Peripapillary Retinal Nerve Fiber Layer Thickness Research Articles

Evaluation of optic nerve head vessels density changes after phacoemulsification cataract surgery using optical coherence tomography angiography.

To evaluate optic nerve head (ONH) vessel density (VD) changes after cataract surgery using optical coherence tomography angiography (OCTA). This was a prospective observational study. Thirty-four eyes with mild/moderate cataracts were included. ONH scans were obtained before and 3mo after cataract surgery using OCTA. Radial peripapillary capillary (RPC) density, all VD, large VD and retinal nerve fiber layer thickness (RNFLT) in total disc, inside disc, and different peripapillary sectors were assessed and analyzed. Image quality score (QS), fundus photography grading and best-corrected visual acuity (BCVA) were also collected, and correlation analyses were performed between VD change and these parameters. Compared with baseline, both RPC and all VD increased in inside disc area 3mo postoperatively (from 47.5%±5.3% to 50.2%±3.7%, and from 57.87%±4.30% to 60.47%±3.10%, all P<0.001), but no differences were observed in peripapillary area. However, large VD increased from 5.63%±0.77% to 6.47%±0.72% in peripapillary ONH region (P<0.001). RPC decreased in inferior and superior peripapillary ONH parts (P=0.019, <0.001 respectively). There were obvious negative correlations between RPC change and large VD change in inside disc, superior-hemi, and inferior-hemi (r=-0.419, -0.370, and -0.439, P=0.017, 0.044, and 0.015, respectively). No correlations were found between VD change and other parameters including QS change, fundus photography grading, postoperative BCVA, and postoperative peripapillary RNFLT. RPC density and all VD in the inside disc ONH region increase 3mo after surgery in patients with mild to moderate cataract. No obvious VD changes are found in peripapillary area postoperatively.

Peripapillary vessel density in healthy people, primary open-angle glaucoma, and normal-tension glaucoma.

To compare peripapillary vessel density using optical coherence tomography angiography (OCT-A) in eyes of healthy people, primary open-angle glaucoma (POAG), and normal-tension glaucoma (NTG). Thirty patients with POAG, 27 patients with NTG, and 29 healthy individuals in the control group were assessed. Capillary vessels in peripapillary retinal nerve fiber layer (RNFL) represented by whole image RPC (radial peripapillary capillary) density in an AngioDisc scan 4.5 × 4.5 mm centered on the optic disc, and ONH morphological variables (disc area, rim area, cup to disc area ratio (CDR)), and average peripapillary RNFL thickness were measured. Differences in mean RPC, RNFL, disc area, rim area, and CDR between the groups were statistically significant (P < 0.05). The difference in RNFL thickness and rim area was not significant between NTG and healthy groups, while RPC and CDR showed a statistically significant difference between all pairs. The vessel density in the POAG group was 8.25% and 11.7% lower compared to the NTG and healthy groups, respectively; while the mean difference was less (2.97%) for the NTG and healthy group. In the POAG group, 67.2% of the variation in RPC can be explained by a model containing CDR and RNFL thickness, and in normal eyes 38.8% of the changes using a model containing RNFL. The peripapillary vessel density is reduced in both types of glaucoma. The vessel density in NTG was significantly lower than in the healthy eyes, despite the lack of significant difference in RNFL thickness and neuroretinal rim area between them.

Association of long-term exposure to ambient air pollution with retinal neurodegeneration: the prospective Alienor study

Chronic exposure to air pollution may have adverse effects on neurodegenerative diseases. Glaucoma, the second leading cause of blindness worldwide, is a neurodegenerative disease of the optic nerve, characterized by progressive thinning of the retinal nerve fiber layer (RNFL). We investigated the relationship of air pollution exposure with longitudinal changes of RNFL thickness in the Alienor study, a population-based cohort of residents of Bordeaux, France, aged 75 years or more. Peripapillary RNFL thickness was measured using optical coherence tomography imaging every 2 years from 2009 to 2020. Measurements were acquired and reviewed by specially trained technicians to control quality. Air pollution exposure (particulate matter ≤2.5 μm (PM2.5), black carbon (BC), nitrogen dioxide (NO2)) was estimated at the participants’ geocoded residential address using land-use regression models. For each pollutant, the 10-year average of past exposure at first RNFL thickness measurement was estimated. Associations of air pollution exposure with RNFL thickness longitudinal changes were assessed using linear mixed models adjusted for potential confounders, allowing for intra-eye and intra-individual correlation (repeated measurements).The study included 683 participants with at least one RNFL thickness measurement (62% female, mean age 82 years). The average RNFL was 90 μm (SD:14.4) at baseline. Exposure to higher levels of PM2.5 and BC in the previous 10 years was significantly associated with a faster RNFL thinning during the 11-year follow-up (−0.28 μm/year (95% confidence interval (CI) [-0.44;-0.13]) and −0.26 μm/year (95% CI [-0.40;-0.12]) per interquartile range increment; p < 0.001 for both). The size of the effect was similar to one year of age in the fitted model (−0.36 μm/year). No statistically significant associations were found with NO2 in the main models.This study evidenced a strong association of chronic exposure to fine particulate matter with retinal neurodegeneration, at air pollution levels below the current recommended thresholds in Europe.

