Spectral-domain Optical Coherence Tomography Parameters Research Articles

Evaluation of Optic Nerve Head Microcirculation in Open-Angle Glaucoma Patients with Unilateral Visual Field Defect

Introduction: Microcirculation of optic nerve head (ONH) in open-angle glaucoma (OAG) patients with unilateral visual field (VF) loss has yet to be fully investigated, especially the perimetrically unaffected fellow eyes. Methods: Thirty-eight OAG patients with VF defect in one eye and normal VF in the other eye, and thirty-one healthy participants were analyzed. All participants underwent laser speckle flowgraphy (LSFG), spectral-domain optical coherence tomography (SD-OCT) imaging, and VF test for further analyses. LSFG measurements included mean blur rate in all area of ONH (MA), big vessel area of ONH (MV), and tissue area of ONH (MT). SD-OCT parameters included circumpapillary retinal nerve fiber layer (cpRNFL) thickness and macula thicknesses. The difference of LSFG and SD-OCT indices between glaucoma patients and healthy controls were compared. The diagnostic accuracy was analyzed with the areas under the receiver operating characteristic curves (AROCs). Results: Global cpRNFL thickness and macular thickness in unaffected eyes of OAG patients were higher than their fellow eyes and lower than healthy eyes. MA and MV in healthy eyes and unaffected eyes were significantly higher than in affected eyes. MT in unaffected eyes of OAG patients was higher than in their fellow affected eyes but lower than in healthy eyes. The AROCs were highest for cpRNFL (0.925), followed by macular thickness (0.838), and MT (0.834). Conclusions: ONH microcirculation in perimetrically unaffected fellow eyes was decreased in OAG patients with unilateral VF loss. LSFG can detect changes of ONH in high-risk eyes before detectable VF damage, which may reflect the vascular pathophysiology for glaucoma.

Genotype-Phenotype Associations in an X-Linked Retinoschisis Patient Cohort: The Molecular Dynamic Insight and a Promising SD-OCT Indicator.

This study investigated a three-dimensional indicator in spectral-domain optical coherence tomography (SD-OCT) and established phenotype-genotype correlation in X-linked retinoschisis (XLRS). Thirty-seven patients with XLRS underwent comprehensive ophthalmic examinations, including visual acuity (VA), fundus examination, electroretinogram (ERG), and SD-OCT. SD-OCT parameters of central foveal thickness (CFT), cyst cavity volume (CCV), and photoreceptor outer segment length were assessed. CCV was defined as the sum of the areas of cyst cavities in uential B-scans, measured automatically by self-developed software (OCT-CCSEG). Structural changes of the protein associated with missense variants were quantified by molecular dynamics (MD). The correlation between genotype and phenotype was analyzed. Twenty-seven different RS1 variants were identified, including a novel variant c.336_337insT(p.L113Sfs*8). The average age of onset was 14.76 ± 15.75years, and the mean VA was 0.84 ± 0.43 logMAR. The mean CCV was 1.69 ± 1.87mm3, correlating significantly with CFT (R = 0.66; P < 0.01). In the genotype-phenotype analysis of missense variants, CCV significantly correlated with the structural effect on the protein of mutational changes referred to as wild type, including root-mean-square deviation (R = 0.34; P = 0.04), solvent accessible surface area (R = 0.38; P = 0.02), and surface hydrophobic area (R = 0.37; P = 0.03). The amplitude of scotopic 3.0 ERG a-waves and b-waves significantly correlated with the percentage change of the β-strand in the secondary structure (a-wave: R = -0.58, P < 0.01; b-wave: R = -0.53, P < 0.01). CCV is a promising indicator to quantify the structural disorganization of XLRS retina. The OCT-CCSEG software calculated CCV automatically, potentially facilitating prognosis assessment and development of personalized treatment. Moreover, MD-involved genotype-phenotype analysis suggests an association between protein structural alterations and XLRS severity measured by CCV and ERG.

Morphological Biomarkers Related to Visual Acuity in Patients With Radiation Retinopathy Treated With Intravitreal Ranibizumab.

