RETINAL VASCULAR CYSTOID MACULAR EDEMA: Review and New Theory

Macular edema after rhegmatogenous retinal detachment repair: risk factors, OCT analysis, and treatment responses

PURPOSE

To investigate risk factors, imaging characteristics, and treatment responses of cystoid macular edema (CME) after rhegmatogenous retinal detachment (RRD) repair.

METHODS

Consecutive, retrospective case-control series of patients who underwent pars plana vitrectomy (PPV) and/or scleral buckling (SB) for RRD, with at least six months of follow-up. Clinical and surgical parameters of patients with and without CME (nCME), based on spectral-domain optical coherence tomography (OCT), were compared.

RESULTS

Of 99 eyes enrolled, 25 had CME while 74 had nCME. Patients with CME underwent greater numbers of surgeries (P < 0.0001). After adjusting for number of surgeries, macula-off RRD (P = 0.06), proliferative vitreoretinopathy (PVR) (P = 0.09), surgical approach (PPV and/or SB, P = 0.21), and tamponade type (P = 0.10) were not statistically significant, although they all achieved significance on univariate analysis (P = 0.001 or less). Intraoperative retinectomy (P = 0.009) and postoperative pseudophakia or aphakia (P = 0.008) were more frequent in the CME group, even after adjustment. Characteristics of cCME on OCT included diffuse distribution, confluent cysts, and absence of subretinal fluid or intraretinal hyperreflective foci. Macular thickness improved significantly with intravitreal triamcinolone (P = 0.016), but not with anti-vascular endothelial growth factor agents (P = 0.828) or dexamethasone implant (P = 0.125). After adjusting for number of surgeries and macular detachment, final visual acuities remained significantly lower in the CME vs nCME group (P = 0.012).

CONCLUSION

Risk factors of CME include complex retinal detachment repairs requiring multiple surgeries, and pseudophakic or aphakic lens status. Although this cCME was associated with poor therapeutic response, corticosteroids were the most effective studied treatments.

Vessel Density Changes on Optical Coherence Tomography Angiography after Vascular Endothelial Growth Factor Inhibitor Treatment for Diabetic Macular Edema

Objectives

To evaluate the changes in macular vessel density after treatment with vascular endothelial growth factor (VEGF) inhibitors in center-involving diabetic macular edema (DME) and to compare these changes between anatomical responders and non-responders.

Materials and Methods

This retrospective study included 22 eyes with center-involving DME. All eyes had 3 consecutive administrations of VEGF inhibitors. Optical coherence tomography (OCT) and OCT angiography (OCTA) of the macula with manual adjustment of segmentation lines were performed at baseline and after treatment. Vessel density in the central and parafoveal regions of the superficial and deep capillary plexus (SCP/DCP) were measured at baseline and after treatment. Vessel density and changes therein were compared between anatomical responders and non-responders as defined by changes in central subfield thickness (CST).

Results

Overall, there were no significant differences in vessel density in the central and parafoveal regions of the SCP and DCP after treatment compared to baseline. After categorization by anatomical response, 12 eyes were responders (CST decreased by 173.7±47.7 μm) and 10 eyes were non-responders (CST increased by 20.8±38.9 μm) (p<0.0001). There were no corresponding significant differences between responders and non-responders in SCP and DCP vessel density or changes therein after treatment.

Conclusion

There were no significant changes in macular vessel density after the early stages of VEGF inhibitor treatment for DME, and there was no relationship with the anatomical response. The effect of VEGF inhibitors in DME treatment may not be related to increasing vessel density.

Retinal Microcirculation and Cytokines as Predictors for Recurrence of Macular Edema after Intravitreal Ranibizumab Injection in Branch Retinal Vein Occlusion

Purpose: To investigate the relationship between retinal blood flow, presence or absence of recurrence of macular edema, and levels of cytokines, after intravitreal ranibizumab injection (IRI) in patients with branch retinal vein occlusion (BRVO). Methods: In 47 patients with BRVO and macular edema, we used laser speckle flowgraphy (LSFG) to measure the relative flow volume (RFV) of the retinal arteries and veins passing through the optic disc in the occluded and non-occluded regions of the retina before and after IRI. Aqueous humor samples were obtained at the time of IRI. Levels of vascular endothelial growth factor (VEGF), soluble VEGF receptor (sVEGFR)-1, sVEGFR-2, placental growth factor (PlGF), platelet-derived growth factor (PDGF)-AA, soluble intercellular adhesion molecule (sICAM)-1, monocyte chemoattractant protein 1 (MCP-1), interleukin (IL)-6, IL-8, IL-12 (p70), IL-13 and interferon-inducible 10-kDa protein (IP-10) were measured by the suspension array method. Patients were categorized into two groups on the basis of whether or not macular edema recurred at 2 months after IRI: the nonrecurrent group, n = 24; and the recurrent group, n = 23. Results: In the veins of the occluded region, RFV showed a significant difference between baseline and 1 month after IRI (p < 0.001) in the recurrent group and the percent change of RFV showed a significant difference between the recurrent and nonrecurrent groups (p = 0.005). Furthermore, we found a significant negative correlation between RFV in the veins of the occluded region and aqueous levels of MCP-1, IL-8 and IP-10 at baseline (p = 0.029, p = 0.035, and p = 0.039, respectively). In the recurrent group, the arteries and veins of the non-occluded and occluded regions showed no significant association between RFV and the aqueous levels of any factors. Conclusions: These findings suggested that a decrease in RFV in the veins of the occluded region might be associated with the recurrence of macular edema and that the recurrence might depend on the change in RFV in the veins of the occluded region rather than the levels of cytokines.

Optical Coherence Tomographic Patterns as Predictors of Structural Outcome After Intravitreal Ranibizumab in Diabetic Macula Edema

Background/Objectives

The purpose of this study was to present an association between the treatment response of diabetic macular edema (DME) to intravitreal ranibizumab (IVR) injections and different morphology patterns using spectral domain optical coherence tomography (SD-OCT).

Subjects/Methods

This retrospective study included 216 eyes of 142 subjects who received IVR for DME and were observed for at least 2 years. Medical charts and SD-OCT images of consecutive patients were reviewed at baseline, 1, 3, 6, 12, and 24 months after first IVR treatment. The OCT patterns were characterized as diffuse retinal thickening (DRT), cystoid macular edema (CME), serous retinal detachment (SRD), and vitreomacular interface abnormalities (VMIAs). All patients were classified into four groups based on the OCT findings.

Results

For a total of 216 eyes, 36 eyes were classified into the DRT group, 76 in the CME group, 42 in the SRD group, and 62 in the VMIA group. There were significant central macula thickness (CMT) improvements in all groups at the 1st month and the 2nd year, except for the DRT group at the 2nd year. Patients with OCT findings of hyperreflective dots (HRDs), metabolic parameters of hyperlipidemia, and coronary artery disease (CAD) had significantly less improvements in CMT at 2-year follow-up (P=0.029, 0.007, <0.001, respectively).

Conclusion

A trend toward decreased effectiveness after long-term IVR treatment was observed in the DRT group. Consistent IVR treatment could still achieve favorable improvement in the reduction of CMT in 2-year follow-up in the VMIA group. Different OCT patterns in DME may affect the therapeutic role of anti-VEGF agents and predict the structure outcome.

Disorganisation of retinal inner layers is associated with reduced contrast sensitivity in retinal vein occlusion

BACKGROUND/AIMS

To determine if disorganisation of retinal inner layers (DRIL) is associated with reduced contrast sensitivity (CS) in patients with retinal vein occlusion (RVO) with a history of macular oedema (ME).

METHODS

Prospective, observational cohort study. Patients with a history of ME secondary to central retinal vein occlusion (CRVO) or branch retinal vein occlusion (BRVO) from October 2017 to July 2019 at a single institution were included. Patients underwent complete ophthalmic examination, spectral domain optical coherence tomography (SD-OCT) and CS testing using the quick contrast sensitivity function (qCSF) method. Eyes with coexisting macular disease were excluded. SD-OCT images were analysed for presence and extent of DRIL, intraretinal fluid (IRF), subretinal fluid (SRF), hyperreflective foci, epiretinal membrane (ERM), external limiting membrane (ELM) disruption, ellipsoid zone (EZ) disruption, central macular thickness (CMT) and central foveal thickness (CFT). Multivariable mixed-effect linear regressions were performed for the area under the log contrast sensitivity function (AULCSF) using Stata (StataCorp). P values <0.05 were considered significant.

RESULTS

58 visits from 31 patients were included (1.9±1.2 visits per patient). 29 (50%) were for CRVO. The average age was 63.9±10.5 years. On multivariable analysis, DRIL extent (p<0.001), CMT (p=0.007), CFT (p=0.024) and moderate cataract (p=0.001) were significantly associated with worse AULCSF.

CONCLUSIONS

DRIL extent is associated with reduced CS in eyes with ME secondary to RVO. DRIL is an imaging feature that has important implications for visual function.