Factors Affecting Visual Acuity and Central Visual Function in Glaucoma Patients With Myopia

To investigate associated factors including structural parameters of myopia and vessel density (VD) using optical coherence tomography angiography (OCT-A) to visual acuity (VA) and central visual function in glaucoma patients with myopia. Retrospective cross-sectional study METHODS: Sixty-five eyes of 60 glaucoma patients with myopia and without media opacity and retinal lesions were include. Both Swedish interactive thresholding algorithm (SITA) 24-2 and 10-2 visual field (VF) testing were performed. Superficial and deep VD in the peripapillary and macular regions were evaluated using OCT-A; retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) thicknesses were measured. β-zone peripapillary atrophy (PPA) area, disc torsion, disc-fovea distance, and peripapillary choroidal thickness were measured. Decreased VA was defined as best-corrected VA <20/25. The worse mean deviation of SITA 24-2, thinner GCIPL thickness, and lower deep peripapillary VD were associated with the presence of central VF damage in glaucoma patients with myopia. Thinner GCIPL thickness, lower deep peripapillary VD, and longer disc-fovea distance were associated with decreased VA in logistic regression analysis. Thinner GCIPL thickness, lower deep peripapillary VD, and larger β-zone PPA area were associated with lower VA in linear regression analysis. Deep peripapillary VD showed a positive correlation with GCIPL thickness, whereas there was no relationship between deep peripapillary VD and RNFL thickness. Decreased VA in glaucoma patients with myopia was associated with lower deep peripapillary VD and papillomacular bundle damage. Lower deep peripapillary VD was independently associated with decreased VA along with thinner GCIPL thickness. Therefore, this could be stated that decreased VA in glaucoma patients is related to the damage location and the status of blood flow in the optic nerve head.

Short-term effect of macular edema on the peripapillary retinal nerve fiber layer in patients with wet age-related macular degeneration and diabetic macular edema: A comparative study

BackgroundThe combined presence of glaucoma and age-related macular degeneration (ARMD), or glaucoma and diabetes mellitus (DM), occur fairly frequently, especially in elderly patients. This study was intended to compare the effect of resolving macular edema due to DM and wet ARMD on peripapillary retinal nerve fiber layer (RNFL) thickness. MethodsThis cross-sectional study included 76 patients with macular edema secondary to DM (n = 40, 52.6%) or wet ARMD (n = 36, 47.4%). The control group was comprised of 34 age and sex-matched healthy subjects. All study participants underwent evaluation of central macular thickness (CMT) and the peripapillary RNFL using spectral domain-optical coherence tomography (SD-OCT). Data from eyes that received an anti-VEGF injection were obtained one month after the procedure and were compared with pre-injection data. ResultsThe average initial thickness of the global peripapillary RNFL was 98.9 ± 16.7 (61–163) µm in the macular edema group and 92.0 ± 16.0 (84–115) µm in the control group (p = 0.045). The post-injection global peripapillary RNFL thickness was 97.3 ± 19.0 (61–163) µm in the macular edema group and 92.2 ± 18.0 (81–126) µm in the control group (p = 0.187). In the DM group, the changes in global RNFL thickness, as well as central and temporal quadrant thicknesses, were found to correlate significantly with the change in CMT (r = 0.356, p = 0.024; r = 0.545, p < 0.001, respectively). ConclusionsMacular edema in wet ARMD appeared not to affect RNFL thickness. Differences in the etiology of macular edema can have varied effects on peripapillary RNFL. It is recommended that peripapillary RNFL thickness be evaluated cautiously in DM patients receiving intravitreal anti-VEGF therapy.

Refractive status and retinal morphology in children with a history of intravitreal ranibizumab for retinopathy of prematurity.

