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Glaucoma represents a group of eye disorders partly related to raised intraocular pressure (IOP) leading to progressive optic nerve damage resulting in impaired vision and possibly blindness. To assess the suitability of new IOP lowering therapeutic strategies, such as the implantation of glaucoma drainage devices, appropriate animal models have to be used. Currently, a number of rodent glaucoma models are available [1], however, especially for surgical interventions rodent eyes are too small. Rabbits are much more suitable with respect to dimension. Unfortunately, rabbit glaucoma model systems described in literature are difficult to reproduce or fail totally, associated with a high level of discomfort and pain for treated animals. Therefore, development of an in vivo rabbit glaucoma model is one of the most important goals in glaucoma research. Here, we describe the adaptation of the oculopressure tonometry, an existing method to quantify the outflow of aqueous humor in humans, to generate a transient glaucoma model in rabbits. The existing suction-cup oculopressor (SCOP) is extended with newly designed suction-cups, which are adjusted to the anatomy of the rabbit eye. The modification of the oculopressure tonometry method facilitates an increase in IOP over a time frame of 9 minutes by vacuum induced deformation of the rabbit eye. This method can be used to test functionality of fistulating glaucoma surgeries or implanted drainage devices in a long term follow-up without any side effects and suffering of the animals.

Antifibrotic treatment during glaucoma surgery leads to an improved outcome for patients. Drug delivery systems for placement under the subconjuctiva after surgery made of cyclodextrins and crosslinked with Epichlorohydin were loaded with Josamycin and tested in vivo. After subconjunctival application in three New Zealand White rabbits, blood samples were taken by the means of Mitra devices at defined time points. Determination of blood levels of Josamycin was performed using liquid chromatography mass spectrometry. Detection of Josamycin was achieved during 48 h suggesting a sustained release over the course of this study.

With the PRIS-Tool we aim to enable a fast, simple and stable eye self-screening that makes pathological changes in the retinal blood vessels visible to the patient. Furthermore, we envision its application as a quick retinal function test prior to cataract surgeries in low-income regions of the world. Our pocket-sized PRIS-Tool allows for a simplified entoptic testing, due to its integrated light stimulation. PRIS stands for Purkinje Retinal Image Stabilizer. So far, we have built 12 devices in small series and distributed them in our PRIS clinical research network to discuss potential clinical applications. An assisting app will support patients in performing a reliable self-diagnosis and documenting the progress of the disease. Future work will focus on app development and the initiation and evaluation of user studies.

Fallopian tube occlusions represent one of the most common causes of female sterility. As an innovative treatment approach for affected persons, we previously presented the concept of a novel polymeric, self-expanding, and bioresorbable microstent. As a basis for microstent development, knowledge of the mechanical properties of the anatomical target structure represents a crucial requirement. The current work describes a methodological approach for the experimental determination of radial Fallopian tube compliance using optical coherence tomography. It could be shown that a quantitative assessment of the mechanical properties of porcine Fallopian tube samples - as a whole anatomical structure including the Tunica mucosa, the Tunica muscularis, and the Tunica serosa - is possible, using the described test setup. Future investigations on human samples will allow for valuable information regarding the structural-mechanical properties of the Fallopian tube. Therefore, the current work offers perspectives for the development of a novel gynecological microstent for the treatment of Fallopian tube occlusions.

Elevated intraocular pressure is the main risk factor for glaucoma and its adjustment to physiological levels can prevent progression of the disease. If conventional drop-based glaucoma therapy fails, surgical interventions such as trabeculectomy or the application of implants, which drain aqueous humour from the eye and thus reduce intraocular pressure, are used as final therapeutic procedures. These interventions are becoming increasingly minimally invasive and the drainage implants are getting steadily smaller, which is why these interventions are now called microinvasive glaucoma surgery (MIGS). Both, surgery and drainage implant-based glaucoma therapy are limited by wound healing processes and fibrosis that occlude the newly created drainage pathways for the aqueous humour. To suppress unwanted postoperative fibrosis coupled with an increased extracellular matrix production, cytostatics like mitomycin c or 5- fluorouracil are currently used, which are associated with side effects. Therefore, more specific antifibrotic agents are key for a durable functionality of the interventions in glaucoma therapy. In this study a specific active substance (pirfenidone, PFD) was added in a polymer matrix for controlled release. Previous studies have shown that the release of pirfenidone from a thermoplastic silicone polycarbonate elastomer, which could be used as a material for a glaucoma drainage implant, has been relatively fast. To decelerate the release the influence of the alternate polymers Poly-L-Lactide (PLLA) and Poly-D,LLactide (PDLLA) as alternative drug carriers was investigated. Furthermore, a reduction of the pirfenidone content was used to delay the release.