Our objective was to monitor variables via spectral-domain optical coherence tomography (SD-OCT) and identify the most relevant biomarkers related to best-corrected visual acuity (BCVA) in radiation retinopathy (RR). A post-hoc analysis of the two-year Ranibizumab for Radiation Retinopathy (RRR) trial analyzed vision and OCT parameters including intraretinal fluid, ellipsoid zone (EZ) disruption, retinal pigment epithelium atrophy, hard exudates, retinal hemorrhage, retinal neovascularization, and subfoveal fluid. BCVA and SD-OCT parameters were evaluated by univariate analysis and a mixed-effects model. Forty eyes from the RRR trial were included. Intraretinal cyst vertical size (week 24: P = 0.032; week 48: P = 0.021), neovascularization (week 48: P = 0.028; week 72: P = 0.025), and EZ disruption (week 72: P = 0.029; week 104: P = 0.019) were the clinical parameters most relevant to BCVA by univariate analysis in at least two time points. The mixed-effects model confirmed the relevance of intraretinal cyst vertical size (P = 0.001) and neovascularization (P = 0.001) but not EZ disruption (P = 0.119) over the course of the study. This study characterizes the course of visual loss in RR by identifying intraretinal cyst vertical size, neovascularization, and EZ disruption as biomarkers of poor BCVA over a span of two years. Larger multicenter studies are needed to confirm these findings. [Ophthalmic Surg Lasers Imaging Retina 2024;55:255-262.].

Is Primary Open-Angle Glaucoma a Vascular Disease? Assessment of the Relationship between Retinal Arteriolar Morphology and Glaucoma Severity Using Adaptive Optics.

Retinal vascular abnormalities may be associated with glaucomatous damage. Adaptive optics (AO) is a new technology that enables the analysis of retinal vasculature at the cellular level in vivo. The purpose of this study was to evaluate retinal arteriolar parameters using the rtx1 adaptive optics fundus camera (AO-FC) in patients with primary open-angle glaucoma (POAG) at different stages and to investigate the relationship between these parameters and changes in spectral-domain optical coherence tomography (SD-OCT) and perimetry. Parameters of the retinal supratemporal and infratemporal arterioles (wall thickness (WT), lumen diameter (LD), total diameter (TD), wall-to-lumen ratio (WLR), and cross-sectional area of the vascular wall (WCSA)) were analysed with the rtx1 in 111 POAG eyes, which were divided into three groups according to the severity of the disease, and 70 healthy eyes. The associations between RTX1 values and the cup-to-disk ratio, SD-OCT parameters, and visual field parameters were assessed. Compared with the control group, the POAG groups showed significantly smaller TD and LD values (p < 0.05) and significantly higher WLR and WT values (p < 0.05) for the supratemporal and infratemporal arterioles. TD was significantly positively correlated with the retinal nerve fibre layer (RNFL) and ganglion cell complex (GCC) (p < 0.05). LD was significantly positively correlated with the RNFL, GCC, and rim area (p < 0.05). The WLR was significantly negatively correlated with the RNFL, GCC, rim area, and MD (p < 0.05), while it was significantly positively correlated with the cup-to-disc ratio and PSD (p < 0.05). The results suggest that vascular dysfunction is present in POAG, even at a very early stage of glaucoma, and increases with the severity of the disease.

New keratoconus staging system based on OCT.

To establish a numerical spectral-domain optical coherence tomography (SD-OCT)-based keratoconus (KC) staging system and compare it with existing KC staging systems. Eye Hospital of Wenzhou Medical University, Wenzhou, China. Retrospective case-control study. Scheimpflug tomography, air-puff tonometry, and SD-OCT were performed on 236 normal and 331 KC eyes. All SD-OCT-derived parameters of the corneal epithelium and stroma were evaluated based on their receiver operating characteristic (ROC) curves, area under the curve (AUC), sensitivity, and specificity to discriminate between normal and KC eyes. The best performing parameters were subsequently used to create an OCT-based staging system, which was compared with existing tomographic and biomechanical staging systems. 236 eyes from 236 normal patients and 331 eyes from 331 KC patients of different stages were included. The highest ranked AUC ROC SD-OCT parameters, derived from stroma and epithelium, were stroma overall minimum thickness (ST: AUC 0.836, sensitivity 90%, specificity 67%) and epithelium overall SD (EP: AUC 0.835, sensitivity 75%, specificity 78%). A numerical SD-OCT staging system called STEP including 2 parameters-"ST" and "EP"-with 5 stages was proposed. The new SD-OCT-based KC staging system is the first to take the epithelium with its sublayer stroma information into account, showing a strong agreement to the existing staging systems. This system could be incorporated into daily practice, potentially leading to an overall improvement in KC treatment and follow-up management.

