CORRELATION OF OPTICAL INTENSITY ON OPTICAL COHERENCE TOMOGRAPHY AND VISUAL OUTCOME IN CENTRAL RETINAL ARTERY OCCLUSION

Correlation of visual acuity changes and optical coherence tomography imaging in patients with central retinal artery occlusion post-arterial thrombolysis

This retrospective study investigates the correlation between visual acuity changes and structural modifications observed through optical coherence tomography (OCT) in patients with central retinal artery occlusion (CRAO) treated with urokinase. Conducted at the Neuro-Ophthalmology Center of Xi'an People's Hospital from January 2022 to May 2023, the study included 217 CRAO patients (217 eyes), comprising 157 males and 60 females, aged 18 to 83 years (mean age: 57.8 ± 13.3 years). Key data were collected on visual acuity, ocular motility, and various imaging techniques at admission and post-thrombolysis. Results showed a significant improvement in visual acuity from 2.4 ± 0.5 to 1.9 ± 0.7 (P < 0.001) after treatment. Notably, patients with severe retinal damage had poorer visual recovery compared to those with milder damage. OCT analysis revealed a decrease in macular foveal retinal thickness from 415.5 ± 107.7 μm to 362.1 ± 93.8 μm (P < 0.001). Correlation analysis confirmed an association between visual acuity and retinal thickness (P < 0.001). Inter-observer variability for OCT grading was assessed using Cohen's Kappa, which yielded a Kappa value of 0.873 (P < 0.001). This study underscores the relationship between visual recovery and retinal structural changes in CRAO patients, emphasizing the efficacy of urokinase treatment, particularly in mild to moderate cases, and the need for personalized therapeutic strategies based on condition severity.

Retinal optical coherence tomography intensity spatial correlation features as new biomarkers for confirmed Alzheimer's disease

BACKGROUND

The nature and severity of Alzheimer's disease (AD) pathologies in the retina and brain correspond. However, retinal biomarkers need to be validated in clinical cohorts with confirmed AD biomarkers and optical coherence tomography (OCT). The main objective of this study was to investigate whether retinal metrics measured by OCT aid in the early screening and brain pathology monitoring for confirmed AD.

METHODS

This was a case-control study. All participants underwent retinal OCT imaging, and neurological examinations, including amyloid-β (Aβ) positron emission tomography. Participants were subdivided into cognitively normal (CN), mild cognitive impairment (MCI), and AD-derived dementia (ADD). Except retinal thickness, we developed the grey level co-occurrence matrix algorithm to extract retinal OCT intensity spatial correlation features (OCT-ISCF), including angular second matrix (ASM), correlation (COR), and homogeneity (HOM), one-way analysis of variance was used to compare the differences in retinal parameters among the groups, and to analyze the correlation with brain Aβ plaques and cognitive scores. The repeatability and robustness of OCT-ISCF were evaluated using experimental and simulation methods.

RESULTS

This study enrolled 82 participants, subdivided into 20 CN, 22 MCI, and 40 ADD. Compared with the CN, the thickness of retinal nerve fiber layer and myoid and ellipsoid zone were significantly thinner (P < 0.05), and ASM, COR, and HOM in several retinal sublayers changed significantly in the ADD (P < 0.05). Notably, the MCI showed significant differences in ASM and COR in the outer segment of photoreceptor compared with the CN (P < 0.05). The changing pattern of OCT-ISCF with interclass correlation coefficients above 0.8 differed from that caused by speckle noise, and was affected by OCT image quality index. Moreover, the retinal OCT-ISCF were more strongly correlated with brain Aβ plaque burden and MoCA scores than retinal thickness. The accuracy using retinal OCT-ISCF (AUC = 0.935, 0.830) was better than that using retinal thickness (AUC = 0.795, 0.705) in detecting ADD and MCI.

CONCLUSIONS

The study demonstrates that retinal OCT-ISCF enhance the association and detection efficacy of AD pathology compared to retinal thickness, suggesting retinal OCT-ISCF have the potential to be new biomarkers for AD.

Outcomes of Hyperbaric Oxygen Treatment for Central Retinal Artery Occlusion: A Single Center Experience

PURPOSE

To describe the outcomes of hyperbaric oxygen therapy (HBOT) for patients with central retinal artery occlusion (CRAO) at a single tertiary care center.

DESIGN

Retrospective clinical cohort study.

METHODS

Medical records of all patients diagnosed with CRAO who received HBOT at Mayo Clinic in Rochester, Minnesota from January 1, 2009 to December 31, 2020 were reviewed to confirm diagnosis, time from onset to presentation, exam findings, treatments, and follow-up data. Main outcome measures included final visual acuity (VA) and number of lines of improvement.

RESULTS

There were 41 patients diagnosed with CRAO who received HBOT during the 12-year study period. Median time from symptom onset to HBOT treatment was 9.5 h (interquartile range [IQR] 6.5, 14.0 h), and patients received a median of 4 HBOT sessions (IQR 2.5, 6.0 sessions). There were 20 patients who received HBOT within 9 h, 14 (70%) of which had clinically meaningful improvement in VA of ≥0.3 logMAR. In comparison, of the 21 patients treated after 9 h, 6 (28.6%) had VA improvement of ≥0.3 logMAR (P = .008). For all patients, the median logMAR VA at presentation was 2.00 (IQR 1.70, 2.30) and the median logMAR VA at follow-up was 1.94 (IQR 1.00, 2.00) (P < .001), with median lines of improvement of 3.0 (IQR 0.0, 7.0). For patients treated within 9 h, the median logMAR VA at presentation was 2.00 (IQR 1.93, 2.30) and the median logMAR VA at follow-up was 1.70 (IQR 0.54, 2.00). Patients treated within 9 h had statistically significant greater median lines of VA improvement than cases that were treated after >9 h from symptom onset at 5.9 (IQR 3.0, 10.0) and 0.0 (IQR 0.0, 3.0), respectively (P < .001). There was no difference in VA recovery associated with specific retinal exam findings such as cherry-red spot (P = .22) and cilioretinal artery perfusion (P = .36) compared to patients without those findings.

CONCLUSION

There was a statistically significant improvement in VA after HBOT treatment in CRAO patients among patients that received early HBOT, with patients receiving the most benefit when receiving treatment within 9 h. Randomized control trials in patients with CRAO are required to confirm the efficacy of HBOT.

