Current Status and Future Perspectives of Optic Nerve Imaging in Glaucoma.

Being the primary site of degeneration, the optic nerve has always been the focus of structural glaucoma assessment. The technical advancements, mainly of optical coherence tomography (OCT), now allow for a very precise quantification of the optic nerve head and peripapillary retina morphology. By far the most commonly used structural optic nerve parameter is the thickness of the parapapillary retinal nerve fiber, which has great clinical utility but also suffers from significant limitations, mainly in advanced glaucoma. Emerging novel imaging technologies, such as OCT angiography, polarization-sensitive or visible-light OCT and adaptive optics, offer new biomarkers that have the potential to significantly improve structural glaucoma diagnostics. Another great potential lies in the processing of the data already available. Artificial intelligence does not only help increase the reliability of current biomarkers but can also integrate data from various imaging modalities and other clinical measures to increase diagnostic accuracy. And it can, in a more efficient way, draw information from available datasets, such as an OCT scan, compared to the current concept of biomarkers, which only use a fraction of the whole dataset.

[Digital teaching 2020: Online teaching receives a better assessment than face-to-face teaching]. / Digitale Lehre 2020: Online-Unterricht erhält bessere Bewertung als Präsenzunterricht.

BACKGROUND: Due to the corona pandemic, face-to-face teaching was no longer permitted in the summer semester 2020 and online alternatives were quickly found. OBJECTIVE: In our article, we illustrate the switch from face-to-face to online teaching in ophthalmology at the University of Lübeck and compare online teaching with face-to-face teaching. METHODS: The central teaching evaluation takes place every semester with a standardized questionnaire. Based on the evaluation of these questions, a direct comparison of the attendance semester of the winter semester 2019/2020 with the online semester of the summer semester 2020 was carried out. RESULTS: The structure (p = 0.003), the organization (p = 0.001), the resources made available (p = 0.034), the attendance of the lectures (p < 0.001) and further dates (p = 0.041), the increase in interest (p = 0.039) and learning (p = 0.001) were rated better in the online semester than in the face-to-face semester. Overall, the digital summer semester 2020 (p < 0.01) received a significantly better overall grade than the face-to-face semester in winter 2019/2020. CONCLUSION: The structure of our courses has also been proven online. The theoretical content could be excellently mediated; however, practical exercises are not possible online. For the learning of practical skills, face-to-face instruction is still necessary.

Elevated endothelin-1 levels as risk factor for an impaired ocular blood flow measured by OCT-A in glaucoma.

The purpose of this study was to ascertain whether a correlation exists between glaucoma-associated alteration of ocular vascular haemodynamics and endothelin-1 (ET-1) levels exist. Eyes of patients with cataract (n = 30) or glaucoma (n = 68) were examined with optical coherence tomography (OCT) and OCT-angiography (OCT-A; AngioVue™-RTVue-XR; Optovue, Fremont, California, USA). The peripapillary and the macular vessel density (VD) values were measured. Inferior and superior retinal nerve fibre layer (RNFL) thickness loss was used for further OCT staging. Aqueous humour of the examined eye and plasma were sampled during cataract or glaucoma surgery and analysed by means of ELISA to determine their ET-1 level. Glaucoma eyes are characterised by reductions in RNFL thickness and VD that correlate significantly with the OCT GSS score. Peripheral and ocular ET-1 level were significantly elevated in patients with glaucoma and correlate positively with the OCT-GSS score of the entire study population. Peripapillary and macula VD of glaucoma patients correlates negatively with plasma ET-1 levels. Multivariable analysis showed a subordinate role of intraocular pressure predictive factor for impaired retinal blood flow compared with plasma ET-1 level in glaucoma. Peripheral ET-1 level serves as risk factor for detection of ocular blood flow changes in the optic nerve head region of glaucomatous eyes.

Microvascular and Morphologic Changes of the Macula over Lifetime.