Classifying glaucoma exclusively with OCT: comparison of three clustering algorithms derived from machine learning.

To objectively classify eyes as either healthy or glaucoma based exclusively on data provided by peripapillary retinal nerve fiber layer (pRNFL) and ganglion cell-inner plexiform (GCIPL) measurements derived from spectral-domain optical coherence tomography (SD-OCT) using machine learning algorithms. Three clustering methods (k-means, hierarchical cluster analysis -HCA- and model-based clustering-MBC-) were used separately to classify a training sample of 109 eyes as either healthy or glaucomatous using solely 13 SD-OCT parameters: pRNFL average and sector thicknesses and GCIPL average and minimum values together with the six macular wedge-shaped regions. Then, the best-performing algorithm was applied to an independent test sample of 102 eyes to derive close estimates of its actual performance (external validation). In the training sample, accuracy was 91.7% for MBC, 81.7% for k-means and 78.9% for HCA (p value = 0.02). The best MBC model was that in which subgroups were allowed to have variable volume and shape and equal orientation. The MBC algorithm in the independent test sample correctly classified 98 out of 102 cases for an overall accuracy of 96.1% (95% CI, 92.3-99.8%), with a sensitivity of 94.3 and 100% specificity. The accuracy for pRNFL was 92.2% (95% CI, 86.9-97.4%) and for GCIPL 98.0% (95% CI, 95.3-100%). Clustering algorithms in general (and MBC in particular) seem promising methods to help discriminate between healthy and glaucomatous eyes using exclusively SD-OCT-derived parameters. Understanding the relative merits of one method over others may also provide insights into the nature of the disease.

Does Subretinal Fluid Optical Density Ratio Differ Among the Eyes with Acute Central Serous Chorioretinopathy,Vogt Koyanagi Harada Disease and Choroidal Hemangioma: A Cross-sectional Study

PurposeTo investigate the diagnostic value of optical density ratio (ODR) in various diseases with subretinal fluid (SRF) due to different pathophysiologies. MethodsPatients with acute central serous chorioretinopathy, CSCR (n = 49), Vogt Koyanagi Harada disease, VKH (n = 34), and choroidal hemangioma (n = 17) characterized with SRF were included. Spectral-domain optical coherence tomography (SD-OCT) images were analyzed using ImageJ by three independent readers. The ODRs were calculated using “region of interest (ROI)” and “entire region (TOTAL)” selection methods from the SRF to the vitreous, retinal nerve fiber layer (RNFL), and retinal pigment epithelium (RPE) reflectivity ratios. A correlation analysis between age, central macular thickness (CMT), SRF height, SRF width, and ODRs were obtained. ResultsOptical density (OD) measurement was highly reproducible (intraclass correlation coefficient> 0.9). Optical density of the SRF, vitreous, RNFL, and signal strength were comparable (p = 0.360, p = 0.247, p = 0.105, and 0.628, respectively). There was no difference in SRF OD measurements between the two methods (p = 0.401), while there was a significant difference in vitreous OD measurements (p = 0.016). ANOVA test of ODR(ROI), ODR(TOTAL), ODR-RPE (ROI) and ODR-RNFL (ROI) revealed no significant difference among acute CSCR, VKH disease and choroidal hemangioma groups (p > 0.05 for all). Correlation analysis revealed a significant negative correlation between SRF height (p < 0.05) and CMT (p < 0.01) with SRF ODR(ROI). ConclusionODR measurement appears to be a highly repeatable SD-OCT parameter for diseases characterized with SRF collection. Despite variations in their pathophysiology, the ODR was not statistically different in acute CSCR, VKH disease, and choroidal hemangioma.

Quantification of retinal ganglion cell loss in patients with homonymous visual field defect due to stroke.