This study investigated the characteristics of refractive status, visual acuity, and retinal morphology in children with a history of receiving intravitreal ranibizumab for retinopathy of prematurity (ROP). Children 4-6years of age were enrolled and divided into the following four groups: group 1, children with a history of ROP who had been treated with intravitreal ranibizumab; group 2, children with a history of ROP who had not received any treatment; group 3, premature children without ROP; and group 4, full-term children. Refractive status, peripapillary retinal nerve fiber layer (RNFL), and macular thickness were measured. A total of 204 children were enrolled. In group 1, myopic shift was not noted, but poorer best corrected visual acuity (BCVA) and shorter axial length were observed. Significantly lower peripapillary RNFL thickness in the average total and superior quadrant, higher central subfield thickness, lower parafoveal retinal thickness in average total, superior, and nasal and temporal quadrants were observed in group 1 than in the other groups. The poor BCVA in patients with ROP was correlated with the lower RNFL thickness in the superior quadrant. Conclusion: Children with a history of type 1 ROP treated with ranibizumab did not show a myopic shift but did show abnormal retinal morphology and the poorest BCVA among all groups. We suggest that pediatric ophthalmologists should always pay attention to visual development in patients with ROP with a history of intravitreal ranibizumab. What is Known: • Anti-VEGF is efficiently and widely used in the treatment of type 1 retinopathy of prematurity (ROP), and different anti-VEGF agents are associated with different prevalence of myopia. • Patients with ROP who receive treatment such as laser therapy or cryotherapy have abnormal macular development and retinal nerve fiber layer (RNFL) thickness. What is New: • Children with a history of ROP treated with intravitreal ranibizumab did not show a myopic shift but did show poor BCVA at 4-6years of age. • Abnormal macular morphology and lower peripapillary RNFL thickness were found in these children.

Factors Associated with Visual Acuity in Advanced Glaucoma.

This study aimed to comprehensively analyze various parameters in advanced glaucoma patients to identify the factors that can affect best-corrected visual acuity (BCVA) in advanced glaucoma. This cross-sectional retrospective study included 113 patients (mean age, 61.66 ± 13.26 years; males, 67) who had advanced glaucomatous damage (113 eyes; mean BCVA, 0.18 ± 0.38 logMAR; mean deviation of 30-2 visual field [VF], -19.08 ± 6.23 dB). Peripapillary retinal nerve fiber layer (RNFL) and total and segmented macular thickness (RNFL, ganglion cell layer (GCL), and inner plexiform layer (GCL)) were measured using Spectralis optical coherence tomography (OCT). Correlations between BCVA and OCT parameters or 30-2 VF parameters were assessed using Pearson correlation analysis. Multivariate regression analysis was performed to determine the factors associated with BCVA in advanced glaucoma patients. Peripapillary RNFL thickness, subfoveal choroidal thickness, and global macular RNFL, GCL, IPL, and total thickness were found to be significantly correlated with BCVA and central visual function. Multivariate analysis showed a significant correlation between subfoveal choroidal thickness and BCVA. In addition, central VF mean sensitivity, especially inferior hemifield, showed a significant relationship with BCVA. In conclusion, subfoveal choroidal thickness and central VF sensitivity, especially the inferior hemifield area, are factors that affect BCVA in advanced glaucoma.

Association of Optic Nerve Head and Macular Optical Coherence Tomography Measures With Glaucoma-Related Disability.

Optical coherence tomography (OCT) estimated retinal nerve fiber layer (RNFL) thickness associated with glaucoma-related disability independent of the visual field (VF) damage and thus may provide additional patient-relevant disability information beyond what is captured by standard VF testing. To examine whether OCT metrics [peripapillary RNFL thickness and macular ganglion cell/inner plexiform layer (GCIPL) thickness] are associated with quality of life (QoL) measures and additional disability metrics, and whether these associations are independent of VF damage. In this cross-sectional study, 156 patients with glaucoma or suspected glaucoma received VF testing and OCT scans to measure RNFL and GCIPL thickness. QoL was assessed using the Glaucoma Quality-of-Life 15 and additional disability measures including fear of falling, reading speed, and steps per day were assessed. Multivariable regression models adjusting for relevant covariates tested whether RNFL or GCIPL thickness from the less-impaired eye were associated with disability measures and whether associations were independent of VF damage. Greater VF damage is associated with worse QoL (95% CI=0.4-1.4; P <0.001) and slower reading speed (CI=-0.06 to -0.02; P <0.001). Lower RNFL and GCIPL thicknesses were associated with lower QoL scores, but not with QoL scores or other disability metrics after correcting for VF damage. However, post hoc analyses in patients with better eye thicknesses between 55 and 75µm demonstrated associations between lower RNFL thickness and worse QoL (CI=-2.2 to -0.1; P =0.04) and greater fear of falling (CI=-6.1 to -0.4; P =0.03) even after accounting for VF damage. No such associations were observed for GCIPL thickness. OCT RNFL, but not GCIPL, thickness is associated with multiple disability measures independent of VF damage severity.

