early glaucomatous structural progression detection abilities comparable with those of RNFL and GCIPL GPAs (sensitivities of wide-field OCT thickness map, wide-field OCT deviation map, RNFL GPA, and GCIPL GPA = 63.8%, 83.0%, 83.0%, and 66.0%, respectively, all P > .05; specificities of wide-field OCT thickness map, wide-field OCT deviation map, RNFL GPA, and GCIPL GPA = 93.6%, 95.7%, 84.8%, and 93.6%, respectively, all P > .05). The serial combined wide-field OCT maps integrating RNFL and GCIPL maps performed well in detecting structural progression in early glaucomatous eyes. Confirmation in an independent prospective study might provide greater confidence in this conclusion.

Integrating Macular Ganglion Cell Inner Plexiform Layer and Parapapillary Retinal Nerve Fiber Layer Measurements to Detect Glaucoma Progression

To investigate the temporal relationship among progressive macular ganglion cell inner plexiform layer (GCIPL) thinning, progressive parapapillary retinal nerve fiber layer (RNFL) thinning, and visual field (VF) progression in patients with primary open-angle glaucoma (POAG). Prospective study. One hundred thirty-six POAG patients (231 eyes) followed up for ≥5 years. OCT imaging of the macular GCIPL and parapapillary RNFL and perimetry were performed at ∼ 4-month intervals. Progressive GCIPL and RNFL thinning were determined by Guided Progression Analysis (GPA) of serial GCIPL and RNFL thickness maps. The specificities of GPA were calculated from the proportions of eyes with progressive GCIPL or RNFL thinning in 67 eyes of 36 healthy individuals followed up for ≥5 years. Visual field progression (likely or possible) was determined by the Early Manifest Glaucoma Trial criteria. Hazard ratios for VF progression, progressive RNFL thinning, and progressive GCIPL thinning, as determined by time-varying Cox models. GPA detected 57 eyes (24.7%) with progressive GCIPL thinning and 66 eyes (28.6%) with progressive RNFL thinning at a specificity of 95.5% and 91.0%, respectively. Thirty-five eyes (15.2%) demonstrated progressive RNFL and GCIPL thinning, whereas 53 eyes (22.9%) demonstrated progressive RNFL or GCIPL thinning. Eyes with progressive GCIPL thinning had a higher risk for progressive RNFL thinning (HR, 5.27; 95% confidence interval [CI], 2.89-9.62), whereas eyes with progressive RNFL thinning were also at a higher risk for progressive GCIPL thinning (HR, 2.99; 95% CI, 1.48-6.02), after adjusting for baseline covariates. The HRs for likely and possible VF progression were 3.48 (95% CI, 1.51-8.01) and 2.74 (95% CI, 1.26-5.98), respectively, on detection of progressive GCIPL thinning and 3.66 (95% CI, 1.68-7.97) and 2.54 (95% CI, 1.23-5.21), respectively, on detection of progressive RNFL thinning after adjusting for baseline covariates. Eyes with VF progression were not at risk of progressive RNFL or GCIPL thinning (P ≥ 0.493). Progressive macular GCIPL thinning and progressive parapapillary RNFL thinning are mutually predictive. Because progressive RNFL thinning and progressive GCIPL thinning are both indicative of VF progression, integrating macular GCIPL and parapapillary RNFL measurements is relevant to facilitate early detection of disease deterioration in glaucoma patients.

Evaluation of macular ganglion cell complex and peripheral retinal nerve fiber layer structural damage in early primary glaucomous eyes by 3D-OCT

