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Purpose: To evaluate the 2-year surgical treatment outcome in glaucoma patients., Methods: A retrospective, single-center, interventional study was performed on 160 eyes of 125 patients suffering glaucoma, including POAG (82 eyes), pseudoexfoliation (PEX) (59 eyes), pigment dispersion (8 eyes), and secondary glaucoma (2 eyes). Eyes with uncontrolled intraocular pressure (IOP) or signs of glaucoma progression despite medical treatment were included to undergo either trabeculectomy (TE), XEN implantation, combined TE with phacoemulsification (TE + IOL), or XEN implantation with phacoemulsification surgery (XEN + IOL). Primary efficacy outcome was the mean IOP reduction. Secondary outcome was the mean reduction in the number of medications. The data were compared at baseline vs.1 day, 1 week, and 1, 3, 6, 12, and 24 months following surgery. For statistical evaluation, ANOVA-based linear mixed-effects models were performed with SPSS., Results: The mean IOP reduction in a 2-year follow-up was 30.31% (22.17 vs. 15.45 mmHg, p < 0.001). The mean number of antiglaucoma medications was reduced from 2.87 to 0.58 (p = 0.001), where TE alone or combined surgeries seemed to be more effective than isolated XEN surgery. Transient IOP hypotony on the first postoperative day occurred in PEX patients following TE surgery (p = 0.024). At 6 months, PEX patients with isolated XEN surgery showed a transient IOP increase, whereas those after combined TE + IOL surgery showed the lowest IOP within the PEX group compared to other glaucoma patients (p < 0.026)., Conclusions: After 2 years, all performed glaucoma surgeries achieved a significant reduction in IOP and the number of antiglaucoma medications., Competing Interests: All authors share same contribution and declare no conflict of interest., (Thieme. All rights reserved.)

The pathogenesis of the glaucomatous optic neuropathy (GON) is an ongoing bone of contention. While the role of intraocular pressure (IOP) is well known, it is also clear that a variety of other factors, particularly those of a vascular nature, are involved as well. In contrast to other eye diseases, it is an unstable oxygen supply, as opposed to chronic hypoxia, that contributes to GON. The major cause of fluctuations in the local oxygen tension is an unstable ocular blood flow (OBF). OBF, in turn, fluctuates if the IOP spikes, blood pressure drops, or OBF autoregulation is defective. The main reason for disturbed autoregulation is a primary vascular dysregulation (PVD), particularly in the context of the so-called Flammer syndrome. Unstable oxygen tension leads to local oxidative stress with many detrimental effects, such as the activation of glial cells, which alters their morphology and gene expression. As a consequence, the local concentrations of nitric oxide and the metalloproteinases increase. The metalloproteinases digest extracellular matrix and thereby contribute to tissue remodelling. The short-lived nitric oxide easily diffuses into the neighbouring neuronal axons, allowing a fusion with the superoxide anion and thereby generating the cell-damaging peroxynitrite. Both this tissue remodelling and damage of the axons contribute to the development and progression of GON., (Georg Thieme Verlag KG Stuttgart · New York.)

Purpose: To test a new 2-flash multifocal electroretinogram (mfERG) paradigm in glaucoma using a reduced light intensity of the m-frame flash as opposed to the global flash, as it has been suggested that this may increase the responses induced by the global flash, which has been the part of the mfERG response where most changes have been noted in glaucoma., Methods: A mfERG was recorded from one eye of 22 primary open angle glaucoma (POAG) patients [16 normal tension glaucoma (NTG), 6 high tension glaucoma (HTG)] and 20 control subjects. A binary m-sequence (2^13-1, Lmax 100 cd/m2, Lmin<1 cd/m2), followed by two global flashes (Lmax 200 cd/m2) at an interval of 26 ms (VERIS 6.0™, FMSIII), was used. The stimulus array consisted of 103 hexagons. Retinal signals were amplified (gain=50 K) and bandpass filtered at 1-300 Hz. For each focal response, the root mean square was calculated. We analyzed 5 larger response averages (central 15° and 4 adjoining quadrants) as well as 8 smaller response averages (central 10° and 7 surrounding response averages of approximately 7° radius each). Three epochs were analyzed: the direct component at 15-45 ms (DC) and the following two components induced by the effects of the preceding focal flash on the response to the global flashes at 45-75 ms (IC-1) and at 75-105 ms (IC-2). Statistical analysis was performed using linear mixed effects models adjusted for age., Results: Responses differed significantly between POAG patients and controls in all central response averages. This difference was larger for the central 10° than for the response average of the central 15°. While these observations held true for all response epochs analyzed, the DC differed least and the IC-1 most when POAG was compared to control. For POAG, the most sensitive differential measure was IC-1 of the central 10° with an area under the ROC curve of 0.78. With a cutoff value of 12.52 nV/deg2, 80% of the POAG patients (100% HTG, 69% NTG) were correctly classified as abnormal, while 77% of the control subjects were correctly classified as normal. When the results of the mfERG were compared to the visual fields, there was a tendency for the mfERG to decrease as the mean defect increased. However, this correlation was only significant in the superior nasal quadrant when the IC-1 of the mfERG was compared to the corresponding area of the visual field., Conclusion: When compared to findings from previous studies, reducing the luminance of the m-frame flash in the 2-global flash paradigm did not increase the sensitivity and specificity of the mfERG to detect glaucoma further.

Purpose To evaluate relationship between vascular dysregulation and retinal oxygen demand in normal tension glaucoma (NTG). Methods Retinal vascular responses of 27 eyes of 18 Caucasian (10♀ :8♂) individuals with NTG were measured. Subjects were grouped based on their median vascular responsiveness. In each group, retinal vessel oxygen saturation was measured in arterioles (A- SO2) and in venules (V- SO2) within the peri-papillary annulus with the oximetry tool of Retinal Vessel Analyser (IMEDOS Systems UG, Jena, Germany). Retinal nerve fiber layer thickness (RNFL) was measured with spectral domain optical coherence tomography (Carl Zeiss Meditec, Dublin, CA, USA) and visual field (VF) with Octopus perimeter (Haag-Streit International, Switzerland). Retinal oxygen concentration per micron of nerve fiber layer thickness (O2-C) was calculated as follows; the difference of aretrio-venous oxygen saturation (A-V SO2) was divided to the mean RNFL thickness. A linear mixed-effects model was applied (IBM SPSS®) Results The eyes were grouped based on their vascular responsiveness (group1 ≤ 2.90%; n = 13, group 2 > 2.90%; n = 14). In group1 and in group2, mean A- SO2, V- SO2 and A-V SO2 were 96.50% (±4.38); 97.77% (±3.03) (p=0.517), 62.89% (±6.23); 60.71% (±6.28) (p = 0.391), 34.64%(±4.51); 36.68% (±5.27) (p = 0.294), respectively. Subjects in group 1 showed higher O2-C 0.488%/µ (±0.0848) than in group2 0.434%/µ (±0.0551) (p = 0.027). Mean age (65.45 y (±11.7)) and VF(dB) defect (4.7 dB (± 3.6), 3.4 dB (±5.2) were not statistically different between groups (p = 0 > 141). In group 1, RNFL thickness was significantly less than in group 2 (72.23 µm (±12.1); 85.31 µm (±13.67) (p=0.014). Conclusions Oxygen demand was increased in patients with excessive vascular dysregulation, while mean SO2 values were not related to age and/or flicker responses. This conclusion remains to be conformed in further studies. [ABSTRACT FROM AUTHOR]