Optical Coherence Tomography Scans Research Articles

Analysis of OCT Scanning Parameters in AMD and RVO.

Optical coherence tomography (OCT) is an extensively used imaging tool for disease monitoring in both age-related macular degeneration (AMD) and retinal vein occlusion (RVO). However, there is limited literature on minimum requirements of OCT settings for reliable biomarker detection. This study systematically investigates both the influence of scan size and interscan distance (ISD) on disease activity detection. We analyzed 80 OCT volumes of AMD patients and 12 OCT volumes of RVO patients for the presence of subretinal fluid (SRF), intraretinal fluid (IRF), and pigment epithelium detachment (PED). All volume scans had a scan size of 6 × 6 mm and an ISD of 125 µm. We analyzed both general fluid distribution and how biomarker detection sensitivity decreases when reducing scan size or density. We found that in AMD patients, all fluids were nearly normally distributed, with most occurrences in the foveal center and concentric decrease towards the periphery. When reducing the scan size to 3 × 3 and 2 × 2 mm, disease activity detection was still high (0.98 and 0.96). Increasing ISD only slightly can already compromise biomarker detection sensitivity (0.9 for 250 µm ISD against 125 µm ISD).

An automated process for bulk downloading optical coherence tomography scans

ObjectiveTo develop an automated method for efficiently downloading a large number of optical coherence tomography (OCT) scans obtained using the Heidelberg Spectralis (Heidelberg Engineering, Heidelberg, Germany) platform.MethodsThe electronic medical records and OCT scans were extracted for all patients with age-related macular degeneration treated at the Hadassah University Hospital Retina Clinic between 2010 and 2021. A macro was created using Visual Basic for Applications (VBA) and Microsoft Excel to automate the export process and anonymize the OCT scans in accordance with hospital policy. OCT scans were extracted as proprietary Heidelberg E2E files.ResultsThe VBA macro was used to export a total of 94,789 E2E files from 2807 patient records, with an average processing time of 4.32 min per volume scan (SD: 3.57 min). The entire export process took a total of approximately 202 h to complete over a period of 24 days. In a smaller sample, using the macro to download the scans was significantly faster than manually downloading the scans, averaging 3.88 vs. 11.08 min/file, respectively (t = 8.59, p < 0.001). Finally, we found that exporting the files during both off-clinic and working hours resulted in significantly faster processing times compared to exporting the files solely during working hours (t = 5.77, p < 0.001).ConclusionsThis study demonstrates the feasibility of using VBA and Excel to automate the process for bulk downloading data from a specific medical imaging platform. The specific steps and techniques will likely vary depending on the software used and hospital constraints and should be determined for each application.

Long-Term results of macular buckle for MTM stage 3-4 With maculoschisis and macular detachment without and With lamellar macular hole.

To report the long-term anatomical and functional results of macular buckle for Myopic Traction Maculopathy (MTM) in stages 3a, 3b, 4a, and 4b according to the MTM Staging System (MSS). Retrospective observational cohort study involving 55 consecutive patients with MTM in stages 3a, 3b, 4a, and 4b who underwent macular buckle (MB). Postoperative outcomes, including optical coherence tomography (OCT) scans to evaluate the MTM stage and its progression, were evaluated 1-month postoperatively (i.e., "intermediate follow-up") and at last follow-up ranging between 6 and 156 months postoperatively (i.e., "final follow-up"). Fifty-five eyes affected by MTM who underwent MB were enrolled. The mean preoperative and postoperative axial length was 31.13 ± 2.14 and 29.73 ± 2.16 mm, respectively (p < 0.01), with a mean axial shift of 1.32 ± 0.77 mm. The mean sample best corrected visual acuity (BCVA) at baseline, intermediate, and final follow-ups was 0.87 ± 0.36, 0.73 ± 0.31, 0.41 ± 0.32 logMar, respectively (p < 0.01). Foveal and retinal anatomical improvements were achieved in 50 (91%) and 53 (96.4%) eyes at intermediate follow-up, respectively. In the final follow-up, 54 (98.2%) and 55 (100%) eyes showed foveal and retinal anatomical improvements, respectively. MB as a single procedure, when applied to MTM in stages 3a, 3b, 4a, and 4b, leads to significant anatomical and functional improvement. The MTM Staging System allows us to evaluate the best surgical technique and the surgical timing tailored to the different stages to increase the surgery's success and lower the complications of each technique.