Background In previous study, peripheral retinal nerve fiber layer (RNFL) thickness is considered to be the earliest structural changes which can be detected.3D-OCT can measure the thickness of macular ganglion cell complex (mGCC), which makes the detection of primary glaucoma possible in the early stage. Objective This study was to measure the thickness of mGCC and disc-peripheral RNFL in early stage of primary glaucomous eyes by 3D-OCT and assess the anatomic basis of glaucoma-induced optical nerve damage. Methods 3D-OCT images from 10 patients with advanced stage primary glaucoma in one lateral eye and early stage glaucoma in fellow eye from December 2010 to December 2012 were prospectively analyzed in China-Japan Friendship Hospital.The patients were diagnosed based on the recommended standard of National glaucoma group (1987 version) and received routine eye examination.3D-OCT scanning was performed using 3D-macular mode, 3D-macular Wide mode and 3D-disc mode with TOPCON 3D-OCT 2000 system, and the images at macular 6 mm×6 mm area were analyzed.The posterior pole area was divided into 5 concentric rings from fovea toward periphery and equally subdivided into 100 small checks, with the area of 0.6 mm×0.6 mm for each.The probable values in each check were calculated as the ratio of each figure and corresponding normal value.The probable values were expressed as red color (P<1%), yellow color (P<5%) and gray color (P≥5%). Then the disc-periphery RNFL thickness and disc cup were evaluated. Results No evident abnormality was found in the thicknesses of photoreceptors layer and bipolar cell layer in both advanced glaucomous eyes and the early stage of glaucomous eyes in the 10 patients.Serious damage of visual field was seen in the advanced glaucomous eyes and presented with red color in the parapapillary RNFL area, mGCC area and macular RNFL area, showing an evidently attenuation of the thicknesses of parapapillary RNFL, mGCC and RNFL.However, the visual field was close normal in the early stage glaucomous eyes, and mGCC and macular RNFL showed yellow color, while green or yellow color was exhibited in the parapapillary RNFL area, indicating mGCC and macular RNFL thickness was reduced, but parapapillar RNFL thickness was near normal. Conclusions The change of mGCC thickness is earlier than that of peripheral RNFL at optic disc in primary glaucomaous eyes, which may imply that the disappear of macular ganglion cell body is earlier than that of the axon. Key words: Glaucoma, primary; Optical coherence tomography; Biometry; Retinal nerve fiber; Retinal ganglion cells; Retinal ganglion cell complex

Structure–function relationship among three types of spectral‐domain optical coherent tomography instruments in measuring parapapillary retinal nerve fibre layer thickness

To compare the relationships of parapapillary retinal nerve fibre layer (RNFL) thickness among three spectral-domain optical coherence tomography (SD-OCT) instruments with visual field sensitivity (VFS). One hundred and thirteen eyes of 113 Japanese subjects with glaucoma (mean deviation in standard automated perimetry = -8.9 ± 6.7 dB) were imaged by Cirrus, RTVue and 3D OCT. The average hemi-superior and hemi-inferior RNFL thicknesses were obtained. In addition, the structure-function relationship using two retinotopic maps that consisted of six or nine sectors was also evaluated. Decibel (dB) scale and 1/Lamert (1/L) were used to express VFS. RNFL thickness correlation with corresponding VFS in visual field sectors was compared among the three instruments. Background RNFL thickness (non-neuronal tissue) for each instrument was estimated using a linear regression model at 1/L = 0. The correlation between the average hemi-superior and hemi-inferior RNFL thickness in the three SD-OCT instruments with corresponding VFS was similar. In the analysis of retinotopic maps, 3D OCT showed a higher correlation in superotemporal sectors than RTVue, whereas RTVue had a stronger relationship in the nasal sector than Cirrus. The background RNFL thickness extrapolated was approximately 60% that of normal eyes in all the instruments. The three SD-OCT showed similar overall correspondence with VFS with a partially discordant retinotopic relationship. RNFL measured with any SD-OCT devices likely contains non-neuronal tissue, comprising 60% of its thickness.

Effects of ocular rotation on parapapillary retinal nerve fiber layer thickness analysis measured with spectral-domain optical coherence tomography

To evaluate the effects of ocular rotation on parapapillary retinal nerve fiber layer (RNFL) thickness measured by spectral-domain optical coherence tomography (SD-OCT). Eighty-eight normal and 205 glaucomatous eyes were studied. RNFL thickness was measured by 3D OCT. Ocular rotation angle was measured from a fundus image obtained by a non-mydriatic fundus camera equipped with 3D OCT. The average, hemi-superior, and hemi-inferior RNFL thicknesses as well as those in the 4 quadrants and the 16-segmented superotemporal (ST-1) and inferotemporal (IT-4) sectors were compared both before and after correcting for ocular rotation. Receiver operating characteristic curves and the areas under the curve (AUC) for the RNFL thicknesses were calculated on the basis of the data from glaucomatous and control eyes. The relationships between RNFL thickness and retinal sensitivity in the corresponding visual field were analyzed using a Humphrey field analyzer. Correction for ocular rotation did not affect the AUCs of the hemi-superior and hemi-inferior RNFL thicknesses. RNFL thicknesses in all of the quadrants and in ST-1 and IT-4 were significantly changed by correcting for ocular rotation. The correlations between all RNFL sectors and retinal sensitivity were not changed by correcting for the ocular rotation angle. Ocular rotation compensation affected RNFL thickness measurement with 3D OCT. However, the effect was clinically negligible in the diagnosis of glaucoma.