To quantify the degree of ganglion cell degeneration through spectral domain optical coherence tomography (SD-OCT) in adult patients with post-stroke homonymous visual field defect. Fifty patients with acquired visual field defect due to stroke (mean age = 61years) and thirty healthy controls (mean age = 58years) were included. Mean deviation (MD) and pattern standard deviation (PSD), average peripapillary retinal nerve fibre layer thickness (pRNLF-AVG), average ganglion cell complex thickness (GCC-AVG), global loss volume (GLV) and focal loss volume (FLV) were measured. Patients were divided according to the damaged vascular territories (occipital vs. parieto-occipital) and stroke type (ischaemic vs. haemorrhagic). Group analysis was conducted with ANOVA and multiple regressions. pRNFL-AVG was significantly decreased among patients with lesions in parieto-occipital territories compared to controls and to patients with lesions in occipital territories (p = .04), with no differences with respect to stroke type. GCC-AVG, GLV and FLV differed in stroke patients and controls, regardless of stroke type and involved vascular territories. Age and elapsed time from stroke had a significant effect on pRNFL-AVG and GCC-AVG (p < .01), but not on MD and PSD. Reduction of SD-OCT parameters occurs following both ischaemic and haemorrhagic occipital stroke, but it is larger when the injury extends to parietal territories and increases as time since stroke increases. The size of visual field defect is unrelated to SD-OCT measurements. Macular GCC thinning appeared to be more sensitive than pRNFL in detecting retrograde retinal ganglion cell degeneration and its retinotopic pattern in stroke.

Macular morphological changes in retinal vein occlusion with macular involvement and their association with macular ischemia

Aim: The aim is to study the association between macular morphological changes and macular ischemia in retinal vein occlusion (RVO) involving macula by spectral domain-optical coherence tomography (SD-OCT). Settings and Design: Observational cross-sectional study. Materials and Methods: The study included a total of 31 eyes of 30 RVO patients involving macula divided into two groups on the basis of fundus fluorescein angiography: Group A (RVO with macular ischemia) and Group B (RVO without macular ischemia). In each patient, macular cube and horizontal HD raster scans of the macula were performed to evaluate quantitative (central foveal thickness [CFT]) and qualitative (loss of inner retinal layers, loss of foveal inner segment/outer segment [IS/OS] junction, and prominent middle-limiting membrane [p-MLM] sign) macular morphological changes, respectively. Statistical Analysis: The continuous and categorical data were analyzed using unpaired t-test and Fisher’s exact test, respectively, with GraphPad Prism 9 software. Results: The mean CFT was thinner in Group A (432.71 ± 172.30 µm) as compared to Group B (564.57 ± 151.16 µm) and the difference between the two groups was statistically significant (P &lt; 0.05). In this study, we found that the loss of inner retinal layer and loss of foveal IS/OS junction were more commonly associated with the macular ischemia group and this difference was statistically significant P = 0.0245 and 0.0292, respectively. We did not find any significant relationship between p-MLM sign with macular ischemia. Conclusion: SD-OCT parameters such as CFT, loss of inner retinal layer, and loss of foveal IS/OS junction were observed to predict macular ischemia to some extent.

Huntington’s disease and neurovascular structure of retina

Retinal biomarkers in neurodegenerative disorders have attracted much attention in recent years. Recent studies have reported visual dysfunction in Huntington's disease (HD). However, little is known about retinal structural changes in HD. A total of 50 subjects, including 25 motor-manifest HD patients and 25 gender- and age-matched controls, were enrolled. Unified Huntington's Disease Rating Score-Motor part was assessed in HD patients. Spectral-domain Optical Coherence Tomography (SD-OCT) was used to evaluate the macular thickness and peripapillary retinal nerve fiber layer (pRNFL). Superficial and deep capillary plexus densities were measured using OCT angiography (OCTA). To account for inter-eye correlation, generalized estimating equation (GEE) model was used. HD patients had a significant reduction in macular thickness in both inner and outer superior sectors and the inferior outer sector. Inferior pRNFLs were significantly decreased in thickness. There was no significant difference in retinal capillary plexus density between the two groups. Age and disease duration were negatively correlated with macular thickness in HD patients. However, the severity of motor involvement was not correlated with SD-OCT or OCTA parameters. We observed attenuated pRNFL and macular retinal thickness in patients with HD, independent of macular capillary plexus parameters. It can support the hypothesis that the retina may be a potential biomarker for monitoring the neurodegenerative process in HD.