Internal Carotid Artery Stenosis and Ipsilateral Subretinal Drusenoid Deposits.

Subretinal drusenoid deposits (SDDs) in age-related macular degeneration (AMD) are strongly associated with vasculopathies such as myocardial infarction and ischemic stroke. This study evaluates ischemic stroke subjects for SDDs to determine whether ocular hypoperfusion from internal carotid artery (ICA) stenosis is associated with ipsilateral SDDs. A cross-sectional study at Mount Sinai Hospital recruited 39 subjects with ischemic stroke (aged 52-90; 18 women, 21 men); 28 completed all study procedures. Computed tomography (CT) of the head and neck evaluated 54/56 ICAs for stenosis criteria: none (n = 33), mild (n = 12), moderate (n = 3), severe (n = 3), and complete (n = 3). Spectral-domain optical coherence tomography (SD-OCT) scans were read to consensus by two masked graders for soft drusen, SDDs and choroidal thickness (CTh; choroidal thinning = CTh < 250µm). Univariate testing was done with Fisher's exact test. Multivariate logistic regression models tested age, gender, and ICA stenosis as covariates. Moderate or more ICA stenosis (≥50%-69%) was significantly associated with ipsilateral choroidal thinning (P = 0.021) and ipsilateral SDDs (P = 0.005); the latter were present distal to six of nine stenosed ICAs versus five of 33 normal ICAs. Mild ICA stenosis (≥1%-49%) was not significantly associated with ipsilateral SDDs. Multivariate regression found that older age (P = 0.015) and moderate or more ICA stenosis (P = 0.011) remained significant independent risks for ipsilateral SDDs. At least moderate ICA stenosis (≥50%-69%) is strongly associated with ipsilateral SDDs and choroidal thinning, supporting downstream ophthalmic artery and choroidal hypoperfusion from ICA stenosis as the mechanism for SDD formation. SDDs may thus serve as sensitive biomarkers for ischemic stroke and other vascular diseases.

Serum and Vitreous Levels of Placenta Growth Factor in Diabetic Retinopathy Patients: Correlation With Disease Severity and Optical Coherence Tomographic Parameters.

Purpose The primary objective of this study was to compare placenta growth factor (PlGF) levels in the serum and vitreous of diabetic retinopathy (DR) patients to non-diabetic controls. Additionally, the study aimed to establish associations between serum and vitreous PlGF concentrations and to examine the correlation between vitreous PlGF in DR patients and morphological parameters. Methods This study included serum and vitreous samples from 38 patients, including 21 patients with DR and 17 non-diabetic controls. The control group included non-diabetic patients with rhegmatogenous retinal detachment with retinal tears secondary to posterior vitreous detachment or trauma. PlGF levels were quantified in vitreous and serum samples using an enzyme-linked immunosorbent assay (ELISA). Optical coherence tomography (OCT) scans from DR patients were evaluated to measure the central retinal thickness (CRT) and macular volume (MV). Results DR patients had significantly higher mean vitreous PlGF levels compared to non-DR patients (70.0±39.2 vs. 46.47±9.7 pg/mL, p-value=0.004). However, no significant increase in mean serum PlGF levels was observed in DR patients (p-value=0.232). Within the DR group, proliferative DR (PDR) patients presented significantly higher vitreous PlGF levels than non-PDR (NPDR) patients (76.5±41.0 vs. 42.5±5.0 pg/mL, p-value=0.009). There was no association between serum and vitreous PlGF levels. The correlation between vitreous PlGF levels and morphological parameters was rsp=0.175, p-value=0.488 for CRT, and rsp=0.288, p-value=0.262 for MV. Conclusion This study emphasizes the important role of PlGF in neovascularization, specifically highlighting its overexpression exclusively in vitreous from PDR patients. The observed increase in PlGF levels may be indicative of disease severity. The lack of correlation between vitreous and serum PlGF levels suggests a potential dissociation between intravitreal and systemic PlGF synthesis. Consequently, targeting PlGF in therapeutic approaches may offer an additional strategy for ocular pathologies with a neovascular component.