A diagnostic medical tool is described that allows patients to non-invasively observe, describe and document their own retinal blood vessels using the Purkinje vascular entoptic test. We envision key applications of the Purkinje retinal image stabilization (PRIS) device in monitoring of diabetic retinopathy and cost-effective assessment of retinal visual acuity. To optimize our PRIS principle, we have developed a benchtop device with interchangeable light modules. The modular design is intended to provide maximum flexibility for determining appropriate PRIS stimulation parameters. In self-tests, we found that a pleasant entoptic perception occurs when a green luminous light spot (approx. 525 nm) moves on a circular path. The challenging part is to derive an objective diagnosis from a subjective phenomenon.

An unfulfilled pregnancy is often due to impaired patency of the female Fallopian tubes. To circumvent tubal obstruction, cost-intensive in vitro fertilisation (IVF) is currently indicated. The only therapeutic treatment concepts available are transvaginal tubal lavage/catheterization or laparoscopy with minimally invasive or complex surgical tubal reconstruction, which are associated with side effects. The development of new and cost-effective non- or minimally invasive therapeutic concepts that can restore the patency of the Fallopian tubes would be key in the treatment of female infertility and can fulfil the desire to have children. Therefore, in the present work, ex vivo anatomical studies are carried out on various laboratory mammals (pigs, rabbits, guinea pigs). Using these animal models, it was also evaluated whether a sensor-ureterorenoscope can be inserted through the whole female reproductive tract to the Fallopian tubes. This device will be used for endoscopically guided implantation of a novel tubal microstent prototype via its tailor-made delivery system into the isthmus region of the Fallopian tubes in upcoming studies. This work serves to identify an optimal species for a longitudinal animal study, in which the feasibility as well as the tissue reaction to the implant will be evaluated.

Female sterility is caused by Fallopian tube occlusions in one of three cases. Current treatment methods achieve unsatisfying pregnancy rates and are associated with high costs or significant psychological and physiological stress. Our previously described microstent technology opens up new therapeutic possibilities to restore the lumen of the Fallopian tube without surgery. In this work, a Finite Element Analysis model of a physiologically relevant loading of the device is presented. Therefore, microstent radial force was analysed as a function of the device diameter up to a minimum diameter of 1.4 mm, which was found after microstent implantation ex vivo. A bilinear constitutive material model considering isotropic hardening was used for modeling of the microstent. The Finite Element Analysis results were validated using corresponding results of experimental investigations. In this context, a maximum deviation of 15% between experimental radial force and the corresopnding simulation results (1.33 N vs. 1.13 N) was found. Maximum von Mises stresses of approximately 88 MPa were determined. A good agreement between simulation and experiments was found. Therefore, future simulations will be carried out as a basis for microstent design optimisation.

One of the greatest challenges in the development of novel implants is to find materials that optimally interact with the tissue and support the function of the implant over a long period of time. Especially considering the fact that biomaterials are used in multiple applications in modern implants, a better understanding of the physiology of the tissue in contact with the material becomes more and more important. To better understand the cellular responses to biomaterials, it is furthermore necessary that the models used reflect the physiological conditions at the implant site. However, in most cases, immortalized cell lines instead of tissue-specific primary cells are used to study the biocompatibility of implant materials. When interpreting these results, it is important to consider that cell lines differ significantly from primary cells found in their native environment. In this study, we examined the morphological differences between a cell line and primary cells upon contact with various implant structures resembling implant prototypes. Using a mouse fibroblast cell line in comparison with primary porcine fibroblasts, we discuss the results with respect to the use of cell lines for biocompatibility testing of biomaterials. Our results suggest that to better estimate meaningful results regarding the compatibility of implant structures, key control experiments should always be performed with specific primary cells.

Wound healing after implant surgery represents a spontaneous repair process that, when disturbed, can lead to a pathological situation known as fibrosis, characterized by excessive proliferation, increased extracellular matrix deposition, and scarring of the tissue. Tissue-specific cell culture models simulating physiological or pathophysiological cell responses are valuable research tools in the field of fibrosis, among others. In such in vitro systems, endpoint measurements are typically used to assess cell viability and/or proliferation. However, this approach is usually time consuming, costly and often leads to the destruction of the sample. Additionally, these conventional in vitro systems provide only a single snapshot of the respective sample at the end of the experiment. Therefore, we aimed to evolve the fibrotic disease in vitro model established by Stahnke et al. To this end, we chose a time-resolved, non-invasive approach based on cell impedance measurements and bright-field microscopy that allows continuous monitoring of the cells. Such measurements can be directly conducted using the xCELLigence RTCA eSight system. This system was used to characterize the cellular responses of the fibrosarcoma cell line HT-1080 and primary fibroblasts isolated from the Tenon’s capsule of human donors to TGF-β1, a key cytokine involved in the pathogenesis of fibrosis. The data shows that compared to Tenon’s fibroblasts the response of HT-1080 cells to TGF- β1 is less pronounced and only detectable within a narrow time frame. Thus, HT-1080 do not appear to be a suitable cell culture model for the assessment of antifibrotic implant coatings.