Agreement among three types of spectral-domain optical coherent tomography instruments in measuring parapapillary retinal nerve fibre layer thickness

Backgrounds/aimsTo evaluate the agreement of parapapillary retinal nerve fibre layer (RNFL) thickness among three spectral-domain optical coherence tomography (OCT) instruments.MethodsTwo hundred and three glaucomatous eyes and 88 normal eyes were...

Structure-function Relationships Using the Cirrus Spectral Domain Optical Coherence Tomograph and Standard Automated Perimetry

To evaluate the relationship between glaucomatous structural damage assessed by the Cirrus Spectral Domain OCT (SDOCT) and functional loss as measured by standard automated perimetry (SAP). Four hundred twenty-two eyes (78 healthy, 210 suspects, 134 glaucomatous) of 250 patients were recruited from the longitudinal Diagnostic Innovations in Glaucoma Study and from the African Descent and Glaucoma Evaluation Study. All eyes underwent testing with the Cirrus SDOCT and SAP within a 6-month period. The relationship between parapapillary retinal nerve fiber layer thickness (RNFL) sectors and corresponding topographic SAP locations was evaluated using locally weighted scatterplot smoothing and regression analysis. SAP sensitivity values were evaluated using both linear as well as logarithmic scales. We also tested the fit of a model (Hood) for structure-function relationship in glaucoma. Structure was significantly related to function for all but the nasal thickness sector. The relationship was strongest for superotemporal RNFL thickness and inferonasal sensitivity (R(2)=0.314, P<0.001). The Hood model fitted the data relatively well with 88% of the eyes inside the 95% confidence interval predicted by the model. RNFL thinning measured by the Cirrus SDOCT was associated with correspondent visual field loss in glaucoma.

Evaluation of the Optic Nerve and Retinal Nerve Fiber Layer in Myopic Individuals

Clinical discrimination between myopic tilted optic discs and glaucomatous optic neuropathy is often challenging, especially when considering that myopia is a risk factor for the development of glaucoma. Myopic tilted discs are usually larger than average, with associated relative cupping and thinner neuroretinal rim tissue. Histopathologic study has revealed thinner parapapillary retinal tissue in these eyes. Optical coherence tomography (OCT)-measured average retinal nerve fiber layer (RNFL) thickness has been found to decrease with longer axial length and higher myopic refractive error. Parapapillary RNFL quadrant and clock-hour analyses result in a higher false-positive rate in myopic eyes. Careful slit-lamp examination, quality baseline stereoscopic disc photographs, and frequent serial visual field testing are essential to the follow-up of myopic individuals with suspected glaucoma. A novel diagnostic parameter, OCT-derived ganglion cell analysis, may prove to be useful in the diagnosis and follow-up of these individuals.

Evaluation of the Optic Nerve and Retinal Nerve Fibre Layer in Myopic Individuals

Clinical discrimination between myopic tilted optic discs and glaucomatous optic neuropathy is often challenging, especially when considering that myopia is a risk factor for the development of glaucoma. Myopic tilted discs are usually larger than average, with associated relative cupping and thinner neuroretinal rim tissue. Histopathological study has revealed thinner parapapillary retinal tissue in these eyes. Optical coherence tomography (OCT)-measured average retinal nerve fibre layer (RNFL) thickness has been found to decrease with longer axial length and higher myopic refractive error. Parapapillary RNFL quadrant and clock-hour analyses result in a higher false-positive rate in myopic eyes. Careful slit-lamp examination, quality baseline stereoscopic disc photographs and frequent serial visual field testing are essential to the follow-up of myopic individuals with suspected glaucoma. A novel diagnostic parameter, OCT-derived ganglion cell analysis, may prove to be useful in the diagnosis and follow-up of these individuals.