Julia Beutel

The retinal tolerance to bevacizumab in co‐application with a recombinant tissue plasminogen activator

Aim: To investigate the retinal toxicity of bevacizumab in co-application with a commercially available recombinant tissue plasminogen activator (rt-PA), and to facilitate a new therapeutic concept in the treatment of massive subretinal haemorrhage caused by neovascular age-related macular degeneration (AMD). Methods: Isolated bovine retinas were perfused with an oxygen-preincubated nutrient solution. The electroretinogram (ERG) was recorded as a transretinal potential using Ag/AgCl electrodes. Bevacizumab (0.25 mg/ml) and rt-PA (20 μg/ml) were added to the nutrient solution for 45 min. Thereafter, the retina was reperfused for 60 min with normal nutrient solution. Similarly, the effects of rt-PA (20 μg/ml, 60 μg/ml and 200 μg/ml) on the a- and b-wave amplitudes were investigated. The percentages of a- and b-wave reduction during application and at washout were calculated. Results: During application of bevacizumab (0.25 mg/ml) in co-application with 20 μg/ml (rt-PA), the ERG amplitudes remained stable. The concentrations of rt-PA alone (20 μg/ml and 60 μg/ml) did not induce significant reduction of the b-wave amplitude. In addition, 20 μg/ml rt-PA did not alter the a-wave amplitude. However, 60 μg/ml rt-PA caused a slight but significant reduction of the a-wave amplitude. A full recovery was detected for both concentrations during the washout. At the highest tested concentration of 200 μg/ml rt-PA, a significant reduction of the a- and b-wave amplitudes was provoked during the exposure. The reduction of ERG amplitudes remained irreversible during the washout. Conclusion: The present study suggests that a subretinal injection of 20 µg/ml rt-PA in co-application with bevacizumab (0.25 mg/ml) for the treatment of massive subretinal haemorrhage seems possible. This is a safety study. Therefore, we did not test the clinical effectiveness of this combined treatment.

Full macular translocation (FMT) versus photodynamic therapy (PDT) with verteporfin in the treatment of neovascular age-related macular degeneration: 2-year results of a prospective, controlled, randomised pilot trial (FMT-PDT)

BackgroundThe purpose of this study was to compare full macular translocation (FMT) with photodynamic therapy (PDT) in the treatment of neovascular age-related macular degeneration (AMD).MethodsIn a prospective, randomised, non-masked, monocenter, pilot-trial, 50 eyes of 50 patients were assigned to either FMT or PDT. Baseline and control examinations in 3-monthly intervals over a 12-month period included standardized protocol refraction, visual acuity testing and fluorescein angiography. Primary outcome measurements were made to establish the change in distant visual acuity from the baseline to the 12-month examination. The statistical analyses were carried out on the intent-to-treat principle.ResultsThe improvement of one or more ETDRS lines was 56% (14/25) of the eyes in the FMT and 16% (4/25) of the eyes in the PDT arm (P=0.007). Twenty eyes (80%) in the FMT and 16 eyes (64%) in the PDT group had less than three ETDRS lines of vision loss (P=0.35). Retinal detachment (six eyes) and diplopia (five patients) were recorded in the FMT group. None of the eyes treated in the FMT group had phtysis.ConclusionThis pilot study showed that no statistically significant difference existed between the FMT and PDT in terms of the vision loss of less than three ETDRS lines in eyes with neovascular AMD. The chance of vision improvement was significantly higher for the patients in the FMT group. However, in the era of promising therapy with anti-vascular endothelial growth factor for neovascular AMD, FMT should not be offered as a standard primary procedure for neovascular AMD.