Comparison of diagnostic capability of macular ganglion cell complex vs retinal fiber layer thickness in primary open angle glaucoma patients of Indian origin.

Comparison of diagnostic capability of macular ganglion cell complex thickness vs. retinal nerve fiber layer (RNFL) thickness in patients of primary open-angle glaucoma (POAG). This cross-sectional observational study was carried out between June 2021 and October 2022 at a tertiary care hospital in North India. A total of 118 eyes were included in the study with 30 control and the rest 88 eyes with POAG were divided into three groups based on visual field loss Group 1 (30 eyes): early field loss with mean deviation (MD) < -6 dB; Group 2 (30 eyes): moderate field loss with MD -6 to -12 dB; and Group 3 (28 eyes): severe field loss with MD > -12 dB. Optical coherence tomography (OCT) scans to measure RNFL loss and ganglion cell inferior plexiform layer (GCIPL) loss were taken for each patient. Categorical variables were analyzed using either the Chi-square test or Fisher's exact test. A receiver operating characteristics analysis was calculated to determine optimal cut-off values of superior, inferior, and average GCIPL and RNFL for determining the severity of field loss as compared to controls (30 normal eyes). In the mild field loss group the sensitivity of superior, inferior, and average GCIPL was 86.7, 96.7, and 96.7%, respectively. Similarly, the specificity was 96.7, 93.3, and 100%, respectively. In the same group, the sensitivity of superior, inferior, and average RNFL was 70, 93, and 66%, respectively. Similarly, the specificity was 46.7, 83.3, and 70%, respectively. In the moderate and severe groups, the results were comparable. The sensitivity and specificity of GCIPL loss are significantly better than that of RNFL parameters in the mild field loss group.

Motion-artifact-free single shot two-beam optical coherence elastography system.

The assessment of the biomechanical properties of the skin using various imaging techniques has been used as a diagnostic tool in dermatology. Optical coherence elastography (OCE) is one of the techniques that allows for the measurement of elastic properties. OCE relies on measuring tissue displacements induced by external sources. Measuring the tissue's mechanical properties in vivo using OCE is often challenging due to bulk tissue movement. This study aimed to develop an OCE system that allows for minimizing the effects of bulk tissue movements. To achieve this, we designed a two-beam OCE system that simultaneously measures the tissue displacement at two locations on the sample. This allows for cancelling the effect of the tissue bulk movement, which is common to both measurement points. We used a piezoelectric transducer to generate surface acoustic waves (SAW) in the sample. The velocity of the excited waves, which is proportional to the rigidity of the sample, was measured by calculating the phase delay of the SAW at two locations on the sample. Simultaneous measurement at two locations was achieved by dividing a single light beam into two by focusing on the sample at two different locations. The two beams travel different optical path lengths, and the reflected signals were depth encoded in a single optical coherence tomography scan using a single reference beam. The system was characterized using different tissue-mimicking phantoms and the skin of healthy volunteers at the wrist and the palm. We achieved an approximately 50-fold increase in phase sensitivity measurement. We designed a simple two-beam OCE system that effectively minimizes the effect of tissue movement. We believe that the presented system will find immediate applications in the clinic to monitor the progression of systemic sclerosis disease.

Evaluation of the German Version of the Keratoconus Outcomes Research Questionnaire.