Predictive value of ectopic inner foveal layer without internal limiting membrane peeling for idiopathic epiretinal membrane surgery

To investigate the clinical importance of ectopic inner foveal layer(EIFL) grading (mild to severe) in patients diagnosed with idiopathic epiretinal membrane (iERM) and had pars plana vitrectomy (PPV) with solely ERM peeling. Patients diagnosed with iERMs who had undergone PPV including only ERM peeling were enrolled in the study, and follow-up findings were recorded at baseline, and at 3, 6, 12months and final examinations. EIFL was categorized into four grades, from mild to severe. Pre- and postoperative anatomical changes were measured using spectral domain optical coherence tomography (SD-OCT) imaging. The association between EIFL and other SD-OCT parameters with best-corrected visual acuity (BCVA) was assessed before and after PPV surgery. One-hundred thirty-eight eyes of 106 patients with mild to severe EIFL were included in the study. Higher EIFL thickness was significantly correlated with lower baseline (r = 0.575, p = 0.020) and final BCVA (r = 0.748, p = 0.001). Although EIFLs continued in advanced-stage cases (stage 3 and 4) (64 eyes [82%]) at the final visit, it was observed in 8 eyes (23%) in the early stage (stage 2) of iERMs. A strong positive correlation was found between EIFL thickness and recurrence rate of ERM (r = 0.876, p < 0.001). Recurrence of ERM was detected in 27 eyes; 2 (7%) at stage 1, 3 (9%) at stage 2, 10 (23%) in stage 3, and 12 (33%) in stage 4 (p < 0.001). A negative association was found between the severity of EIFL and postoperative anatomical and visual recovery. In terms of surgical timing, early stages (stages 1 and 2) may be preferred for providing good anatomical and visual recovery and a low recurrence rate following surgery.

Sex variation of central serous chorioretinopathy by spectral domain optical coherence tomography

Purpose The aim of this study was to compare the spectral domain optical coherence tomography (SD-OCT) characteristics of central serous chorioretinopathy (CSR) between male and female patients.Patients and methods This is a retrospective study that included 39 patients of both sexes diagnosed as CSR during the period between January 2018 and May 2020. The analyzed data included patients’ age, duration of symptoms, and the SD-OCT measurable parameters in the male and female patient groups. The SD-OCT parameters included central total retinal thickness, central sensory retinal thickness, vertical distance of subfoveal subretinal fluid, horizontal distance of subfoveal subretinal fluid, and the presence of subretinal deposits. These parameters were compared and statistically analyzed between the two groups.Results The study included 24 male patients and 15 female patients. The mean age was 35.33±9.88 years in the male group and 41.53±8.28 years in the female group (P=0.05). In the male group, central total retinal thickness, central sensory retinal thickness, vertical distance of subfoveal subretinal fluid, and horizontal distance of subfoveal subretinal fluid were 448±93 μm, 182±34 μm, 305±53 μm, and 3.07±0.63 mm, respectively, while in the female group, they were 346±127 μm (P=0.006), 178±34 μm (P=0.73), 244±61 μm (P=0.002), and 2.34±0.67 mm (P=0.001), respectively. The percentage of patients having subretinal deposit was significantly more in the male group than in the female group (P=0.003).Conclusions There was a statistically significant difference in SD-OCT characteristics of CSR between male and female patients. Further studies are needed regarding the persistence of these OCT differences after treatment of CSR.

External Limiting Membrane Disruption Predicts Long-Term Outcome in Strict Treat-And-Extend Regimen in Neovascular Age-Related Macular Degeneration.