A Remote Consult Retinal Artery Occlusion Diagnostic Protocol

PURPOSE

To report a novel protocol for diagnosis of retinal artery occlusions at the point of care using OCT and a remote consult model.

DESIGN

Retrospective case series and evaluation of a diagnostic test or technology.

PARTICIPANTS

Adult patients who presented with painless monocular vision loss and were diagnosed with a nonarteritic retinal artery occlusion.

METHODS

OCT machines were placed in the stroke center or emergency department at 3 hospitals within our health system. Patients who presented with painless monocular vision loss were evaluated by the stroke neurology service and an OCT was acquired. The images were interpreted remotely by the retina service. An in-house ophthalmology consult was not required to make the final treatment decision. Eligible patients were treated with intra-arterial tissue plasminogen activator (IA-tPA). Patients were followed by ophthalmology during their admission when an in-house consultation service was available or otherwise evaluated immediately after discharge.

MAIN OUTCOME MEASURES

Visual acuity (VA) before and after treatment with IA-tPA; time from last known well (LKW) to treatment; and time from presentation to treatment.

RESULTS

In the first 18 months since the protocol went live, 59 patients were evaluated. Twenty-five patients (42%) had a confirmed retinal artery occlusion based on OCT and follow-up examination. Ten patients were eligible for treatment, and 9 patients received treatment with IA-tPA. There was a statistically significant improvement in mean VA from logarithm of the minimum angle of resolution (logMAR) 2.14 to logMAR 0.7 within 24 hours after treatment (P = 0.0001) and logMAR 1.04 after 4 weeks (P = 0.01). Clinically significant improvement was noted in 66% of patients within 24 hours and maintained through 1 month in 56% of all treated patients. The mean time to treatment from LKW was 543 minutes and from presentation at the stroke center was 146 minutes.

CONCLUSIONS

We report the successful implementation of a remote consult protocol using point-of-care automated OCT. This novel paradigm demonstrates the potential utility of remote consult services for the diagnosis of time-sensitive ophthalmic emergencies.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Prevalence and Distribution of Macular Fluid with Central Retinal Artery Occlusion and Anterior Ischemic Optic Neuropathy

Purpose

To examine the prevalence and distribution of fluid within a cohort of eyes with acute central retinal artery occlusion (CRAO) and non-arteritic anterior ischemic optic neuropathy (AION) using optical coherence tomography (OCT).

Methods

A retrospective analysis of patient records and OCT imaging. Patients presenting with acute CRAO or AION who had available macular OCT imaging and no co-morbidities known to cause macular fluid were included in the analysis. Baseline characteristics, visual acuity (VA), and fluid presence and distribution among the retinal layers were recorded.

Results

In the 16 eyes with acute CRAO, fluid was noted in 5 eyes (31%), which was mainly subretinal (3 eyes) or intraretinal located within the outer retinal layers (3 eyes). Only one eye had inner retinal cysts. Of the 11 eyes with acute AION, fluid was present in 8 eyes (73%). Subretinal fluid was noted in 4 eyes and extended to the foveal area in 3 of them, and outer retinal versus inner retinal cysts were noted in 6 versus 3 eyes, respectively. None of the eyes showed hard exudate deposition. In the small subset of eyes with CRAO and macular fluid that were followed-up, VA improved, while in eyes with AION, VA remained stable.

Conclusion

Macular fluid on OCT is not an uncommon feature of acute CRAO and AION and is mainly distributed within the outer retinal layers or subretinal space. Fluid is an understudied feature of retinal and optic nerve head infarction and may have a role in predicting neuronal damage extent and visual outcome.

Alterations of outer retinal reflectivity in diabetic patients without clinically detectable retinopathy

PURPOSE

This study aimed to investigate alterations of outer retinal reflectivity on spectral-domain optical coherence tomography (OCT) in diabetic patients without clinically detectable retinopathy (NDR).

METHODS

In this retrospective study, 64 NDR patients and 71 controls were included. Relative reflectivity (RR) of the ellipsoid zone (EZ), photoreceptor outer segment (OS) and inner segment (IS), and outer nuclear layer (ONL) at the foveola and at 500 μm, 1000 μm, and 2000 μm nasal (N), temporal (T), superior (S), and inferior (I) to the foveola was measured by cross-line OCT and ImageJ. Retinal vessel densities (VD) in fovea, parafovea, and perifovea areas were detected by OCT angiography (OCTA).

RESULTS

EZ RR in most retinal locations was significantly lower in NDR eyes compared to controls (all P < 0.05), except the foveola. Compared with controls, NDR eyes also displayed lower RR at N2000, T2000, S1000, and I1000 of OS, at S500 and I500 of IS, and at I500 of ONL (all P < 0.05). Negative correlations could be observed between retinal RR and diabetes duration, HbA1c, and best-corrected visual acuity (BCVA) (r =  - 0.303 to - 0.452). Compared to controls, EZ, OS, and IS RR of the NDR eyes showed lower correlation coefficients with whole image SCP and DCP VD of parafovea and perifovea regions.

CONCLUSION

Outer retinal reflectivity, along with the coefficients between retinal reflectivity and VD, is reduced in NDR patients and is correlated with diabetes duration, HbA1c, and BCVA. The reduction of outer retinal reflectivity may be a potential biomarker of early retinal alterations in diabetic patients.

Evaluation of optic coherence tomography findings in patients with inflammatory bowel disease

BACKGROUND

Ocular complications are known to appear in inflammatory bowel disease (IBD). Among these, posterior segment complications can lead to substantial morbidity. The aim of the study is to evaluate the retinal nerve fiber layer (RNFL), ganglion cell-inner plexiform layer (GCIPL), and macula thickness measurement in patients with IBD.

METHODS

A total of 118 patients with IBD (42 Crohn's disease (CD), 76 ulcerative colitis (UC)) and 52 healthy subjects were included in the study. RNFL, GCIPL, and macula thickness were measured using spectral-domain optical coherence tomography (SD-OCT).

RESULTS

The central macular thickness was increased, mean and all superior quadrants of GCIPL thickness measurements were significantly decreased, but RNFL thickness wasn't changed in CD compared to healthy subjects. Although the central macular thickness increased, no change was observed in mean RNFL and GCIPL in UC compared to healthy subjects. Mean RNFL, GCIPL, and macular thickness did not differ during the remission and active phases of the disease in IBD. There was no difference in RNFL, GCIPL, and macular thicknesses in CD patients in terms of the location and behavior of the disease. A significant thickness increase was found in extensive type UC for inferior RNFL value compared to the left side and proctitis.

