Cytosolic glutaredoxin 1 is upregulated in AMD and controls retinal pigment epithelial cells proliferation via ß-catenin.

Thioredoxin (Trx) family proteins are key players in redox signaling. Here, we have analyzed glutaredoxin (Grx) 1 and Grx2 in age-related macular degeneration (AMD) and in retinal pigment epithelial (ARPE-19) cells. We hypothesized that these redoxins regulate cellular functions and signaling circuits such as cell proliferation, Wnt signaling and VEGF release that have been correlated to the pathophysiology of AMD. ARPE-19 cells were transfected with specific siRNAs to silence the expression of Grx1 and Grx2 and were analyzed for proliferation/viability, migration capacity, ß-catenin activation, and VEGF release. An active site-mutated C-X-X-S Grx1 was utilized to trap interacting proteins present in ARPE-19 cell extracts. In both, AMD retinas and in ARPE-19 cells incubated under hypoxia/reoxygenation conditions, Grx1 showed an increased nuclear localization. Grx1-silenced ARPE-19 cells showed a significantly reduced proliferation and migration rate. Our trapping approach showed that Grx1 interacts with ß-catenin in a dithiol-disulfide exchange reaction. Knock-down of Grx1 led to a reduction in both total and active ß-catenin levels. These findings add redox control to the regulatory mechanisms of ß-catenin signaling in the retinal pigment epithelium and open the door to novel therapeutic approaches in AMD that is currently treated with VEGF-inhibitors.

Application of subretinal fluid to close refractory full thickness macular holes: treatment strategies and primary outcome: APOSTEL study.

INTRODUCTION: Persisting macular holes (PMH) after surgical release of any epiretinal traction of the vitreous and adjacent membrane may rely on secondary firm adhesions between the retracted retina and adjacent retinal pigment epithelium. Secondary application of subretinal (SR)-fluid may release these adhesions followed by an anatomical closure. METHODS: Twelve surgeons applied in a consecutive case series SR-fluid in 41 eyes with PMH and reported retrospectively their initial surgical, anatomical and functional experience with this approach. RESULTS: The mean duration of the MH prior to SR-fluid application was 17 months (6-96 months). The mean age of the patients at the time of surgery was 72 years (54-88). The mean preoperative aperture diameter of the opening was 1212 µm (239-4344 µm), base diameter 649 µm (SD 320 µm). The mean preoperative BCVA prior to surgery was 0.1 (0.01-0.3). All patients (41/41) complained about reduced BCVA and a significant central scotoma (negative scotoma) in their central field of vision. The secondary closure rate for our PMH was 85.36% (35 out of 41 eyes) at 6 weeks after surgery. The postoperative BCVA improved to 0.22 (0.02-0.5). The application of SR-fluid was not associated with major intraoperative adverse effects. CONCLUSION: Remaining SR-adhesions may inhibit PMH closure. Their release by application of SR-fluid will lead to a fast and immediate anatomical closure in many cases without serious adverse events.

Ocriplasmin treatment for vitreomacular traction in real life: can the indication spectrum be expanded?

PURPOSE: To evaluate the efficacy of intravitreal ocriplasmin for the resolution of vitreomacular traction (VMT) with or without a full thickness macular hole (FTMH) in the clinical setting and to assess whether the indication spectrum of this treatment modality can be expanded beyond that of the MIVI-TRUST trials. METHODS: The records of patients with VMT with or without FTMH, who were treated with intravitreal ocriplasmin were reviewed. Patients were divided in two groups. In the first group, VMT with or without FTMH was present without any other macular pathology. In the second group, VMT with or without FTMH occurred alongside of other macular disease including age-related macular degeneration, diabetic maculopathy and post-operative pseudophakic cystoid macular edema. RESULTS: Release of the VMT was achieved in 12/20 patients (12/20 eyes) of the first group. 16 eyes in this group met 3 or more criteria known to be associated with favorable prognosis after intravitreal ocriplasmin treatment. No cases of release of the VMT were observed in the second group, which included 15 patients (15 eyes). Significant improvement of visual acuity and reduction of the central macular thickness was observed only in the subgroup of eyes which responded to treatment. CONCLUSIONS: Concomitant macular pathology was a significant factor for treatment failure and we suggest that ocriplasmin should be regarded with caution in these cases. Careful patient selection for treatment with ocriplasmin using specific criteria in the clinical setting can provide superior results to those reported in the MIVI-TRUST trials.