Visualization of Circulating Melanoma Cells in Peripheral Blood of Patients with Primary Uveal Melanoma

Purpose: In patients with uveal melanoma, tumor cell dissemination and subsequent formation of metastases are confined mainly to the hematogenous route. Here, we sought to isolate circulating melanoma cells in peripheral blood of patients with primary uveal melanoma and clinically localized disease. Experimental Design: Blood samples from 52 patients with clinically localized uveal melanoma and from 20 control individuals were prospectively collected before therapy of the primary tumor. Tumor cells expressing the melanoma-associated chondroitin sulfate proteoglycan were enriched by immunomagnetic cell sorting and visualized by immunocytologic staining. Results were compared with clinical data at presentation. Results: In 10 of 52 patients [19%; 95% confidence interval (95% CI), 10-33%], between 1 and 5 circulating melanoma cells were detected in 50 mL peripheral blood. No melanoma-associated chondroitin sulfate proteoglycan–positive cells were detected in any of the 20 controls examined. The presence of tumor cells in peripheral blood was associated with ciliary body invasion [odds ratio (OR), 20.0; 95% CI, 3.0-131.7], advanced local tumor stage (OR, 6.7; 95% CI, 1.8-25.4), and anterior tumor localization (OR, 4.0; 95% CI, 1.2-12.7), all established factors for uveal melanoma progression. Conclusions: Immunomagnetic enrichment enables detection of intact melanoma cells in peripheral blood of patients with clinically localized ocular disease. Visualization and capturing of these cells provide a unique tool for characterizing potentially metastasizing tumor cells from a primary melanoma at an early stage of the disease.

TREATMENT OF CHRONIC OCULAR HYPOTONY WITH INTRAOCULAR APPLICATION OF SODIUM HYALURONATE

Aim: The aim of the study was to report the functional and morphological outcome of intraocular injection of sodium hyaluronate for treatment of chronic ocular hypotony (COH). Methods: We reviewed the digital chart records of patients with COH who had received one or more injections of intravitreal or intracameral sodium hyaluronate (1.4% or 2.3%). The changes in the best corrected visual acuity (BCVA) and intraocular pressure (IOP) after treatment were recorded. Results: Thirty-two eyes of 32 patients with a mean age of 56.8 years were analysed. Previous vitreoretinal surgery had been performed on all eyes for either ocular-penetrating trauma (six eyes), chronic uveitis (six eyes), full macular translocation (five eyes) or retinal detachment (15 eyes). Mean follow-up time after the first intraocular injection was 29.7 months. BCVA (logMAR) at the baseline and the last follow-up visit were 1.84 (SE 0.65) and 1.82 (SE 0.72), respectively (p = 0.87). The mean IOP at the baseline increased from 2.28 (SE 0.27) mmHg to 7.12 (SE 1.03) mmHg at the last visit (p<0.001). At the final follow-up, 20 eyes (62.5%) had an IOP higher than 5 mmHg and 24 eyes (75%) had an unchanged or improved BCVA. Conclusions: Stabilisation of the IOP and vision in some eyes with COH following vitreoretinal surgery can be achieved with intraocular injection of sodium hyaluronate. Large case-series and long-term follow-up are necessary to confirm the beneficial role of intraocular sodium hyaluronate injections in such eyes.