CONCLUSIONS

IBD may cause an increase in macular thickness. This finding may be related to the inflammation or ischemia of the retina. The use of SD-OCT in ophthalmologic examination in patients with IBD may enable early detection of retinal changes and alert the clinician to complications of IBD.

Graph Attention U-Net for Retinal Layer Surface Detection and Choroid Neovascularization Segmentation in OCT Images

Choroidal neovascularization (CNV) is a typical symptom of age-related macular degeneration (AMD) and is one of the leading causes for blindness. Accurate segmentation of CNV and detection of retinal layers are critical for eye disease diagnosis and monitoring. In this paper, we propose a novel graph attention U-Net (GA-UNet) for retinal layer surface detection and CNV segmentation in optical coherence tomography (OCT) images. Due to retinal layer deformation caused by CNV, it is challenging for existing models to segment CNV and detect retinal layer surfaces with the correct topological order. We propose two novel modules to address the challenge. The first module is a graph attention encoder (GAE) in a U-Net model that automatically integrates topological and pathological knowledge of retinal layers into the U-Net structure to achieve effective feature embedding. The second module is a graph decorrelation module (GDM) that takes reconstructed features by the decoder of the U-Net as inputs, it then decorrelates and removes information unrelated to retinal layer for improved retinal layer surface detection. In addition, we propose a new loss function to maintain the correct topological order of retinal layers and the continuity of their boundaries. The proposed model learns graph attention maps automatically during training and performs retinal layer surface detection and CNV segmentation simultaneously with the attention maps during inference. We evaluated the proposed model on our private AMD dataset and another public dataset. Experiment results show that the proposed model outperformed the competing methods for retinal layer surface detection and CNV segmentation and achieved new state of the arts on the datasets.

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

PURPOSE

To investigate the diagnostic value of optical density ratio (ODR) in various diseases with subretinal fluid (SRF) due to different pathophysiologies.

METHODS

Patients 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.

RESULTS

Optical 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).

CONCLUSION

ODR 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.

Changes in macrophage-like cells characterized by en face optical coherence tomography after retinal stroke

Purpose

The retina could serve as a window of neuroinflammation, but the in vivo changes in macrophage-like cell (MLC), such as microglia, in acute ischemic retinal stroke remain unclear. Thus, the current study aimed to investigate the in vivo changes in MLC characterized by en face optical coherence tomography (OCT) after acute ischemic retinal stroke.

Methods

Twenty patients with unilateral acute nonarteritic reperfused central retinal artery occlusion (CRAO) were participated in this study, and their contralateral eyes served as control group. A 3 μm en face OCT slab on the inner limiting membrane of the optic nerve head (ONH) region or macular region was used to visualize and binarize the MLCs. The MLCs were binarized and quantified using a semiautomated method. OCT angiography was used to evaluate the reperfusion status and obtain the structural data of the inner retina in the ONH and macula. The thickness of the ganglion cell complex in the macular region was measured. The optical intensity and optical intensity ratio of the inner retina were calculated to evaluate the ischemia severity.

Results

In the ONH region, decreased vessel densities of radial peripapillary capillaries accompanied by increased thickness of the retinal nerve fiber layer were found in the CRAO eyes in comparison to the unaffected eyes (p=0.001, p=0.009, respectively). In the macular region, significantly lower vessel densities in both the superficial and deep capillary plexus and increased thickness of the ganglion cell complex were also found in the CRAO eyes (all p ≤ 0.001). The ONH and macular MLC quantities and densities in CRAO eyes were significantly higher than those in the unaffected eyes (both p<0.001). Larger and plumper MLCs were observed in the CRAO eyes compared with their unaffected eyes. ONH and macular MLC densities were positively associated with the disease duration in the acute phase and the optical intensity ratio of inner retina.

Conclusions

The increased density and morphological changes of MLCs may indicate the aggregation and activation of MLCs following acute reperfused CRAO. The aggregation of MLCs may be more pronounced in CRAO eyes with longer disease duration and more severe ischemia. MLCs characterized by en face OCT may serve as an in vivo visual tool to investigate neuroinflammation in the ischemic-reperfusion process of stroke.

[Optical coherence tomography in the differential diagnostics of important neuro-ophthalmological disease patterns]

There are many disease patterns that are treated jointly by neurologists and ophthalmologists, for which optical coherence tomography (OCT) is of important differential diagnostic significance. In this context neurologists are mainly confronted by two patient collectives: patients with an acute ischemic event, who present with an acute but painless monocular visual deterioration (for central retinal artery occlusion) or with a monocular visual field defect (for arterial branch occlusion or anterior ischemic optic neuropathy). The second collective is patients without ophthalmological symptoms but with conspicuous optic nerve findings (papilledema or optic disc drusen). In this overview article both patient collectives are considered separately. In addition, the most important OCT findings for optic neuritis are presented. Before the disease patterns are described in detail, the normal OCT findings and the diagnostic possibilities of OCT are explained.

Inner Retinal Layer Hyperreflectivity Is an Early Biomarker for Acute Central Retinal Artery Occlusion

Purpose

To investigate inner retinal hyperreflectivity on optical coherence tomography (OCT) as a potential biomarker indicating acute central retinal artery occlusion (CRAO).

Methods

A total of 56 patients at two university hospitals with acute CRAO (symptom onset ≤48 h) were included in this retrospective study. The optical intensity of the inner retinal layers was determined in both eyes and the relationship between symptom onset and inner retinal layer optical intensity in OCT scans compared to the unaffected fellow eye was analyzed. Several differential diagnoses [central retinal vein occlusion, anterior ischemic optic neuropathy, diabetic macular edema, and subretinal fibrosis/disciform scar (Junius-Kuhnt)] served as controls to validate optical intensity-based diagnosis of CRAO.

Results

CRAO strongly correlated with an increased inner retinal layer hyperreflectivity in this cohort with acute CRAO with a time since symptom onset ranging from 1.1 to 48.0 h. Receiver operating characteristic (ROC) analysis showed an area under the curve of 0.99 to confirm CRAO with a true positive rate of 0.93 and a false positive rate of 0.02. No correlation between optical intensity and time since symptom onset was noticeable. None of the differential diagnoses did show an elevated optical intensity of the inner retinal layers as it was detectable in CRAO.