The predictability of ocriplasmin treatment effects: is there consensus among retinal experts? Results from the EXPORT study.

PURPOSE: To evaluate the agreement and predictability of ocriplasmin treatment effects among retinal experts (raters) by assessment of retinal imaging data of eyes treated for vitreomacular traction in nine different centers in Germany and Austria. METHODS: Retrospective cohort study. Combined confocal near-infrared scanning laser ophthalmoscopy and spectral-domain optical coherence tomography images (Spectralis® device, Heidelberg Engineering GmbH, Germany) from 136 eyes of 135 subjects were reviewed by 14 raters using an internet-based grading database and a standardized questionnaire. In addition to the images taken within 2 days prior to treatment, age, gender, and lens status were disclosed to the raters. Treatment success was defined as a complete cleavage of the posterior vitreous cortex at day 28±5. Main outcome was the agreement and predictability among raters for assessment of treatment success. RESULTS: Raters generally accepted starting ocriplasmin treatment (chance for treatment success ≥ 1%) in 22.4 to 69.1% (median 53.2%) of eyes (moderate intra- and interrater agreements with kappa-values of 0.6 and 0.48). The likelihood for a high potential treatment success (equal or higher than 25%) was judged by the raters in 43.4% to 86.0% (median 62.6%) of eyes (moderate intra- and fair interrater agreements with kappa-values of 0.56 and 0.22). Allocating eyes for high potential treatment success overall increased the odds by 3.07, with odds ratios of single raters up to 4.06 to 6.16. CONCLUSIONS: These results underscore the importance of training health care providers in the evaluation of retinal imaging data and also to define characteristic morphological features better in the presence of vitreoretinal interface diseases. The better results of single raters in the predictability of treatment success by the allocation of eyes in the high-potential group indicates the high relevance of the meticulous analysis of retinal images.

VITRECTOMY FOR PERSISTENT MACULAR HOLES FOLLOWING OCRIPLASMIN INJECTION: A Comparative Multicenter Study.

PURPOSE: To determine functional and anatomical outcomes of pars plana vitrectomy for persistent full-thickness macular hole (MH) after intravitreal injection of ocriplasmin. METHODS: This is a multicenter retrospective interventional study of 37 eyes of 37 patients who underwent pars plana vitrectomy with internal limiting membrane peeling for persistent MH after ocriplasmin treatment between December 2013 and December 2015 and comparison with 35 eyes of 35 patients who were offered ocriplasmin injection but underwent pars plana vitrectomy alone without pharmacologic vitreolysis before surgery. In addition, 24 matched pairs (MH diameter at baseline ±5 µm) were analyzed. Clinical data such as visual acuity, intraoperative characteristics, and spectral domain optical coherence tomography images were reviewed. Main outcome measures were visual acuity and MH closure rate. RESULTS: After a mean follow-up period of 9 months, postoperative mean visual acuity showed no significant differences between ocriplasmin-treated eyes (logarithm of minimum angle of resolution 0.37 ± 0.26, Snellen 20/47) and eyes without ocriplasmin treatment (logarithm of minimum angle of resolution 0.39 ± 0.25; Snellen 20/49) (P > 0.9). After ocriplasmin injection, mean MH diameter enlarged from 217 ± 102 µm to 384 ± 239 µm (P < 0.001). Matched-pair analysis revealed no difference in gain of visual acuity between the first visit and the last follow-up (P = 0.29). Macular hole closure was observed in similar proportion in ocriplasmin-treated eyes (97%) and vitrectomy-only eyes (94%) (P > 0.5). CONLCUSION: Eyes with persistent MH after ocriplasmin injection showed significant visual improvement after pars plana vitrectomy. Matched-pair analysis revealed no statistical differences in functional and anatomical postoperative results comparing with eyes of similar MH diameter that proceeded directly to surgery without ocriplasmin pretreatment.

IMPACT OF VITREORETINAL INTERFACE ARCHITECTURE ON SUCCESSFUL VITREOMACULAR TRACTION RESOLUTION IN EYES SCHEDULED FOR INTRAVITREAL OCRIPLASMIN THERAPY.