Treatment of Intraretinal Cystic Spaces Associated With Gyrate Atrophy of the Choroid and Retina With Intravitreal Bevacizumab

PURPOSE

To evaluate the use of intravitreal bevacizumab injections for the treatment of intraretinal cystic spaces associated with gyrate atrophy of the choroid and retina.

METHODS

Retrospective chart review of 5 eyes of 3 patients with intraretinal cystic spaces associated with gyrate atrophy and treated with intravitreal bevacizumab injections was performed. Information obtained included history, examination findings, optical coherence tomography (OCT), OCT angiography, fluorescein angiography, and microperimetric findings before and after the injections.

RESULTS

The mean age of patients was 11 ± 4.6 years. All patients received three monthly bevacizumab injections. The mean corrected distance visual acuity was 0.27 ± 0.10 at baseline and improved to 0.36 ± 0.12 after the injections (P = .015). The mean central macular thickness was 569 ± 127 µm at baseline and improved to 422 ± 123 µm after the injections (P = .067). Microperimetry and OCT angiography performed in 1 patient before and after the three injections showed improved macular sensitivity and vascular density measurements following the injections.

CONCLUSIONS

Intravitreal bevacizumab is safe and effective in the treatment of intraretinal cystic spaces associated with gyrate atrophy. [J Pediatr Ophthalmol Strabismus. 2020;57(6):400-406.].

Characterization of microvascular tortuosity in retinal vein occlusion utilizing optical coherence tomography angiography

We investigated the characteristics of microvessel tortuosity in branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) and their associations with visual outcomes using optical coherence tomography angiography (OCTA). Thirty-four BRVO and 21 CRVO patients and 31 healthy subjects were included. From OCTA, the branch number (BN), mean branch length (BL), mean Euclidean length (EL), vessel density (VD) and vessel tortuosity (VT) were quantified. In BRVO eyes, compared with that in the controls, the affected area of the deep capillary plexus (DCP) showed a decreased BN and VD, an increased BL, and unchanged VT. The nonaffected area of the DCP showed decreases in BN, VD and VT. The affected area of the superficial capillary plexus (SCP) showed higher VT. In CRVO eyes, the DCP showed a lower BN, VD and VT, while the SCP showed a lower BN and greater BL and EL. Improved visual acuity (VA) after 1 year in BRVO eyes was associated with decreases in BN, BL, VD and VT in the affected area in the DCP and lower VT in the nonaffected area of the SCP; in CRVO eyes, improved VA was associated with a higher BL and EL in the DCP. VT, BL, and EL may be new microvascular markers associated with changes in VA in BRVO and CRVO.

Effect of Dexamethasone Intravitreal Implant on Visual Acuity and Foveal Photoreceptor Integrity in Macular Edema Secondary to Retinal Vascular Disease

PURPOSE

The aim of this study was to evaluate the effect of the dexamethasone intravitreal (DEX) implant on the external limiting membrane (ELM) and ellipsoid zone (EZ) integrity in treatment-naïve patients with macular edema (ME) secondary to retinal vascular disease (RVD).

METHODS

This is a retrospective study conducted on patients with ME secondary to RVD, who underwent a DEX implant.

RESULTS

One-hundred eyes were included. Mean age was 70.3 ± 11.1 years. Mean ELM integrity significantly improved from 1,575.9 ± 285.9 μm at baseline to 1,711.7 ± 244.0 μm at month 3 (p < 0.0001). Similarly, there was a significant improvement in EZ integrity from baseline to month 3 (1,531.5 ± 317.1 vs. 1,694.3 ± 252.8 μm, respectively, p < 0.0001). At month 3, mean visual acuity (VA) gain was 9.9 ± 14.1 letters (p < 0.0001). Mean central retinal thickness (CRT) significantly decreased by -193.2 ± 185.7 μm from baseline to month 3 (p < 0.0001). Mean changes in VA and CRT were significantly correlated with baseline ELM integrity (p = 0.0065 and p = 0.0046, respectively) and EZ integrity (p = 0.0300 and p = 0.0035, respectively). At month 3, the proportion of eyes which had an intact ELM (mean difference 16.0%, 95% CI 5.4-26.4%, p = 0.0033) and EZ (mean difference 12.0%, 95% CI 1.8-22.1%, p = 0.0210) was significantly higher than at baseline.

CONCLUSIONS

DEX implant was able to significantly improve ELM and EZ integrity in naïve patients with ME.

Automated Segmentation of Retinal Fluid Volumes From Structural and Angiographic Optical Coherence Tomography Using Deep Learning

Purpose

We proposed a deep convolutional neural network (CNN), named Retinal Fluid Segmentation Network (ReF-Net), to segment retinal fluid in diabetic macular edema (DME) in optical coherence tomography (OCT) volumes.

Methods

The 3- × 3-mm OCT scans were acquired on one eye by a 70-kHz OCT commercial AngioVue system (RTVue-XR; Optovue, Inc., Fremont, CA, USA) from 51 participants in a clinical diabetic retinopathy (DR) study (45 with retinal edema and six healthy controls, age 61.3 ± 10.1 (mean ± SD), 33% female, and all DR cases were diagnosed as severe NPDR or PDR). A CNN with U-Net-like architecture was constructed to detect and segment the retinal fluid. Cross-sectional OCT and angiography (OCTA) scans were used for training and testing ReF-Net. The effect of including OCTA data for retinal fluid segmentation was investigated in this study. Volumetric retinal fluid can be constructed using the output of ReF-Net. Area-under-receiver-operating-characteristic-curve, intersection-over-union (IoU), and F1-score were calculated to evaluate the performance of ReF-Net.

Results

ReF-Net shows high accuracy (F1 = 0.864 ± 0.084) in retinal fluid segmentation. The performance can be further improved (F1 = 0.892 ± 0.038) by including information from both OCTA and structural OCT. ReF-Net also shows strong robustness to shadow artifacts. Volumetric retinal fluid can provide more comprehensive information than the two-dimensional (2D) area, whether cross-sectional or en face projections.

Conclusions

A deep-learning-based method can accurately segment retinal fluid volumetrically on OCT/OCTA scans with strong robustness to shadow artifacts. OCTA data can improve retinal fluid segmentation. Volumetric representations of retinal fluid are superior to 2D projections.

Translational Relevance

Using a deep learning method to segment retinal fluid volumetrically has the potential to improve the diagnostic accuracy of diabetic macular edema by OCT systems.

Preclinical and clinical studies of photobiomodulation therapy for macular oedema

AIMS/HYPOTHESIS

Diabetic macular oedema (DME) is the leading cause of visual impairment in people with diabetes. Intravitreal injections of vascular endothelial growth factor inhibitors or corticosteroids prevent loss of vision by reducing DME, but the injections must be given frequently and usually for years. Here we report laboratory and clinical studies on the safety and efficacy of 670 nm photobiomodulation (PBM) for treatment of centre-involving DME.

METHODS

The therapeutic effect of PBM delivered via a light-emitting diode (LED) device was tested in transgenic mice in which induced Müller cell disruption led to photoreceptor degeneration and retinal vascular leakage. We also developed a purpose-built 670 nm retinal laser for PBM to treat DME in humans. The effect of laser-delivered PBM on improving mitochondrial function and protecting against oxidative stress was studied in cultured rat Müller cells and its safety was studied in pigmented and non-pigmented rat eyes. We then used the retinal laser to perform PBM in an open-label, dose-escalation Phase IIa clinical trial involving 21 patients with centre-involving DME. Patients received 12 sessions of PBM over 5 weeks for 90 s per treatment at a setting of 25, 100 or 200 mW/cm² for the three sequential cohorts of 6-8 patients each. Patients were recruited from the Sydney Eye Hospital, over the age of 18 and had centre-involving DME with central macular thickness (CMT) of >300 μm with visual acuity of 75-35 Log minimum angle of resolution (logMAR) letters (Snellen visual acuity equivalent of 20/30-20/200). The objective of this trial was to assess the safety and efficacy of laser-delivered PBM at 2 and 6 months. The primary efficacy outcome was change in CMT at 2 and 6 months.

RESULTS

LED-delivered PBM enhanced photoreceptor mitochondrial membrane potential, protected Müller cells and photoreceptors from damage and reduced retinal vascular leakage resulting from induced Müller cell disruption in transgenic mice. PBM delivered via the retinal laser enhanced mitochondrial function and protected against oxidative stress in cultured Müller cells. Laser-delivered PBM did not damage the retina in pigmented rat eyes at 100 mW/cm². The completed clinical trial found a significant reduction in CMT at 2 months by 59 ± 46 μm (p = 0.03 at 200 mW/cm²) and significant reduction at all three settings at 6 months (25 mW/cm²: 53 ± 24 μm, p = 0.04; 100 mW/cm²: 129 ± 51 μm, p < 0.01; 200 mW/cm²: 114 ± 60 μm, p < 0.01). Laser-delivered PBM was well tolerated in humans at settings up to 200 mW/cm² with no significant side effects.