Conclusion

OCT-based determination of inner retinal layer hyperreflectivity is a very promising biomarker for a prompt diagnosis of CRAO in an emergency setting. This may be of major interest to speed up the administration of a possible thrombolytic treatment.

Intravenous lipo-prostaglandin E1 administration for patients with acute central retinal artery occlusion

Objective

This study aimed to investigate the anatomical and functional changes in patients with central retinal artery occlusion (CRAO) (n=21) treated with 10 µg/day intravenous liposomal prostaglandin E1 (lipo-PGE1).

Methods and analysis

We used best-corrected visual acuity (BCVA), central retinal thickness with spectral domain optical coherence photography, optical intensity ratio (OIR) with imageJ software and retinal vessel diameter with fundus photography as indicators. Data were analysed using Tukey’s multiple comparisons, Wilcoxon test or Spearman’s correlation analysis as appropriate.

Results

BCVA was significantly improved at 1 month and 3 months after the initial visit (from 2.18±0.60 to 1.54±0.84 and 1.53±0.88, p=0.030 and p=0.027, respectively). The ratio of retinal vein diameter to optic disc diameter increased in the first month (from 0.40%±0.13% to 0.52%±0.16%, p=0.005). In addition, the OIR at the initial visit was significantly correlated with BCVA at 3 months (p=0.006, r=0.58). No severe adverse effects were observed.

Conclusion

The results showed that visual acuity and retinal vein constriction improved after lipo-PGE1 therapy. In addition, the OIR in the initial phase can be an indicator of visual prognosis after treatment with PGE1 in patients with CRAO.

[Optical coherence tomography in the differential diagnostics of important neuro-ophthalmological disease patterns]

There are many disease patterns that are treated jointly by neurologists and ophthalmologists, for which optical coherence tomography (OCT) is of important differential diagnostic significance. In this context neurologists are mainly confronted by two patient collectives: patients with an acute ischemic event, who present with an acute but painless monocular visual deterioration (for central retinal artery occlusion) or with a monocular visual field defect (for arterial branch occlusion or anterior ischemic optic neuropathy). The second collective is patients without ophthalmological symptoms but with conspicuous optic nerve findings (papilledema or optic disc drusen). In this overview article both patient collectives are considered separately. In addition, the most important OCT findings for optic neuritis are presented. Before the disease patterns are described in detail, the normal OCT findings and the diagnostic possibilities of OCT are explained.

Semi-Automated Quantification of Retinal and Choroidal Biomarkers in Retinal Vascular Diseases: Agreement of Spectral-Domain Optical Coherence Tomography with and without Enhanced Depth Imaging Mode

BACKGROUND

We compared with and without enhanced depth imaging mode (EDI) in semi-automated quantification of retinal and choroidal biomarkers in optical coherence tomography (OCT) in patients with diabetic retinopathy (DR) or retinal vein occlusion (RVO) complicated by macular edema. We chose to study three OCT biomarkers: the numbers of hyperreflective foci (HF), the ellipsoid zone reflectivity ratio (EZR) and the choroidal vascularity index (CVI), all known to be correlated with visual acuity changes or treatment outcomes.

METHODS

In a single examination, one eye of each patient (n = 60; diabetic retinopathy: n = 27, retinal vein occlusion: n = 33) underwent macular 870 nm spectral domain-OCT (SD-OCT) B-scans without and with EDI mode. Semi-automated quantification of HF, EZR and CVI was applied according to preexisting published protocols. Paired Student's t-test or Wilcoxon rank-sum test was used to test for differences in subgroups. Intraclass correlation coefficient (ICC) and Bland-Altman plots were applied to describe the agreement between quantification in EDI and conventional OCT mode. The effect of macular edema on semi-automated quantification was evaluated.

RESULTS

For the entire cohort, quantification of all three biomarkers was not significantly different in SD-OCT scans with and without EDI mode (p > 0.05). ICC was 0.78, 0.90 and 0.80 for HF, EZR and CVI. The presence of macular edema led to significant differences in the quantification of hyperreflective foci (without EDI: 80.00 ± 33.70, with EDI: 92.08 ± 38.11; mean difference: 12.09, p = 0.03), but not in the quantification of EZR and CVI (p > 0.05).

CONCLUSION

Quantification of EZR and CVI was comparable whether or not EDI mode was used. In conclusion, both retinal and choroidal biomarkers can be quantified from one single 870 nm SD-OCT EDI image.

DW-Net: Dynamic Multi-Hierarchical Weighting Segmentation Network for Joint Segmentation of Retina Layers With Choroid Neovascularization

Choroid neovascularization (CNV) is one of the blinding factors. The early detection and quantitative measurement of CNV are crucial for the establishment of subsequent treatment. Recently, many deep learning-based methods have been proposed for CNV segmentation. However, CNV is difficult to be segmented due to the complex structure of the surrounding retina. In this paper, we propose a novel dynamic multi-hierarchical weighting segmentation network (DW-Net) for the simultaneous segmentation of retinal layers and CNV. Specifically, the proposed network is composed of a residual aggregation encoder path for the selection of informative feature, a multi-hierarchical weighting connection for the fusion of detailed information and abstract information, and a dynamic decoder path. Comprehensive experimental results show that our proposed DW-Net achieves better performance than other state-of-the-art methods.

Detectability of Retinal Diffusion Restriction in Central Retinal Artery Occlusion is Linked to Inner Retinal Layer Thickness

PURPOSE

To investigate retinal microstructure differences in central retinal artery occlusion (CRAO) patients with and without visible retinal diffusion restriction (RDR) on diffusion-weighted magnetic resonance imaging (DWI).

METHODS

Consecutive CRAO patients with available optical coherence tomography (OCT) and DWI, both performed within 7 days after symptom onset, were included in a retrospective cohort study. The OCT scans were reviewed to assess retinal layer thickness, optical intensity and structural integrity. The OCT findings were compared between patients with and without visible RDR on DWI using Mann-Whitney U or Pearson's Χ² test.