PURPOSE: To evaluate the impact of the vitreoretinal interface architecture, in specific the angle between the posterior vitreous cortex and the internal limiting membrane, on vitreomacular traction (VMT) resolution in eyes treated with intravitreally injected ocriplasmin (Jetrea). METHODS: Retrospective, multicenter cohort study and exploratory data analysis. Spectral domain optical coherence tomography assessments were performed before scheduled ocriplasmin injections. General (age and sex) as well as ocular variables (lens status, presence of epiretinal membrane formations, horizontal diameter of VMT, central retinal thickness, and in particular various prespecified angles between the posterior vitreous cortex and internal limiting membrane) were analyzed to evaluate their impact on successful VMT resolution. RESULTS: Fifty-nine eyes of 59 patients were included. Univariate analysis of age (odds ratio [OR]: 0.881; 95% CI: [0.812-0.955]; P = 0.0022) and lens status (OR: 11.03; 95% CI: [2.23-54.57]; P = 0.0033) had a significant impact on successful VMT resolution, whereas sex (OR: 0.668; 95% CI: [0.126-2.065]; P = 0.4906), epiretinal membrane formation (OR: 0.581; 95% CI: [0.168-2.006]; P = 0.3903), horizontal diameter of VMT (OR: 0.99930; 95% CI: [0.99825-1.00035]; P = 0.1886), and central retinal thickness (OR: 0.9985; 95% CI: [0.9934-1.00436]; P = 0.56) failed. The angle at 500 µm apart from the fovea centralis, irrespective if measured nasally (OR: 1.135; 95% CI: [1.013-1.272]; P = 0.0289) or temporally (OR: 1.099; 95% CI: [1.001-1.208]; P = 0.0485), showed a significant correlation with VMT resolution. CONCLUSION: The angle between the posterior vitreous cortex and the internal limiting membrane 500 µm apart from the fovea centralis correlates with VMT resolution and may be a clinically useful marker for selection of patients to be treated with ocriplasmin. This observation needs to be proven in a prospective confirmatory investigation.

Outcome of intravitreal dexamethasone implant for the treatment of ranibizumab-resistant macular edema secondary to retinal vein occlusion.

To assess the effect of intravitreal dexamethasone implant (Ozurdex) for the treatment of macular edema secondary to retinal vein occlusion (RVO) resistant to repeated intravitreal ranibizumab injection. Retrospective review of 11 patients (11 eyes) with ranibizumab-resistant macular edema secondary to RVO. Macular edema was considered refractory to ranibizumab if no change of the pattern of macular fluid on optical coherence tomography and no change of best-corrected visual acuity (BCVA) was observed after at least three consecutive monthly injections, excluding the loading dose. A single Ozurdex injection was performed and BCVA and central foveal thickness (CFT) were reviewed 2, 3, and 6 months after treatment. Mean BCVA improved significantly from 0.51 logarithm of the minimal angle of resolution (log MAR) at baseline to 0.3 log MAR (p = 0.03) at 2 months and 0.29 log MAR (p = 0.003) at 3 months. There was no significant difference in the BCVA between baseline at 6 months (p = 0.62). Mean CFT reduced significantly from 538 µm at baseline to 281 µm at 2 months (p = 0.00003), 281 µm at 3 months (p = 0.00003), and 445 µm at 6 months (p = 0.03). Treatment with Ozurdex results in improvement of BCVA and reduction of CFT in patients with ranibizumab refractory macular edema due to RVO at 3 months. However, it seems that the visual acuity gain may not last up to 6 months, so that a re-injection before this time point could be considered.

20 g PPV with indocyanine green-assisted ILM peeling versus 23 g PPV with brilliant blue G-assisted ILM peeling for epiretinal membrane.