The increasing trend of minimally invasive therapy methods for widespread diseases in the cardiovascular system, in the field of ophthalmology, ear, nose, and throat medicine, or gynecology, leads to an extensive demand for innovative microdevice manufacturing technologies. Femtosecond (fs)-laser technology offers a wide range of applications in the field of cutting, milling, and surface structuring on the micro- and nanometer scale. Ophthalmic devices for glaucoma therapy have dimensions in the submillimeter range. Irrespective of this, there are high demands on the safety and efficacy of these implants. Within the current study, fs-laser-based manufacturing technologies for functional elements of a novel microstent for glaucoma therapy were developed, considering potential industrial scalability. We successfully developed a mounting mechanism for quick and reproducible manufacturing of a micromechanical valve mechanism for safe regulation of intraocular pressure. Furthermore, we successfully developed a fs-laser-based process for manufacturing grooves as part of a fixation mechanism for a stable device positioning inside the eye. The results show that fs-laser manufacturing represents a promising technology for manufacturers of medical microdevices, such as ophthalmic microstents.

Implant devices for micro invasive glaucoma surgery (MIGS) are gaining increasing acceptance in clinical ophthalmic use. The implant requirements are defined in international standards, such as ANSI Z80.27-2014 and the 2015 Guidance for Industry and Food and Drug Administration Staff “Premarket Studies of Implantable Minimally Invasive Glaucoma Surgical (MIGS) Devices”. The exact fluid-mechanical characterization represents a crucial part of the development and approval of innovative implant devices for MIGS. The current work describes the development and preliminary validation of a versatile test facility for pivotal characterization of glaucoma drainage devices. The test setup enables a pressurization of test specimens by means of two water columns. For measurement of pressure and volume flow, a pressure transducer and a total of three liquid flow meters were implemented into the test setup. Validation was conducted by experimental pressureflow characterization of standardized tubes and a comparison to theoretical results according to Hagen Poiseuille's law for stationary laminar flow of a Newtonian fluid in a tube with a circular cross section. Ultrapure water at (35 ± 2) °C was used for the analyses. The developed test setup potentially enables pressure-flow characterization of test specimens in a wide flow range of 0 μl min-1 ≤ Q ≤ 5.000 μl min-1. The preliminary test facility validation showed a good agreement of measured and theoretical volume flow characteristics as a function of the pressure difference, in the currently investigated flow range of Q < 80 μl min-1. The developed test facility is suitable for pivotal in vitro characterization of glaucoma drainage devices. Future investigations will focus on the final validation of the whole flow range and on the use of the test facility for fluid-mechanical characterization of self-developed prototypes of glaucoma microstents as well as commercially available glaucoma drainage devices.

The development of strategies for fibrosis prevention is a perpetual cutting the edge challenge, especially in ophthalmologic fistulating surgery. Stenosis of liquid draining implants but also fibrotic activation of implant-associated tissues are major clinical examples for fibrosis induced implant failure. Implant coating or incorporation of antifibrotic agents offer a promising approach to minimise failure rates. Nintendanib is a drug that has been successfully used for the treatment of ideopathic pulmonary fibrosis since 2015. In this study, we evaluated the suitability of Nintedanib for ophthalmic therapeutic treatment. Therefore, the antifibrotic potential of the active substance was tested with a fibrotic cell culture model on primary fibroblasts of the Tenon (hTF) in vitro. The concentration of 10μM Nintedanib demonstrated a marginal effect on cell viability but coincidently diminished cell proliferation remarkably. Both, immunocytochemical and Western blot analyses revealed a significant inhibitory effect of Nintedanib on the TGF-β1 induced expression of the extracellular matrix (ECM) components fibronectin and collagen. Moreover it supressed the expression and formation of stress fibres of the fibrotic marker protein alpha smooth muscle actin (α-SMA).

Despite decades of research, fibrosis still remains a significant challenge for medicine in many different fields. Although there is a general model of fibrosis, the causes and characteristics of the various pathologies are as diverse as the variety of organs and tissues that can be affected by fibrosis. Moreover, fibrosis also impedes the long-term prospects of success in implantation surgery. One possibility to address this challenge is the development of biocompatible implants featuring drug delivery systems loaded with antifibrotic pharmaceuticals. Due to diverse regulatory mechanisms in organs, tissues and also cell types, these active substances must consequentially be designed for diverse specific applications. Compared to fibrosis in organs like lung or liver, these mechanisms were poorly addressed in ophthalmologic research, but it is known that transforming growth factor beta (TGF-β) plays a key role. This gene expression study revealed 30 genes being upregulated more than two fold in TGF-β1 treated human primary tenon fibroblasts (hTF). Furthermore, 15 genes were found to be downregulated more than two fold. Tumor necrosis factor (TNF), vascular endothelial growth factor A (VEGFA) and inhibin beta (INHBE) were particular strongly regulated in TGF-β1 treated hTFs.

