Accuracy of Bruch's membrane opening minimum rim width and retinal nerve fiber layer thickness in glaucoma diagnosis depending on optic disc size.

BACKGROUND/AIM: The aim of this paper is to compare retinal nerve fiber layer thickness (RNFL) and Bruch's membrane opening-based minimum rim width (BMO-MRW) in terms of their performance in detecting early and moderate/advanced glaucoma using receiver operating characteristics (ROC) analysis and the classification using the 5th percentile as a cut-off. METHODS: One hundred eyes from 100 patients with early glaucoma (mean deviation (MD): < -5.0 dB) and 100 eyes from 100 patients with moderate/advanced glaucoma (MD: > -5.0 dB) were carefully matched to healthy controls based on optic disc size. Then, the dataset was divided, based on the 50th percentile of the measured Bruch's membrane opening area (BMO-A), into small (BMO-A < 1.95 mm2) and large optic discs (BMO-A > 1.95 mm2). Finally, the discriminative performance of BMO-MRW and RNFL between glaucoma and controls using ROC analysis and the manufacturer's classification based on the 5th percentile was analyzed. RESULTS: In discriminating between glaucoma and matched healthy controls, global BMO-MRW and global RNFL thickness had comparable areas under the ROC curve for eyes with early glaucoma and both small BMO-As (ROC ± confidence interval [CI] 0.91 [0.87 to 0.95] and 0.88 [0.83 to 0.93]) and large BMO-As (0.86 [0.82 to 0.92] and 0.84 [0.79 to 0.90]), as well as in moderate/advanced glaucoma with small BMO-As (0.99 [0.98 to 1.00] and 0.97 [0.95 to 1.00]) and large BMO-As (0.94 [0.91 to 0.98] and 0.97 [0.94 to 1.00]). Using the calculated 5th percentile as a threshold value, the sensitivities for the detection of early and moderate/advanced glaucoma were comparable for BMO-MRW and RNFL in eyes with small optic discs (early glaucoma: fifty-two percent and 61%; moderate/advanced glaucoma: ninety-one percent and 92%). In eyes with large optic discs, the sensitivity of BMO-MRW was inferior to that of RNFL for both early (38% versus 51%) and moderate/advanced (80% versus 91%) glaucoma. CONCLUSION: Based on an ROC analysis, the discriminative performance of BMO-MRW and RNFL between patients with early and moderate/advanced glaucoma and a healthy control group matched based on optic disc size is comparable in eyes with BMO-As smaller and larger 1.95 mm2. Using a classification based on the 5th percentile, as used in clinical practice, RNFL is shown to be superior to BMO-MRW regarding sensitivity in glaucoma detection with large optic discs. This study underscores the importance of RNFL imaging and measurement in the diagnostic evaluation of glaucoma, especially in cases of large optic discs.

Retrospective Analysis of Bicanalicular Lacrimal Silicone Tube Intubation in Patients with Congenital Nasolacrimal Duct Obstruction: A Long-term Follow-up Study.

Congenital nasolacrimal duct obstruction (CNLDO) is the most common cause of epiphora in the first year of life. In addition to conservative therapy, there are several invasive methods available. The aim of this retrospective study was to conduct a long-term follow-up of bicanalicular lacrimal duct intubation as the primary intervention in a large cohort of patients with CNLDO. The electronic medical records of 487 patients with CNLDO who underwent bicanalicular tube intubation were reviewed. To determine the long-term outcomes, a telephone interview was conducted. A total of 328 eyes of 235 patients were included in the study. The median average follow-up period was 6.67 (5.58 - 8.67) years. At the time of the survey, 218 patients (92.8%) were symptom free. Mean patient satisfaction with surgical outcome was 10/10. To our knowledge, this study provides the longest follow-up of the largest patient cohort in the literature consisting of patients who underwent probing with bicanalicular lacrimal silicone tube intubation as a primary intervention for CNLDO. This study showed a high long-term postoperative success rate, with high postoperative satisfaction, few complications, and a low need for reintervention.

Retinal microvascular density analysis in patients with rheumatoid arthritis treated with hydroxychloroquine.