To compare the anatomical and visual outcomes of 20 gauge (g) pars plana vitrectomy (PPV) with indocyanine green (ICG)-assisted internal limiting membrane (ILM) peeling and 23 g PPV with brilliant blue G (BBG)-assisted ILM peeling for idiopathic epiretinal membrane (ERM). 38 eyes of 38 patients with idiopathic ERM were included. They were divided in two groups: group 1 (18 eyes) underwent 20 g PPV with ICG-assisted ILM peeling and group 2 (20 eyes) 23 g PPV with BBG-assisted ILM peeling. Postoperative best-corrected visual acuity (BCVA) and central macular thickness (CMT) were compared. Average BCVA in group 1 improved significantly from 0.60 logarithm of the minimal angle of resolution (log MAR) at baseline to 0.3 log MAR postoperatively. Average BCVA in group 2 improved significantly from 0.60 log MAR at baseline to 0.3 log MAR postoperatively. Mean CMT reduced significantly from 473 to 375 µm in group 1 and from 486 to 396 µm in group 2. There were no significant differences in the BCVA and CMT between the groups. Both surgical methods appeared to be safe and provided similar anatomical and visual outcomes.

Intravitreal vascular endothelial growth factor.

PURPOSE: To evaluate whether a specific pre-analytical stabilization regimen is needed for naïve vitreous taps to detect true values of intrinsic VEGF levels. METHODS: Fourteen consecutive patients with different vitreomacular pathologies without blood-retina-barrier breakdown were scheduled for standard 23-gauge three-port pars plana vitrectomy, and naïve vitreous taps were sampled at the beginning of each procedure. The extracted vitreous specimen was split; one half was immediately stored in a -20 °C freezer (unstabilized samples) and the other half was instantly stabilized with albumin (2.5 % final conc.), followed by arginine stabilization (1.25 M final conc.) and consecutively stored in a -20 °C freezer (stabilized samples). RESULTS: Intravitreal VEGF was detected in all 14 analyzed samples (100 %). VEGF levels were shown to be 46.5 pg/ml ± 62.3 pg/ml (MV ± SD; range: 5.99-232.3 pg/ml) in unstabilized, and 120.4 pg/ml ± 94.4 pg/ml (range: 42.9 pg/ml-289.6 pg/ml) in stabilized vitreous samples. Intravitreal VEGF levels in stabilized vitreous samples were on average 2.6-fold, and thus significantly higher than in unstabilized taps of same eyes (p = 0.001, Wilcoxon test). VEGF levels in stabilized vitreous samples can be up to 8.5 times higher than in corresponding unstabilized vitreous taps of same eyes (bootstrap analysis). Intravitreal VEGF levels in unstabilized samples correlate with those in stabilized vitreous taps (r = 0.594; p = 0.025; Pearson). CONCLUSIONS: An adequate pre-analytic stabilization regimen is needed to evaluate the most accurate intravitreal VEGF levels. This in turn will result in a better understanding of the physiological as well as pathological role of VEGF within the eye. Furthermore, knowing the true value of intravitreal VEGF levels will help to calculate the dosage of intravitrealy applied anti-VEGF drugs.

Intravitreal functional plasminogen in eyes with branch retinal vein occlusion.

PURPOSE: To evaluate whether intravitreal functional plasminogen is elevated in eyes with branch retinal vein occlusion (BRVO) and to discover whether intravitreal plasminogen activities are correlated with the extent of blood-retina barrier (BRB) breakdown. METHODS: Our study is a prospective case series of 20 consecutive patients with BRVO and 10 consecutive patients serving as controls. Vitreous taps were extracted from the central vitreous body and plasminogen was functionally determined in an innovative, ultrasensitive p-nitroanilide reaction after activation with streptokinase (100% of normal, %N = functional plasminogen in pooled normal citrated plasma). Intravitreal VEGF levels were assayed to estimate BRB breakdown. RESULTS: Intravitreal functional plasminogen was detected in all analyzed samples (n = 30) and mean (±SD) plasminogen activities were found to be 0.97 ± 1.06%N (range: 0.03-3.9%N). Patients suffering from BRVO exhibited significantly higher intravitreal plasminogen (1.35 ± 1.11%N) in comparison with controls (0.20 ± 0.21%N, p < 0.001). Intravitreal VEGF concentrations in the BRVO group (576 ± 547 pg/ml) were significantly higher than these in controls (111 ± 120 pg/ml, p = 0.003). There was a significant correlation between intravitreal functional plasminogen and intravitreal VEGF levels (r = 0.519, p = 0.003). CONCLUSIONS: Intravitreal functional plasminogen is significantly elevated in eyes suffering from BRVO and correlates with the extent of BRB breakdown. The induction of posterior vitreous detachment by using intravitreally administered recombinant tissue plasminogen activator (enzymatic vitreolysis) should be explored in further investigations.