Retinal Nerve Fiber Layer Imaging with Two Different Spectral Domain Optical Coherence Tomographs: Normative Data for Romanian Children.

The purpose of this study is to analyze and compare pediatric normative data for the retinal nerve fiber layer of Romanian children using two different spectral domain optical coherence tomographs. Due to different scanning speeds and axial and transverse resolution, the results of the measurements of scans cannot be transposed. A total of 140 healthy children aged 4 to 18 were enrolled in the study. Overall, 140 eyes were scanned with a Spectralis SD-OCT (Heidelberg Technology), and the other 140 eyes were imaged with a Copernicus REVO SOCT (Optopol Technology (Zawiercie, Poland)). The mean global RNFL thickness and average RNFL thickness for the four quadrants were measured and compared. The average peripapillary RNFL thickness measured with the Spectralis was 104.03 ± 11.42 (range 81 to 126 µm), while the one measured with the Revo 80 was 127.05 ± 15.6 (range 111.43-158.28). The RNFL thickness measurements taken with the Spectralis in the superior, inferior, nasal, and temporal quadrants were 132 ±19.1, 133.5 ± 21.77, 74 ± 16.48, and 73 ± 11.95 µm, respectively, while those taken with the Revo 80 were 144.44 ± 9.25, 144.86 ±23.12, 96.49 ± 19.41, and 77 ± 11.4 µm, respectively. Multivariate analysis showed that the average RNFL thickness was not influenced by gender or eye laterality and was negatively correlated with age when we used the Spectralis device. This study provides normative data for SD-OCT peripapillary RNFL in healthy Romanian children for two different tomographs. These data help the clinician evaluate and interpret the results of optical coherence tomography for a child, taking into consideration all the technical and individual parameters.

The Effects of Long-term Growth Hormone Treatment on Ocular Findings.

This study aimed to examine the long-term changes in anterior chamber depth (ACD), central corneal thickness (CCT), axial length (AxL), peripapillary retinal nerve fibre layer thickness (RNFLT), peripapillary ganglion cell layer - inner plexiform layer (GCL-IPL) thickness, and peripapillary choroidal thickness (ChT) after rhGH replacement treatment in paediatric patients with IGHD, compared to healthy controls. Twenty-two children with IGHD including 12 girls and 10 boys were enrolled in the study group, and 30 (16 girls, 14 boys) healthy children composed the control group. A detailed ophthalmological examination was performed for each participant. ACD, CCT, AxL, peripapillary RNFLT, GCL-IPL thickness and ChT measurements were performed before the rhGH replacement treatment and in the 12th month of the post-treatment period, as well as the corresponding visits in the control group. AxL ultrasound pachymetry (CCT), peripapillary RNFL thickness, peripapillary RNFLT, GCL-IPL thickness, and peripapillary ChT parameters were measured by spectral-domain optical coherence tomography. The mean age of the groups were similar (p = 0.143). 12-month CCT, ACD, and AxL measurements of the study group showed significantly higher results than the pre-treatment measurements (p = 0.005, p = 0.024, and p = 0.002, respectively). Similarly, the mean RNFLT and ChT measurements of the study group obtained from all sectors were significantly higher in the 12th-month visit (p < 0.001 for both) other than the RNFLT, and GCL-IPL thickness measurements (p > 0.05 for all). However, all these parameters were similar at pre- and post-treatment visits in the control group (p > 0.05 for all). The mean pre-treatment values of all these parameters were significantly lower in the study group compared to the control group (p < 0.05 for all), other than the RNFLT, GCL-IPL thickness measurements (p > 0.05 for all), while the mean post-treatment values of all these parameters in both groups were similar at month 12 (p > 0.05 for all). GH replacement treatment in childhood may play an important role in the development of the neural retina and can be effective on the anterior segment, RNFLT and ChT measurements.