CONCLUSIONS/INTERPRETATION

PBM results in anatomical improvement of DME over 6 months and may represent a safe and non-invasive treatment. Further testing is warranted in randomised clinical trials.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02181400 Graphical abstract.

Correlation between macular edema recurrence and macular capillary network destruction in branch retinal vein occlusion

BACKGROUND

The aim of this study was to evaluate the correlation between changes in the macular capillary network and macular edema (ME) recurrence with branch retinal vein occlusion (BRVO) using swept-source optical coherence tomography angiography (SS-OCTA).

METHODS

We reviewed the data for 43 patients with treatment-naïve ME associated with BRVO. Patients who received intravitreal bevacizumab injection were divided into two groups based on ME recurrence at 6 months after edema resolution. The perifoveal capillary morphology and the macular capillary vessel density (VD) were retrospectively analyzed using en face SS-OCTA after ME resolution.

RESULTS

The perifoveal capillary ring loss in the superficial capillary plexus (SCP) and deep capillary plexus (DCP) was more common in the ME recurrence group (n = 22) than in the no ME recurrence group (p = 0.047 and p = 0.002). Relative to the findings in the no ME recurrence groups, the destruction of the perifoveal capillary ring was more severe in the DCP (30.0° vs 87.3°, p = 0.001) than in the SCP (17.3° vs 69.5°, p = 0.006) in the ME recurrence group. The hemi-VD disparity between the affected and the unaffected areas in the SCP and DCP showed significant differences (p = 0.031 and p = 0.017), while macular VD showed no differences between the groups.

CONCLUSIONS

Destruction of the perifoveal capillary ring and hemi-VD disparity could be related to ME recurrence in BRVO. Therefore, these factors may be helpful in predicting ME recurrence.

Macular microvascular changes after intravitreal bevacizumab injection in diabetic macular edema

OBJECTIVE

To evaluate the changes in retinal capillary plexus and the choriocapillaris after a single intravitreal injection of bevacizumab in eyes with diabetic macular edema using optical coherence tomography angiography (OCTA).

DESIGN

Prospective interventional case series.

PARTICIPANTS

Patients having diabetes with centre-involving diabetic macular edema.

METHODS

In this prospective interventional case series, eyes with centre-involving diabetic macular edema were enrolled. Vascular density (VD), vascular diameter index (VDI), vascular length density (VLD), foveal avascular zone (FAZ) area, and foveal density (FD)-300 were measured using en face OCTA images before and 1 month after administration of intravitreal bevacizumab. VD and VDI measurements were performed in the superficial capillary plexus (SCP) and deep retinal capillary plexus (DCP) and in the choriocapillaris. Additionally, capillary nonperfusion area (CNPA) was detected automatically based on vessel distance map in 4 concentric rings around the foveal centre. The segmentation error was manually corrected, and the measurements were performed by 2 expert graders.

RESULTS

Twenty-three eyes of 19 patients with a mean age of 62.76 ± 6.88 years were included. There were no significant changes in the FAZ area, FD-300, or in the VD of the foveal and parafoveal SCP and DCP. Also, VLD and VDI of the SCP and DCP remained unchanged. The change in the CNPA was not statistically significant. The VD of choriocapillaris increased significantly after injections (p = 0.005).

CONCLUSIONS

FAZ area and VD of the retinal capillary plexus remained stable in the short-term period after intravitreal bevacizumab. In addition, the choriocapillaris blood flow improved after bevacizumab injection.

Longitudinal Development of Peripapillary Hyper-Reflective Ovoid Masslike Structures Suggests a Novel Pathological Pathway in Multiple Sclerosis

OBJECTIVE

Peripapillary hyper-reflective ovoid masslike structures (PHOMS) are a new spectral domain optical coherence tomography (OCT) finding.

METHODS

This prospective, longitudinal study included patients (n = 212) with multiple sclerosis (MS; n = 418 eyes), 59 healthy controls (HCs; n = 117 eyes), and 267 non-MS disease controls (534 eyes). OCT and diffusion tensor imaging were used.

RESULTS

There were no PHOMS in HC eyes (0/117, 0%). The prevalence of PHOMS was significantly higher in patients with MS (34/212, p = 0.001) and MS eyes (45/418, p = 0.0002) when compared to HCs (0/59, 0/117). The inter-rater agreement for PHOMS was 97.9% (kappa = 0.951). PHOMS were present in 16% of patients with relapsing-remitting, 16% of patients with progressive, and 12% of patients with secondary progressive disease course (2% of eyes). There was no relationship of PHOMS with age, disease duration, disease course, disability, or disease-modifying treatments. The fractional anisotropy of the optic radiations was lower in patients without PHOMS (0.814) when compared to patients with PHOMS (0.845, p = 0.03). The majority of PHOMS remained stable, but increase in size and de novo development of PHOMS were also observed. In non-MS disease controls, PHOMS were observed in intracranial hypertension (62%), optic disc drusen (47%), anomalous optic discs (44%), isolated optic neuritis (19%), and optic atrophy (12%).

INTERPRETATION

These data suggest that PHOMS are a novel finding in MS pathology. Future research is needed to determine whether development of PHOMS in MS is due to intermittently raised intracranial pressure or an otherwise impaired "glymphatic" outflow from eye to brain. ANN NEUROL 2020;88:309-319.

Identification of epiretinal proliferation in various retinal diseases and vitreoretinal interface disorders

Background

To describe the presence of epiretinal proliferation in eyes with various retinal and vitreoretinal interface conditions.

Methods

Consecutive patients seen at the Stein Eye Institute, by one retina specialist, from December 2018 to March 2019, and demonstrating epiretinal proliferation on optical coherence tomography (OCT) were enrolled in this cross-sectional study. Included patients were divided into two groups: vitreoretinal interface pathologies group or retinal diseases group. Presence of epiretinal proliferation and its localization within the 9 macular sectors, as defined by the Early Treatment Diabetic Retinopathy Study (ETDRS), were assessed on OCT.

Results

77 eyes from 69 patients demonstrated epiretinal proliferation on OCT. The most frequently involved ETDRS sector was the 1-mm central subfield, followed by inner temporal and inner nasal sectors. Localization of epiretinal proliferation correlated with the presence of any retinal abnormalities in the same quadrant (r = 0.962; P < 0.0001). 31 eyes (40.3%) demonstrated symptomatic vitreoretinal interface pathologies including lamellar macular hole, full-thickness macular hole, epiretinal membrane and history of macular peeling. 46 eyes (59.7%) manifested various retinal diseases, including age-related macular degeneration, diabetic retinopathy, refractory macular edema, vein occlusion and high myopia.

Conclusions

Epiretinal proliferation was noted in several retinal conditions and not limited only to full-thickness and lamellar macular holes. Different mechanisms affecting retinal homeostasis might trigger Müller cells dysregulation, potentially leading to abnormal retinal remodeling.

Acute retinal necrosis following dexamethasone intravitreal implant (Ozurdex®) administration in an immunocompetent adult with a history of HSV encephalitis: a case report

Background

Dexamethasone intravitreal implants (0.7 mg) (Ozurdex®, Allergan Inc., Madison, NJ) are FDA approved for managing macular oedema (ME) of retinal vein occlusion (RVO). The major complications associated with intravitreal Ozurdex® implant include increased intraocular pressure and cataract progression. In regard to the occurrence of retinal complications, we report an unusual intravitreal Ozurdex® implantation-related acute retinal necrosis (ARN).

Case presentation

A 45-year-old immunocompetent woman with a history of encephalitis presented with photophobia, redness, floaters, and rapidly decreased vision in her left eye. Three and six months ago, she received two doses of intravitreal Ozurdex® implant for ME of RVO. Clinical evaluation, including slit-lamp biomicroscopy, retinal photography, and fluorescein angiography, revealed anterior chamber cells, granulomatous keratic precipitates, cells in the vitreous, optic disc oedema, occlusive retinal vasculitis, scattered retinal haemorrhages, one quadrant of peripheral white areas with retinal necrosis, optic disc and vessels fluorescein staining, and retinal nonperfusion zones. All the above clinical manifestations showed an ARN. Herpes simplex virus was detected in the aqueous and vitreous humour by quantitative polymerase chain reaction testing. Intravenous acyclovir 500 mg tid for 7 days followed by oral valcyclovir was immediately performed for ARN. At 4 months, the patient’s condition improved without retinal detachment, and the best-corrected visual acuity remained stable at 0.3.

Conclusions

ARN might represent a risk of Ozurdex® administration.