Glaucoma represents a chronic eye disease that becomes increasingly prevalent worldwide. Therapies are commonly based on the reduction of intraocular pressure (IOP). Implant devices for micro-invasive glaucoma surgery (MIGS) represent a promising therapy option in refractory cases but suffer from limitations in long term efficacy or from dislocation associated complications. Our approach of an innovative drug-eluting glaucoma microstent for MIGS was presented previously. Within the current work we developed concepts and prototypes of a mechanism for the fixation of our glaucoma microstent in the region of the corneal limbus. A tripod and a haptics design of the fixation mechanism were developed and manufactured. Semifinished products were tested with regard to dimensional stability and mechanical properties according to the standard ANSI Z80.27-2014. Considering the mechanical properties of ocular target tissues, a gelatin based in vitro model for the measurement of microstent retention force was developed. Retention force testing of microstent prototypes in vitro resulted in a proof of concept for the fixation mechanism. Future studies will focus on the use of smaller fixation fibers, for example commercially available suture material, and on an overall miniaturization of the fixation mechanism enabling the use of our applicator device with a 22G x 1½” cannula.

Primary open angle glaucoma represents an eye disease that usually is associated with an increased intraocular pressure (IOP). Implants for micro-invasive glaucoma surgery (MIGS) are gaining importance as a promising option for IOP lowering. Currently available devices are implanted into the eye ab interno based on a clear corneal incision and drain aqueous humour into the schlemm’s canal, suprachoroidal or subconjunctival space. Fibrosis is known as a major limitation for long term success and often leads to the necessity of an additional medication or a surgical re-intervention. The current work focusses on the development of an antifibrotic drug-eluting coating for a minimally invasive implantable glaucoma microstent. Tubular microstent base bodies manufactured from a polycarbonate based silicone elastomer were spray-coated with a chloroform based mixture of the same polymer and the antifibrotic drug pirfenidone (PFD, P2116, Merck KGaA, Germany) in a polymer/drug ratio of 85/15% (w/w). Coating mass of 89 μg according to a drug loading of 1.96 μg mm-2 was aspired. Coating mass was measured using an ultramicrobalance (XP6U, Mettler-Toledo International, Inc., Switzerland). Glaucoma microstent prototypes with a drugeluting coating mass of (84 ± 19) μg (n = 12) were manufactured. Characterization by means of scanning electron microscopy (Quattro S, Thermo Fisher Scientific, FEI Deutschland GmbH, Germany) yielded a reproducible smooth surface of the coating. High performance liquid chromatography (KNAUER Wissenschaftliche Geräte GmbH, Germany) was used for analysis of drug release behaviour in 0.9% NaCl solution at 37°C. The in vitro PFDrelease is characterized by an initial burst phase of approximately 6 h followed by a more retarded release phase. The entire drug was released within 36 h (n = 3). Sterilization processing has a minor impact on drug release kinetics. Appropriate drug stability after sterilization could be proven. Future studies will focus on the antifibrotic properties of drug-eluting glaucoma microstents in animal studies.

For minimising tissue reactions of implants hydrophilic silicone elastomers feature a high potential to be utilised as material for micro-implants in ophthalmologic pathology. To estimate the biocompatibility we quantified cell viability of human primary fibroblasts from scleral (hSF) and choroideal (hCF) origin in direct contact test and evaluated cell adhesion and cell morphology with Phalloidin- TRITC stained hSF and EA.hy926. Mechanical properties were analysed by means of uniaxial tensile testing. Direct contact testing revealed a good biocompatibility from 65 to 70% relative cell viability for hCF and moderate viabilities (46 to 63%) for hSF. EA.hy926 and also hSF exhibited typical cell morphology on the silicones. Improvement of cell adhesion was observed with increasing amount of hydrophilic component. Mechanical testing shows a minor decrease in elongation at break from 236% to 155% with increasing amount of hydrophilic component. These findings indicate that the investigated silicones may ensure a reliable integration of implants into the ocular tissues.

Implants that feature a drug delivery system loaded with antifibrotic active drugs provide a promising approach to address postoperative complications caused by fibrosis. This study is intended to clarify whether Actinomycin D has an impact specifically on components of the extracellular matrix (ECM) and its formation in human primary fibroblasts of the Tenon capsule (hTF). Furthermore, the suitability of this agent in poly(N-vinylpyrrolidone)- poly(methylmethacrylate)(PVP-co-PMMA) as a drug delivery model is evaluated in drug incorporation and release studies. RT-qPCR revealed a significant downregulation of the fibrotic marker genes ACTA2, COL1A1 and FN1 in cells stimulated with TGF- β1 and additionally treated with Actinomycin D. However, these findings could only be confirmed on α- SMA protein level. collagen I and Fibronectin synthesis stayed unaffected. The diffusion based incorporation of Actinomycin D into the polymer model proved to be very effective. The release of the agent was retarded with a slightly prolonged kinetic. These findings make Actinomycin D a promising antifibrotic agent in ophthalmic implant surgery.