Intracameral concentrations of the fibrinolytic system components in patients with age-related macular degeneration.

PURPOSE: To detect the intracameral concentrations and activities of plasminogen and other components of the fibrinolytic system, and to investigate whether those concentrations and activities are higher in patients with age-related macular degeneration (AMD) in comparison to healthy controls. METHODS: Prospective case series of 93 patients scheduled for standard phacoemulsification. RESULTS: Mean plasminogen activity in patients with non-exsudative AMD (n = 24) revealed to be 0.06%N, in patients with exudative AMD (n = 7) 0.03%N and in healthy controls (n = 43) 0.02%N (p = 0.38, ANOVA). Plasminogen activator inhibitor I (PAI-1) was detected in neither group. Alpha2-antiplasmin activity was 1.61 U/ml in the non-exudative AMD group (n = 27), 0 U/ml in the exudative AMD group (n = 7) and 0.54 U/ml in the control group (n = 48) (p = 0.1, ANOVA). Concentrations of plasmin-a2-antiplasmin complex (PAP) were detected at levels of 17.91 ng/ml in the non-exudative AMD group (n = 11), of 16.6 ng/ml in the exudative AMD group (n = 5), and of 17.43 ng/ml in the control group (n = 14) (p = 0.92, ANOVA). CONCLUSIONS: Plasminogen is present with a very low activity in aqueous humor. There are no significant differences in aqueous humor concentrations or activities of plasminogen and other components of the fibrinolytic system between patients with non-exudative AMD, exudative AMD, and healthy controls. Further studies should investigate vitreous samples instead of aqueous humor samples. A careful and accurate workup of obtained intraocular fluids is needed to detect the low concentrations and activities of the parameters analyzed.

Intravitreal functional plasminogen is elevated in central retinal vein occlusion.

PURPOSE: To detect intravitreal functional plasminogen in vitreous samples of patients with recent onset of central retinal vein occlusion (CRVO) and to demonstrate significantly higher intravitreal plasminogen in CRVO patients in comparison to controls. METHODS: Prospective clinical case series of 13 consecutive patients with recent onset of CRVO scheduled for core pars plana vitrectomy and 10 consecutive patients undergoing standard pars plana vitrectomy for routine macular surgery or vitreal floater removal. In all 23 cases, vitreous taps were extracted from the central vitreous body, and plasminogen was functionally determined in a new ultrasensitive p-nitroanilide reaction after activation with streptokinase (100% of normal, %N = functional plasminogen in pooled normal citrated plasma). RESULTS: Plasminogen was detected in all analyzed samples (n = 23), and mean plasminogen was revealed to be 1.33 ± 1.73% (mean ± SD), with a range of 0.03-7.8%N. Patients with recent onset of CRVO exhibited significantly higher intravitreal plasminogen (2.19 ± 1.89%N) in comparison to controls (0.20 ± 0.21%N; p < 0.001, Mann-Whitney U test). CONCLUSION: Due to significantly increased intravitreal plasminogen in patients with recent onset of CRVO, intravitreally administered tissue plasminogen activator might be an option to induce posterior vitreous detachment (enzymatic vitreolysis) in CRVO patients.

[Diagnosis, treatment and monitoring of diabetic eye disease (Update 2023)]. / Diagnostik, Therapie und Verlaufskontrolle der diabetischen Augenerkrankung (Update 2023).

Diabetes mellitus can cause diabetic retinopathy, diabetic macular edema, optic neuropathy, cataract or dysfunction of the eye muscles. The incidence of these disorders correlates with disease duration and quality of metabolic control. Regular ophthalmological examinations are needed to prevent sight-threatening advanced stages of diabetic eye diseases.

Sampling aqueous humor: anterior segment anatomy, anesthetic and surgical technique, and rates of yield.