Cytokines and Growth Factors as Predictors of Response to Medical Treatment in Diabetic Macular Edema

Diabetic macular edema (DME) is the most common cause of visual loss in patients with diabetes. Antivascular endothelial growth factors (anti-VEGF) agents are first-line therapy for DME. Nevertheless, up to 60% of patients (depending on the anti-VEGF drug used) have an inadequate response to anti-VEGF treatment. Several cytokines are increased in aqueous humor of patients with DME. Differences in response to treatment may be related to baseline cytokine levels. Intravitreal corticosteroids may be used as an alternative to anti-VEGF agents. Steroids have a different pharmacological profile and act on different pathophysiologic mechanisms. Their effect on aqueous humor cytokines is different from the effect of anti-VEGF therapy. This review highlights the major cytokines involved in DME and evaluates whether baseline cytokine levels could be predictors of response to treatment in DME. SIGNIFICANCE STATEMENT: Antivascular endothelial growth factor (anti-VEGF) agents are efficient as diabetic macular edema (DME) treatment. However, in some cases, DME fails to respond to anti-VEGF intravitreal injections. Changes in cytokine levels after treatment supported the idea that other cytokines than VEGF are implicated in DME pathogenesis and could be predictors of response to anti-VEGF treatment or corticosteroids allowing targeted and individualized therapy guided by cytokine levels.

Glaucomatous vertical vessel density asymmetry of the temporal raphe detected with optical coherence tomography angiography

Changes in retinal vasculature and ocular circulation may play an important role in the glaucoma development and progression. We evaluated the vertical asymmetry across the temporal raphe of the deep retinal layer vessel density, using swept-source optical coherence tomography angiography (SS-OCTA), and its relationship with the central visual field (VF) loss. Thirty-four eyes of 27 patients with open-angle glaucoma were included. SS-OCTA macular scanning was performed within a 3 × 3 mm (300 × 300 pixels) volume, centred on the fovea. The relationships between the vertical asymmetrical deep retinal vessel density reduction (ADRVD) across the temporal raphe and various ocular parameters were analysed. Twenty-two glaucomatous eyes with ADRVDs had central VF loss. Contrarily, ADRVDs were not found in any of the 12 eyes without central VF loss. Thirteen eyes (59.1%) with central VF loss had ADRVDs topographically corresponding to the central VF loss and macular ganglion cell complex thinning. The glaucomatous eyes with ADRVDs exhibited inferior rather than superior central VF loss (P = 0.032). Thus, ADRVD specifically indicates the glaucomatous central visual loss. Further analysis of ADRVD may improve our understanding on glaucoma pathogenesis, offering new treatment insights.

Intravitreal injection of conbercept combined with retinal photocoagulation on macular edema secondary to branch retinal vein occlusion

Effects of Conbercept combined with retinal photocoagulation on macular edema secondary to branch retinal vein occlusion (BRVO) were investigated. A total of 98 patients (98 eyes) with macular edema secondary to BRVO were collected. The central macular thickness (CMT), incidence rate of complications after treatment and best corrected visual acuity (BCVA) were recorded. Also the factors affecting visual recovery of patients were analyzed. At 1 week, 1 month, 3 months and 6 months after treatment, the BCVA in both groups was significantly superior to that before treatment (P<0.05). In the combination group and laser group, the logarithm of the minimum angle of resolution (logMAR) of BCVA increased from 0.84±0.47 to 0.34±0.10 and from 0.89±0.49 to 0.45±0.14, and CMT declined from 559.5±152.7 to 267.8±19.8 µm and from 570.3±172.6 to 314.7±18.4 µm. It was observed that at 1 week, 1 month, 3 months and 6 months after treatment, the BCVA in combination group was obviously better than that in laser group (P=0.008, P<0.001, P=0.004, P<0.001, respectively), while CMT in combination group was obviously smaller than that in laser group (P=0.009, P=0.002, P<0.001, P<0.001). Conbercept with retinal photocoagulation can effectively improve the visual acuity and reduce the CMT. The visual recovery of patients after treatment is related to the BCVA before treatment, decreased value of CMT at 1 month after treatment and integrity of external limiting membrane (ELM).

Distinctive Mechanisms and Patterns of Exudative Versus Tractional Intraretinal Cystoid Spaces as Seen With Multimodal Imaging

PURPOSE

To determine clear-cut distinctions between tractional and exudative intraretinal cystoid spaces subtypes.

DESIGN

Retrospective, multicenter, observational case series.

METHODS

A cohort of patients diagnosed with intraretinal cystoid spaces and imaged with optical coherence tomography (OCT), fluorescein angiography (FA), blue fundus autofluorescence (BFAF), en face OCT, and OCT angiography (OCT-A) was included in the study. All images were qualitatively and quantitatively evaluated.

RESULTS

In this study were included 72 eyes of 69 patients. Exudative intraretinal cystoid spaces (36/72 eyes, 50%) displayed a "petaloid" morphology as seen with en face OCT, FA, and BFAF. Tractional intraretinal cystoid spaces (24/72 eyes, 33.3%), displayed a radial "spoke-wheel" en face OCT pattern. There was no leakage with FA and BFAF did not reveal specific patterns. Eyes with full-thickness macular hole (FTMH, 12/72 eyes, 16.7%) displayed a "sunflower" en face OCT appearance. FTMH showed OCT, OCT-A, and BFAF features of both exudative and tractional cystoid spaces, but without any FA leakage. Inner nuclear layer (INL) thickness was significantly lower in tractional cystoid spaces (P < .001). There were a greater number of INL cystoid spaces in both the exudative and FTMH subgroups (P = .001). The surface area of INL cystoid spaces was significantly lower in the tractional subgroup (P < .001). There was a significant reduction of the microvascular density in eyes with exudative vs tractional (P = .002) and FTMH (P < .001) subgroups.

CONCLUSIONS

Exudative and tractional intraretinal cystoid spaces displayed characteristic multimodal imaging features and they may represent 2 different pathologic conditions with equally different clinical implications.

Diabetic macular edema with neuroretinal detachment: OCT and OCT-angiography biomarkers of treatment response to anti-VEGF and steroids

PURPOSE

To assess and compare early changes in neuroinflammatory and vascular parameters in diabetic macular edema (DME) with subfoveal neuroretinal detachment (SND) after treatment with intravitreal dexamethasone (DEX-I) and ranibizumab (IVR).

METHODS

Thirty-three eyes (33 patients) with treatment naïve DME with SND were retrospectively evaluated at baseline and 2 months after DEX-I (15 eyes) and 1 month after 3 monthly IVR injections (18 eyes). Inclusion criteria were: complete eye examination, good quality OCT and OCT-A images. OCT parameters included: central macular thickness (CMT); number of hyper-reflective retinal spots (HRS) in inner, outer (IR, OR) and full retina; choroidal thickness (CT), extent of disorganization of inner retinal layers (DRIL), outer retina integrity (OR). On OCT-A: foveal avascular zone (FAZ) parameters in the superficial capillary plexus (SCP); cysts area and perfusion density (PD) in SCP and deep capillary plexus (DCP) and flow voids (FV) in choriocapillaris. FAZ was analyzed using ImageJ, perfusion parameters and FV using MATLAB.

RESULTS

BCVA increased equally after both treatments (13.0 ± 10.0 ETDRS letters, p < 0.0001). There was a similar decrease (p < 0.05) in: height of SND, cysts area at SCP, central and mean CT, increase in FAZ perimeter and OR integrity, after both treatments. A greater decrease in DEX-I versus IVR group was found in: CMT (- 38.7% vs. - 22.2%, p = 0.012), HRS number in IR (- 29.2% vs. - 14.0%, p = 0.05) and full retina (- 24.7% vs. - 8.0%, p = 0.03), DRIL extension (- 62.0% vs. - 24%, p = 0.008), cysts area at DCP (- 68.7% vs. - 26.1%, p = 0.03), FAZ-CI (- 19.1% vs. - 8.3%, p = 0.02), PD at DCP (- 27.5%  vs. + 4.9%, p = 0.02). FV did not change.

CONCLUSIONS

More pronounced changes in specific inflammatory parameters in the inner retina are documented after steroid versus anti-VEGF treatment. These include reduction in HRS number, DRIL extension, CMT, cysts area at DCP. These data may help in further study of noninvasive imaging biomarkers for better evaluation of treatment response.

Cystoid macular edema related to cataract surgery and topical prostaglandin analogs: Mechanism, diagnosis, and management

Cystoid macular edema (CME) is a form of macular retina thickening that is characterized by the appearance of cystic fluid-filled intraretinal spaces. It has classically been diagnosed upon investigation after a decrease in visual acuity; however, improvements in imaging technology make it possible to noninvasively detect CME even before a clinically significant decrease in central vision. Risk factors for the development of CME include diabetic retinopathy, retinal vein occlusion, uveitis, and cataract surgery. It has been proposed that eyes with elevated intraocular pressure after cataract surgery, including those treated with prostaglandin analog eye drops, may be at higher risk for the development of CME. We summarize the current knowledge of the molecular mechanisms underlying CME, the potential role of ocular surgery and topical glaucoma medication in increasing the risk of CME, the newly developed imaging methods for diagnosing CME, and the clinical management of CME.