PURPOSE: Rheumatoid arthritis (RA) is the most common inflammatory joint disease, and hydroxychloroquine (HCQ) is an established treatment. The extent to which HCQ impacts ocular microvascular vessel density (VD) in patients with RA without evidence of HCQ retinopathy has not yet been conclusively clarified. The main aim of this study was to evaluate VD measured by optical coherence tomography angiography (OCTA) in patients with RA treated with HCQ. METHODS: The VD data of the 3 × 3 mm OCT angiogram (RTVue XR Avanti, Optovue Inc., Fremont, California, USA) as well as the retinal thickness (RT) data of patients with RA (n = 30) and healthy controls (n = 30) were extracted and analyzed. The study group was further divided into patients undergoing HCQ treatment for > 5 years (high-risk-group) and < 5 years (low-risk group). RESULTS: Patients with RA showed no evidence of VD reduction compared to the control group in all obtained regions (p > 0.05). Correlation analysis revealed no dependency between VD, RT, and HCQ therapy duration or cumulative HCQ dose (p > 0.05). High-risk patients showed a decreased VD in the superficial quadrant of the superficial capillary plexus compared to low-risk-patients (p = 0.022). Whole-en-face RT was reduced in the high-risk group compared to the control group (p = 0.019). CONCLUSION: Our study showed no evidence that HCQ diminishes VD in patients with RA without HCQ retinopathy measured by OCTA. However, RA patients with a long duration of therapy showed a significantly reduced RT. Our results suggest that quantitative VD analysis by OCTA may not be suitable for early detection of HCQ retinopathy and that the focus on detecting early HCQ retinopathy should be on intensive and sequential OCT diagnostics.

FURTHER EVIDENCE AGAINST BILATERAL MANIFESTATION OF COATS DISEASE IN OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY OF THE MACULA.

PURPOSE: Recent studies have questioned the traditional view, which regards Coats disease as a strictly unilateral entity. Applying optical coherence tomography angiography, this prospective, monocentric study investigates quantitative capillary changes of the macula associated with Coats disease. METHODS: Twenty-four eyes (4 untreated, 8 pre-treated) of 12 patients with stage 2 Coats disease (age range: 9-61 years) and 15 eyes of healthy, age-matched controls from the University of Muenster Medical Center, Germany received macular optical coherence tomography angiography measurements of the superficial, deep, and choriocapillary capillary plexus. Flow density and parameters related to the foveal avascular zone were compared between Coats eyes and fellow eyes, and between fellow eyes and control eyes. Additional subanalyses investigated changes based on disease stage. RESULTS: Flow density did not differ between fellow eyes of Coats disease patients and control eyes in any of the parameters investigated. Comparison of Coats eyes to their respective fellow eyes revealed Coats disease to be associated with lower flow density in superficial, deep, and choriocapillary capillary plexus regions, irrespective of disease stage (all P < 0.03). There were no noticeable differences regarding the size or symmetry of the foveal avascular zone. CONCLUSION: In light of the recent discussion around the unilateral character of Coats disease, this trial provides evidence against a bilateral presentation of vascular changes in the macula.

Idiopathic Epiretinal Membranes - Pathophysiology, Classifications and OCT-Biomarkers. / Idiopathische epiretinale Membranen ­ Pathophysiologie, Klassifikationen und OCT-Biomarker.

Epiretinal membranes (ERMs) are a common finding in patients with increasing age. Diagnosis and treatment of ERMs have changed dramatically in recent years due to technological advances in ophthalmological care. In recent years, tomographic imaging has allowed for accurate visualization of ERMs and contributed to the growing understanding of the pathophysiology of this condition. The literature review conducted here summarizes recent innovations in diagnosis, classification, and treatment of idiopathic ERMs and specifically addresses novel optical coherence tomography (OCT) biomarkers that allow for the generation of prognoses regarding the clinical postoperative outcome.

[Effects of Susac syndrome on the central vascular structure of the retina-An optical coherence tomography angiography study]. / Auswirkungen des Susac-Syndroms auf die zentrale Gefäßstruktur der Netzhaut ­ eine optische Kohärenztomographie-Angiographie-Studie.