PURPOSE: To evaluate anterior segment anatomy and anesthetic and surgical techniques with respect to the amount of aqueous humor (AH) that can be sampled out of the anterior chamber (AC) at the beginning of standard cataract removal procedures (phacoemulsification). METHODS: In a prospective survey, volumes of sampled AH from 123 eyes (110 patients) were analyzed in regard to AC anatomy (anterior chamber depth, ACD) and different anesthetic techniques (local and general anesthesia). RESULTS: 107 eyes (87%) were included into our analysis, and 16 eyes (13%) had to be excluded due to failure of AH collection. We found a significant positive association between ACD and obtained AH volume (p=0.007). In general anesthesia, a strong trend to acquire more AH in comparison to local anesthesia was apparent, but statistical significance failed (p=0.167). Different anesthetic techniques seem to have no significant influence on ACD (p=0.169). No training curve for the individual surgeon was obtained. No complications were observed. CONCLUSION: When AH sampling is performed in eyes with a deep AC and when the procedure is performed under general anesthesia, more AH can be aspirated.

Radial optic neurotomy for central retinal vein occlusion: long-term retinal perfusion outcome.

BACKGROUND/AIMS: To analyze the long-term changes in retinal perfusion and functional improvement induced by radial optic neurotomy (RON) in central retinal vein occlusion (CRVO). METHODS: Sixty-three eyes of 63 consecutive patients with CRVO were included. Twenty-eight (44.5%) patients underwent RON and 35 (55.5%) were followed as a control group. Time of arteriovenous transit and visual acuity were determined at baseline and after 1-year follow-up. RESULTS: After 1 year, retinal perfusion status improved in 63.1% of operated eyes and 14.3% of controls (p = 0.048). The improvement in arteriovenous retinal transit was statistically significant (p = 0.023) only in the RON group. The visual improvement in the RON group was significantly better (p = 0.043) than in the control group. Moreover, the development of chorioretinal anastomosis was significantly higher (p = 0.036) after RON than in controls and correlated with better functional results. In operated eyes there was a lower incidence of CRVO-related complications. CONCLUSION: RON improved retinal perfusion and achieved a better functional outcome. The measurement of perfusion changes as presented here may be useful for monitoring CRVO and assessing other treatment modalities.

[Diagnosis, treatment and monitoring of diabetic eye disease (Update 2019)]. / Diagnose, Therapie und Verlaufskontrolle der diabetischen Augenerkrankung (Update 2019).

Diabetes mellitus can cause diabetic retinopathy, diabetic macular edema, optic neuropathy, cataract or dysfunction of the eye muscles. The incidence of these defects correlates with disease duration and quality of metabolic control. Recommendations of the Austrian Diabetes Association for diagnosis, therapeutic procedures and requirements for adequate follow-up depending on stage of diabetic eye disease are summarized.

Three simple approaches to visualize the transparent vitreous cortex during vitreoretinal surgery.

BACKGROUND: Initial historical considerations to perform a pars plana vitrectomy were made for opaque vitreous cortex due to dense asteroid hyalosis or vitreous hemorrhages. However, current indications for vitreoretinal surgery include mainly vitrectomies in the presence of a clear vitreous, for example retinal detachments, epiretinal membranes or macular holes, thus visualization of the transparent vitreous gel facilitates proper vitreous removal. MATERIALS AND METHODS: The transparent structure of the vitreous cortex as well as the thin epiretinal membrane may become visible during surgery by mild vitreous hemorrhages or intravitreous application of 0.05 ml crystalline triamcinolone acetonide. Eyes with a significant breakdown of the blood-retinal barrier accumulate intravenously applied vital dyes, for example fluorescein, in the vitreous cavity. RESULTS: Mild accidental intraoperative bleedings or intended injection of 0.05 ml autologous blood may help to stain transparent vitreous structures and visualize the remaining vitreous. Intravitreous triamcinolone crystals attach to the surface of the vitreous cortex, bursa premacularis or retina itself allowing better visualization of a controlled vitreous removal. A preoperative diagnostic fluorescein angiography in eyes with active uveitis or diabetic retinopathy may lead to a moderate accumulation of the dye in the vitreous cavity and greenish staining of the vitreous cortex at the vitreoretinal interface. DISCUSSION: A safe and complete removal of clear vitreous or transparent membranes may be achieved by the intraoperative application of autologous blood or triamcinolone. The preoperative systemic application of fluorescein greatly enhances the visualization of previously clear structures.