To translate, validate, and evaluate the psychometric properties of the German version of Keratoconus Outcomes Research Questionnaire (KORQ). This prospective study included 3 phases. In phase 1, the KORQ was translated in a standardized way; in phase 2, Rasch validation was performed; in phase 3, the validated questionnaire was evaluated in a separate patient cohort. All patients answered the German KORQ. Scheimpflug imaging (Pentacam) and optical coherence tomography scans (MS-39) were conducted. Corneal imaging measurements were correlated with patient-reported outcome measures. After standardized translation, 100 patients self-administered the German KORQ. Rasch analysis was conducted for psychometric testing of the KORQ. Based on the results of the Rasch analysis, the original German version of the KORQ was modified and any items showing a misfit were excluded. This resulted in a new shortened version of the KORQ, which was evaluated in 30 patients. The revised German KORQ met the criteria of Rasch analysis and showed excellent internal consistency reliability and convergent validity. The correlation between the KORQ score and various clinical measurements was examined using Spearman correlation. A significant moderate correlation was observed between the D (r = 0.237; P = 0.006) and Kmax (r = 0.162; P = 0.065) values of Pentacam. Inverse correlations were observed for thinnest pachymetry measured with MS-39 (r = -0.167; P = 0.058) and best corrected visual acuity (r = -0.210; P = 0.016). The shortened German KORQ met the assumptions of the Rasch model and displayed satisfactory psychometric properties. The German KORQ could be adopted as a powerful patient-reported outcome measures tool for German-speaking patients with keratoconus in the future.

A clear view of biofouling in spacer filled membrane filtration channels: Integrating OCT and CT for improved visualization and localization

Spiral wound membrane elements for reverse osmosis (RO) seawater desalination are increasingly important to produce clean water to cope with the rising global freshwater scarcity. Spiral wound elements are prone to biofouling development which can be monitored in-situ using optical coherence tomography (OCT). Although OCT has emerged as a dominant technology for nondestructive monitoring of membrane fouling, the application of OCT to study fouling on feed spacers has been limited because image processing of spacers is complex. In this study, an automated image processing algorithm was developed for visualization and quantification of fouling in spacer filled channels. The spacer shadow was used to estimate the location of the spacer in the OCT image. Subsequently, a computed tomography (CT) scan of the same spacer type was overlaid, providing a clear indicator of the spacer position. The spacer position was used to i) correct the distortion below the spacer, ii) visualize fouling in 3D with reference to the membrane and spacer, and iii) reproducibly and precisely locate images to make time series and compare parallel experiments. The results showed that the addition of a spacer geometry as a solid object in a 3D representation of an OCT-scan greatly improves visualization, because fouling and the spacer can be distinguished and the position of fouling relative to the spacer and membrane can be clearly seen. Moreover, the ability to select a dataset relative to the orientation of the spacer will enable objective and automated quantitative analysis in future work.

Deep Learning-Based Retinal Layer Segmentation in Optical Coherence Tomography Scans of Patients with Inherited Retinal Diseases.

In optical coherence tomography (OCT) scans of patients with inherited retinal diseases (IRDs), the measurement of the thickness of the outer nuclear layer (ONL) has been well established as a surrogate marker for photoreceptor preservation. Current automatic segmentation tools fail in OCT segmentation in IRDs, and manual segmentation is time-consuming. Patients with IRD and an available OCT scan were screened for the present study. Additionally, OCT scans of patients without retinal disease were included to provide training data for artificial intelligence (AI). We trained a U-net-based model on healthy patients and applied a domain adaption technique to the IRD patients' scans. We established an AI-based image segmentation algorithm that reliably segments the ONL in OCT scans of IRD patients. In a test dataset, the dice score of the algorithm was 98.7%. Furthermore, we generated thickness maps of the full retinal thickness and the ONL layer for each patient. Accurate segmentation of anatomical layers on OCT scans plays a crucial role for predictive models linking retinal structure to visual function. Our algorithm for segmentation of OCT images could provide the basis for further studies on IRDs.