Glaucoma is the leading cause of irreversible blindness worldwide. An increased intraocular pressure (IOP) is known as major risk factor. Currently, drainage devices that are implanted by means of minimally invasive glaucoma surgery (MIGS) represent a promising approach for IOP low-ering. Commercially available devices for MIGS suffer from unregulated drainage involving ocular hypotony. Further-more, long term drainage capability of current devices is limited by fibrotic encapsulation processes. Therefore, our group focusses on the development of a valved drug-eluting microstent for MIGS. Within the current work, we developed two alternative injector devices for minimally invasive mi-crostent implantation. Both injector devices were based on a cannula in which the microstent is loaded and a mandrel inside the cannula. Injector device A is designed to push the microstent out of the cannula and injector device B is de-signed to withdraw the cannula above the microstent. Manu-facturing of injector devices was conducted using rapid prototyping. Simplified polymeric microstents were manu-factured from polycarbonate based silicone elastomer. Simulated use was performed in a silicone eye model. The presented injector devices were suitable for minimally in-vasive ab interno microstent implantation into suprachoroidal space. Ongoing miniaturization of the microstent system will allow the use of a 22 G cannula in future ex vivo experiments.

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. Previous in silico drug screening and in vitro testing has identified the known antibiotic, josamycin, as a possible alternative antifibrotic medication with potentially fewer side effects. However, a suitable ocular delivery mechanism for the hydrophobic drug to the surgical site does not yet exist. Therefore, the focus of this paper is the development of an implantable drug delivery system for sustained delivery of josamycin after glaucoma surgery based on crosslinked γ-cyclodextrin. γ-Cyclodextrin is a commonly used solubilizer which was shown to complex with josamycin, drastically increasing the drug's solubility in aqueous solutions. A simple γ-cyclodextrin crosslinking method produced biocompatible hydrogels well-suited for implantation. The crosslinked γ - cyclodextrin retained the ability to form complexes with josamycin, resulting in a 4-fold higher drug loading efficiency when compared to linear dextran hydrogels, and prolonged drug release over 4 days.

Background: Childhood blindness remains a neglected issue in eye care within low-income countries, with congenital and juvenile cataracts being the most common treatable causes. This study aims to investigate the factors influencing the management of congenital and juvenile bilateral cataracts, provide data on general outcomes and postoperative findings, and discuss treatment in a low-income country context., Methods: In this prospective study, data from clinical care were continuously entered into a database, and one follow-up examination of a cohort of 91 patients with congenital and juvenile bilateral cataracts in Kinshasa, Democratic Republic of the Congo, was conducted. Multiple factors that affect the first clinical presentation, the clinical management, and outcome were investigated., Results: Most patients (88.5%) who received medical treatment were identified by cataract finders. A patient's presentation time was independent of the parent's education, social status, income, and sex of the child. The median age at first presentation was 5.8 years (ranging from 0 days to 17.3 years). The best visual acuity outcomes were achieved by patients who underwent surgery during early childhood. According to WHO grades and on an eye level basis, 51.1% (93 out of 182 eyes) showed improvement, while 34.6% (63 eyes) had unchanged results post-surgery. Among the cases without improvement, 76.2% were blind prior to surgery. Postoperative findings were observed in 56% of the patients, with secondary cataracts being the most common, affecting 26.37% of the operated eyes., Conclusions: Optimal management of childhood cataracts involves early identification, efficient hospital infrastructure, high-quality medical care, and long-term follow up. In sub-Saharan Africa, this approach must be adapted to the context of available resources, which differs significantly from those in high- and middle-income countries.

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). The aim of this study was to evaluate the applicability of two animal models and human donor eyes regarding RGM placement., Methods: Eyes were obtained from rabbits, pigs, and human body donations. After orbital exenterations, RGMs were placed in the anterior chamber draining in the subconjunctival space. X-ray contrast was increased by incubation in aqueous iodine solution for subsequent detailed micro-computed tomography (micro-CT)-based visualization and analysis., Results: In contrast to the human and porcine eyes, the stent extended far to the posterior pole with a more pronounced curvature along the globe in the rabbit eyes due to their smaller size. However, dysfunctional deformations were not depicted. Adequate positioning of the stent's inflow area in the anterior chamber and the outflow area in the Tenon space was achieved in both the animal models and the human eye., Conclusions: Micro-CT has proven to be a valuable tool for postoperative ex vivo evaluation of glaucoma drainage devices in its entire complexity. With regard to morphology, the porcine eye is the ideal animal model to test implantation procedures of the RGM. Nevertheless, rabbit eye morphology facilitates successful implantation results and provides all prerequisites for preclinical animal studies., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-23-905/coif). The authors have no conflicts of interest to declare., (2024 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