In ocular, neurologic, and cardiovascular diseases, macular segmentation data from spectral-domain optical coherence tomography (SD-OCT) provide morphologic, and OCT-angiography (OCTA) results give microvascular information about the macula. Age was shown to influence both methods' measurements. To further characterize this association, macular SD-OCT and OCTA changes were investigated in a population of juvenile, adult, and older individuals. Macular segment thickness and superficial (SCP) and deep plexus (DCP) vascular density (VD) of 157 healthy individuals aged 10-79 years were analyzed retrospectively. One-way analysis of variance (ANOVA) was used to compare age groups. The association between macular segmentation and OCTA parameters and between these and age was evaluated using linear regression. ANOVA and linear regression analysis showed a thickness decrease in the whole macular and in the ganglion cell and inner plexiform layers with age. While the foveal avascular zone area remained constant between age groups, VD of the SCP and DCP also decreased with age. In multiple linear regression, SCP and DCP VD were associated with inner macular segment thickness in an age-independent way. To conclude, the age-related microvascular and morphological changes in the macula described in this study can contribute to improving the understanding of macular aging processes and better interpreting OCT(A) results in healthy individuals and patients suffering from various retinal diseases.

[Digital teaching 2020: students assess attention during an online lecture as equivalent to a face-to-face lecture]. / Digitale Lehre 2020: Studenten schätzen die Aufmerksamkeit während einer Onlinevorlesung gleichwertig zu einer Präsenzvorlesung ein.

BACKGROUND: The corona pandemic has led to short-term adjustments of the procedures in medical courses. In many departments classroom teaching was no longer possible so that it was necessary to implement digital courses to provide an adequate medical training. METHODS: We developed a digital curriculum based on the contents of our established courses using primary in-house tools, such as Cisco WebEx and Moodle. We then performed a student survey to evaluate the implementation of the concept. RESULTS: The evaluation showed good ratings according to teaching content and didactics. The communication with the students and between each other was also considered good. Students assessed attention during the course to be equivalent in comparison to classroom teaching. As expected, the training of practical skills was evaluated as poor. For future courses most of the students could imagine a combination of digital and classroom teaching. DISCUSSION: Implementing a digital course was a sudden challenge for students and tutors. With suitable software solutions and good communication, it is possible to adequately teach theoretical content via digital courses. Students assessed the digital training in most parts to be a good and an equivalent option compared to classroom teaching. A remaining problem is the lack of practical training.

Quantitative Comparison of the Vascular Structure of Macular Neovascularizations Between Swept-Source and Spectral-Domain Optical Coherence Tomography Angiography.

PURPOSE: The aim of this study was to ascertain and quantify the differences between swept-source (SS) and spectral-domain (SD) optical coherence tomography angiography (OCTA) imaging of macular neovascularizations (MNV) in neovascular age-related macular degeneration (nAMD). PATIENTS AND METHODS: SD-OCTA (RTVue Avanti) and SS-OCTA (PLEX® Elite 9000) were performed in 37 patients with MNV in nAMD. The MNV was delineated and the data were processed via ImageJ. The parameters MNV area, nodes per area, fractal dimension (FD), and flow density were analyzed using MatLab. RESULTS: There was close agreement between the two devices regarding MNV area (ICCc 0.977, ICCa 0.977, R2 0.977), but only slight agreement regarding nodes per area (ICCa 0.008, ICCc 0.548, R2 0.51), FD (ICCa 0.425, ICCc 0.846, R2 0.96), and flow density (ICCa 0.451, ICCc 0.656, R2 0.65). The difference between the two devices was insignificant for MNV area (type 1: p=0.328; type 2: p=0.426; type 3: p=0.615), but significant for nodes per area (type 1: p=0.002; type 2: p=0.00001; type 3: p=0.003), FD (type 1: p<0.00001; type 2: p<0.00001; type 3: p=0.015) and flow density (type 1: p=0.0004; type 2: p=0.004; type 3: p=0.052). CONCLUSION: MNV area is closely comparable between devices using SS-OCTA and SD-OCTA imaging. However, the two methods differ significantly in their precise assessment of the vascular morphology (FD, flow density, nodes per area). Therefore, results obtained using different devices are not comparable and should not be amalgamated in clinical trials.

[Does the Foveal Avascular Zone Change in Glaucoma?] / Verändert sich die foveale avaskuläre Zone beim Glaukom?