Temporal-to-Nasal Macular Ganglion Cell and Inner Plexiform Layer Ratios in a Large Adult Twin Cohort:Correlations With Age and Heritability.

Temporal-to-nasal macular ganglion cell layer thickness ratios are reduced in albinism. We explored similar ratios in a large twin cohort to investigate ranges in healthy adults, correlations with age, and heritability. More than 1000 twin pairs from TwinsUK underwent macular optical coherence tomography (OCT) scans. Automated segmentation yielded thicknesses for the combined ganglion cell and inner plexiform layer (GCIPL) in Early Treatment of Diabetic Retinopathy Study subfields. Participants with diseases likely to affect these layers or segmentation accuracy were excluded. Inner and outer ratios were defined as the ratio of temporal-to-nasal GCIPL thickness for inner and outer subfields respectively. Corresponding ratios were obtained from a smaller cohort undergoing OCTs with a different device (three-dimensional (3D)-OCT, Topcon, Japan). Scans from 2300 twins (1150 pairs) were included (mean [SD] age, 53.9 (16.5) years). Mean (SD) inner and outer ratios were 0.89 (0.09) and 0.84 (0.11), correlating negatively with age (coefficients, -0.17 and -0.21, respectively). In males (150 pairs) ratios were higher and did not correlate significantly with age. Intrapair correlation coefficients were higher in monozygotic than dizygotic pairs; age-adjusted heritability estimates were 0.20 and 0.23 for inner and outer ratios, respectively. For the second cohort (n = 166), mean (SD) ratios were 0.93 (0.08) and 0.91 (0.09), significantly greater than for the larger cohort. Our study gives reference values for temporal-to-nasal macular GCIPL subfield ratios. Weak negative correlations with age emerged. Genetic factors may contribute to ∼20% to 23% of the variance in healthy individuals. The ratios differ according to the OCT platform used.

The features of dome-shape Macula and related complications in high myopia on optical coherence tomography.

This study used optical coherence tomography scanning and 3D reconstruction of the macular region in high myopia to examine more thoroughly and carefully the differences between high myopia-related macular complications with and without dome-shape macula (DSM) and to determine whether the DSM's fine structure has an effect on them. Retrospective analysis of the medical records of 345 eyes with high myopia who underwent an optical coherence tomography (OCT) examination. They were divided into the DSM group (69 eyes) and the group without DSM (276 eyes). Macular complications between the two groups were compared. The height of the DSM and the diameter of the dome base were measured. And then the association between DSM type, protrusion height and macular problems were analyzed. Epiretinal membrane (ERM) and extrafoveal schisis occurred more frequently in the DSM group, but the was no statistically significant difference in the frequency of foveal schisis between the two groups. The majority of eyes in the DSM categorization had a horizontal oval-shaped domain. In the DSM group, there was no evident difference in the percentage of eyes with macular complications in the groups below 150 um and above 150 um. OCT examination-based fine macular structure analysis reveals that DSM affects various macular problems in distinct ways. DSM could increase the risk of extrafoveal schisis and ERM while decreasing the risk of foveal schisis. The height of the DSM had no obvious impact on the prevalence of macular complications.

Diagnosis of posterior staphyloma using the radius of steepest curvature among retinal pigment epithelium segmentation line measured by optic coherent tomography