RESULTS

A total of 56 patients (mean age 70.8 ± 12.8 years) were included. RDR was observed in 38 subjects (67.9%) with visually correlating low ADC map in 26 of 38 cases (68.4%). Superior and inferior parafoveal macular thickness measurements (SMT, IMT) of RDR negative patients were significantly lower when compared to RDR+ patients (370.5 ± 43.8 µm vs. 418.2 ± 76.0 µm, p = 0.016; 374.4 ± 42.9 µm vs. 428.8 ± 63.2 µm, p = 0.004) due to differences in inner retinal layer thickness (IRLT, 188.8 ± 34.4 µm vs. 234.7 ± 49.0 µm, p = 0.002). IRLT values of RDR negative patients were higher in 1.5T compared to 3T the DWI (205.0 ± 26.0 µm vs. 168.6 ± 32.8 µm, p = 0.026).

CONCLUSIONS

Detectability of RDR is likely contingent upon the degree of ischemic retinal swelling in CRAO. Technical adjustments to the DWI protocol, such as increased field strength, may improve visibility of RDR.

[Acute diagnostics of central retinal artery occlusion and biomarkers of ischemia : Diagnostics with consequences?]

BACKGROUND

Acute central retinal artery occlusion (CRAO) represents an ophthalmological emergency with neurological implications, which must be immediately investigated and treated. Intravenous thrombolysis could improve the prognosis only within the first 4.5 h due to limited retinal tolerance to ischemia. Accordingly, ophthalmological acute diagnostics should be reduced to the minimum necessary followed by immediate referral to a clinic with neurovascular expertise. The typical anamnesis is well-suited for triaging and should be carried out ín a standardized way in order to determine the onset of symptoms as exactly as possible. In addition to pathognomic findings in fundoscopy, there are characteristic ischemia-related changes in optical coherence tomography (OCT), which document ischemia in the inner retina and under some circumstances can provide inferences for the onset of ischemia.

OBJECTIVE

This review article summarizes the acute ophthalmological diagnostic management of acute CRAO with a focus on the typical OCT and transorbital ultrasound (TOUS) findings and discusses their potential use as ischemic biomarkers.

CONCLUSION

Characteristic biomarkers make OCT an important diagnostic tool in the management of acute CRAO. Additional information can be obtained by TOUS. With an evidence-based treatment established in the future both tools could be used for indications for treatment and for estimating the prognosis.

[Update on intravenous lysis treatment : The REVISION trial]

BACKGROUND

To date, no evidence-based treatment for acute non-arteritic central retinal artery occlusion (CRAO) exists. Considering the limited ischemia tolerance of the retina and the results of multiple case series, increasing expectations are directed towards an early intravenous thrombolysis within 4.5 h after CRAO onset.

OBJECTIVE

The current literature regards timely retinal reperfusion as the only potentially beneficial therapeutic option to treat non-arteritic CRAO. Available data on the efficacy and safety of thrombolysis in CRAO are presented and discussed. On the basis of these data, the prospective, randomized, double-blind, placebo-controlled REVISION trial (early REperfusion therapy with intravenous alteplase for recovery of VISION in acute central retinal artery occlusion) will shortly be initiated in 25 centers across Germany in order to investigate early intravenous thrombolysis in acute CRAO. The main inclusion criteria of the REVISION trial are outlined, which may help ophthalmologists to identify study candidates and facilitate rapid referral to a study center.

CONCLUSION

The efficacy of intravenous thrombolysis in acute ischemic stroke is critically time dependent. This may also be assumed in acute CRAO; however, definite evidence still needs to be provided. Until then, the motto "time is retina" should be applied and intravenous thrombolysis should be offered to CRAO patients as part of randomized trials (such as REVISION). According to the current literature, other acute treatment approaches (such as paracentesis) are not indicated.

Structural and Functional Imaging of the Retina in Central Retinal Artery Occlusion - Current Approaches and Future Directions

Central retinal artery occlusion (CRAO) is a form of acute ischemic stroke which affects the retina. Intravenous thrombolysis is emerging as a compelling therapeutic approach. However, it is not known which patients may benefit from this therapy because there are no imaging modalities that adequately distinguish viable retina from irreversibly infarcted retina. The inner retina receives arterial supply from the central retinal artery and there is robust collateralization between this circulation and the outer retinal circulation, provided by the posterior ciliary circulation. Fundus photography can show canonical changes associated with CRAO including a cherry-red spot, arteriolar boxcarring and retinal pallor. Fluorescein angiography provides 2-dimensional imaging of the retinal circulation and can distinguish a complete from a partial CRAO as well as central versus peripheral retinal non-perfusion. Transorbital ultrasonography may assay flow through the central retinal artery and is useful in the exclusion of other orbital pathology that can mimic CRAO. Optical coherence tomography provides structural information on the different layers of the retina and exploratory work has described its utility in determining the time since onset of ischemia. Two experimental techniques are discussed. 1) Retinal functional imaging permits generation of capillary perfusion maps and can assay retinal oxygenation and blood flow velocity. 2) Photoacoustic imaging combines the principles of optical excitation and ultrasonic detection and - in animal studies - has been used to determine the retinal oxygen metabolic rate. Future techniques to determine retinal viability in clinical practice will require rapid, easily used, and reproducible methods that can be deployed in the emergency setting.

Capturing the Occult Central Retinal Artery Occlusion Using Optical Coherence Tomography

Aims: To report spectral-domain optical coherence tomography (OCT) findings in cases of impending or occult central retinal artery occlusion (CRAO) in which a diagnosis other than CRAO was made on initial presentation.Methods: Retrospective, observational case series of patients diagnosed with CRAO for whom on initial presentation fundal examination and OCT findings were deemed unremarkable and/or a diagnosis other than CRAO was made. OCT images from the initial presentation were then reviewed for evidence of inner retinal ischaemia.Results: In total, 214 cases of CRAO were identified. Eleven patients (5.14%) had been given an alternative initial diagnosis at their first presentation in casualty and were included. The age range was 20-84 years and 81% (9/11) were male. On review of initial OCT imaging performed in casualty, all cases had evidence of inner retinal ischaemia.Conclusions: CRAO is an ophthalmic emergency which leads to vision loss which is often irreversible. Examination of the fundus may be normal early in the course of the disease and therefore a timely diagnosis may be missed. This case series reports the OCT findings of inner retinal ischaemia in patients with occult or impending CRAO which may aid in the early diagnosis and referral to stroke services.