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. Critical point drying (CPD), as primarily used in scanning electron microscopy, offers an additional tool for improving differential contrast properties in soft tissue. In the visualisation of intraosseous soft tissue, such as the efferent lacrimal ducts, sample treatment by decalcification with ethylenediaminetetraacetic acid and subsequent CPD provides good results for micro-CT. Micro-CT can be used for a wide range of questions in 1. basic research, 2. application-related studies in ophthalmology (e.g. evaluation of the preclinical application of microstents for glaucoma treatment or analysis of the positioning of intraocular lenses) but also 3. as a supplement to ophthalmological histopathology., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht./The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

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. A total of 21 chicken eggs were fenestrated on Day 5 and allocated to either the control (n = 8) or exposition group (n = 13). The exposition group was treated with pulsed-wave Doppler ultrasound (PWD) for 10 min while controls remained without treatment. After subsequent incubation (6-48 h), the eggs were sacrificed, and chicken embryos were examined morphologically (HE-staining) and immunohistochemically. Counting of apoptotic and proliferating cells per retina was performed using antibodies specific for phospho-histone-H3 and active caspase-3 in combination with a biotin-labelled secondary antibody and peroxidase conjugated avidin-biotin complex for chromogenic detection. Due to a rather low number of specimens at each time point after ultrasound exposition, we neglected the effects of incubation time and focused on treatment effects. This approach revealed that the median number of proliferating cells is reduced after 10 min of exposure to PWD (569 vs. 766), while the number of apoptotic cells is fairly comparable between groups (5 vs. 6). Our data contribute to a better understanding of prenatal US on foetal development by suggesting that PWD could have an impact on the number of proliferating cells in the developing chicken retina and therefore justify further investigations., (© 2023 The Authors. Anatomia, Histologia, Embryologia published by Wiley-VCH GmbH.)

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. To reduce motion artefacts, the eggs were moderately cooled before and during MRI. Development of the upper extremity was anatomically and quantitatively assessed. Chondrification and ossification on MRI were correlated with histological examination. MRM allowed the identification of the embryo from stage D5 onwards. First chondrification of the upper extremity was visible at stage D7, and the differentiation of the forearm was possible from stage D9 throughout the developmental period with excellent correlation to histology. MRM also allowed the differentiation between cortical and medullary bone as well as the detection of chondrified areas. UHF MRM allows the in vivo and in ovo evaluation of the upper limb during embryonic development and provides non-invasive longitudinal anatomical information. This technique allows longitudinal studies of the same embryo during the developmental period and may therefore provide further insights into the development of the upper extremity. With improved coil technique and increasing availability of UHF MR systems, there is great potential regarding several research topics in experimental musculoskeletal radiology., (© 2022 The Authors. Anatomia, Histologia, Embryologia published by Wiley-VCH GmbH.)

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. Implants were manufactured using dip coating, fs-laser cutting, and spray coating. Within the current study no antifibrotic drug was loaded into the device. Sterilized microstents were analyzed in vitro regarding pressure-flow characteristics and biocompatibility. Six New Zealand white rabbits were implanted with a microstent draining the aqueous humor from the anterior chamber into the subconjunctival space. Drainage efficacy was evaluated using oculopressure tonometry as a transient glaucoma model. Noninvasive imaging was performed., Results: Microstents were manufactured successfully and characterized in vitro. Implantation in vivo was successful for four animals with additional device fixation. Without additional fixation, dislocation of microstents was found in two animals. Safe and effective intraocular pressure reduction was observed for the four eyes with correctly implanted microstent during the 6-month trial period., Conclusions: The described microstent represents an innovative treatment approach for MIGS. The incorporation of a selectively antifibrotic drug into the microstent drug-elutable coating will be addressed in future investigations., Translational Relevance: The current preclinical study successfully provided proof of concept for our microstent for MIGS which is suitable for safe and effective intraocular pressure reduction and offers promising perspectives for the clinical management of glaucoma.

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). Ocular quantitative systems pharmacology models provide the opportunity to describe the distribution of drugs in the eye as well as the resulting drug-response in specific segments of the eye. In particular, ocular physiologically-based PK (PBPK) models are necessary to describe drug concentration levels in different regions of the eye. Further, ocular effect models using molecular data from specific cellular systems are needed to develop dose-response correlations. We here describe the current status of PK/PBPK as well as PD models for the eyes and discuss cellular systems, data repositories, as well as animal models in ophthalmology. The application of the various concepts is highlighted for the development of new treatments for postoperative fibrosis after glaucoma surgery., (© 2023 The Authors. CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)

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 in vitro . Primary ocular fibroblasts were isolated, cultivated and a dose-response test including determination of the half maximal effective concentration (EC50) for KM was conducted. Transformation of fibroblasts into myofibroblasts was induced by TGF-β1and immunofluorescence (IF), and Western blot (WB) analyses were performed with fibroblasts and myofibroblasts. IF analyses were carried out using antibodies against α-smooth muscle actin (α-SMA) and fibronectin, and protein detection of intracellular and extracellular proteins was performed by WB. Using the dose-response test, the viability, cytotoxicity and EC50 of KM after 24 and 48 h were determined. Fibroblasts exposed to various KM concentrations showed no increase in α-SMA and extracellular matrix expression. In TGF-ß1-stimulated myofibroblasts, KM inhibited the expression of α-SMA and fibronectin in a concentration-dependent manner. These findings demonstrate that KM could impair the transformation of fibroblasts into myofibroblasts and the expression of proteins involved in fibrotic processes, representing a potential agent for specific fibrosis prevention in future therapeutic concepts., Competing Interests: The authors declare no conflict of interest.