The use of anti-vascular-endothelial growth factor agents for neovascular age-related macular degeneration (nAMD) in different treatment schemes is widely common in clinical practice. However, there is currently limited data on the long-term outcomes of a strict treat-and-extend regimen (TER) and imaging biomarkers to predict both functional outcome and the potential for a TER exit due to success. In this retrospective study we followed treatment-naïve subjects with nAMD starting treatment with either ranibizumab or aflibercept in a TER without loading dose but with predefined exit criteria for up to 8 years. We evaluated both the functional outcome and several spectral-domain optical coherence tomography parameters in a follow-up mode using a standardized protocol. Within the 211 eyes followed for a mean of 60.3 ± 20.9 months, follow-up adherence was high with major part of discontinuations of TER being due to success. Mean best-corrected visual acuity (BCVA) increased from initially 63.9 ± 15.5 ETDRS letters to 70.0 ± 14.7 after 1 year (+6.1 letters, p < 0.001) and to 68.5 ± 18.1 (+4.6 letters, p = 0.028) at 5 years. A worse BCVA (p = 0.001) and a better external limiting membrane (ELM) disruption score at baseline predicted (p = 0.019) BCVA gain at 5 years. The probability of reaching the exit criteria was significantly associated with a better ELM disruption score (p = 0.044) and the absence of a central pigment epithelial detachment (PED) (p = 0.05) at baseline. Significant visual gains were sustained in a long-term TER in a real-world setting. Integrity of ELM at baseline predicted BCVA gain at 5 years and the potential for TER exit due to success.

Foveal and Extrafoveal Effects of Half-Dose Photodynamic Therapy in Chronic Central Serous Chorioretinopathy: A Cohort Study

ABSTRACT Purpose:To compare the efficacy and safety of foveal and extrafoveal half-dose photodynamic therapy (HD-PDT) for chronic Central Serous Chorioretinopathy (cCSC). Methods: This retrospective, cohort study included cCSC eyes submitted to HD-PDT on foveal (F) or extrafoveal (E) areas. Patients were evaluated at baseline and 12 weeks after treatment for best corrected visual acuity (BCVA) and the following spectral-domain optical coherence tomography (SD-OCT) subfoveal parameters: central macular thickness (CMT), outer nuclear layer, external limiting membrane, ellipsoid zone, interdigitation zone, choroidal thickness and subretinal fluid (SRF). Results: F group comprised 33 eyes (47.1%) and E group comprised 37 eyes (52.9%). Both groups showed an improvement of BCVA after HD-PDT with no significant differences in final BCVA (p = .41). CMT and SRF showed a significant improvement after HD-PDT in both groups, but the rate of disruption of the external retinal layers remained stable. During follow-up, SD-OCT parameters and the rate of anatomical success showed no significant differences regarding the treatment location. No major sequelae were noticed. Conclusion: Foveal and extrafoveal applications of HD-PDT for cCSC showed comparable efficacy and safety.

Structure-Function Mapping Using a Three-Dimensional Neuroretinal Rim Parameter Derived From Spectral Domain Optical Coherence Tomography Volume Scans.

PurposeTo assess the structure-function relationship in glaucoma using Humphrey visual field (HVF) perimetry and a three-dimensional neuroretinal rim parameter derived from spectral domain optical coherence tomography (SD-OCT) volume scans.MethodsStructure-function correlation was analyzed globally and regionally (four quadrants and four sectors). Structural data included peripapillary retinal nerve fiber layer (RNFL) thickness and minimum distance band (MDB) neuroretinal rim thickness, defined as the shortest distance between the inner cup surface and the outer retinal pigment epithelium/Bruch's membrane complex. Logarithmic regression analyses were performed and Pearson correlation coefficients determined to assess relationship strength.ResultsThe study consisted of 102 open-angle glaucoma patients and 58 healthy subjects. The Pearson correlation coefficient for global MDB thickness (R = 0.585) was higher than for global RNFL thickness (R = 0.492), but the difference was not statistically significant (P = 0.18). The correlation coefficients for regional MDB thicknesses and corresponding HVF sensitivities were higher than those for regional RNFL thicknesses and HVF in six out of eight regions (P = 0.08 to 0.47). In the remaining two out of eight regions, the correlation coefficients were higher for RNFL thickness than for MDB thickness (P = 0.15 to 0.20).ConclusionsThree-dimensional MDB neuroretinal rim thickness relates to visual function as strongly as the most commonly used SD-OCT parameter for glaucoma, two-dimensional peripapillary RNFL thickness.Translational RelevanceThis paper illustrates the potential for 3D OCT algorithms to improve in vivo imaging in glaucoma.

ASSESSMENT OF EARLY CHANGES IN SPECTRAL DOMAIN-OPTICAL COHERENCE TOMOGRAPHY AFTER INITIATION OF TREATMENT WITH INTRAVITREAL AFLIBERCEPT (EYLEA) OVER A 12-WEEK PERIOD FOR PATIENTS WITH NEOVASCULAR AGE-RELATED MACULAR DEGENERATION: A Multicenter French Study (START).