Optical coherence tomography analysis of the optic nerve head and macula of the fellow eye in acute unilateral nonarteritic anterior ischemic optic neuropathy

The objective of the study was to compare the thickness of the retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) of the fellow eyes of patients with acute nonarteritic anterior ischemic optic neuropathy (NAAION) to those of control subjects. This study included 46 patients with NAAION matched for age, sex and refraction data (spherical equivalent and/or axial length) to 46 control subjects. The anatomical parameters assessed using the Cirrus SD-OCT were the mean RNFL thickness, in the 4 quadrants (inferior, nasal, temporal, superior) and according to the 12 hourly meridians, GCC mean and in 6 quadrants centered on the fovea (infero-nasal, supero-nasal, infero-temporal, supero-temporal, superior and inferior) and parameters of the optic disc (Cup ratio - Vertical and Average Disc, Rim Area, Disc Area, Cup Volume). Compared to the control group, the eyes contralateral to those affected by NAAION showed a greater value of the area of the neuro-retinal rim (rim area), and a smaller vertical cup/disc (C/D) ratio, mean C/D, and cup volume than the control group. There was no significant difference between the two groups for peripapillary RNFL thickness and GCC parameters. The absence of damage to the RNFL or GCC of the unaffected fellow eyes of patients with NAAION does not explain the perimetric damage. The eyes contralateral to those affected by NAAION are characterized by an overall size of the optic disc identical to those of the control subjects, but a smaller cup, a recognized risk factor for NAAION.

Longitudinal Changes in Peripapillary and Macular Vessel Densities in Glaucomatous Eyes With a Single-Hemifield Retinal Nerve Fiber Layer Defect.

The peripapillary vessel density decreased significantly in the affected hemiretina compared with that in the intact hemiretina in glaucomatous eyes with a single-hemifield retinal nerve fiber layer defect. To evaluate the difference in the change rates of peripapillary vessel density (pVD) and macular vessel density (mVD) measured using optical coherence tomography angiography (OCTA) in glaucomatous eyes with a single-hemifield retinal nerve fiber layer (RNFL) defect. We performed a retrospective, longitudinal study of 25 patients with glaucoma who were followed up for at least 3 years, with a minimum of 4 visits after baseline OCTA. At each visit, all participants underwent OCTA examination, and the pVD, mVD were measured by removing the large vessels. Changes in the pVD, mVD, peripapillary RNFL thickness (pRNFLT), and macular ganglion cell inner plexiform layer thickness were investigated in the affected and intact hemispheres, and the differences between the 2 hemispheres were compared. In the affected hemiretina, the pVD, mVD, pRNFLT, and mCGIPLT were reduced than that in the intact hemiretina (all, P < 0.001). The changes in pVD and mVD were statistically significant at the 2-year and 3-year follow-ups in the affected hemifield (all, P <0.05). However, pVD and mVD did not show statistically significant changes in the intact hemiretina throughout the follow-up visits. Although the pRNFLT decreased significantly at the 3-year follow-up, the macular ganglion cell inner plexiform layer thickness showed no statistical change at any follow-up visit. Compared with the intact hemisphere, pVD was the only parameter that showed significant changes throughout the follow-up period. Although pVD and mVD decreased in the affected hemiretina, the reduction in pVD was significant compared with that in the intact hemiretina.

Study of retinal nerve fiber layer thickness in diabetic patients using optical coherence tomography.

This study aimed to assess and compare the changes in peripapillary retinal nerve fiber layer (RNFL) thickness in nondiabetics and diabetics with various stages of diabetic retinopathy (DR). The study subjects were divided into four groups based on their diabetic status and findings, namely, controls (normal subjects without diabetes [NDM]), diabetics without retinopathy (NDR), nonproliferative DR (NPDR), and proliferative DR (PDR). Peripapillary RNFL thickness was assessed using optical coherence tomography. One-way analysis of variance (ANOVA) with the post-Tukey HSD test was done to compare RNFL thickness in different groups. The Pearson coefficient was used to determine the correlation. There was statistically significant difference in measured average RNFL (F = 14.8000, P < 0.05), superior RNFL (F = 11.7768, P < 0.05), inferior RNFL (F = 12.9639, P < 0.05), nasal RNFL (F = 12.2134, P < 0.05), and temporal RNFL (F = 4.2668, P < 0.05) across the different study groups. Pairwise comparison showed that there was a statistically significant difference in RNFL measured (average and all quadrants) in patients with DR (NPDR and PDR) and the NDM control group (P < 0.05). In diabetics without retinopathy, the RNFL measured was reduced compared to controls, but it was statistically significant only in the superior quadrant (P < 0.05). Average RNFL and RNFL in all quadrants showed a small negative correlation with the severity of DR and it was statistically significant (P < 0.001). In our study, peripapillary RNFL thickness was reduced in diabetic retinopathy compared to normal controls and the thinning increased with the severity of DR. This was evident in the superior quadrant even before the fundus signs of DR set in.