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., Methods: Enucleated porcine eyes were prepared with ethanolic iodine (EI), aqueous iodine-potassium iodide, or ethanolic phosphotungstic acid (EPTA). Micro-CT scans of the samples were conducted in a moist environment with an isotropic resolution of 9.2-12.5 µm voxel size. Subsequently, samples were chemically dehydrated and critical point (CP) dried to conduct a second scan in a dry environment with a resolution up to 4.7-5.4 µm in voxel size. The visualization effects were qualitatively and semi-quantitatively evaluated with regard to the generated contrast between different ocular tissues., Results: All three contrast agents accumulated well in most of the investigated ocular tissues and lead to an increased X-ray attenuation which allowed for differentiated visualization of ocular structures. Problematic agent penetration into the lens was obvious for iodine-potassium iodide and EPTA. Artificial damages of the lens and thickness reduction for the cornea and sclera due to CPD were noticed. The effects of the different contrasting treatments are described and compared with regard to the effects of CPD. Exclusively CP dried samples that were not treated with contrast agents could also be visualized excellently with a good distinction of different ocular structures from each other., Conclusions: All ocular structures can be visualized by micro-CT. To contrast moist samples, the best results were achieved with iodine potassium iodide (IPI). CPD improved the scan quality in all cases. Even without pretreatment with contrasting agents, the CP dried samples showed a contrast similar to the IPI treated samples., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-22-109/coif). The authors have no conflicts of interest to declare., (2022 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

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. Group 1 included 262 patients with dense cataract. Group 2 consisted of 61 patients with pathologies of the ocular adnexa, and all were examined with a B-scan ultrasound. In group 1, there were 437 systematically screened eyes. Three hundred and ninety-eight eyes (91.08%) showed no abnormalities, 13 (2.97%) retinal detachments were identified, and 15 (3.43%) demonstrated a detached posterior hyaloid membrane. In the second group, 61 patients were examined (group 2). In 20 of them, surgery was performed for biopsy, tumor excision, mucoceles drainage, and palliative treatment. The need for routine B-scan examinations in dense cataract patients seems to be limited and can most likely be replaced by a thorough application of locally available examination techniques. B-scan application is recommended to manage orbital patients in the most cost-effective way.

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. The investigator asked the patients about their perception of the vascular pattern most commonly described as a leafless or dead tree. Visual acuity≥6/60 was considered an indication of good visual function and visual acuity<6/60 of poor function. Following small incision cataract surgery, best corrected visual acuity (BCVA) was determined and compared with the preoperative findings., Results: Out of 98 eyes, there were 80 (81.6%) where the Purkinje entoptic phenomenon was reported by the patients. After cataract surgery, out of the 80 eyes, there were 75 (93.8%) with a BCVA of better than 6/60, whereas in 5 eyes (6.2%), BCVA was 6/60 or less. Out of the 18 eyes (18.4%) where no Purkinje tree was recognized, there were 14 (77.8%) with BCVA of better than 6/60, whereas in 4 (22.2%) BCVA was 6/60 or less., Conclusion: The Purkinje entoptic test is successfully used for preoperative assessment of retinal function in patients with dense cataract. However, further investigation and refinement of the test is necessary to validate the method for use in sub-Saharan conditions., (International Journal of Ophthalmology Press.)

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 ex vivo ., Methods: After enucleation lens extractions were performed. Lenses were photographed, weighed, and embedded in 0.5% agarose dissolved in culture medium. UHF-MRI was conducted to analyze anatomical characteristics of the lens using T2-weighted Turbo-RARE imaging and to obtain apparent diffusion coefficients (ADC) measurements. A Gaussian fit routine was used to examine the ADC histograms., Results: An age-dependent increase in lens wet weight, lens thickness, and lens diameter was found (P<0.001). T2-weighted images revealed a hyperintense lens cortex and a gradually negative gradient in signal intensity towards the nucleus. ADC histograms of the lens showed bimodal distributions (lower ADC values mainly located in the nucleus and higher ADC values mainly located in the cortex), which did not change significantly with age [βPeak1=1.96E-7 (-20E-7, 10E-7), P=0.804 or βPeak2=15.4E-7 (-10E-7, 40E-7), P=0.276; respectively]., Conclusions: Clinically relevant age dependent lens hardening is probably not correlated with ADC changes within the nucleus, which could be confirmed by further measurements., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/qims-20-1124). Dr. TN reports other from MRI.TOOLS GmbH, Berlin, Germany, outside the submitted work. The other authors have no conflicts of interest to declare., (2021 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