The expression and role of PIDD in retina after optic nerve crush

To examine the expression of P53-induced protein with a death domain (PIDD) at retina in animal model of optic nerve crush (ONC) and to investigate the role of PIDD in retinal glial activation and NF-κB activation induced by optic nerve damage, ONC animal model was established in Sprague-Dawley rats. PIDD has three isoforms (Isof); Western blot was performed to examine the expression of PIDD (Isof-1, Isof-2, and Isof-3, respectively) in retina at different time points after ONC. Retinal glial activation is closely associated with retinal neuronal death and is monitored by the expression of GFAP+ glial cells and IBA1+ microglia, then activated microglia leads to inflammatory cytokine production. NF-kB activation in glial cells also can promote neuronal death. In our study, the role of PIDD in retinal glial activation and NF-kB activation was investigated with PIDD inhibition selectively. PIDD expression (Isof-1 and Isof-3) was dramatically increased, and peaked at 3 days after ONC, while Isof-2 did not show any difference. In the ONC animal model, the number of GFAP+ glial cells and IBA1+ microglia in retinal layers was increased significantly, inflammatory cytokine production was upregulated, and NF-κB in glial cell was also activated. Moreover, those responses induced by optic nerve damage were attenuated with PIDD inhibition, which indicated that PIDD could regulate retinal glial activation, neuro-inflammation, and NF-κB activation. These results provided the direct demonstration that the PIDD (Isof-1and Isof-3) was overexpressed in retina after ONC, and PIDD may be involved in retinal neurodegenerative diseases by regulating retinal glial activation and NF-κB activation.

A Pilot Optical Coherence Tomography Angiography Study on Superficial and Deep Capillary Plexus Foveal Avascular Zone in Patients With Beta-Thalassemia Major

Purpose

To investigate foveal avascular zone (FAZ) changes in the superficial (SCP) and deep (DCP) capillary plexuses in beta-thalassemia major (BTM) patients, as shown in optical coherence tomography angiography.

Methods

Nonrandomized, comparative case series of 54 eyes of 27 BTM patients and 46 eyes of 23 healthy controls, utilizing an automated FAZ detection algorithm. Measurements included FAZ area and FAZ shape descriptors (convexity, circularity, and contour temperature). Results were compared between the two groups, and correlated to iron load and chelation therapy parameters.

Results

SCP and DCP FAZ area were not significantly different between the control and BTM groups (P = 0.778 and P = 0.408, respectively). The same was true regarding SCP FAZ convexity (P = 0.946), circularity (P = 0.838), and contour temperature (P = 0.907). In contrast, a statistically significant difference was detected between controls and BTM group regarding DCP FAZ convexity (P = 0.013), circularity (P = 0.010), and contour temperature (P = 0.014). Desferrioxamine dosage was strongly correlated to the DCP area (r = 0.650, P = 0.05) and liver magnetic resonance imaging/T2-star to DCP circularity (r = -0.492, P = 0.038). Correlations were also revealed between urine Fe excretion and DCP convexity (r = 0.531, P = 0.019), circularity (r = 0.661, P = 0.002), and contour temperature (r = -0.591, P = 0.008).

Conclusions

Retinal capillary plexuses and especially DCP seem to present unique morphologic changes in BTM patients, not in the FAZ area, but in specific shape descriptors, indicating minor but detectable FAZ changes. These changes correlate well with iron load and chelation therapy parameters. Their clinical importance and pathophysiologic implications remain to be elucidated through further studies.

Microvascular retinal changes in pre-clinical diabetic retinopathy as detected by optical coherence tomographic angiography

PURPOSE

To investigate microvascular abnormalities in diabetic patients without conventional clinical signs of diabetic retinopathy (DR).

METHODS

In this cross-sectional observational cohort study, the study group included randomly chosen participants of a community-based cohort with diabetes type 2 without DR, and the control group consisted of non-diabetic individuals from a population-based study. All participants underwent optical coherence tomographic angiography (OCTA).

RESULTS

Upon OCTA, 118 (40.4%) eyes of the study group (n = 292 eyes) showed microvascular abnormalities including foveal avascular zone erosion (95 (32.5%) eyes), non-perfusion areas in the superficial and deep retinal layers (39 (13.4%) eyes and 19 (6.5%) eyes, respectively), and microaneurysms in the superficial and deep retinal layers (22 (7.5%) eyes and 31 (10.6%) eyes, resp.). None of these abnormalities was detected in the control group (n = 80). The study group showed a lower vessel density in the superficial retinal vascular layer in all regions except for the foveal region (P < 0.001), and higher vessel density in the parafoveal region in the deep retinal vascular layer (P = 0.01). Higher diabetes prevalence was associated with lower superficial retinal vascular density (P = 0.005) in multivariable analysis. A lower radial peripapillary capillary flow density was correlated (regression coefficient r, 0.62) with higher fasting blood concentration of glucose (P < 0.001) in multivariable analysis.

CONCLUSIONS

OCTA revealed microvascular abnormalities in 40% of eyes of diabetic patients without ophthalmoscopically detectable diabetic fundus changes in a community-based population. The early stage of DR may be re-defined upon OCTA.

Quantitative Analysis of Retinal Microvascular Perfusion and Novel Biomarkers of the Treatment Response in Diabetic Macular Edema

PURPOSE

We aimed to assess the changes of retinal microvascular parameters using optical coherence tomography angiography (OCTA) between diabetes macular edema (DME) and controls. We assessed the changes between the baseline microvascular parameters and final treatment response in patients with DME, initially treated with intravitreal dexamethasone (DEX) implant followed by antivascular endothelial growth factor (VEGF) injections on an as-needed basis.

METHODS

This retrospective study included 90 DME patients and 24 healthy control subjects. All subjects had their best-corrected visual acuity (BCVA) and central macular thickness (CMT) measured at baseline and after 12 months. Vessel density (VD) in the superficial capillary plexus (SCP) and deep capillary plexus (DCP) and the deep/superficial flow ratio at baseline were analyzed. A subgroup analysis was used to compare the treatment response. A poor-response group was defined by five or more retreatments at 12 months.

RESULTS

BCVA and CMT showed a significant improvement at 12 months (all p < 0.001). The VD in the whole and parafoveal areas of the DCP was significantly reduced in DME patients compared to that in controls (all p < 0.05). The DCP/SCP flow ratio was also significantly reduced in the DME group (1.08 ± 0.03 vs. 1.05 ± 0.02, p = 0.001). In the subgroup analysis, the VD in the foveal and whole DCP areas was significantly lower in the poor-response group than that in the good-response group (p = 0.043 and p = 0.048, respectively). The DCP/SCP flow ratio was also significantly lower in the poor-response group (p = 0.011).

CONCLUSION

DME correlated with significant retinal microvascular impairment in the DCP. A decreased DCP/SCP flow ratio was observed in patients with DME that exhibited a poor treatment response. Retinal microvascular parameters could predict the treatment response in DME and help optimize clinical outcomes.

Differentiation of Underlying Pathologies of Macular Edema Using Spectral Domain Optical Coherence Tomography (SD-OCT)

Purpose: To describe the morphological characteristics of macular edema (ME) of different origins using spectral domain optical coherence tomography (SD-OCT). Methods: This article summarizes and highlights key morphologic findings, based on published articles, describing the characteristic presentations of ME of different origins using SD-OCT. The following pathologies were included: uveitic macular edema, pseudophakic cystoid macular edema (PCME), diabetic macular edema (DME), macular edema secondary to central or branch retinal vein occlusion (CRVO/BRVO), microcystic macular edema (MME), ME associated with epiretinal membrane (ERM), and retinitis pigmentosa (RP). Conclusions: Macular edema of different origins show characteristic patterns that are often indicative of the underlying cause and pathology. Thus, trained algorithms may in the future be able to automatically differentiate underlying causes and support clinical diagnosis. Knowledge of different appearances support the clinical diagnosis and can lead to improved and more targeted treatment of ME.

Association of Body Fluid Expansion With Optical Coherence Tomography Measurements in Diabetic Retinopathy and Diabetic Macular Edema

Purpose

To evaluate associations of body fluid status with optical coherence tomography measurements in patients with diabetic retinopathy (DR).

Methods

This prospective, cross-sectional study enrolled a total of 104 eyes from 104 patients with diabetes mellitus for fundus evaluations of DR and optical coherence tomography examinations. DR severity was graded via fundus photography. Systemic body fluid status was recorded via a body composition monitor with output values of total body water, extracellular water (ECW), intracellular water, and overhydration (OH). Relative overhydration (ROH) was defined as OH/ECW. Volume overload was defined as ROH ≥7%. Correlations of central subfield thickness (CST) with body fluid status were analyzed by partial correlation with adjustment for age, sex, and body mass index (BMI). Logistic regression analysis was used to evaluate factors associated with diabetic macular edema (DME).

Results

Higher levels of ECW, OH, and ROH were correlated with thick CST in patients with DR (P = 0.006, 0.021, and 0.008, respectively), but not in those without any DR (all P > 0.05), after adjusting for age, sex, and BMI. Patients with DME (n = 31) had higher OH than DR patients without DME (n = 28) or those without any DR (n = 45) (P = 0.002 and P < 0.001, respectively). Multiple regression model showed that volume overload was the independent factor for the presence of DME (odds ratio, 9.532; 95% confidence interval, 2.898-31.348; P < 0.001).