Changes in Ocular Biomarkers from Normal Cognitive Aging to Alzheimer's Disease: A Pilot Study.

To identify ophthalmic findings in Alzheimer's type dementia (ATD) compared to normal subjects. This comparative descriptive study included participants from the institution's cognitive fitness center. Complete ophthalmic examinations were performed. Optical coherence tomography (OCT) and OCT angiography (OCTA) were used to analyze retinal thickness and vascular density. The Ocular Surface Disease Index (OSDI) score and tear breakup time (TBUT) were used to assess dry eye. The blink rate was counted by a well-trained observer. Cognitive function was evaluated using the Thai Mental State Examination (TMSE) score. Correlation analysis was performed to compare OCT, OCTA parameters, and TMSE. We included 24 ATD patients and 39 normal participants as a control group by age and sex-matched. The prevalence of dry eye using the Asia Dry Eye Society criteria was 15% and 13% in normal and ATD patients, respectively. The differences in OSDI scores, TBUT, and blink rate between the two groups were not statistically significant. The parafoveal and perifoveal macular thickness of the ATD group were significantly lower than that of the control group (p<0.01). All parameters of the vessel density of the ATD group were significantly lower than in the control group, including the whole macular vessel density (p<0.01), optic disc vessel density at the nerve head level (p<0.01), and optic disc vessel density at the radial peripapillary capillary level (p<0.05). After age adjustment, there were no statistically significant differences in all the OCT and OCTA parameters. There was a positive correlation between retinal thickness and vessel density in the macular and optic disc region and TMSE scores. Perifoveal and parafoveal retinal thickness might be more sensitive than peripapillary RNFL thickness to detect neurodegenerative changes in patients with ATD. Macular thickness and vessel density reduction were also positively correlated with cognitive decline.

Optic disc tilt and rotation effects on positions of superotemporal and inferotemporal retinal nerve fibre layer peaks in myopic Caucasians

ABSTRACT Clinical relevance In myopic eyes, the optic disc may become tilted and rotated, making glaucoma diagnosis more difficult. Background To determine the presence of tilted optic disc, the degree of optic disc rotation, and their effects on the angular location of superotemporal and inferotemporal retinal nerve fibre layer (RNFL) peaks in healthy myopic Caucasians. Methods Non-glaucomatous healthy myopic Caucasian eyes with an axial length > 24 mm were evaluated. ImageJ was used to quantify optic disc tilt and torsion on red-free fundus photography. The RNFL was scanned using spectral-domain optical coherence tomography. The angle of the superotemporal and inferotemporal peaks with the vertical-horizontal meridian was measured. Results Fifty-four eyes of 54 individuals were evaluated. The axial length was correlated with the angular location for both the superotemporal (r = −0.549, p < 0.001) and inferotemporal (r = −0.415, p = 0.002) RNFL peaks; they were placed more temporally in eyes with higher axial lengths. For each 1 mm increase in axial length, the angle between the superotemporal peak and the temporal horizontal meridian decreased by 3.976°, and the angle between the inferotemporal apex and the temporal horizontal meridian decreased by 3.028°. The angle between the inferotemporal peak and the temporal horizontal meridian decreased by 0.231° for each 1° increase in optical disc torsion (R2 = 0.09 Regression coefficient = −0.231, p = 0.027). Conclusions The temporal shift of superior and inferior peaks, the thickening of temporal and nasal RNFL, the presence of tilted optic disc, and optic disc rotation may cause misinterpretation of the RNFL in myopic Caucasians. When evaluating peripapillary RNFL thickness in myopic individuals, it would be better to consider these to avoid misinterpretation.

Optical Coherence Tomography Angiography for the Differentiation of Glaucoma from Pituitary Macroadenoma Related Optic Disc Measurements