BACKGROUND: Susac syndrome (SS) describes an endotheliopathy of vessels in the central nervous system. Retinal involvement plays a central role in the manifestation of the disease. OBJECTIVE: This case-control study investigated the macular microvasculature in patients with chronic SS compared to controls using optical coherence tomography angiography (OCTA). MATERIAL AND METHODS: 12 eyes of 12 patients with SS were compared with age-matched healthy control subjects with regard to their OCT angiographic parameters. The flow density (FD) of different macular layers, foveal avascular zone (FAZ) parameters and central retinal thickness and volume values were compared between the two groups. RESULTS: The FD of the choriocapillaris was reduced in Susac patients compared to healthy controls. The FD values of the superficial and deep capillary plexus of the inner retina, parameters of the FAZ as well as central retinal thickness and volume showed no significant differences between the two groups. DISCUSSION: Treated chronic SS does not appear to significantly affect the vascular and structural composition of the central inner retina; however, differences in the choriocapillaris indicate changes in deeper, highly vascularized capillary layers.

Reduced Retinal Blood Vessel Densities Measured by Optical Coherence Tomography Angiography in Keratoconus Patients Are Negatively Correlated with Keratoconus Severity.

Keratoconus (KC) is the most common corneal ectasia. Optical coherence tomography angiography (OCT-A) is a relatively new non-invasive imaging technique that allows the visualization and quantification of retinal and choriocapillary blood vessels. The aim of this study is to assess retinal and choriocapillary vessel density (VD) differences between KC patients and healthy controls and to investigate correlations between VD and KC severity. Fifty-two eyes were included in this exploratory study: twenty-six eyes from 26 KC patients and twenty-six eyes from 26 age- and gender-matched healthy controls. All patients underwent Scheimpflug corneal topography with Pentacam, axis lengths measurement and optical coherence tomography angiography (OCT-A). The thinnest spot in corneal pachymetry, maximum K (Kmax) and KC severity indices from the Belin/Ambrósio enhanced ectasia display (BAD) were also assessed. There was a distinct reduction particularly in the retinal VD of the superficial capillary plexus (SCP). Correlation analyses showed strong and moderate negative correlations between the VD in the macular SCP and BAD KC scores and between the SCP VD and Kmax. There was no difference in retinal thickness between the KC and healthy controls. With this study, further evidence for altered VD measurements by OCT-A in KC patients is given. For the first time, we demonstrated negative correlations between BAD KC scores and retinal blood vessel alterations. A major limitation of the study is the relatively small sample size. Since an artefactual reduction of the quantitative OCT-A measurements due to irregular corneal topography in KC must be assumed, it remains to be investigated whether there are also actual changes in the retinal microcirculation in KC.

[Frequency and distribution of the active agent of intravitreal injections in German centers 2015-2021-An oregis study]. / Häufigkeit und Wirkstoffverteilung intravitrealer Injektionen in deutschen Zentren 2015 bis 2021 ­ eine oregis-Studie.

INTRODUCTION: Digitalization in medicine, especially the electronic documentation of patient data, is revolutionizing healthcare systems worldwide. The evaluation of real-world data collected under everyday conditions presents opportunities but also challenges. Electronic medical registries provide a means to compile extensive patient data for scientific inquiries. Oregis is the first nationwide digital registry for health services research established by the German Ophthalmological Society (DOG). Intravitreal operative medicinal injections (IVOM) are among the most frequently performed procedures in ophthalmology. Data on injection numbers and injection frequencies with anti-vascular endothelial growth factor (VEGF) are already available from other countries, whereas data at a national level are not yet available in Germany due to the lack of a nationwide register. It is known that the treatment success of anti-VEGF IVOMs depends largely on the adherence to treatment and thus on the number of injections. There are also differences in cost. In the context of this study, real-world data on the frequency and distribution of intravitreal injections in German centers from 2015 to 2021 were compiled for the first time since the introduction of oregis. The aim of this study is to collect data on the use of anti-VEGF IVOMs in Germany from oregis for the first time and to show the development of injection numbers and anti-VEGF drugs used. At the same time, the possibilities of data retrieval from oregis are demonstrated using a concrete example from daily ophthalmological practice. MATERIAL AND METHODS: An automated query of records was performed for all patients who received IVOM at oregis-affiliated healthcare facilities between 2015 and 2021. The number of treated patients and the use of anti-VEGF medications, including aflibercept, bevacizumab, brolucizumab, and ranibizumab, were determined. The data were collected in a pseudonymized and anonymized manner. RESULTS: At the time of data collection, 9 German ophthalmological healthcare facilities were affiliated with oregis. In total, 309,152 patients were registered during the observation period, with 8474 receiving IVOMs. Over the observation period, the number of participating centers, patients, and intravitreal injections increased. The proportional share of anti-VEGF agents among the total number of injections varied during the observation period. DISCUSSION: Real-world data captured in oregis offer significant potential for enhancing healthcare provision. Oregis enables the depiction of ophthalmological care conditions in Germany and contributes to research and quality assurance. The ability to query the presented data exemplifies the multitude of inquiries through which oregis can contribute to the representation of ophthalmological care in Germany.