Optical coherence tomography-based determination of ischaemia onset - the temporal dynamics of retinal thickness increase in acute central retinal artery occlusion

PURPOSE

Acute central retinal artery occlusion (CRAO) induces ischaemic retinal oedema. The purpose of this study was to define sensitivity and specificity of optical coherence tomography (OCT) based retinal thickness analysis in determining ischaemia onset in CRAO.

METHODS

The relative retinal thickness increase (RRTI) in comparison with the fellow eye was analysed retrospectively in OCT scans of 66 patients diagnosed with CRAO between January 2010 and December 2019 within 48 hr of ischaemia onset. The natural course of RRTI and the sensitivity and specificity of OCT-based determination of ischaemia onset in identifying CRAO within 4.5 hr using the RRTI were evaluated.

RESULTS

Relative retinal thickness increase (RRTI) in acute CRAO follows a hyperbolic curve with a steep incline within the early phase after which it reaches a plateau. Optical coherence tomography (OCT)-based retinal thickness analysis in CRAO allows to differentiate patients with ischaemia onset within the past 4.5 hr or thereafter with a sensitivity of 100% and a specificity of 94.3%.

CONCLUSION

Relative retinal thickness increase (RRTI) allows to identify CRAO patients that are eligible for a potentially beneficial reperfusion therapy within a therapeutic window of 4.5 hr with a high accuracy. Especially in patients with unknown ischaemia onset, this diagnostic tool could be of major importance in the future clinical management.

Differences in the multicolour imaging features between the superficial and deep vascular occlusions

Purpose To describe the multicolour imaging (MI) findings in superficial and deep vascular plexus occlusions.

METHODS

In this retrospective observational study, patients diagnosed with central retinal artery and branch retinal artery occlusion, cotton-wool spot, paracentral acute middle maculopathy and acute macular neuroretinopathy between January 2018 and June 2019 were included. Colour fundus photograph, optical coherence tomography and MI of these patients were analysed.

RESULTS

A total of 41 eyes of 40 patients were included in this study. In eyes with central retinal artery occlusion, MI showed white areas in the retina with orange foveal centre. In eyes with branch retinal artery occlusion, MI showed white area along the affected retinal quadrant without an orange foveal centre. In pure superficial vascular plexus occlusions as in cotton-wool spots, the lesion was identified on MI as a white lesion. On MI, paracentral acute middle maculopathy showed parafoveal white areas with orange foveal centre while acute macular neuroretinopathy on MI parafoveal greyish-white areas with normal foveal centre.

CONCLUSION

En-face images using MI technology can provide yet another way to identify the level of retinal vasculature involvement which complements the existing gold standard of optical coherence tomography imaging.

Retinal oedema in central retinal artery occlusion develops as a function of time

PURPOSE

Time is the key criterion in the management of non-arteritic central retinal artery occlusion (NA-CRAO). However, the precise onset of vision loss is often difficult to determine. This study aimed to evaluate the temporal changes of retinal thickness in acute NA-CRAO and the potential of this parameter to be used as a surrogate marker to estimate the onset of retinal ischaemia.

METHODS

Optical coherence tomography was used to continuously assess retinal thickness and oedema progression rate in six porcine eyes. Additionally, a retrospective analysis of 12 patients with acute NA-CRAO was performed to determine association strength and progression rate between retinal thickness and onset of ischaemia. All Optical coherence tomography (OCT) scans (pigs and NA-CRAO patients) were performed within an ischaemic time frame of up to 9 hr.

RESULTS

Retinal oedema progression rate in pigs was 25.32 µm/hr [CI 95%: 24.24-26.40 µm/hr]. Retrospective analysis of the patients revealed a strong correlation between retinal oedema and duration of ischaemia (Spearman's rho = 0.77, p = 0.004) with an estimated progression rate of 10.02 µm/hr [CI 95%: 3.30-16.74 µm/hr].

CONCLUSION

Retinal thickness increases with oedema formation, and ischaemia onset is strongly correlated with this structural biomarker in both, pigs and NA-CRAO patients. Prospective clinical trials will have to determine the clinical feasibility of retinal thickness measurements as a biomarker to support clinical management of NA-CRAO.

Hyperreflectivity of Inner Retinal Layers as a Quantitative Parameter of Ischemic Damage in Acute Retinal Vein Occlusion (RVO): An Optical Coherence Tomography Study

Purpose

To investigate the reflectivity changes of inner retinal layers in acute retinal vein occlusion (RVO) on spectral-domain optical coherence tomography (SD-OCT) and to correlate these values with other known parameters of acute ischemic damage.

Patients and Methods

In this retrospective and observational case series, 230 eyes from 115 patients with acute RVO (central or branch) were categorized as ischemic or non-ischemic depending on fluorescein angiography (FA) images at baseline. Thickness and reflectivity of selected retinal layers were measured from SD-OCT images at baseline. Reflectivity values were correlated with other parameters of acute ischemic damage (best-corrected visual acuity (BCVA), retinal thickness, extent of macular edema, ischemic area on fluorescein angiography). The data were compared with contralateral eyes (controls). Prominent middle limiting membrane sign (p-MLM) was also registered.

Results

RVO reflectivity values differed significantly in all retinal layers compared to controls (P<0.001). Ischemic RVO eyes had higher optical intensity values for the innermost retinal layer (IMRL; P=0.008) and inner retinal layer (P=0.019) compared to non-ischemic cases. For all RVO eyes as well as central RVO, severity parameters like BCVA, central and total retinal thickness showed a strong correlation with the IMRL reflectivity. In branch RVO, BCVA remained significantly correlated with the IMRL reflectivity, while the thickness values showed significant correlation only for central foveal thickness in non-ischemic branch RVO type. The p-MLM was seen on OCT in 94% of the ischemic and in 66% of the non-ischemic RVO cases.

Conclusion

Acute RVO leads to increased reflectivity of inner retinal layers with significantly higher values in the ischemic vs non-ischemic type. Increased inner retinal layers’ reflectivity correlated significantly with BCVA, retinal thickness of separate retinal layers, as well as ischemic area on FA. Quantitative non-invasive measurement of inner retinal layers’ reflectivity might be used to determine the extent of acute ischemic retinal damage in RVO.