The effects of triamcinolone crystals on retinal function in a model of isolated perfused vertebrate retina

A good clinical experience of intravitreal triamcinolone acetonide (TA) has been reported in several studies, but there are growing indications that epiretinal crystals of TA exhibit retinal toxicity. To investigate the effects of TA on retinal function we used a model of an electrophysiological in vitro technique for testing retinal toxicity. Isolated bovine retinas were perfused with an oxygen saturated nutrient solution. The electroretinogram (ERG) was recorded as a transretinal potential using Ag/AgCl electrodes. After reaching stable ERG-amplitudes TA at the maximum solubility equilibrium (36 microg/ml) was either applied to the nutrient solution for 45 min or TA was administered epiretinally at concentrations (1 mg/ml, 4 mg/ml, 8 mg/ml, 20 mg/ml and 40 mg/ml) above the maximum solubility equilibrium to assure direct contact of the TA crystals with the isolated perfused retinas. After that the retinas were reperfused for 75 min with the standard nutrient solution. The percentage of a- and b-wave reduction directly after the application and at the washout was calculated. To assess the effects of TA at the level of the ganglion cell layer a Viability/Cytotoxicity Kit for mammalian cells was used. No changes of the ERG-amplitudes were detected during the exposure to 36 microg/ml TA for 45 min (b-wave: 9.6 microV+/-2.1 vs. 8 microV+/-2.1 (p=0.135); a-wave: -11 microV+/-2.7 vs. -10.6 microV+/-2.3 (p=0.889)) and at the washout (b-wave: 8 microV+/-2.1 vs. 8.3 microV+/-2.4 (p=0.18); a-wave: -10.6 microV+/-2.3 vs. -12 microV+/-2.6 (p=0.225)). At concentrations higher than 1mg/ml TA induced a decrease of the a- and b-wave in a concentration dependent manner. These changes were reversible for concentrations of TA up to 20mg/ml (b-wave: 9 microV+/-2.4 vs. 6.6 microV+/-2.5 (p=0.08); a-wave: -11.4 microV+/-2.0 vs. -11.2 microV+/-2.2 (p=0.37)), but irreversible at 40 mg/ml even at the end of the washout (b-wave: 9.8 microV+/-1.9 vs. 3 microV+/-1.7 (p=0.009); a-wave: -9.8 microV+/-2.1 vs. -2.6 microV+/-2.1 (p=0.001)). Histological examination of the preparations revealed a dramatic ganglion cell death, in which an application of 20mg/ml and 40 mg/ml TA led to a 60.53% (p=0.013) and 82.35% (p=0.002) ganglion cell death, respectively. The epiretinal application of 4 mg/ml TA and higher resulted in distinct effects on the ERG of the isolated perfused retinas. Ganglion cell death was induced at a concentration of 20mg/ml and higher. TA shows an asymmetric and partly high concentrated distribution after intravitreal application. Therefore, we consider concentrations of 4 mg/ml and higher might be toxic and should be avoided in clinical use.

