Experimental glaucoma microstent implantation in two animal models and human donor eyes-an micro-computed tomography-based evaluation of applicability.

Background: Minimally invasive glaucoma surgery (MIGS) has become an important treatment approach for primary open angle glaucoma. Restoration of aqueous humour drainage by means of alloplastic implants represents a promising treatment option and is itself subject of methodological development. An adequate positioning in the targeted tissue regions is essential is important for the performance of our in-house developed Rostock glaucoma microstent (RGM).

γ-Cyclodextrin hydrogel for the sustained release of josamycin for potential ocular application.

Glaucoma is the leading cause of blindness worldwide. However, its surgical treatment, in particular via trabeculectomy, can be complicated by fibrosis. In current clinical practice, application of the drug, Mitomycin C, prevents or delays fibrosis, but can lead to additional side effects, such as bleb leakage and hypotony.

Ex Vivo Micro-CT in Ophthalmology: Preparation and Contrasting for Non-invasive 3D-Visualisation.

X-ray-based micro-computed tomography (micro-CT) is a largely non-destructive imaging method for the visualisation and analysis of internal structures in the ex vivo eye and affords high resolution. In contrast to other high-resolution imaging methods, micro-CT enables spatial recording of larger and more complex tissue structures, such as the anterior chamber of the eye. Special contrasting methods help to enhance the absorption properties of soft tissue, that is otherwise only weakly radiopaque.

Effects of prenatal Doppler ultrasound on the retina of the chick embryo in ovo.

Currently, the effect of prenatal ultrasound on foetal development is intensively discussed and the guidelines for prenatal diagnostics have been changed. However, data supporting these concerns are scarce. Therefore, we used an established in ovo model of the chicken embryo to investigate cell proliferation and apoptosis within the retina.

Development of a Novel Valve-Controlled Drug-Elutable Microstent for Microinvasive Glaucoma Surgery: In Vitro and Preclinical In Vivo Studies.

Purpose: Microinvasive glaucoma surgery (MIGS) has become an important treatment approach for primary open-angle glaucoma, although the safe and long-term effective lowering of intraocular pressure with currently available implants for MIGS is not yet achieved to a satisfactory extent. The study focusses on the development and in vitro and in vivo testing of a novel microstent for MIGS.

Methods: A silicone elastomer-based microstent was developed.

The Antibiotic Kitasamycin-A Potential Agent for Specific Fibrosis Preventing Therapy after Fistulating Glaucoma Surgery?

One major complication after fistulating glaucoma surgeries are fibroblast-mediated scarring processes and their specific prevention is key in the development of novel pharmaceutical concepts. Within this study a possible antifibrotic potential of kitasamycin (KM) in a transforming growth factor (TGF)-β1-mediated fibroblast model was evaluated . Primary ocular fibroblasts were isolated, cultivated and a dose-response test including determination of the half maximal effective concentration (EC50) for KM was conducted.

Quantitative systems pharmacology of the eye: Tools and data for ocular QSP.

Good eyesight belongs to the most-valued attributes of health, and diseases of the eye are a significant healthcare burden. Case numbers are expected to further increase in the next decades due to an aging society. The development of drugs in ophthalmology, however, is difficult due to limited accessibility of the eye, in terms of drug administration and in terms of sampling of tissues for drug pharmacokinetics (PKs) and pharmacodynamics (PDs).

MR microscopy of the developing upper extremity of the chicken in ovo using 7 Tesla MRI.

MR microscopy (MRM) is known as ultra-high-field (UHF) magnetic resonance imaging with an in-plane spatial resolution of <100 μm, yields highly resolved non-invasive anatomical imaging and allows longitudinal assessment of embryonic avian development. The aim of the present study was to evaluate the feasibility of in vivo anatomical MRI assessment of the developing upper extremity of the chicken. Thirty-eight fertilized chicken eggs were examined at 7 Tesla acquiring high-resolution T2-weighted images with an in-plane resolution of 74 × 74 μm.