Adaptive-Guided-Coupling-Probability Level Set for Retinal Layer Segmentation

Quantitative assessment of retinal layer thickness in spectral domain-optical coherence tomography (SD-OCT) images is vital for clinicians to determine the degree of ophthalmic lesions. However, due to the complex retinal tissues, high-level speckle noises and low intensity constraint, how to accurately recognize the retinal layer structure still remains a challenge. To overcome this problem, this paper proposes an adaptive-guided-coupling-probability level set method for retinal layer segmentation in SD-OCT images. Specifically, based on Bayes's theorem, each voxel probability representation is composed of two probability terms in our method. The first term is constructed as neighborhood Gaussian fitting distribution to characterize intensity information for each intra-retinal layer. The second one is boundary probability map generated by combining anatomical priors and adaptive thickness information to ensure surfaces evolve within a proper range. Then, the voxel probability representation is introduced into the proposed segmentation framework based on coupling probability level set to detect layer boundaries. A total of 1792 retinal B-scan images from 4 SD-OCT cubes in healthy eyes, 5 cubes in abnormal eyes with central serous chorioretinaopathy and 5 SD-OCT cubes in abnormal eyes with age-related macular disease are used to evaluate the proposed method. The experiment demonstrates that the segmentation results obtained by the proposed method have a good consistency with ground truth, and the proposed method outperforms six methods in the layer segmentation of uneven retinal SD-OCT images.

Evaluation of the Initial Optical Coherence Tomography Parameters in Anticipating the Final Visual Outcome of Central Retinal Vein Occlusion

Purpose

To evaluate the predictive and associated factors in determining the visual outcome in patients having central retinal vein occlusion (CRVO)-related macular edema (ME).

Methods

The charts of the patients who were treated due to CRVO-related visual disturbance were reviewed. The optical coherence tomography (OCT) images of eyes were analyzed, and disorganization of retinal inner layers (DRILs), ellipsoid zone (EZ) and external limiting membrane (ELM) disruption length, hyper-reflectivity of retinal inner layer (HRIL) existence, baseline and final visual acuity (VA), subfoveal thickness (SFT), subretinal fluid (SRF), and injection numbers were noted. The regression and correlation analyses were applied.

Results

Thirty eyes of thirty patients were included in the study. The mean follow-up time was 17.5 ± 11 (8-47) months. The mean baseline VA was 1.4 ± 0.7 (0.2-3.1) logMAR. A total of 87 intravitreal injections were applied for the treatment of ME during the follow-up. The initial mean central subfield thickness was 795 ± 264 (1470-398) μm. HRIL and SRF were observed in 16 and 23 eyes at the initial visit, respectively. The final mean VA was 1.2 ± 0.9 (0.1-3.1) logMAR. At the final visit, additional OCT parameters were evaluated. The mean DRIL length was 463 ± 324 μm. The mean disruption length of EZ and ELM was 367 ± 247 μm and 414 ± 327 μm, respectively. The final mean SFT was 290 ± 91 μm. SRF presence at the initial visit was found to be associated with elongated EZ and ELM disruption length at the final visit (P = 0.03 and P = 0.04, respectively). On linear regression analyses, none of the baseline features (SRF, SFT, and HRIL) except baseline poor best corrected visual acuity were found to be predictive in anticipating the final visual outcome (P = 0.04). On linear bivariate analysis, the final poor visual outcome was found to be affected by EZ disruption length of ≥500 μm at the last visit (P = 0.02).

Conclusion

Baseline VA was the only predictive factor in anticipating the final visual outcome. At the final visit, extensive disruption length of EZ in the subfoveal area was associated with a poor visual outcome.

Automatic Segmentation of Retinal Layer in OCT Images With Choroidal Neovascularization

Age-related macular degeneration is one of the main causes of blindness. However, the internal structures of retinas are complex and difficult to be recognized due to the occurrence of neovascularization. Traditional surface detection methods may fail in the layer segmentation. In this paper, a supervised method is reported for simultaneously segmenting layers and neovascularization. Three spatial features, seven gray-level-based features, and 14 layer-like features are extracted for the neural network classifier. The coarse surfaces of different optical coherence tomography (OCT) images can thus be found. To describe and enhance retinal layers with different thicknesses and abnormalities, multi-scale bright and dark layer detection filters are introduced. A constrained graph search algorithm is also proposed to accurately detect retinal surfaces. The weights of nodes in the graph are computed based on these layer-like responses. The proposed method was evaluated on 42 spectral-domain OCT images with age-related macular degeneration. The experimental results show that the proposed method outperforms state-of-the-art methods.

Optical Coherence Tomography Measurement and Visual Outcome in Acute Central Retinal Artery Occlusion

Purpose

This study investigated visual acuity (VA) values and differences depending on optical coherence tomography (OCT) findings in patients with acute central retinal artery occlusion (CRAO).

Methods

A retrospective chart review was performed on patients with acute CRAO who underwent macular and disc OCT. We evaluated changes in macular thickness and retinal nerve fiber layer (RNFL) thickness after acute CRAO onset based on OCT. We also determined the association of thickness changes with VA improvement.

Results

This study involved both eyes in a total of 12 patients with acute CRAO. A significant increase was observed in foveal (1 mm) thickness (p = 0.002), parafoveal (3 mm) thickness (p = 0.002), and peripapillary RNFL thickness (p = 0.005) in affected eyes with CRAO, but not in central foveal thickness (p = 0.266). A significant small difference in both eyes (affected eye – fellow eye) was shown in foveal (1 mm) and mean parafoveal (3 mm) thickness in the improved VA group (p = 0.008 and p = 0.004, respectively), but not in central foveal or peripapillary RNFL thickness (both p = 0.283).

Conclusions

Both macular and RNFL thickness increased in patients with acute CRAO. RNFL thickness decreased over time with progression of RNFL atrophy. Less macular damage caused by acute CRAO could be predicted by a small difference in macular thickness between eyes (affected eye – fellow eye). In such cases, patients had a greater chance of VA improvement.

Relationship between Optical Intensity on Optical Coherence Tomography and Retinal Ischemia in Branch Retinal Vein Occlusion

Branch retinal vein occlusion (BRVO) may be complicated with retinal ischemia in some cases. The purpose of the current study is to investigate the relationship between optical intensity on optical coherence tomography (OCT) and retinal ischemia in BRVO. Twenty-seven eyes diagnosed with BRVO without macular edema were classified into two groups based on the presence or absence of retinal ischemia. The optical intensity of inner retinal layers and photoreceptor inner segment ellipsoid zone/retinal pigment epithelium layer (ISe/RPE) in the affected and unaffected regions were measured on OCT. Their ratio (Optical intensity ratio, OIR) was calculated and compared between affected and unaffected region. In the retinal ischemia group, the optical intensity of inner retinal layers was higher in the affected region compared to the unaffected region while the optical intensity of ISe/RPE was low. The OIR was significantly higher in the affected region compared to control (0.83 ± 0.17 vs 0.68 ± 0.09, p < 0.001). However, in the non-ischemic group, there was no significant difference between the affected and unaffected region. The BCVA was moderately correlated with OIR of affected region (r = 0.489, p = 0.010). Our study suggests that optical intensity ratio on OCT is correlated with retinal ischemia in BRVO.