Current and future therapies for age-related macular degeneration

Background: Age-related macular degeneration is the leading cause of blindness, with an increasing incidence as the elderly population expands. Objective: In this article we review current therapeutic strategies and discuss possible future targets. Methods: A review of the literature and ongoing clinical trials was undertaken. Results: Currently, established therapies for neovascular AMD-like photodynamic therapy and anti-VEGF therapies allow stabilization or even improvement of vision. Potential future drugs under development for advanced AMD or its prevention target the signal transduction cascade of different angiogenic molecules. These drugs intervene at different levels of the involved processes including the RNA production and specific protein expression as well as inflammatory, apoptotic, or metabolic processes. Conclusion: Combining different strategies targeting angiogenesis, inflammation and apoptosis, or interfering early in – or even prior to – the formation of choroidal neovascularization, may improve the future management of age-related macular degeneration.

[Vitreal-induced RPE cell traction. Investigation of pathological vitreous samples in an in vitro contraction model].

ZusammenfassungHintergrundZielsetzung dieser Studie war, die Kontraktilität von retinalen Pigmentepithel- (RPE-)Zellen zu quantifizieren, die durch bioaktive Faktoren pathologischer Glaskörperproben induziert wird.Material und MethodenUnter Verwendung eines In-vitro-Kontraktionsmodells konnten die Aktivität von Glaskörperproben unterschiedlicher vitreoretinaler Erkrankungen untersucht werden. Dazu wurden transdifferentierte porcine RPE-Zellen auf hemisphärische Typ-I-Kollagen-Gele aufgebracht. Nach Zugabe der Glaskörperproben [physiologisch (n=6); rhegmatogene Ablatio (n=11); proliferative Vitreoretinopathie (PVR, n=10); proliferative diabetische Retinopathie (PDR, n=6)] wurde die induzierte Gelkontraktion bestimmt.ErgebnisseDie spezifische Aktivität der unklassifizierten Proben betrug 0,04 (Median, Spannweite, SW: 0–0,08). Glaskörperproben, die von Patienten mit verschiedenen PVR-Stadien gewonnen wurden, wiesen eine spezifische Aktivität von 0,45 (Median, SW: 0,03–1,45) auf. Die Glaskörperproben von rhegmatogen bedingten Netzhautablösungen zeigten eine Aktivität von 0,13 (Median, SW: 0,01–0,93). Die spezifische Aktivität von Glaskörperproben von Patienten mit diabetischer Retinopathie betrug 0,17 (Median, SW: 0,06–0,29). Die mittlere spezifische Aktivität und Gesamtaktivität dieser Gruppen waren signifikant im Vergleich zu den unklassifizierten Proben bzw. den Basiswerten erhöht (p<0,05).SchlussfolgerungPathologische Glaskörperproben unterschiedlicher vitreoretinaler Erkrankungen enthalten ausreichende Mengen von biologisch aktiven Substanzen, die eine Kontraktion von Extrazellulärmatrix induzieren können.AbstractBackgroundThe aim of this study was to quantify the contraction of retinal pigment epithelium cells (RPE) induced by bioactive factors in pathological vitreous samples.Material and methodsUsing an in vitro contraction assay, the contraction-stimulating activity of vitreous samples of different vitreoretinal pathologies was evaluated. Transdifferentiated porcine RPE cells were placed on hemispherical type I collagen gel. After exposure to pathological vitreous samples derived from different entities (physiological (n=6), rhegmatogenous retinal detachment (n=11), proliferative vitreoretinopathy (PVR) (=10), proliferative diabetic retinopathy (n=6)) the induced gel contraction was determined.ResultsThe specific activity of the unclassified samples was 0.04 (median, range: 0-0.08). Vitreous samples derived from patients diagnosed as having any grade of PVR displayed a specific activity of 0.45 (median, range: 0.03-1.45). Samples removed from patients with rhegmatogenous retinal detachment disclosed a specific activity of 0.13 (median, range: 0.01-0.93). The specific activity of vitreous samples removed from patients with diabetic retinopathy had a specific activity of 0.17 (median, range: 0.06-0.29). The mean specific and total activities of these groups were significantly elevated above the unclassified or baseline values (p<0.05).ConclusionPathological vitreous samples of different vitreoretinal pathologies contain sufficient amounts of biologically active factors to induce extracellular matrix contraction.BACKGROUND The aim of this study was to quantify the contraction of retinal pigment epithelium cells (RPE) induced by bioactive factors in pathological vitreous samples. MATERIAL AND METHODS Using an in vitro contraction assay, the contraction-stimulating activity of vitreous samples of different vitreoretinal pathologies was evaluated. Transdifferentiated porcine RPE cells were placed on hemispherical type I collagen gel. After exposure to pathological vitreous samples derived from different entities (physiological (n=6), rhegmatogenous retinal detachment (n=11), proliferative vitreoretinopathy (PVR) (=10), proliferative diabetic retinopathy (n=6)) the induced gel contraction was determined. RESULTS The specific activity of the unclassified samples was 0.04 (median, range: 0-0.08). Vitreous samples derived from patients diagnosed as having any grade of PVR displayed a specific activity of 0.45 (median, range: 0.03-1.45). Samples removed from patients with rhegmatogenous retinal detachment disclosed a specific activity of 0.13 (median, range: 0.01-0.93). The specific activity of vitreous samples removed from patients with diabetic retinopathy had a specific activity of 0.17 (median, range: 0.06-0.29). The mean specific and total activities of these groups were significantly elevated above the unclassified or baseline values (p<0.05). CONCLUSION Pathological vitreous samples of different vitreoretinal pathologies contain sufficient amounts of biologically active factors to induce extracellular matrix contraction.