Micro-CT in ophthalmology: preparation and contrasting methods for detailed 3D-visualization of eye anatomy with special emphasis on critical point drying.

Background: Micro-computed tomography (micro-CT) provides detailed 3-dimensional (3D) visualization of anatomical structures and encourages morphological reinvestigation of organs with delicate features. The low radiodensity of soft tissues necessitates preceding sample preparation to conduct X-ray imaging with decent contrast between different tissues. In this study, we demonstrate the preparation with three radiopaque agents in combination with elimination of liquids by critical point drying (CPD) introduced for ocular samples.

Ophthalmic Ultrasonography in Sub-Saharan Africa-A Kinshasa Experience.

The aim of this study was to analyze the use of the diagnostic B-scan ultrasound. Should it be made accessible to all surgical centers in Sub-Saharan Africa in order to (i) avoid unnecessary cataract surgery and (ii) evaluate extraocular pathology? This study was conducted in Kinshasa from 2006 to 2019. Three hundred and twenty-three patients were included and separated into two groups.

Predictive value of retinal function by the Purkinje test in patients scheduled for cataract surgery in Kinshasa, DR Congo.

Aim: To assess the retinal function in patients with dense cataracts in resource poor settings in Kinshasa, DR Congo.

Methods: In a tertiary eye care center, the Purkinje entoptic test was performed as part of the ophthalmological examination in 98 eyes in patients with cataract, using a penlight. Totally 92 cataract patients including 86 patients suffered from unilateral and 6 from bilateral cataracts were included in the study.

Bilateral paediatric cataract surgery - outcomes of 298 children from Kinshasa, the Democratic Republic of the Congo.

Introduction: The leading cause of childhood blindness globally is paediatric cataract. Bilateral cataract surgery can help to improve visual performance and to diminish the burden of childhood blindness.

Objective: To report in a retrospective observational cohort study the long-term outcomes of 298 children who had bilateral cataract surgery with IOL implantation from 2001-2016 in Kinshasa.

Ultrahigh field MRI determination of water diffusion rates in human lenses of different age.

Background: The development of presbyopia is correlated with increased lens stiffness. To reveal structural changes with age, ultrahigh field magnetic resonance imaging (UHF-MRI) was used to analyze water diffusion in differently aged human lenses .

Methods: After enucleation lens extractions were performed.

Prevalence and patterns of childhood ocular morbidity in Kinshasa. A population-based study.

Context: Childhood ocular disorders can seriously impact on development and education, future employment opportunities and quality of life, their consequences are especially severe in low resource settings. There is a lack of data on pattern and prevalence of ocular morbidities among children in Democratic Republic of the Congo (DRC).

Objective: The aim of this study was to determine the pattern and magnitude of childhood ocular disorders in children in Kinshasa, the capital city of DRC.

Morphological characterization of the human corneal epithelium by confocal laser scanning microscopy.

Background: Regarding the growing interest and importance of understanding the cellular changes of the cornea in diseases, a quantitative cellular characterization of the epithelium is becoming increasingly important. Towards this, the latest research offers considerable improvements in imaging of the cornea by confocal laser scanning microscopy (CLSM). This study presents a pipeline to generate normative morphological data of epithelial cell layers of healthy human corneas.

Atypical Cellular Elements of Unknown Origin in the Subbasal Nerve Plexus of a Diabetic Cornea Diagnosed by Large-Area Confocal Laser Scanning Microscopy.

In vivo large-area confocal laser scanning microscopy (CLSM) of the human eye using EyeGuidance technology allows a large-scale morphometric assessment of the corneal subbasal nerve plexus (SNP). Here, the SNP of a patient suffering from diabetes and associated late complications was analyzed. The SNP contained multiple clusters of large hyperintense, stellate-shaped, cellular-like structures.