BACKGROUND: The foveal avascular zone (FAZ) - with perimeter and acircularity index (AI) and surrounding vessel density - are measured in glaucomatous eyes in comparison to healthy eyes - with additional subdivision into visual field defects in different locations (central vs. peripheral). MATERIALS AND METHODS: The data from 128 eyes were evaluated. Firstly, glaucomatous eyes (n = 74) were compared with healthy eyes (n = 54). In addition, glaucomatous eyes with a central visual field defect (ZGD, n = 19) and eyes with peripheral visual field defect (PGD, n = 34) were differentiated. The FAZ area, its perimeter and roundness, as well as the parafoveal vessel density (VD), were calculated by means of optical coherence tomography angiography in the superficial and deep vascular plexus. RESULTS: Glaucomatous eyes have no significant change in FAZ, its perimeter or the AI compared to healthy eyes. However, dividing the glaucomatous eye by visual field defect reveals that the eyes with a central defect have a significantly larger FAZ than those with a peripheral defect and the perimeter is also significantly larger. The AI shows no significant difference depending on the localisation of visual field defects. The macular/foveal VD is significantly lower in the ZDG group. CONCLUSIONS: In glaucoma, the FAZ enlarges when the visual field defect is centralised and VD decreases significantly in the area of fovea.

[Trabeculectomy with Collagen Matrix Implant as Bevacizumab Depot: Clinical Results on Efficacy and Safety]. / Trabekulektomie mit Kollagen-Matrix-Implantat als Bevacizumabdepot: klinische Ergebnisse zur Effektivität und Sicherheit.

BACKGROUND: Trabeculectomy for the surgical reduction of internal eye pressure is an established procedure, but the principle limitations are in postoperative wound healing. Various antimetabolites are regularly used to avoid postoperative subconjunctival scarring. The present study investigates whether the combination of an Ologen implant with bevacizumab can modify the rates of success and/or complications during trabeculectomy. METHODS: Three different groups of patients were evaluated in which trabeculectomy was performed with mitomycin C, either alone (group 1) or in combination with an Ologen implant (group 2) or with an Ologen implant with bevacizumab (group 3). The success and failure rates, changes in tension, postoperative complications and postoperative revision for pressure regulation were evaluated. The follow-up was 12 months for all eyes. RESULTS: A total of 130 eyes in 130 patients (mean age 67.74 ± 12.16 years). The number of substances applied preoperatively to reduce intraocular pressure was 2.89 ± 0.98 and the internal ocular pressure was 21.74 ± 5.49 mmHg. Twelve months postoperatively; the mean pressure was 13.14 ± 3.71 mmHg. The greatest absolute success rate (= IOD ≤ 15 mmHg without antiglaucoma medication) was in the group with exclusive goniotrepanation + mitomycin C (MMC; 72.5%), followed by the groups with Ologen (67.5%) and Ologen + bevacizumab (63.6%). The greatest failure rate (= IOD > 15 mmHg) was in the Ologen bevacizumab group (17.3%), followed by the pure Ologen group with 22.5% and the pure trabeculectomy group (12.3%). There were no significant differences in the success and failure rates. There were no serious intra- or postoperative complications in any group. The number of patients for whom it was necessary to loosen the traction thread was significantly lower in the sole Ologen group (p = 0.02). There were also no significant differences between the groups with respect to revisions. CONCLUSION: Using Ologen as drug depot for bevacizumab in a trabeculectomy (TE) with MMC is a safe and active surgical method without an increased risk of complications in comparison to pure TE with MMC or TE with MMC and Ologen implant. After 12 months, this treatment exhibited no significant advantages.

[Hand, foot and mouth disease-associated maculopathy: a 2-year course]. / Hand-Fuß-Mund-Krankheit-assoziierte Makulopathie: ein 2­Jahres-Verlauf.

This article reports the case of a 35-year-old male patient with acute hand, foot and mouth disease and unilateral viral maculopathy of the right eye. In the course of 2 years an improvement of the subjective symptoms with a corresponding decrease of the findings in multimodal imaging could be observed. This case report demonstrates that acute maculopathy associated with hand, foot and mouth disease is a rare but relevant differential diagnosis with mostly good regression of symptoms and findings.

Vessel density in OCT angiography permits differentiation between normal and glaucomatous optic nerve heads.