Conclusions

While both ECW and OH reflect CST in patients with DR, overhydration had particularly strong associations with DME. This study provides a novel insight into our current understanding regarding the pathogenesis for DME.

OCT Angiography Metrics Predict Progression of Diabetic Retinopathy and Development of Diabetic Macular Edema: A Prospective Study

PURPOSE

To prospectively determine the relationship of OCT angiography (OCTA) metrics to diabetic retinopathy (DR) progression and development of diabetic macular edema (DME).

DESIGN

Prospective, observational study.

PARTICIPANTS

A total of 205 eyes from 129 patients with diabetes mellitus followed up for at least 2 years.

METHODS

All participants underwent OCTA with a swept-source OCT device (DRI-OCT Triton, Topcon, Inc, Tokyo, Japan). Individual OCTA images of superficial capillary plexus (SCP) and deep capillary plexus (DCP) were generated by IMAGEnet6 (Basic License 10). After a quality check, automated measurements of foveal avascular zone (FAZ) area, FAZ circularity, vessel density (VD), and fractal dimension (FD) of both SCP and DCP were then obtained.

MAIN OUTCOME MEASURES

Progression of DR and development of DME.

RESULTS

Over a median follow-up of 27.14 months (interquartile range, 24.16-30.41 months), 28 of the 205 eyes (13.66%) developed DR progression. Of the 194 eyes without DME at baseline, 17 (8.76%) developed DME. Larger FAZ area (hazard ratio [HR], 1.829 per SD increase; 95% confidence interval [CI], 1.332-2.512), lower VD (HR, 1.908 per SD decrease; 95% CI, 1.303-2.793), and lower FD (HR, 4.464 per SD decrease; 95% CI, 1.337-14.903) of DCP were significantly associated with DR progression after adjusting for established risk factors (DR severity, glycated hemoglobin, duration of diabetes, age, and mean arterial blood pressure at baseline). Lower VD of SCP (HR, 1.789 per SD decrease; 95% CI, 1.027-4.512) was associated with DME development. Compared with the model with established risk factors alone, the addition of OCTA metrics improved the predictive discrimination of DR progression (FAZ area of DCP, C-statistics 0.723 vs. 0.677, P < 0.001; VD of DCP, C-statistics 0.727 vs. 0.677, P = 0.001; FD of DCP, C-statistics 0.738 vs. 0.677, P < 0.001) and DME development (VD of SCP, C-statistics 0.904 vs. 0.875, P = 0.036).

CONCLUSIONS

The FAZ area, VD, and FD of DCP predict DR progression, whereas VD of SCP predicts DME development. Our findings provide evidence to support that OCTA metrics improve the evaluation of risk of DR progression and DME development beyond traditional risk factors.

Subretinal pseudocysts: A novel OCT finding in diabetic macular edema

Purpose

to report the presence of a new structural optical coherence tomography (OCT) finding, namely subretinal pseudocysts, in a patient affected by diabetic retinopathy (DR).

Observations

A 52-year-old man affected by type 2 diabetes from 10 years was referred to our department complaining of a visual decline in both eyes. Best corrected visual acuity was 20/100 and 20/80 in the right and left eye, respectively. Fundus examination, fluorescein angiography, and structural OCT revealed the presence of a proliferative DR with diabetic macular edema in both eyes. Interestingly, structural OCT showed subretinal pseudocystic spaces inside the subretinal fluid of the macular neuroretinal detachment.

Conclusions and importance

Subretinal pseudocysts are a new structural OCT entity. We reported for the first time the evidence that pseudocysts may develop in the subretinal space in a case of diabetic macular edema.

Anatomical and functional changes after dexamethasone implant and ranibizumab in diabetic macular edema: a retrospective cohort study

AIM

To investigate the efficacy and safety of ranibizumab (RZB group) and dexamethasone implant (DEX group) intravitreal treatments in patients with treatment-naïve center involved diabetic macular edema (DME) by means of functional and morphological assessments.

METHODS

This retrospective cohort study included 50 eyes of 50 patients with DME treated either with RBZ or DEX. Best-corrected visual acuity (BCVA) and microperimetry were evaluated at baseline and during a 6-month follow-up. In addition, central macular thickness (CMT) by means of structural optical coherence tomography (OCT) and retinal capillary plexus density and choriocapillary density by means of OCT angiography were assessed in all cases.

RESULTS

Functional and morphological parameters significantly improved during the study period in both groups. BCVA improved significantly in both groups with a greater increase in the DEX group compared to the RBZ group (P=0.030). Microperimetry significantly differed during follow-up between the two treatments (P=0.031). In both groups CMT significantly decreased (P<0.001) without statistically significant differences between the two groups. A statistically significant increase of deep capillary plexus density was detected in both groups at 30d after therapy. The retreatment rate was 0.70±0.10 and 0.65±0.10 in the RBZ group and 0.65±0.10 and 0.50±0.11 in DEX group at 120 and 180d respectively. Two out of 25 patients in DEX group showed intraocular pressure increase requiring hypotonic eye drops.

CONCLUSION

Both treatments are very effective for DME treatment during 6mo of follow-up with a lower retreatment rate in DEX group.

Association of Optical Coherence Tomography Angiography of Collaterals in Retinal Vein Occlusion With Major Venous Outflow Through the Deep Vascular Complex

Importance

Analysis of collateral vessel formation following retinal vein occlusion may advance our understanding of the venous outflow anatomy in the macula.

Objective

To determine the location of collateral vessels with optical coherence tomography (OCT) angiography imaging.

Design, Setting, and Participants

Observational retrospective cohort study. Collateral vessel formation was studied with OCT angiography (OCTA) in patients with retinal vein occlusion (RVO). The study took place at 2 retinal practices (Vitreous Retina Macula Consultants of New York and Stein Eye Institute, University of California, Los Angeles), with patient records retrieved from March 2015 to August 2017. Data analysis was completed in November 2017.

Exposures

Collaterals identified with fundus photography and/or fluorescein angiography were analyzed with OCTA to determine their course through the superficial vascular plexus (SVP) and the deep vascular complex (DVC).

Main Outcomes and Measures

Collateral vessel pathways through the SVP and DVC were analyzed with cross-sectional and en face OCT and OCTA segmentation and color-coded volume renderings prepared from raw OCTA voxel data.

Results

From 23 eyes (22 branch and 1 hemispheric retinal vein occlusion ) of 23 patients (mean [SD] age, 73 [11] years), 101 collateral vessels were identified and analyzed (mean [SD], 4.4 [2.0]; range, 2-9 collateral per eye). On OCTA, the collaterals appeared as curvilinear dilated flow signals that connected veins across the horizontal raphe or veins on opposite sides of an occluded venous segment within the same retinal hemisphere. Of the 101 collaterals analyzed, all showed greater flow signal in the DVC, and all had some portion of their course identified within the DVC. No collaterals were found exclusively in the SVP. Volume renderings for 3 cases confirmed qualitatively that retinal collateral vessels course through the retina predominantly at the level of the DVC.

Conclusions and Relevance

Based on a limited number of cases, all collateral vessels associated with retinal vein occlusion were found to course through the DVC. The absence of collaterals isolated to the SVP supports a serial arrangement of the SVP and DVC, with venous drainage predominantly coursing through the DVC.

Retinal inner nuclear layer volume reflects inflammatory disease activity in multiple sclerosis; a longitudinal OCT study

Background

The association of peripapillary retinal nerve fibre layer (pRNFL) and ganglion cell-inner plexiform layer (GCIPL) thickness with neurodegeneration in multiple sclerosis (MS) is well established. The relationship of the adjoining inner nuclear layer (INL) with inflammatory disease activity is less well understood.

Objective

The objective of this paper is to investigate the relationship of INL volume changes with inflammatory disease activity in MS.

Methods In this longitudinal, multi-centre study, optical coherence tomography (OCT) and clinical data (disability status, relapses and MS optic neuritis (MSON)) were collected in 785 patients with MS (68.3% female) and 92 healthy controls (63.4% female) from 11 MS centres between 2010 and 2017 and pooled retrospectively. Data on pRNFL, GCIPL and INL were obtained at each centre.

Results

There was a significant increase in INL volume in eyes with new MSON during the study (N = 61/1562, β = 0.01 mm³, p < .001). Clinical relapses (other than MSON) were significantly associated with increased INL volume (β = 0.005, p = .025). INL volume was independent of disease progression (β = 0.002 mm³, p = .474).

Conclusion

Our data demonstrate that an increase in INL volume is associated with MSON and the occurrence of clinical relapses. Therefore, INL volume changes may be useful as an outcome marker for inflammatory disease activity in MSON and MS treatment trials.

Comparison of Retinal Layer Thickness and Vascular Density between Acute and Chronic Branch Retinal Vein Occlusion

Purpose

To compare retinal layer thickness and chorioretinal vascular density (VD) between acute and chronic branch retinal vein occlusion (BRVO).