To assess early changes in spectral-domain optical coherence tomography during the loading phase with intravitreal aflibercept therapy in patients with neovascular age-related macular degeneration. In this prospective, open-label, single-arm, multicenter study, patients with neovascular age-related macular degeneration, who were antivascular endothelial growth factor treatment-naïve, received three monthly initial doses of intravitreal aflibercept 2 mg. The primary outcome was the proportion of patients with dry spectral-domain optical coherence tomography at 12 weeks, defined as an absence of intraretinal edema, intraretinal cysts, subretinal fluid, and subretinal pigment epithelium fluid. Fifty eyes of 50 patients were investigated. At 12 weeks, 34.0% (17/50) had dry spectral-domain optical coherence tomography. Marked reductions were observed for all other spectral-domain optical coherence tomography parameters. The mean macular central thickness fell significantly from 463.2 ± 184.3 µm at baseline to 288.9 ± 76.8 µm at Week 12 (P < 0.0001). The mean best-corrected visual acuity also improved significantly from 61.0 ± 16.0 letters at baseline to 66.6 ± 19.0 letters at Week 12 (P = 0.0006). The anatomic and functional outcomes improved over the 12-week study period. All outcome variables peaked after the third aflibercept injection, confirming the benefit of three initial doses.

Predictors for 2-Year Functional and Morphological Outcomes of a Treat-and-Extend Regimen with Ranibizumab in Patients with Diabetic Macular Edema

Purpose: The purpose of the study was to investigate longer term functional and morphological outcomes and their predictors in diabetic macular edema (DME) following a treat-and-extend regimen (TER) without loading dose under ranibizumab. Methods: Patient data were reviewed and analyzed retrospectively over a period of 24 months after initiation of TER. Best-corrected visual acuity (BCVA), treatment frequency, and quantitative and qualitative spectral-domain optical coherence tomography parameters were assessed. Results: 118 eyes of 87 patients were included. A mean of 9.74 ± 2.13 injections in the first and 7.63 ± 2.29 in the second year were applied. There were significant gains of BCVA and reductions in central retinal thickness from baseline to 12 and 24 months (all p < 0.001). Percentage of eyes with an intact inner segment/outer segment (IS/OS) junction increased from 15.3% at baseline to 42.1% at 24 months (p < 0.001). An intact IS/OS junction at baseline increased the probability of having a dry retina after 12 months by 79.3% (p = 0.017) and after 24 months by 88.1% (p = 0.040). Less IS/OS disruption at baseline predicted longer maximum recurrence-free treatment intervals at 2 years (r = −0.345, p < 0.001) and better BCVA at 1 year (r = −0.347, p < 0.001). Baseline bigger intraretinal cysts were associated with more IS/OS disruption at 24 months (r = 0.305, p = 0.007). Younger age and lower BCVA at baseline were predictive for a higher BCVA gain at 24 months (p = 0.046, p < 0.001). Conclusion: Ranibizumab applied in a TER without loading dose in DME significantly improves visual acuity and retinal anatomical structure throughout 2 years. The evaluated predictors might help guide routine clinical treatment in DME.

Investigation of macular and optic nerve head structural changes using spectral domain optical coherence tomography in internal carotid artery stenosis

To demonstrate differences in optic nerve head (ONH), retinal nerve fiber layer (RNFL), and macular thickness in patients with internal carotid artery (ICA) stenosis using spectral domain optical coherence tomography (SD-OCT). A case-controlled study was conducted in 31 patients with a diagnosis of unilateral ICA stenosis (the percentage of stenosis was between 65 and 85%), and 53 age- and sex-matched healthy subjects (control group) from March 2016 to April 2018. The ONH parameters, RNFL, and macular thicknesses in the nine macular quadrants according to the Early Treatment Diabetic Retinopathy Study (ETDRS) were measured using SD-OCT. The average macular thickness and outer macular quadrants measurements were lower in the ICA stenosis group (P < 0.05). The thickness of the fovea and inner macular quadrants was similar in healthy and patient eyes. Similarly, the ONH and RNFL profiles based on SD-OCT parameters were similar between the groups. There was a negative weak correlation between mean macular and RNFL thicknesses and the duration and percentage of ICA stenosis. The average macular thickness and measurements of outer macular quadrants in the ICA stenosis group were lower than in the control group. Macular changes may occur before symptomatic ocular ischemic syndrome (OIS). SD-OCT macular measurements may be beneficial in the early detection of OIS due to ICA stenosis.