Visualization of the Postoperative Position of the Hydrus® Microstent Using Automatic 360° Gonioscopy.

Introduction: Glaucoma, one leading cause of irreversible vision loss worldwide, is primarily caused by elevated intraocular pressure (IOP). Recently, minimally invasive glaucoma surgeries (MIGSs) have become popular due to their shorter surgical times, tissue-sparing nature, and faster recovery. One such MIGS, the Hydrus® nickel-titanium alloy Microstent, helps lower IOP by improving aqueous humor outflow. The NIDEK GS-1 automated 360° gonioscope provides advanced imaging of the chamber angle for evaluation and documentation. The aim of this study was to test automated 360° gonioscopy for the detection of postoperative positional variations after Hydrus® Microstent implantation. This study is the largest to date to evaluate post-op positioning of the Hydrus® Microstent using the NIDEK GS-1. Materials and Methods: This study analyzed postoperative outcomes and stent location in eyes diagnosed with mild to moderate glaucoma that underwent Hydrus® Microstent implantation with or without phacoemulsification. Patients with prior IOP-lowering surgery or vitrectomy were excluded. Analyses of the postoperative Hydrus® Microstent position were based on the evaluation of automated 360° gonioscopy images. Results: Twenty-three eyes were included in the study, and all showed a reduction in IOP and a decrease in antiglaucomatous drop use postoperatively. Postoperative gonoscopic images showed variations in implant position. In all cases, the proximal inlet was clearly visible in the anterior chamber. The degree of protrusion into the anterior chamber was variable. The distal tip of the stent was visible behind the trabecular meshwork in Schlemm's canal in five cases, in the anterior chamber in one case, and not visible in seven cases. In no case did postoperative alterations in the position of the implant lead to explantation. Conclusions: This study demonstrated that the Hydrus® Microstent can effectively lower IOP even in the presence of postoperative positional variations. Automated 360° gonioscopy was found to be a useful tool to verify and document the postoperative position of the implant. Positional changes did not require device explantation in any of the cases evaluated.

Microvascular Density Analysis of Patients with Inactive Systemic Lupus Erythematosus-A Two-Year Follow-Up Optical Coherence Tomography Angiography Study.

Background/Objectives: This study aims to investigate the long-term effect of inactive systemic lupus erythematosus (SLE) on the retinal microcirculation measured via optical coherence tomography angiography (OCT-A). Methods: Twenty-four eyes of 24 patients with inactive SLE under hydroxychloroquine (HCQ) therapy were included. The OCT-A data (mainly vessel density (VD) and foveal avascular zone (FAZ) data of the superficial and of the deep capillary plexus (SCP, DCP) and the choriocapillaris (CC)) were analyzed and compared between the baseline examination (t0) and 2 years later (t1). Results: At t1, VD in the whole en face SCP and in the CC was notably reduced compared to t0 (SCP: p = 0.001, CC: p = 0.013). VD in the DCP, CRT and FAZ area showed no difference at t1 compared to t0 (DCP: p = 0.128, FAZ: p = 0.332, CRT fovea: p = 0.296). Correlation analysis between the increase in cumulative doses of HCQ between t0 and t1 and the VD of the whole en face SCP did not show any correlation (Spearman r = 0.062 (95% CI -0.367; 0.477). Conclusions: SLE patients demonstrated a decrease in the retinal VD of the SCP and CC over a 2-year period. There was no correlation with the change in cumulative doses of HCQ. These results suggest an ongoing effect of the disease on the retinal and choriocapillary microcirculation.

Preserflo MicroShunt versus Trabeculectomy: Efficacy and Surgical Success within a Heterogenous Patient Cohort.