Methods

This study included patients with BRVO. The VD of the superficial capillary plexus (VDs), the VD of the deep capillary plexus (VDd), and VD of the choriocapillaris were obtained using optical coherence tomography angiography. Acute and chronic BRVO data were compared to assess differences between the involved and uninvolved areas.

Results

We included 17 eyes with acute BRVO and 23 eyes with chronic BRVO. The VDs in the involved area were not significantly different between the involved area and in the uninvolved area in acute BRVO (p = 0.551). However, the difference was significant in chronic BRVO (p = 0.013). The VDd in the involved area was lower than in the uninvolved area in both acute and chronic BRVO (p = 0.020, p = 0.003, respectively). In addition, the VD of the choriocapillaris values did not differ significantly between acute and chronic BRVO, or between involved and uninvolved areas. The VDs in the involved area in chronic BRVO were lower than in acute BRVO (p = 0.047), and the VDd did not differ between acute and chronic BRVO in all areas.

Conclusions

Vascular impaired patterns in the retinal layer differed between acute and chronic BRVO. These results may suggest that vascular change and remodeling develops differently in acute and chronic phases in BRVO.

Insights into the pathogenesis of cystoid macular edema: leukostasis and related cytokines

Cystoid macular edema (CME) is the abnormal collection of intraretinal fluid in the macular region, especially in the inner nuclear and outer plexiform layers. CME leads to severe visual impairment in patients with various retinal diseases, such as diabetic retinopathy, retinal vascular occlusion, choroidal neovascularization, and uveitis. Although various retinal conditions lead to CME, a shared pathogenesis of CME is involved in these diseases. Accordingly, the pathogenesis of CME based on vasogenic mechanisms is first discussed in this review, including vascular hyperpermeability, leukostasis, and inflammation. We then describe cytotoxic mechanisms based on retinal Müller cell dysfunction. This comprehensive review will provide an understanding of the pathogenesis of CME for potential therapeutic strategies.

Grading of macular perfusion in retinal vein occlusion using en-face swept-source optical coherence tomography angiography: a retrospective observational case series

Background

To evaluate the efficacy of swept –source optical coherence tomography angiography (SS-OCTA) in grading macular perfusion in retinal vein occlusion.

Methods

Retrospective observational case series including patients with different types of retinal vein occlusion (RVO). SS-OCTA utilizes OCTARA algorithm to examine the retinal vascular plexuses for the presence of morphological signs of ischemia according to a predetermined grading scheme. The findings were compared with fundus fluorescein angiography (FFA), and swept-source optical coherence tomography (SS-OCT) features. Bivariate correlation, coefficient of determination, and crosstabs procedures were used to calculate inter-variable linear correlation, relative contribution of the tested variables, and multivariate association, respectively.

Results

The study included 144 eyes of 138 patients. The most common type of RVO was branch retinal vein occlusion (BRVO) (53%). The superficial capillary plexus (SCP) and the deep capillary plexus (DCP) did not correlate with each other in all parameters tested. Increased central macular thickness (CMT) and disrupted retinal outer layers (DROL) were associated with increased severity of ischemia in DCP. Disorganized retinal inner layers (DRIL) correlated significantly with the presence of perifoveal capillary ischemia in the SCP and the DCP. Macular ischemia on FFA correlated with ischemia in the SCP layer only. Increased CMT, DROL and DRIL on SS-OCT, and SCP and DCP ischemia on SS-OCTA contributed significantly to diminished best-corrected visual acuity (BCVA).

Conclusion

SS-OCTA is more precise in defining the extent and location of maximum ischemic insult following RVO compared to FFA, hence represents a more efficient grader for ischemic damage in the posterior pole. Increased CMT, DRIL, and DROL on SS-OCT, and SCP and DCP ischemia on SS-OCTA are significant predictors of poor visual outcome.

ACUTE PSEUDOPHAKIC CYSTOID MACULAR EDEMA IMAGED BY OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

PURPOSE

To study macular capillary changes and vessel density in acute pseudophakic cystoid macular edema (PCME) before and after treatment using optical coherence tomography angiography.

METHODS

Retrospective observational case-control study of seven consecutive patients (eight eyes) with PCME and eight age-matched control eyes imaged with optical coherence tomography angiography (RTVue XR Avanti; Optovue, Inc, Fremont, CA) using Projection Removal Artifacts software. Vessel density was calculated.

RESULTS

The mean time to diagnosis of PCME was 2.3 ± 0.9 months after surgery. At initial examination, the superficial capillary plexus pattern was near-normal in all PCME eyes, although it was attenuated in the deep capillary plexus. The mean vessel density of the superficial capillary plexus in PCME eyes was slightly but significantly lower than in control eyes (47.8 ± 3.8% vs. 52.9 ± 4.0%, P = 0.01), the difference being greater in the deep capillary plexus (44.1 ± 7.4% vs. 54.2 ± 3.2%, P = 0.007). After resolution of the edema, the deep capillary plexus completely recovered its normal pattern and the vessel density in both plexuses was no longer different from that observed in control eyes.

CONCLUSION

Macular vessel density after resolution of an acute PCME did not differ from that of normal control eyes in both the superficial capillary plexus and deep capillary plexus, unlike macular edema in retinal vaso-occlusive diseases.

Taxane Induced Cystoid Macular Edema: Case Report and Integrated Pathogenic Theory

PURPOSE

To report a case of a 73-year-old man who presented with decreased visual acuity due to bilateral macular edema after paclitaxel administration for prostate cancer.

METHODS

The ophthalmic evaluation consisted of medical and ocular history, Best Corrected Visual Acuity, slit-lamp biomicroscopy and Spectral-domain optical coherence tomography / Fluorescein Angiography.

RESULTS

Optical Coherence Tomography and Fluorescein Angiography revealed silent cystoid macular edema. After consulting with the oncologist, the cessation of paclitaxel therapy was decided. The patient presented a gradual but steady resumption of the retinal edema, with complete restoration of normal retinal morphology and function within two months. The pathogenesis of the silent Cystoid Macular Edema (CME) is still unclear. Based on our case and a critical review of the previous observations and published data, we propose that the underlying cause of Taxane induced CME is the functional failure of Aquaporin mediated water transport at the level of retinal Intermediate and Deep capillary plexuses, and at lesser extent at the level of the Retinal Pigment Epithelium.

CONCLUSION

Taxane induced silent CME should be attributed to the action of Taxanes on the microtubule guided aquaporin vesicles transport to the cell membrane. In our case of Taxane induced silent CME, withdrawal of the taxane was enough for complete recovery, and no additional treatment was needed.

Subretinal pseudocyst: A novel optical coherence tomography finding in age-related macular degeneration

Purpose:

To report the presence of a new structural optical coherence tomography finding, namely, subretinal pseudocysts, in a patient affected by age-related macular degeneration.

Methods:

Case report including multimodal imaging discussion.

Case Report:

We report a case of a 77-year-old woman affected by age-related macular degeneration from 7 years. Best corrected visual acuity was counting fingers and 20/40 in the right and left eye, respectively. The left eye was affected by type 1 macular neovascularization treated by 34 intravitreal injections of anti-vascular endothelial growth factor (22 ranibizumab and 12 aflibercept injections). Interestingly, structural optical coherence tomography showed the persistence of a subretinal cystoid space (i.e. ‘subretinal pseudocyst’) after the last anti-vascular endothelial growth factor treatment, even in absence of other signs of exudation.

Conclusions:

Subretinal pseudocysts are a new structural optical coherence tomography entity. We reported for the first time the evidence that pseudocysts may develop in the subretinal space in a case of age-related macular degeneration.

Three-Dimensional Microscopy Demonstrates Series and Parallel Organization of Human Peripapillary Capillary Plexuses

Purpose

To define the three-dimensional topologic organization of the human peripapillary capillary plexuses in order to better understand the hemodynamic characteristics of this retinal circulation.

Methods

The retinal microvasculature was perfusion labeled in five normal human donor eyes, and optical stacks were collected from regions immediately superior, temporal, inferior, and nasal to the optic disk by using confocal scanning laser microscopy. The spatial location and morphometric characteristics of capillary plexuses were compared. Three-dimensional visualization strategies were used to document the organization of vascular conduits that interconnect capillary beds and to study the communications between capillary beds and precapillary arterioles and postcapillary venules.

Results

The peripapillary microcirculation is composed of four capillary plexuses, including the radial peripapillary capillary plexus at the level of the nerve fiber layer, the superficial capillary plexus (SCP) at the level of the ganglion cell layer, the intermediate capillary plexus located at the inner boundary of the inner nuclear layer, and the deep capillary plexus located at the outer boundary of the inner nuclear layer. Capillary diameter and density were significantly different between the four plexuses (both P ≤ 0.011). The SCP is the only capillary bed that receives feeding and draining branches directly from precapillary arterioles and postcapillary venules, respectively. Four different inflow and outflow patterns characterized the communication between the SCP and surrounding capillary beds.