Vitreal induzierte RPE-Zell-Traktion

ZusammenfassungHintergrundZielsetzung dieser Studie war, die Kontraktilität von retinalen Pigmentepithel- (RPE-)Zellen zu quantifizieren, die durch bioaktive Faktoren pathologischer Glaskörperproben induziert wird.Material und MethodenUnter Verwendung eines In-vitro-Kontraktionsmodells konnten die Aktivität von Glaskörperproben unterschiedlicher vitreoretinaler Erkrankungen untersucht werden. Dazu wurden transdifferentierte porcine RPE-Zellen auf hemisphärische Typ-I-Kollagen-Gele aufgebracht. Nach Zugabe der Glaskörperproben [physiologisch (n=6); rhegmatogene Ablatio (n=11); proliferative Vitreoretinopathie (PVR, n=10); proliferative diabetische Retinopathie (PDR, n=6)] wurde die induzierte Gelkontraktion bestimmt.ErgebnisseDie spezifische Aktivität der unklassifizierten Proben betrug 0,04 (Median, Spannweite, SW: 0–0,08). Glaskörperproben, die von Patienten mit verschiedenen PVR-Stadien gewonnen wurden, wiesen eine spezifische Aktivität von 0,45 (Median, SW: 0,03–1,45) auf. Die Glaskörperproben von rhegmatogen bedingten Netzhautablösungen zeigten eine Aktivität von 0,13 (Median, SW: 0,01–0,93). Die spezifische Aktivität von Glaskörperproben von Patienten mit diabetischer Retinopathie betrug 0,17 (Median, SW: 0,06–0,29). Die mittlere spezifische Aktivität und Gesamtaktivität dieser Gruppen waren signifikant im Vergleich zu den unklassifizierten Proben bzw. den Basiswerten erhöht (p<0,05).SchlussfolgerungPathologische Glaskörperproben unterschiedlicher vitreoretinaler Erkrankungen enthalten ausreichende Mengen von biologisch aktiven Substanzen, die eine Kontraktion von Extrazellulärmatrix induzieren können.AbstractBackgroundThe aim of this study was to quantify the contraction of retinal pigment epithelium cells (RPE) induced by bioactive factors in pathological vitreous samples.Material and methodsUsing an in vitro contraction assay, the contraction-stimulating activity of vitreous samples of different vitreoretinal pathologies was evaluated. Transdifferentiated porcine RPE cells were placed on hemispherical type I collagen gel. After exposure to pathological vitreous samples derived from different entities (physiological (n=6), rhegmatogenous retinal detachment (n=11), proliferative vitreoretinopathy (PVR) (=10), proliferative diabetic retinopathy (n=6)) the induced gel contraction was determined.ResultsThe specific activity of the unclassified samples was 0.04 (median, range: 0-0.08). Vitreous samples derived from patients diagnosed as having any grade of PVR displayed a specific activity of 0.45 (median, range: 0.03-1.45). Samples removed from patients with rhegmatogenous retinal detachment disclosed a specific activity of 0.13 (median, range: 0.01-0.93). The specific activity of vitreous samples removed from patients with diabetic retinopathy had a specific activity of 0.17 (median, range: 0.06-0.29). The mean specific and total activities of these groups were significantly elevated above the unclassified or baseline values (p<0.05).ConclusionPathological vitreous samples of different vitreoretinal pathologies contain sufficient amounts of biologically active factors to induce extracellular matrix contraction.BACKGROUND The aim of this study was to quantify the contraction of retinal pigment epithelium cells (RPE) induced by bioactive factors in pathological vitreous samples. MATERIAL AND METHODS Using an in vitro contraction assay, the contraction-stimulating activity of vitreous samples of different vitreoretinal pathologies was evaluated. Transdifferentiated porcine RPE cells were placed on hemispherical type I collagen gel. After exposure to pathological vitreous samples derived from different entities (physiological (n=6), rhegmatogenous retinal detachment (n=11), proliferative vitreoretinopathy (PVR) (=10), proliferative diabetic retinopathy (n=6)) the induced gel contraction was determined. RESULTS The specific activity of the unclassified samples was 0.04 (median, range: 0-0.08). Vitreous samples derived from patients diagnosed as having any grade of PVR displayed a specific activity of 0.45 (median, range: 0.03-1.45). Samples removed from patients with rhegmatogenous retinal detachment disclosed a specific activity of 0.13 (median, range: 0.01-0.93). The specific activity of vitreous samples removed from patients with diabetic retinopathy had a specific activity of 0.17 (median, range: 0.06-0.29). The mean specific and total activities of these groups were significantly elevated above the unclassified or baseline values (p<0.05). CONCLUSION Pathological vitreous samples of different vitreoretinal pathologies contain sufficient amounts of biologically active factors to induce extracellular matrix contraction.

Vitreal induzierte RPE-Zell-Traktion@@@Vitreal-induced RPE cell traction: Untersuchung pathologischer Glaskörperproben in einem In-vitro-Kontraktionsmodell@@@Investigation of pathological vitreous samples in an in vitro contraction model