To compare success rates of trabeculectomy (TE) and Preserflo MicroShunt (PMS) in heterogenous glaucoma cohorts with regards to different pre- and postoperative therapeutic regimens. Data of 187 glaucoma patients who either received TE (73 eyes) or PMS implantation (114 eyes) between January 2018 and December 2022 were retrospectively evaluated. Surgical success and failure rates were analyzed within six months of follow-up. Intraocular pressure (IOP) development over the course of follow-up was compared between both groups. Tertiary outcome measures were best-corrected visual acuity (BCVA), number and type of medications, frequency of postoperative complications and revision surgeries. Outcome measures underwent additional assessment based on subgroup categorizations, and failure time hazard ratios were computed. The success rates were comparable between both procedures (TE: 54.1%, PMS: 60.0%; p = 0.17). Both procedures showed significant IOP reduction (p < 0.01); however, overall IOP reduction was greater in the TE group than in the PMS group (TE: Reduction by 12 mmHg (188.9%), PMS: Reduction by 7 mmHg (51.3%); p = 0.01). The number of topical medications decreased significantly in both groups over the course of follow-up (TE: 4 to 0, PMS: 3 to 0; p < 0.01). While the number of complications and revision surgeries were similar in both groups, the time interval until the first revision surgery within the TE group was significantly shorter (TE: 13.5 d, PMS: 163 d; p = 0.01) than within the PMS group. No difference could be detected between TE and PMS with regard to the follow-up regimen. In particular, there was no significant difference in the need for 5-floururacil injections postoperatively (p = 0.29). Less invasive glaucoma surgery with the PMS appeared comparable to the TE within a heterogenous glaucoma cohort with regards to IOP development and freedom from medication.

Submacular Hemorrhages Show No Significant Seasonal Variations in a European Cohort.

The aim of the article is to investigate the seasonality of acute submacular hemorrhages (SMHs) in a European population and analyze the influence of the seasons, arterial hypertension, and intake of anticoagulatory/antiplatelet (AC/AP) medication on hemorrhage size. This retrospective, monocentric study included 164 eyes of 164 patients treated for acute SMH at the University Hospital Münster, Germany, between 1 January 2016 and 31 December 2021. Data on the day of occurrence, hemorrhage size, and general patient characteristics were recorded. "Test for cyclic trends in incidence data" and the Chi-Square Test were applied to investigate seasonal variations in SMH incidence. Fisher's exact test was used to investigate the influence of the seasons, arterial hypertension, and intake of AC/AP medication on hemorrhage size. A statistical analysis did not reveal significant seasonal variations in the occurrence of SMHs (p = 0.81). While the seasons and the presence of systemic arterial hypertension did not exert a significant influence, the intake of AC/AP medication significantly affected the size of SMH (p = 0.03). In this European cohort, no significant seasonal variations of SMHs were observed. However, in patients with risk factors, such as neovascular age-related macular degeneration (nAMD), the chance of an increase in hemorrhage size should be considered when initiating AC/AP therapy.

Short-term-outcomes of idiopathic epiretinal membranes treated with pars-plana-vitrectomy - examination of visual function and OCT-morphology.

BACKGROUND: Epiretinal membranes (ERM) represent one of the most common findings in retinal examination. Structural changes of the retinal layers in patients with ERM can be visualized and classified using OCT. The purpose of this study is to evaluate structural and functional changes related to surgical treatment of ERM. METHODS: Monocentric retrospective analysis of 92 patients who underwent 23-gauge-pars plana vitrectomy (ppV) combined with cataract surgery for idiopathic ERM from 2015 to 2020. Visual acuity was determined directly preoperatively, at four weeks and three months postoperatively. Disease stage and tomographic biomarkers related to ERM were assessed in OCT imaging. RESULTS: 92 eyes of 92 patients were included. At the time of surgery, the mean patient age was 71 years. Visual acuity improved significantly by 2 lines postoperatively, on average from LogMar 0.4 to 0.2 (p < 0.001). Disease stage regressed from stage 3 to stage 2 postoperatively (p < 0.001). No patient had stage 4 postoperatively (n = 0). In the presence of preoperative intraretinal fluid, mean retinal thickness was 488 µm and decreased to 392 µm postoperatively (n = 32; p < 0.001). Preoperative presence of a Cotton Ball Sign (n = 30) was associated with better visual acuity (p = 0.009). This was also visible in patients with preoperative vitreomacular traction syndrome (p < 0.001). The presence of preoperative intraretinal fluid showed a tendency towards better disease staging after surgery (p = 0.080). CONCLUSION: Surgery was able to achieve visual improvement and morphological regression of the preoperative OCT findings related to ERM. ppV led to a reduction in retinal thickness and disease stage. The presence of the Cotton Ball Sign and vitreomacular traction was associated with better visual acuity in the follow-up period. In our cohort the preoperative presence of intraretinal fluid showed a tendency for better postoperative disease staging.