Utility of Spectral-Domain Optical Coherence Tomography in Differentiating Papilledema From Pseudopapilledema: A Prospective Longitudinal Study.

Prospective and longitudinal studies assessing the utility of spectral-domain optical coherence tomography (SD-OCT) to differentiate papilledema from pseudopapilledema are lacking. We studied the sensitivity and specificity of baseline and longitudinal changes in SD-OCT parameters with 3D segmentation software to distinguish between papilledema and pseudopapilledema in a cohort of patients referred for evaluation of undiagnosed optic disc elevation. Fifty-two adult patients with optic disc elevation were enrolled in a prospective longitudinal study. A diagnosis of papilledema was made when there was a change in the appearance of the optic disc elevation on fundus photographs as noted by an independent observer at or before 6 months. The degree of optic disc elevation was graded using the Frisen scale and patients with mild optic disc elevation (Frisen grades 1 and 2) were separately analyzed. SD-OCT parameters including peripapillary retinal nerve fiber layer (pRNFL), total retinal thickness (TRT), paracentral ganglion cell layer-inner plexiform layer (GCL-IPL) thickness, and optic nerve head volume (ONHV) at baseline and within 6 months of follow-up were measured. Twenty-seven (52%) patients were diagnosed with papilledema and 25 (48%) with pseudopapilledema. Among patients with mild optic disc elevation (Frisen grades 1 and 2), baseline pRNFL (110.1 µm vs 151.3 µm) and change in pRNFL (ΔpRNFL) (7.3 µm vs 52.3 µm) were greater among those with papilledema. Baseline and absolute changes in TRT and ONHV were also significantly higher among patients with papilledema. The mean GCL-IPL thickness was similar at baseline, but there was a small reduction in GCL-IPL thickness among patients with papilledema. Receiver operator curves (ROCs) were generated; ΔpRNFL (0.93), ΔTRT (0.94), and ΔONHV (0.95) had the highest area under the curve (AUC). The mean baseline and absolute changes in SD-OCT measurements (pRFNL, TRT, and ONHV) were significantly greater among patients with papilledema, and remained significantly greater when patients with mild optic disc elevation were separately analyzed. ROCs demonstrated that ΔpRNFL, ΔTRT, and ΔONHV have the highest AUC and are best able to differentiate between papilledema and pseudopapilledema.

Reduced minimum rim width of optic nerve head: a potential early marker of retinal neurodegeneration in children and adolescents with type 1 diabetes

AimsTo determine whether early retinal neurodegenerative changes in pediatric patients with type 1 diabetes (T1D) can be detected by spectral domain-optical coherence tomography (SD-OCT) and whether such changes are associated with risk factors for T1D complications. MethodsA total of 147 T1D children/adolescents and 51 healthy controls underwent SD-OCT. Spherical refractive error (SRE), macular total retinal thickness (TRT), ganglion cell layer (GCL), retinal nerve fiber layer (RNFL), minimum rim width (MRW), and Bruch’s membrane opening area (BMOA) were measured. Clinical and biochemical parameters were recorded at the time of SD-OCT and starting at T1D onset. Multiple regression models were calculated using SD-OCT parameters as dependent and risk factors as independent variables. ResultsMRW was significantly thinner in the T1D patients (global MRW:361.58vs386.33 µm; p = 0.009), while RNFL and macular parameters were similar for both groups. MRW was inversely correlated with mean HbA1c (r ≥ -0.180, p < 0.05). Multiple regression showed that part of the variability in MRW was explained by HbA1c and BMOA (R2 = 0.21; p < 0.001), independent of other cardiometabolic risk factors. ConclusionsMRW reduction could be a potential early marker of retinal neurodegeneration detectable in pediatric patients with T1D. The association between MRW and mean HbA1c suggests that glucometabolic control may affect early retinal neurodegeneration starting in childhood.