Age-Related Changes of the Human Crystalline Lens on High-Spatial Resolution Three-Dimensional T1-Weighted Brain Magnetic Resonance Images In Vivo.

Purpose: To reveal age-related changes of the human crystalline lens by using high-spatial resolution T1-weighted brain magnetic resonance imaging of patients under general anesthesia.

Methods: We retrospectively identified 47 children (2-17 years) and 30 adults (18-70 years) without diabetes or eye disease, who required brain magnetic resonance imaging examinations under general anesthesia between 2012 and 2019. Normalized signal intensity of the crystalline lens and vitreous body, as well as equatorial diameter and axial thickness of the lens were assessed by using a three-dimensional T1-weighted magnetization prepared rapid acquisition gradient echo sequence of the brain with 0.

In vivo Histology of the Cornea - from the "Rostock Cornea Module" to the "Rostock Electronic Slit Lamp" - a Clinical "Proof of Concept" Study.

Introduction: Confocal in vivo microscopy is an established method in ophthalmology research. As it requires contact coupling and calibration of the instruments is suboptimal, this method has been only rarely used in clinical routine work. As a result of close collaboration between physicists, information scientists and ophthalmologists, confocal laser scanning microscopy (CLSM) of the eye has been developed in recent years and a prototype can now be used in patients.

Multiwavelength confocal laser scanning microscopy of the cornea.

Confocal reflectance microscopy has demonstrated the ability to produce images of corneal tissue with sufficient cellular resolution to diagnose a broad range of corneal conditions. To investigate the spectral behavior of corneal reflectance imaging, a modified laser ophthalmoscope was used. Imaging was performed on a human cornea as well as on porcine and lamb corneae.

Suppression of the TGF-β pathway by a macrolide antibiotic decreases fibrotic responses by ocular fibroblasts .

To elucidate and to inhibit post-surgical fibrotic processes after trabeculectomy in glaucoma therapy, we measured gene expression in a fibrotic cell culture model, based on transforming growth factor TGF-β induction in primary human tenon fibroblasts (hTFs), and used Connectivity Map (CMap) data for drug repositioning. We found that specific molecular mechanisms behind fibrosis are the upregulation of actins, the downregulation of CD34, and the upregulation of inflammatory cytokines such as IL6, IL11 and BMP6 The macrolide antibiotic Josamycin (JM) reverses these molecular mechanisms according to data from the CMap, and we thus tested JM as an inhibitor of fibrosis. JM was first tested for its toxic effects on hTFs, where it showed no influence on cell viability, but inhibited hTF proliferation in a concentration-dependent manner.

Non-invasive detection of corneal sub-basal nerve plexus changes in multiple myeloma patients by confocal laser scanning microscopy.

Purpose: Confocal laser scanning microscopy (CLSM) is a non-invasive technique for cellular in vivo imaging of the human cornea. CLSM screening was evaluated for early detection of corneal nerve morphology changes and neuropathogenic events in different stage multiple myeloma (MM) patients. As MM patients show disease as well as therapy-related neuropathological symptoms, CLSM potentially provides a tool for non-invasive early detection of neuropathogenic events.

Assessment of the Efficacy of Microinvasive Glaucoma Surgery Techniques using an Oculopression Stress Test.

Background: Glaucoma is one of the most common causes of blindness worldwide. The only evidence-based treatment to slow down the progression of glaucoma is the reduction of intraocular pressure (IOP) using local medication or through surgery. During the last years, a large number of microinvasive glaucoma surgery techniques (MIGS) has been developed, in order to reduce the IOP in glaucoma patients safely and effectively.

Cataract surgery in Kinshasa-Is there a place for "Monovision"?

Objectives: Monovision is a method of correcting presbyopia where one eye is focused for far and the other for near vision. It is a simple, cost-effective approach to overcome the loss of accommodation with age and to become spectacles independent.

Methodology: About 50 patients, where bilateral cataract extraction was indicated, were included in this study performed at the St.