ABSTRACT Objective To determine the potential of optical coherence tomography (OCT) and OCT angiography (OCTA) to distinguish between glaucoma and pituitary macroadenoma by optic disc appearance. Methods This prospective case-control study comprised 31 patients: 23 with glaucoma (18 male, 5 female) and 8 with pituitary macroadenoma and chiasmatic compression (3 male, 5 female). The corresponding mean ages were 72.8 years (range 58–90) and 60.7 years (range 43–73). All participants underwent complete ophthalmological examination, spectral domain OCT and OCTA, and visual field testing. Clinical, imaging, and visual field results were compared between the groups. Results On OCT analysis, the glaucoma group had relatively lower peripapillary retinal nerve fiber layer (RNFL) thickness (65.79 ± 15.46, 86.0 ± 11.37, respectively, P = .002) and lower rim area (1.00 ± 0.22 mm2 and 1.2 ± 0.15 mm2, respectively, P = .005). On OCTA, peripapillary vessel density was significantly lower in all quadrants in the glaucoma group. The significance of these between-group differences was maintained when patients were stratified by visual field mean deviation. Conclusions This is the first comparative analysis of optic disc morphology between glaucoma and pituitary macroadenoma using combined OCT and OCTA. The results yielded lower peripapillary RNFL thickness, lower rim area, and lower peripapillary vessel density in the glaucoma group. These parameters may aid in the initial differentiation between these two optic neuropathies.

Retinal Structure Abnormalities in Parkinson's Disease and Atypical Parkinsonism.

We investigated retinal structure changes in patients with Parkinson's disease (PD), multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and controls, and explored the value of this method in differential diagnosis. Spectral domain optical coherence tomography (SD-OCT) was used to measure peripapillary retinal nerve fiber layer (pRNFL) thickness, and macular thickness and volume. PSP patients showed higher temporal pRNFL thickness than PD and MSA patients. Peripapillary RNFL thickness could be used for discriminating PSP from MSA and PD. PD and MSA patients showed retinal thinning in the foveal center circle and nasal inner sectors compared to controls. Macular thickness and volume could be used for discriminating MSA from PD. There were negative correlations between disease duration and OCT parameters in PD, MSA, and PSP, independent of age, sex ratio, and the side of the eye. PD and atypical parkinsonism correlate with specific patterns of retina alterations. OCT could be a biomarker for differential diagnosis and progression evaluation of parkinsonian syndrome.

Retinal nerve fiber layer thinning as a novel fingerprint for cardiovascular events: results from the prospective cohorts in UK and China

BackgroundRetinal structural abnormalities have been found to serve as biomarkers for cardiovascular disease (CVD). However, the association between retinal nerve fiber layer (RNFL) thickness and the incidence of CVD events remains inconclusive, and relevant longitudinal studies are lacking. Therefore, we aimed to examine this link in two prospective cohort studies.MethodsA total of 25,563 participants from UK Biobank who were initially free of CVD were included in the current study. Another 635 participants without retinopathy at baseline from the Chinese Guangzhou Diabetes Eye Study (GDES) were adopted as the validation set. Measurements of RNFL thickness in the macular (UK Biobank) and peripapillary (GDES) regions were obtained from optical coherence tomography (OCT). Adjusted hazard ratios (HRs), odd ratios (ORs), and 95% confidence intervals (CI) were calculated to quantify CVD risk.ResultsOver a median follow-up period of 7.67 years, 1281 (5.01%) participants in UK Biobank developed CVD events. Each 5-μm decrease in macular RNFL thickness was associated with an 8% increase in incident CVD risk (HR = 1.08, 95% CI: 1.01–1.17, p = 0.033). Compared with participants in the highest tertile of RNFL thickness, the risk of incident CVD was significantly increased in participants in the lowest thickness tertile (HR = 1.18, 95% CI: 1.01–1.38, p = 0.036). In GDES, 29 (4.57%) patients developed CVD events within 3 years. Lower average peripapillary RNFL thickness was also associated with a higher CVD risk (OR = 1.35, 95% CI: 1.11–1.65, p = 0.003). The additive net reclassification improvement (NRI) was 21.8%, and the absolute NRI was 2.0% by addition of RNFL thickness over the Framingham risk score. Of 29 patients with incident CVD, 7 were correctly reclassified to a higher risk category while 1 was reclassified to a lower category, and 21 high risk patients were not reclassified.ConclusionsRNFL thinning was independently associated with increased incident cardiovascular risk and improved reclassification capability, indicating RNFL thickness derived from the non-invasive OCT as a potential retinal fingerprint for CVD event across ethnicities and health conditions.Trial registrationISRCTN 15853192

Effect of nutritional-deficiency anemia on peripapillary retinal nerve fiber layer: A North Indian study.