Conclusions

The capillary plexuses of the human peripapillary microcirculation are arranged in series and parallel and manifest specializations that likely reflect the unique metabolic demands and biochemical environment of the retinal layers.

Collateral Vessels in Branch Retinal Vein Occlusion: Anatomic and Functional Analyses by OCT Angiography

PURPOSE

To analyze collateral vessels (CVs) associated with branch retinal vein occlusion (BRVO) anatomically and functionally using OCT angiography (OCTA).

DESIGN

Retrospective review.

PARTICIPANTS

Twenty-nine consecutive patients with BRVO.

METHODS

The distribution of the CVs 12 months after the onset of BRVO was studied using spectral-domain OCTA. En face 3 × 3-mm OCTA images were acquired from 9 locations centered on the fovea and used to create a montage image of an 8.1 × 8.1-mm square. The CVs were identified in 3 separate areas: the radial peripapillary capillary (RPC), superficial capillary plexus (SCP), and deep capillary plexus (DCP) layers. The numbers of CVs were evaluated in 4 regions: zone 1, the area within a 3-mm diameter circle centered on the fovea; zone 2, the area between the 3-mm diameter circle and its outer 6-mm diameter circle; zone 3, the area beyond the 6-mm diameter circle; and the temporal raphe.

MAIN OUTCOME MEASURES

The relationship between the number of CVs and vessel density (VD) in each layer, persistent macular edema (ME) at 12 months, and the number of injections of anti-vascular endothelial growth factor (VEGF) agents.

RESULTS

The number of CVs in zone 1 was correlated negatively (P = 0.0079) with the VD in the SCP, and the numbers of CVs in zone 3 and the temporal raphe were correlated negatively (P = 0.0017 and P = 0.036, respectively) with the VD in the DCP. The number of CVs in the RPC and total number of CVs were also correlated negatively (P = 0.0034 and P = 0.0113, respectively) with the VD in the DCP. In patients with persistent ME, the number of CVs in zone 1 was significantly (P = 0.0156) greater than in patients with nonpersistent ME and correlated positively (P = 0.025) with the number of anti-VEGF injections.

CONCLUSIONS

The CVs in BRVO form as result of capillary dropout and are considered to represent remodeling of the retinal capillaries. The CVs around the fovea may be good indicators of persistent ME.

Caffeic acid phenethyl ester attenuates nuclear factor‑κB‑mediated inflammatory responses in Müller cells and protects against retinal ganglion cell death

Glaucoma is characterized by the death of retinal ganglion cells (RGCs) and visual field defects, and is a leading cause of blindness worldwide. Caffeic acid phenethyl ester (CAPE), a natural polyphenolic found in propolis from honeybee hives, can inhibit the activation of nuclear factor κ light-chain-enhancer of activated B cells (NF-κB) and has therapeutic potential in inflammatory disease. The present study used a rat model of optic nerve crush (ONC) injury to investigate the effect of CAPE on glaucoma. The death of RGCs at day 14 was significantly reduced in CAPE-treated animals compared with the non-treated group according to Brn3a and TUNEL staining. In addition, CAPE decreased the severity of inflammation in the retina, reflected by the decreased expression of inflammatory cytokines, including interleukin (IL)-8, IL-6, inducible nitric oxide synthase, cycloooxygenase-2, tumor necrosis factor-α and chemokine C-C ligand-2, in CAPE-treated rats. The hypertrophy of astrocytes and Müller cells (gliosis) caused by ONC was also found to be attenuated by CAPE, accompanied by the inhibition of NF-κB signaling. Similarly, in vitro, CAPE suppressed the proliferation and migration of primary astrocytes induced by lipopolysaccharide, as well as the activation of NF-κB. These results suggest that CAPE protected against RGC and attenuated inflammatory responses in a rat model of ONC by suppressing NF-κB activation.

Resveratrol Delays Retinal Ganglion Cell Loss and Attenuates Gliosis-Related Inflammation From Ischemia-Reperfusion Injury

Purpose

Resveratrol has been shown to enhance the survival of retinal ganglion cells (RGCs) following ischemia-reperfusion (I/R) injury for glaucoma. However, the precise mechanisms for resveratrol's protective effects are still unclear. The aim of this study is to determine whether resveratrol can inhibit RGC apoptosis, retinal gliosis, and inflammation, all of which are critical events in retinal degeneration following I/R injury.

Methods

Right retinal ischemia was induced in adult male Sprague Dawley rats by increasing intraocular pressure to 110 mm Hg for 60 minutes, and the left eyes maintained at normal pressure serve as the control. Intraperitoneal injection of resveratrol or control buffer was performed continuously for 3 days from pre- to post-I/R injury and the protective effects were evaluated and compared. RGCs were retrogradely labeled with Fluoro-Gold by injection into superior colliculi. Apoptosis was detected by TUNEL staining. Western blotting and immunostaining for Bax, Bcl-2, and Caspase-3 were used to explore the Bax-associated apoptotic pathway. Gliosis was assessed by western blotting and immunostaining of retinal cross sections with anti-glial fibrillary acidic protein (GFAP) antibodies.

Results

In this study, resveratrol treatment significantly reduced retinal damage and RGC loss as demonstrated by the relatively intact tissue structure in hematoxylin and eosin staining at day 7 and increased Fluoro-Gold labeling of RGCs at day 14, respectively. We found that resveratrol exhibited an anti-apoptotic effect as assessed by reduced TUNEL staining, inhibition of the early upregulated expression of the apoptosis-related protein Bax, and decreased subsequently cleaved caspase-3. However, it did not affect Bcl-2 levels. Moreover, in our I/R injury model, the combined response of reactive gliosis and related inflammation, which were demonstrated by an early induction of pro-inflammatory mediators and subsequently increased GFAP level, were significantly attenuated after resveratrol treatment.

Conclusions

These results demonstrate that resveratrol can prevent RGC death by blocking the Bax-caspase-3-dependent apoptotic pathway and suppressed gliosis-related inflammation in the retina after I/R injury. Together these results support the use of resveratrol as a possible therapeutic strategy for glaucoma.

Current and Future Pharmacologic Therapies for Diabetic Retinopathy

Background:

Currently, diabetic retinopathy is the leading cause of permanent visual loss in workingage adults in industrialized nations. The chronic microangiopathic changes associated with diabetic retinopathy lead to the most common causes of severe permanent visual loss: diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR). Multiple studies have evaluated different pharmacotherapies for different levels of retinopathy.

Methods:

A review of the pathophysiology of diabetic retinopathy and current and emerging pharmacotherapies for diabetic retinopathy.

Results:

Historically, DME has been the primary focus of treatment in patients with nonproliferative diabetic retinopathy (NPDR). Due to the rapidly increasing number of agents and treatment options, management algorithms for DME have become increasingly complex. Furthermore, spectral domain optical coherence tomography (OCT) has allowed unparalleled sensitivity and specificity for detecting macular edema. All available intravitreal vascular endothelial growth factor (VEGF) inhibitors have demonstrated efficacy in the treatment of patients with DME and PDR. Intravitreal triamcinolone acetonide has also proven beneficial in diabetic retinopathy. Most recently, various corticosteroids have been designed as sustained-release intraocular implants in order to reduce the burden and risks associated with retreatment. Current research is focused on providing new agents that target alternate pathways and signaling molecules to provide patients with additional therapeutic tools, especially in patients who have an incomplete response to the current medications.

Conclusion:

Anti-VEGF therapy has revolutionized the medical management of diabetic retinopathy. The most important existing challenges in the treatment of diabetic retinopathy are improving visual outcomes and decreasing the treatment burden associated with repeated intravitreal injections. Combination therapy with anti-VEGF and corticosteroids with other previously available treatments, such as panretinal photocoagulation, may be a reasonable clinical strategy to reduce the intravitreal injections burden. Many exciting novel drugs that target newly discovered pathways hold clinical promise. The results of ongoing randomized clinical trials will answer the important concerns surrounding new drugs and delivery devices: safety and visual outcomes.

Role of Inflammation in Classification of Diabetic Macular Edema by Optical Coherence Tomography

Diabetic macular edema (DME) is the abnormal accumulation of fluid in the subretinal or intraretinal spaces in the macula in patients with diabetic retinopathy and leads to severely impaired central vision. Technical developments in retinal imaging systems have led to many advances in the study of DME. In particular, optical coherence tomography (OCT) can provide longitudinal and microstructural analysis of the macula. A comprehensive review was provided regarding the role of inflammation using OCT-based classification of DME and current and ongoing therapeutic approaches. In this review, we first describe the pathogenesis of DME, then discuss the classification of DME based on OCT findings and the association of different types of DME with inflammation, and finally describe current and ongoing therapeutic approaches using OCT-based classification of DME. Inflammation has an important role in the pathogenesis of DME, but its role appears to differ among the DME phenotypes, as determined by OCT. It is important to determine how the different DME subtypes respond to intravitreal injections of steroids, antivascular endothelial growth factor agents, and other drugs to improve prognosis and responsiveness to treatment.