[oregis-The German ophthalmological registry]. / oregis ­ Das deutsche ophthalmologische Register.

BACKGROUND: Medical registries have shown their potential for medical research in different areas of healthcare in the past. The United States of America uses the well-known national ophthalmology registry Intelligent Research in Sight (IRIS®), on the basis of which insights into the ophthalmological care situation in the USA can be gained. Comparable projects do not currently exist in Germany. The oregis is the first disease-independent registry to collect comprehensive data in the field of ophthalmology in Germany for the purpose of healthcare research. METHODS: The oregis collects anonymized clinical patient information from all subfields of ophthalmology and makes it available for research purposes. Participating centers read their data into the registry free of charge and preferably in an automated fashion. Currently, the oregis parameter list contains about 600 parameters, of which about 100 are used in the current pilot phase. RESULTS: Since its initiation, the German ophthalmological registry oregis has compiled data on more than 1.75 million physician visits for more than 400,000 patients from German ophthalmologic centers. As of late 2022, more than 2.8 million visual acuity measurements and an equal number of intraocular pressure measurements have been recorded. DISCUSSION: The aim of the oregis project is to establish a nationwide ophthalmology databank that forms the basis for a learning healthcare system in the field of ophthalmology. With the help of continuous updating, oregis can also illustrate short-term innovations in ophthalmological care.

Blood Vessel Segmentation Using U-Net for Glaucoma Diagnosis with Limited Data.

Glaucoma is one of the leading causes of blindness worldwide. Therefore, early detection and diagnosis are key to preserve full vision in patients. As part of the SALUS study, we create a blood vessel segmentation model based on U-Net. We trained U-Net on three different loss functions and used hyperparameter tuning to find their optimal hyperparameters for each loss function. The best models for each of the loss functions achieved an accuracy of over 93%, Dice scores around 83% and Intersection over Union scores over 70%. They each identify large blood vessels reliably and even recognize smaller blood vessels in the retinal fundus images and thus pave the way for improved glaucoma management.

Descemet Membrane Endothelial Keratoplasty (DMEK) Reduces the Corneal Epithelial Thickness in Fuchs' Patients.

Fuchs' endothelial corneal dystrophy (FECD) is the occurrence of corneal edema due to endothelial cell dystrophy. Descemet membrane endothelial keratoplasty (DMEK) is considered to be the gold standard of treatment. The aim of this study was to investigate the changes in the corneal epithelial thickness of FECD patients before and after DMEK and to compare these results with a healthy control cohort. In this retrospective analysis, 38 eyes of patients with FECD that were treated with DMEK and 35 healthy control eyes received anterior segment optical coherence tomography (OCT; Optovue, XR-Avanti, Fremont, CA, USA). The corneal epithelial thicknesses in different locations were analyzed and compared between the preoperative, postoperative, and control cohorts. The median follow-up time was 9 months. There was a significant degression of the mean epithelial thickness after DMEK in the central, paracentral, and mid-peripheral zones (p < 0.01) of the cornea. The total corneal thickness and stromal thickness decreased significantly as well. No significant differences were observed between the postoperative and control cohorts. In conclusion, the FECD patients had an increased epithelial thickness compared to the healthy controls, which decreased significantly after DMEK and reached thickness levels comparable to those of healthy control eyes. This study emphasized the importance of distinguishing between the corneal layers in anterior segment pathologies and surgical procedures. Moreover, it accentuated the fact that the structural alterations in FECD extend beyond the corneal stroma.

Evaluation of Ocular Perfusion in Patients with End-Stage Renal Disease Receiving Hemodialysis Using Optical Coherence Tomography Angiography.