The purpose of this study was to evaluate the effect of nutritional-deficiency anemia (NDA) on peripapillary retinal nerve fiber layer thickness (PPRNFLT) using spectral-domain optical coherence tomography and to determine any correlation arising thereof. This was a single-center, cross-sectional, observational study. A total 115 eyes of 115 NDA patients (50 of each with iron-deficiency anemia [IDA] and Vitamin B12-deficiency anemia [BDA], and 15 with folic acid-deficiency anemia [FDA]) aged 18-65 years were compared with a total 100 eyes of 50 age- and sex-matched healthy controls. All subjects underwent comprehensive clinical, ophthalmic, and hematological evaluation, followed by PPRNFLT assessment for the mean total, superior, inferior, nasal, and temporal quadrants. PPRNFLT for the mean total and all four quadrants in IDA patients, for the mean total, inferior, nasal, and temporal quadrants in BDA patients, and for the mean total, inferior, and nasal quadrants, in FDA patients, was significantly lower as compared to the controls (P < 0.05). The mean total PPRNFLT of all NDA patients correlated significantly (P < 0.05) with their relevant hematological parameters with Pearson's coefficient (r) value of 0.613, 0.610, 0.336, 0.295, 0.337, 0.374, and - 0.509, respectively, for serum haemoglobin (Hb), iron, ferritin, mean corpuscular volume (MCV), mean cell hemoglobin, mean corpuscular hemoglobin concentration, and total iron binding capacity in IDA; 0.310, 0.435, and - 0.386, respectively, for serum Hb%, Vitamin B12, and MCV in BDA; and 0.557, 0.358, and - 0.294 for Hb%, folate, and MCV, respectively, in FDA cases. Mean total retinal nerve fiber layer thinning of all NDA patients showed progression with the increasing severity grades of anemia, except in very severe BDA where an inverse relationship was documented. Our study revealed that PPRNFLT is significantly thinner in all NDA patients (total and all four quadrants in IDA; total, inferior, nasal, and temporal in BDA; and total, inferior, and nasal in FDA) correlating well with their relevant hematological parameters. Early detection of this may be crucial in preventing potential blinding sequelae and differentiating glaucomatous and other neuro-ophthalmic disorders.

Global and sectoral retinal nerve fiber layer thickness in glaucoma suspects and primary open-angle glaucoma patients attending a tertiary care center in South India

ABSTRACT Background: Spectral-domain optical coherence tomography (OCT) can identify the presence of localized glaucomatous structural damage. The peripapillary retinal nerve fiber layer (RNFL) thickness is a popular OCT parameter used for glaucoma diagnosis and monitoring progression. Aim: To measure the peripapillary RNFL thickness, the pattern of RNFL defect, and association of RNFL with the severity of glaucoma using Spectralis Spectral Domain – OCT in patients with primary open-angle glaucoma (POAG) at a glaucoma clinic in a tertiary care teaching hospital in south India. Methods: Cross-sectional study design. Peripapillary RNFL thickness of 109 glaucomatous eyes of 56 patients aged 40–75 years having POAG, ocular hypertension, or suspected to have glaucoma but without visual field (VF) defects were included in the study. The cross-sectional thickness of RNFL using a 3.46 mm circle centered around the disc in 6 segments were measured and defects in the RNFL were identified by comparing measurements from each patient with the normative database. Results: The study included 109 eyes with 51 (46.79%) preperimetric eyes and 58 (53.21%) POAG eyes (with field defects). The average global thickness in the study population was 91.31 ± 12.81 µm for preperimetric eyes and 67.76 ± 17.33 µm for eyes with glaucoma. There was significant thinning in all segments between eyes with POAG and normal eyes with the mean difference highest in the inferotemporal segment (mean difference of 73.05) and the superotemporal segment (mean difference of 55.85). The global RNFL thickness had a coefficient of − 0.015 (standard error [SE] 0.003, 95% confidence interval [CI]: 0.02–0.009, R2 = 0.29) for mild glaucoma, −0.010 (SE 0.004, 95% CI: 0.02–0.003, R2 = 0.12) for moderate and − 0.18 (SE: 0.001, 95% CI: 0.022–0.014, R2 = 0.60) for severe glaucoma compared to preperimetric eyes in a linear regression model that adjusted for age and gender. Global and sector-wise RNFL thickness also had a significant area under Receiver Operator Characteristic (0.84, 95% CI: 0.78. 0.91) that showed the ability to discriminate between preperimetric and glaucomatous eyes. Possible “floor effect” of RNFL thickness was shown by 7 eyes with advanced glaucoma cases. Conclusion: RNFL thinning can be used as a parameter to assess glaucomatous structural loss that can aid in early diagnosis and monitoring of disease progression, to grade the severity of the disease in primary open-angle glaucoma, and when VFs cannot be done.