PurposeTo investigate a novel marker to diagnose posterior staphylomas by measuring the radius of the steepest curvature on the retinal pigment epithelium (RPE) segmentation line using optical coherence tomography (OCT).Study DesignRetrospective Cross-sectional Study.MethodsThe authors developed a prototype software to measure the radius of curvature on the RPE segmentation line of OCT. Twelve images of 9-mm radial OCT scans were used. The radius of curvature was measured at the steepest area of the RPE segmentation line, and the macular curvature (MC) index was calculated based on its reciprocal. Based on the wide-field fundus findings, the study sample was divided into three groups: definite posterior staphyloma, no posterior staphyloma, and undetermined. The differences of MC index among the groups and the correlation between the MC index, age, and axial length were analyzed.ResultsThe present study analyzed 268 eyes, with 54 (20.1%) with definite posterior staphyloma, 202 (75.4%) with no posterior staphyloma, and 12 (4.5%) with undetermined disease status. A maximum MC index of 37.5 was observed in the group with no posterior staphyloma, which was less than the minimum MC index of 42.7 observed in the group with definite posterior staphyloma. The MC index had strong correlations with the axial length and age in eyes with high myopia.ConclusionsEyes with posterior staphyloma have a steeper curvature than those with radius 8.44 mm, while eyes without posterior staphyloma do not. MC index 40 (radius 8.44 mm) might act as a reference to distinguish between those with and those without posterior staphyloma.

Comparative posterior corneal profile of keratoconus hydrops versus Haab's striae in congenital glaucoma.

Keratoconus eyes develop corneal decompensation more often compared to eyes with primary congenital glaucoma (PCG) following Descemet's membrane (DM) tear. This study was conducted to compare the posterior corneal morphology in areas with DM breaks with regards to DM and pre-Descemet's layer (PDL) between the two. In this cross-sectional comparative study, anterior segment optical coherence tomography (AS-OCT) scans of the posterior cornea of advanced keratoconus eyes with hydrops ( n = 12), PCG eyes with Haab's striae ( n = 15), and healthy control eyes ( n = 14) were compared for DM-PDL morphology. These were further corroborated by the histopathology of corneal buttons from keratoconus ( n = 14) and PCG ( n = 13) cases obtained following penetrating keratoplasty and compared with controls (enucleated retinoblastoma globes, n = 6) on light microscopy and collagen IV immunostaining. AS-OCT showed a thicker median DM/PDL complex in PCG (80 µm) versus keratoconus eyes (36 µm, P = 0.01; Kruskal-Wallis test). The median height and length of detached DM-PDL were significantly more in keratoconus versus PCG (145 μm, 1766.1 ± 1320.6 μm vs. 26.5 μm, 453.3 ± 303.2 μm, respectively, P = 0.012; Kruskal-Wallis test). Type-1 DM/PDL detachment (seen as a characteristic taut chord) in keratoconus (90%) was the most common morphological pattern versus intracameral twin protuberance (92%) following DM breaks in PCG. Histopathology confirmed thicker DM in PCG (median: 63.4 μm) versus keratoconus eyes (median: 33.2 µm) or controls (27.1 μm) ( P = 0.001; Kruskal-Wallis test). Greater height/length of DM/PDL detachment compounded by poor healing response (lower DM/PDL thickness) probably causes more frequent corneal decompensation in keratoconus eyes when compared to PCG eyes following DM tears.

Optical coherence tomography detection of retinal neural loss in patients with tuberous sclerosis

PurposeTuberous Sclerosis (TS) is a rare, multisystem genetic disease caused by mutations in the TSC1 and TSC2 genes, leading to abnormalities in cell differentiation and proliferation. This study aimed to evaluate the neural integrity of individuals with TS by using Optical Coherence Tomography (OCT) to examine the peripapillary retinal nerve fiber layer (RNFL) thickness and the macular thickness in patients with TS and to compare with healthy controls.MethodsPeripapillary and macular OCT scans (Optopol Revo NX SD OCT) were performed on 41 eyes from 22 TS patients, divided into two groups based on the presence of retinal hamartomas, and compared to 20 eyes from a control group. The average peripapillary RNFL thickness was measured for each quadrant. The macular total thickness and ganglion cell layer (GCL) + inner plexiform layer (IPL) thickness were measured based on the Early Treatment Diabetic Retinopathy Study (ETDRS) map. All measurements were then compared between the groups and controls.ResultsThe TS group showed significantly reduced RNFL thickness and macular thickness when compared to the control group. Specifically, patients with retinal hamartomas exhibited an even more pronounced thinning of both RNFL and macular thickness.ConclusionsThese findings suggest that TS patients undergo significant changes in retinal neurodevelopment and experience axonal loss. This finding may have significant prognostic utility regarding central nervous system degeneration in TS, particularly among patients with retinal hamartomas. OCT may serve as a valuable tool for assessing axonal structural abnormalities in TS patients.Trial Registration Number: Not applicable.