Development of macular retinoschisis long after the onset of retinal arterial occlusion (RAO): a retrospective study

BACKGROUND

To describe a retrospective study of macular retinoschisis that developed long after the onset of retinal artery occlusion (RAO) using optical coherence tomography (OCT).

METHODS

We describe changes in macular findings and visual acuity (VA) of 29 patients (21 males and 8 females, mean age: 66.1 ± 16.9 years) with RAO (18 branch RAOs [BRAOs] and 11 central RAOs [CRAOs] who visited Osaka Medical College Hospital over an 8-year period based on a medical chart review.

RESULTS

The mean VA (logMAR) increased from 1.06 ± 1.08 (CRAO: 2.04 ± 0.99; BRAO: 0.37 ± 0.40) at the first visit to 0.71 ± 0.87 (CRAO: 1.46 ± 0.86; BRAO: 0.18 ± 0.30) at the final visit. Macular OCT revealed swelling or hyper-reflectivity of the inner retina in the early phase of RAO and retinal thinning in the late phase. Among the 29 patients, two patients (a patient with BRAO and a patient with CRAO) developed macular retinoschisis about 1 year after RAO onset. The VA of the patient with BRAO was 20/300 at the first visit, and it improved to 20/25 two days after onset following eye massage and anterior chamber paracentesis. However, his VA worsened, declining from 20/25 to 20/50, and retinoschisis occurred 13 months after RAO onset. The patient with CRAO showed macular changes including small cystoids at the first follow-up visit more than 3 weeks after onset and developed retinoschisis 11 months after the first visit. In addition, two patients with BRAO and one patient with CRAO developed macular changes including small cystoids 3 weeks after onset, with the BRAO complicated by retinal vein occlusion. In the CRAO patient, the cystoid macular edema was resolved 1 month after the first visit.

CONCLUSIONS

Macular retinoschisis is unusual, but a possible complication of RAO that can develop long after the onset of the occlusion, potentially resulting in renewed VA deterioration.

Changes of outer retinal microstructures after photodynamic therapy for chronic central serous chorioretinopathy

PURPOSE

To evaluate the morphological changes in retinal microstructures following modified photodynamic therapy (PDT) for chronic central serous chorioretinopathy.

SUBJECTS AND METHODS

Retrospective study of 21 consecutive eyes (age, 59±8.0 years [mean ± SD]) of 21 patients with chronic central serous chorioretinopathy. Inner foveal thickness (the distance between the internal limiting membrane and external limiting membrane), photoreceptor outer segment (PROS) length at the point without serous retinal detachment and choroidal thickness were assessed with enhanced depth imaging optical coherence tomography before treatment and at 1, 3 and 6 months after modified PDT.

RESULTS

Six eyes had half-dose and 15 eyes had half-fluence PDT. PROS length within the irradiated area was significantly decreased by 3.9% at 1 month compared with that before modified PDT (43.5±5.72 and 40.5±7.53, P=0.020 [paired t-test]) and returned to baseline length at 3 and 6 months (43.0±5.42 and 43.5±4.33 μm [mean ± SD]; P=0.53 and 1.00 [paired t-test]). PROS length of the nonirradiated area at 1, 3 and 6 months after modified PDT did not significantly differ from that before PDT (41.8±6.35, 41.4±5.33, 41.9±4.67 and 42.3±4.26 μm [mean ± SD]; P=0.66, 0.90 and 0.60, respectively [paired t-test]). There was no significant change in inner foveal thickness during the observation period. At all time points, choroidal thickness was significantly thinner than it was before PDT (P<0.001, paired t-test).

CONCLUSION

Modified PDT may cause mild temporary microstructural changes.

Atrophy of retinal inner layers is associated with poor vision after endophthalmitis: a spectral domain optical coherence tomography study

PurposeTo investigate the retinal structural changes in endophthalmitis and their association with visual outcome.Patients and methodsForty-five eyes of 45 patients diagnosed with endophthalmitis were included. Spectral domain optical coherence tomography (SD-OCT) was performed after inflammation was controlled. The relationship between SD-OCT features and best-corrected visual acuity (BCVA) at the last follow-up was analyzed.ResultsThe structural changes included inner segment ellipsoid (ISe) disruption (49%), atrophy of retinal inner layers (24%), epimacular membrane (24%), and macular edema (24%). BCVA was worse in patients with ISe disruption (P=0.005) and retinal inner layers' atrophy (P=0.004) compared with those without. There was no significant difference of BCVA between the patients with and without epimacular membrane, or intraretinal cysts. Multivariate regression showed that atrophy of retinal inner layers (b=0.41±0.17, P=0.022) was the only independent factor associated with BCVA.ConclusionAtrophy of retinal inner layers is associated with visual impairment in endophthalmitis, despite successful management.

Central Retinal Artery Occlusion: Acute Management and Treatment

PURPOSE OF REVIEW

This review will seek to answer if advances in ophthalmic imaging and evolution of treatment modalities have shed further light on the epidemiology, pathophysiology, diagnosis, and acute management of acute CRAO.

RECENT FINDINGS

Imaging characteristics of acute CRAO have been further characterized with the use of fluorescein angiography, optical coherence tomography (OCT), OCT-angiography, and indocyanine-green angiography. Layer segmentation of OCT imaging has found inner retinal layer hyper-reflectivity to be a common finding in acute CRAO. Non-invasive therapies, fibrinolytic delivery, and surgical interventions for acute CRAO have been further evaluated as potential management tools.

SUMMARY

A large body of literature reports very inconsistent treatment success with a wide variety of modalities. Currently, there is no clear evidence supporting the use of fibrinolytics in acute CRAO. Large, multicenter, randomized control trials are necessary to elucidate the role of the various acute treatment options in the management of CRAO.