AIM: To evaluate whether optical coherence tomography angiography (OCTA) can detect altered vessel density (VD) at the optic nerve head (ONH) in glaucoma patients. Special attention is paid to the accuracy of the OCTA technique for distinguishing healthy from glaucomatous eyes. METHODS: A total of 171 eyes were examined by the OCTA system AngioVue™ (Optovue): 97 eyes diagnosed with glaucoma and 74 healthy control eyes. The papillary and peripapillary VD was measured. Furthermore, the VD was correlated with different structural and functional measurements. In order to test the accuracy of differentiation between eyes with and without glaucoma, we calculated the receiver operating characteristic curve (ROC) and the area under the curve (AUC). RESULTS: The papillary and peripapillary VD in glaucomatous eyes was significantly lower than in healthy eyes (P<0.05). The VD of the nasal peripapillary sector was significantly lower than in the other sectors. The further the disease had progressed [measured by determining the thickness of the ganglion cell complex (GCC) and the retinal nerve fiber layer (RNFL)] the greater the VD reduction. The AUC discriminated well between glaucomatous and normal eyes (consensus classifier 94.2%). CONCLUSION: OCTA allows non-invasive quantification of the peripapillary and papillary VD, which is significantly reduced in glaucomatous eyes and accurately distinguishes between healthy and diseased eyes. OCTA expands the spectrum of procedures for detecting and monitoring glaucoma.

[Uveitic Secondary Glaucoma]. / Sekundärglaukom bei Uveitis.

An intraocular pressure increase with development of glaucomatous damage is a common complication of uveitis. The prevalence has a wide range depending on various factors such as the underlying uveitis type and the duration of the disease. Pathogenetically, a distinction must be made between a secondary angle closure component and the more frequently occurring open-angle glaucoma. In diagnostics, in addition to the clinical optic nerve head assessment, perimetry and tonometry, the use of imaging examination equipment, such as OCT and HRT, are recommended. In the context of uveitic glaucoma, it must be considered in the evaluation, because the glaucoma-typical changes are generally less pronounced or can be concealed by retinal swelling in comparison with other forms of glaucoma. Therapeutically, drug therapy in the form of eye drops continues to be a first-line recommendation, with the use of topical carbonic anhydrase inhibitors or beta-blockers primarily preferred, depending on the contraindications. An operative therapy follows after unsuccessful or inadequate conservative therapy: the adequate surgical technique depends on the respective finding and includes actually techniques such as filtering procedures and glaucoma drainage devices.

Canaloplasty in patients with uveitic glaucoma: a pilot study.

PURPOSE: Glaucoma is a common vision-threatening complication of uveitis. We investigated the outcome of canaloplasty in patients with chronic uveitis and uncontrolled secondary glaucoma. METHODS: This was a retrospective study of 12 patients with medically uncontrolled secondary glaucoma who underwent canaloplasty (14 treated eyes), with follow-up of ≥ 24 months. The primary outcome measure was complete and qualified (requirement for anti-glaucomatous medication) surgical success rates, as determined by a reduction in intraocular pressure (IOP) and the need for anti-glaucomatous medication. Secondary outcome measures were uveitis activity, best-corrected visual acuity (BCVA), vision-threatening complications, and secondary glaucoma surgery. RESULTS: Canaloplasty resulted in a significant IOP reduction, from a mean preoperative baseline level of 27.1 ± 12.3 mmHg to a mean of 14.5 ± 4.3 mmHg (p = 0.01) at 24 months. Complete success (limit of 15 mmHg) was achieved in six patients and qualified success in one patient. However, failure was noted in five patients, two of whom required additional glaucoma surgery. Topical anti-glaucomatous medications were reduced from 2.7 ± 1.2 (mean ± SD) at baseline to 0.6 ± 1.2 at 24 months (p = 0.007). Uveitis activity did not increase after surgery. BCVA was not reduced; cataract progressed in two patients. CONCLUSION: At 2-year follow-up, overall success rate was 58 % (IOP ≤ 15 with or without medication), and surgery failed in 5 eyes, 2 eyes requiring additional glaucoma surgery. No harmful complications or worsening of uveitis activity were noted.