Quantitative assessments of retinal macular structure among rural-dwelling older adults in China: a population-based, cross-sectional, optical coherence tomography study

ObjectivesTo quantitatively assess and compare retinal macular structures of rural-dwelling older adults in China using two different optical coherence tomography (OCT) scanners and to examine their associations with demographic, lifestyle,...

Association of optic disc pallor and RNFL thickness with cerebral small vessel disease in the PREVENT-Dementia study.

We tested associations between two retinal measures (optic disc pallor, peripapillary retinal nerve fiber layer [pRNFL] thickness) and four magnetic resonance imaging markers of cerebral small vessel disease (SVD; lacunes, microbleeds, white matter hyperintensities, and enlarged perivascular spaces [ePVSs]). We used PallorMetrics to quantify optic disc pallor from fundus photographs, and pRNFL thickness from optical coherence tomography scans. Linear and logistic regression assessed relationships between retinal measures and SVD markers. Participants (N=108, mean age 51.6) were from the PREVENT Dementia study. Global optic disc pallor was linked to ePVSs in the basal ganglia in both left (β=0.12, standard error [SE]=0.05, P<0.05) and right eyes (β=0.13, SE=0.05, P<0.05). Associations were also noted in different disc sectors. No pRNFL associations with SVD markers were found. Optic disc pallor correlated with ePVSs in the basal ganglia, suggesting retinal examination may be a useful method to study brain health changes related to SVD. Optic disc pallor is linked to enlarged perivascular spaces in basal ganglia.There is no association between peripapillary retinal nerve fiber layer thickness and cerebral small vessel disease markers.Optic disc examination could provide insights into brain health.The sample included 108 midlife adults from the PREVENT Dementia study.

Compartmental Exudative Dynamics in Neovascular Age-Related Macular Degeneration: Volumetric Outcomes and Impact of Volatility in a Phase III Clinical Trial

PurposeTo examine retinal feature dynamics in eyes with neovascular age-related macular degeneration (nAMD) treated with anti-vascular endothelial growth factor (anti-VEGF) therapy and the relationship of these features with visual acuity. DesignPost hoc analysis of the phase 3, randomized, HAWK nAMD clinical trial. ParticipantsParticipants randomized to the brolucizumab 6 mg or aflibercept 2 mg arms of the trial. MethodsSpectral domain optical coherence tomography (OCT) scans collected at 4-week intervals were analyzed using an automated machine learning-enhanced segmentation and feature-extraction platform with manual verification. Quantitative volumetric measures of retinal and exudative features were exported at multiple timepoints over 48 weeks. Volatility of exudative features was calculated as the standard deviation of each feature value during the maintenance phase (week 12–48) of treatment. These features were examined for their associations with anatomic and functional outcomes. Main Outcome MeasuresLongitudinal intraretinal fluid (IRF) and subretinal fluid (SRF) volume, subretinal hyperreflective material (SHRM) volume, ellipsoid zone (EZ) integrity (EZ-retinal pigment epithelium [RPE] volume/thickness), and correlation with best corrected visual acuity (BCVA). ResultsIRF, SRF, and SHRM demonstrated significant volumetric reduction from baseline with anti-VEGF therapy (P<0.001 at each timepoint). EZ integrity measures demonstrated significant improvement from baseline (P<0.001 at each timepoint). Both EZ integrity and SHRM measures significantly correlated with BCVA at all timepoints (EZ-RPE volume: 0.38≤ r ≤0.47; EZ-RPE central subfield thickness: 0.22≤ r ≤0.41; SHRM volume: -0.33≤ r ≤-0.44). Following treatment initiation, correlations of IRF and SRF volume with BCVA were weak or nonsignificant. Eyes with lower volatility of IRF, SRF, and SHRM volumes during the maintenance phase showed greater improvements in EZ integrity (all P<0.01) and greater gains in BCVA (all P<0.01) at week 48 compared to eyes with higher volatility in those exudative parameters. ConclusionsQuantitative measures of SHRM volume and EZ integrity correlated more strongly with BCVA than retinal fluid volumes during treatment. High volatility of exudative parameters, including SRF, during the maintenance phase of treatment was associated with loss of EZ integrity and BCVA.