ZusammenfassungHintergrundZielsetzung dieser Studie war, die Kontraktilität von retinalen Pigmentepithel- (RPE-)Zellen zu quantifizieren, die durch bioaktive Faktoren pathologischer Glaskörperproben induziert wird.Material und MethodenUnter Verwendung eines In-vitro-Kontraktionsmodells konnten die Aktivität von Glaskörperproben unterschiedlicher vitreoretinaler Erkrankungen untersucht werden. Dazu wurden transdifferentierte porcine RPE-Zellen auf hemisphärische Typ-I-Kollagen-Gele aufgebracht. Nach Zugabe der Glaskörperproben [physiologisch (n=6); rhegmatogene Ablatio (n=11); proliferative Vitreoretinopathie (PVR, n=10); proliferative diabetische Retinopathie (PDR, n=6)] wurde die induzierte Gelkontraktion bestimmt.ErgebnisseDie spezifische Aktivität der unklassifizierten Proben betrug 0,04 (Median, Spannweite, SW: 0–0,08). Glaskörperproben, die von Patienten mit verschiedenen PVR-Stadien gewonnen wurden, wiesen eine spezifische Aktivität von 0,45 (Median, SW: 0,03–1,45) auf. Die Glaskörperproben von rhegmatogen bedingten Netzhautablösungen zeigten eine Aktivität von 0,13 (Median, SW: 0,01–0,93). Die spezifische Aktivität von Glaskörperproben von Patienten mit diabetischer Retinopathie betrug 0,17 (Median, SW: 0,06–0,29). Die mittlere spezifische Aktivität und Gesamtaktivität dieser Gruppen waren signifikant im Vergleich zu den unklassifizierten Proben bzw. den Basiswerten erhöht (p<0,05).SchlussfolgerungPathologische Glaskörperproben unterschiedlicher vitreoretinaler Erkrankungen enthalten ausreichende Mengen von biologisch aktiven Substanzen, die eine Kontraktion von Extrazellulärmatrix induzieren können.AbstractBackgroundThe aim of this study was to quantify the contraction of retinal pigment epithelium cells (RPE) induced by bioactive factors in pathological vitreous samples.Material and methodsUsing an in vitro contraction assay, the contraction-stimulating activity of vitreous samples of different vitreoretinal pathologies was evaluated. Transdifferentiated porcine RPE cells were placed on hemispherical type I collagen gel. After exposure to pathological vitreous samples derived from different entities (physiological (n=6), rhegmatogenous retinal detachment (n=11), proliferative vitreoretinopathy (PVR) (=10), proliferative diabetic retinopathy (n=6)) the induced gel contraction was determined.ResultsThe specific activity of the unclassified samples was 0.04 (median, range: 0-0.08). Vitreous samples derived from patients diagnosed as having any grade of PVR displayed a specific activity of 0.45 (median, range: 0.03-1.45). Samples removed from patients with rhegmatogenous retinal detachment disclosed a specific activity of 0.13 (median, range: 0.01-0.93). The specific activity of vitreous samples removed from patients with diabetic retinopathy had a specific activity of 0.17 (median, range: 0.06-0.29). The mean specific and total activities of these groups were significantly elevated above the unclassified or baseline values (p<0.05).ConclusionPathological vitreous samples of different vitreoretinal pathologies contain sufficient amounts of biologically active factors to induce extracellular matrix contraction.BACKGROUND The aim of this study was to quantify the contraction of retinal pigment epithelium cells (RPE) induced by bioactive factors in pathological vitreous samples. MATERIAL AND METHODS Using an in vitro contraction assay, the contraction-stimulating activity of vitreous samples of different vitreoretinal pathologies was evaluated. Transdifferentiated porcine RPE cells were placed on hemispherical type I collagen gel. After exposure to pathological vitreous samples derived from different entities (physiological (n=6), rhegmatogenous retinal detachment (n=11), proliferative vitreoretinopathy (PVR) (=10), proliferative diabetic retinopathy (n=6)) the induced gel contraction was determined. RESULTS The specific activity of the unclassified samples was 0.04 (median, range: 0-0.08). Vitreous samples derived from patients diagnosed as having any grade of PVR displayed a specific activity of 0.45 (median, range: 0.03-1.45). Samples removed from patients with rhegmatogenous retinal detachment disclosed a specific activity of 0.13 (median, range: 0.01-0.93). The specific activity of vitreous samples removed from patients with diabetic retinopathy had a specific activity of 0.17 (median, range: 0.06-0.29). The mean specific and total activities of these groups were significantly elevated above the unclassified or baseline values (p<0.05). CONCLUSION Pathological vitreous samples of different vitreoretinal pathologies contain sufficient amounts of biologically active factors to induce extracellular matrix contraction.