Hemodialysis (HD) is known to affect ocular blood flow. This case-control study aims to evaluate macular and peripapillary vasculature in patients with end-stage renal disease (ESRD) receiving HD in comparison to matched controls. A total of 24 eyes of 24 ESRD patients receiving HD and 24 eyes of 24 healthy, age- and gender-matched control subjects were prospectively included in this study. Optical coherence tomography angiography was used to image the superficial (SCP), deep (DCP), and choriocapillary (CC) macular vascular plexus, as well as the radial peripapillary capillaries (RPC) of the optic disc. In addition, retinal thickness (RT) and retinal volume (RV) were compared between both groups. Flow density (FD) values of each retinal layer and data of parameters related to the foveal avascular zone (FAZ), as well as RT and RV, were analyzed using Mann-Whitney U tests. There was no significant difference in FAZ parameters between the two groups. Whole en face FD of the SCP and CC was noticeably reduced in the HD group in comparison to the control group. FD was negatively correlated with the duration of HD treatment. RT and RV were significantly smaller in the study group than in controls. Retinal microcirculation appears altered in patients with ESRD undergoing HD. Concurrently, the DCP appears more resilient towards hemodynamic changes in comparison to the other microvascular retinal layers. OCTA is a useful, non-invasive tool to investigate retinal microcirculation in ESRD patients.

Position of the ISTENT Inject® Trabecular Micro-Bypass System Visualized with the NIDEK GS-1 Gonioscope-A Postoperative Analysis.

Glaucoma is one of the leading causes of irreversible blindness globally and is characterized by the gradual loss of retinal ganglion cells. The primary risk factor for the development and progression of glaucoma is increased intraocular pressure (IOP). Numerous surgical interventions exist to lower IOP should conservative therapy fail. One trend in recent years has been minimally invasive glaucoma surgery (MIGS) as an alternative to traditional methods. The ISTENT inject® is an ab interno trabecular micro-bypass implant designed to be implanted through the trabecular meshwork into the Schlemm's canal to lower IOP. The aim of the study was the postoperative visualization and description of the positioning of the ISTENT inject® using automated circumferential goniophotography. Patients with symptomatic cataracts and mild to moderate primary open-angle glaucoma (POAG), pseudoexfoliation glaucoma (PEX), and pigment-dispersion glaucoma were included who underwent combined cataract surgery with the ISTENT inject® and received postoperative automated gonioscopy with the NIDEK Gonioscope GS-1 to visualize the location of the implant. Twenty-four implants of 14 eyes in 11 patients could be visualized. Out of the implants, 14.3% were in the trabecular meshwork, 46.4% were at the border between the trabecular meshwork and scleral spur, 25% were below the trabecular meshwork, and 14.3% of the implants were not detectable in the gonioscopy. In the overall cohort, a statistically significant IOP reduction was found over the 12-month postoperative observation period. Even in three eyes, in each of which both stents were located below the trabecular meshwork, an IOP reduction over 12 months was observed compared to the baseline IOP. In this study, vertical two-dimensional positioning of the ISTENT inject® was performed for the first time using NIDKE GS-1 automated 360° goniophotography. The method is suitable for postoperative visualization, control, and documentation of positioning after ISTENT inject® implantation. Further studies are needed to analyze the correlation between positioning of the ISTENT inject® in the chamber angle and postoperative IOP reduction.

Characterizing Foveal Hypoplasia Using Optical Coherence Tomography Angiography: Evaluation of Microvascular Abnormalities and Clinical Significance.

This study aimed to evaluate foveal avascular zone (FAZ) features and macular flow density (FD) in various retinal layers in a cohort of patients with foveal hypoplasia (FH) using optical coherence tomography angiography (OCTA), in order to characterize microvascular abnormalities and explore their potential clinical significance. FAZ parameters and FD, as well as retinal thickness and volume values were analyzed and compared between patients with FH and an age- and gender-matched control cohort. Correlations between disease severity and visual acuity (VA), as well as between disease severity and FAZ features were evaluated. A total of 19 eyes with FH and 19 control eyes were included. The study group showed significantly higher FD values in the foveal sectors of the superficial and deep capillary plexus compared to controls. FAZ area, perimeter, and acircularity index (ACI) were noticeably altered in eyes with FH; however, they did not correlate with disease severity. Visual acuity was negatively correlated with disease severity. The results of this study provide evidence of altered microvasculature architecture specifically in the foveal sectors of patients with FH. The higher FD values in the foveal sectors of FH patients suggest a potential compensatory response of the retinal microvasculature. FAZ parameters and FD values of the foveal sectors could be used as part of an OCTA-based grading system in FH patients.