Changes in Neurodegeneration and Visual Prognosis in Branch Retinal Vein Occlusion after Resolution of Macular Edema

This study aimed to examine the thicknesses of the ganglion cell layer (GCL) and peripapillary retinal nerve fiber layer (RNFL) in eyes with resolved macular edema (ME) in branch retinal vein occlusion (BRVO) and determine their relationship with visual acuity (VA). This retrospective observational case–control study included 57 eyes of BRVO patients with resolved ME after treatment. The macular GCL thickness, peripapillary RNFL thickness, and central macular thickness (CMT) measured on swept-source optical coherence tomography scans with the contralateral eyes used as controls were evaluated. The mean CMT was 270.48 ± 32.7 μm; the mean RNFL thickness was 105.46 ± 25.94 μm in BRVO eyes. Although the average RNFL thickness was decreased in BRVO eyes compared to unaffected eyes, there was no significant difference between the groups. However, the temporal and nasal RNFL thicknesses were significantly different between the groups. The mean affected quadrant had a significantly thinner GCL compared to the corresponding opposite unaffected quadrant (p = 0.02). Final VA was significantly correlated with nasal and middle GCL thicknesses in the affected area (r = −0.512, p = 0.003 and r = −0.537, p = 0.001, respectively); no correlation was found between the average RNFL thickness and mean CMT. The peripapillary RNFL and GCL thicknesses of the affected area were reduced in BRVO eyes compared to unaffected eyes. VA significantly correlated with nasal and middle GCL thicknesses in the affected area. Inner retinal damage occurring in patients with ME secondary to BRVO may be related to the visual prognosis.

Genetic Characteristics and Clinical Manifestations of Foveal Hypoplasia in Familial Exudative Vitreoretinopathy

This study aimed to ascertain the occurrence of foveal hypoplasia (FH) in individuals diagnosed with familial exudative vitreoretinopathy (FEVR). Retrospective cohort study. In this study, FEVR families and sporadic cases were diagnosed at the Eye and ENT Hospital, Fudan University, between 2017 and 2023. All patients attended routine ophthalmologic examinations and genetic screenings. The classification of FH was determined using optical coherence tomography (OCT) scans. The FH condition was classified into 2 subgroups: group A (FH being limited to the inner layers) and group B (FH affecting the outer layers). A total of 102 eyes from 58 patients were suitable for analysis. Forty-nine mutations in LRP5, FZD4, NDP, TSPAN12, KIF11, CTNNB1, and ZNF408 were examined and detected, with 26 of them being novel. Forty-seven eyes (46.1%) revealed FH. The majority (53.2%) were due to the typical grade 1 FH. Patients with mutations in LRP5 and KIF11 were found to exhibit a higher prevalence of FH (P = .0088). Group B displayed the lowest visual acuity compared with group A (P = .048) and the group without FH (P < .001). The retinal arteriolar angle in group B was significantly smaller than in group A (P = .001) and those without FH (P < .001). This study offers a new diagnostic approach and expands the spectrum of FEVR mutations. LRP5 and KIF11 were found to be more susceptible to causing FH in patients with FEVR. FEVR eyes with FH exhibited both greater visual impairment and reduced retinal arteriolar angles. The assessment of foveal status in patients with FEVR should be valued.