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., Methods: A population-based cross-sectional study was conducted from July to August 2017. Children aged less than 16 years old were screened by volunteers in households and those with ocular pathologies were examined by two ophthalmologists. Prevalence and pattern of ocular diseases were determined., Results: A total of 4307 households were visited by the surveyors and 13,197 children were screened. Ocular pathologies were diagnosed among 399 children. Girls represented 50.7% of the children and the mean age ± SD was 9.2 ± 4.1 years. The overall prevalence of ocular morbidity in our population was 3.6% [95% CI 3.3-3.9]. Allergic conjunctivitis was the most frequent pathology (56.2%) followed by refractive errors (27.4%) and strabismus (5%). Age of children was the only risk factor with a significant impact on the frequency of ocular pathology. Forty-five percent of children had never benefited from any treatment, self-medication, and recourse to traditional treatments concerned respectively 18.%, and 2.3% of children., Conclusion: Childhood ocular morbidity in Kinshasa city was dominated by allergic conjunctivitis and refractive errors. The frequency of these conditions varies depending on the age of the children. Very few parents consult medical staff when their children have ocular problems, ignorance and limited financial resources are the principal barriers to consult., Competing Interests: The authors declare that they have no competing interests., (© 2021 The Author(s).)

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., Methods: 3D in vivo CLSM was performed on the eyes of volunteers (n=25) with a Heidelberg Retina Tomograph II equipped with an in-house modified version of the Rostock Cornea Module implementing two dedicated piezo actuators and a concave contact cap. Image data were acquired with nearly isotropic voxel resolution. After image registration, stacks of en-face sections were used to generate full-thickness volume data sets of the epithelium. Beyond that, an image analysis algorithm quantified en-face sections of epithelial cells regarding the depth-dependent mean of cell density, area, diameter, aggregation (Clark and Evans index of aggregation), neighbor count and polygonality., Results: Imaging and cell segmentation were successfully performed in all subjects. Thereby intermediated cells were efficiently recognized by the segmentation algorithm while efficiency for superficial and basal cells was reduced. Morphological parameters showed an increased mean cell density, decreased mean cell area and mean diameter from anterior to posterior (5,197.02 to 8,190.39 cells/mm 2 ; 160.51 to 90.29 µm 2 ; 15.9 to 12.3 µm respectively). Aggregation gradually increased from anterior to posterior ranging from 1.45 to 1.53. Average neighbor count increased from 5.50 to a maximum of 5.66 followed by a gradual decrease to 5.45 within the normalized depth from anterior to posterior. Polygonality gradually decreased ranging from 4.93 to 4.64 sides of cells. The neighbor count and polygonality parameters exhibited profound depth-dependent changes., Conclusions: This in vivo study demonstrates the successful implementation of a CLSM-based imaging pipeline for cellular characterization of the human corneal epithelium. The dedicated hardware in combination with an adapted image registration method to correct the remaining motion-induced image distortions followed by a dedicated algorithm to calculate characteristic quantities of different epithelial cell layers enabled the generation of normative data. Further significant effort is necessary to improve the algorithm for superficial and basal cell segmentation., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/qims-20-1052). Dr. KAS reports grants from German Federal Ministry of Education and Research, during the conduct of the study; Dr. KS reports grants from Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), during the conduct of the study; Dr. TS reports grants from German Federal Ministry of Education and Research, during the conduct of the study; Dr. SA reports grants from Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), during the conduct of the study; Dr. BK reports grants from Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), during the conduct of the study; SB reports grants from Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), during the conduct of the study. The other authors have no conflicts of interest to declare., (2021 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

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. Comparable structures were not observed in control corneas from healthy volunteers. Two hypotheses regarding the origin of these atypical structures are proposed. First, these structures might be keratocyte-derived myofibroblasts that entered the epithelium from the underlying stroma through breaks in Bowman's layer. Second, these structures could be proliferating Schwann cells that entered the epithelium in association with subbasal nerves. The nature and pathophysiological significance of these atypical cellular structures, and whether they are a direct consequence of the patient's diabetic neuropathy/or a non-specific secondary effect of associated inflammatory processes, are unknown.

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., Methods: A standardized surgical treatment of paediatric cataract was practiced on 298 children. Patient's follow-up, complications, and visual outcomes were recorded and analysed., Results: The mean age was 5.7 ± 4.3 years and males were predominant (64.9%). Most of children were living mainly in urban poorest areas (96.3%). Strabismus, nystagmus and microcornea were encountered in 20.1%, 25.1% and 8.7% of children, respectively. Using WHO criteria most of patients were classified as blind preoperatively and 81.9% of them had improved visual outcomes after surgery. Main reasons for reduced vision during follow-up were secondary cataract (5.7%), IOL decentration (1.2%), retinal detachment (1.2%), and secondary glaucoma (1.5%)., Conclusion: In spite of the post conflict challenges, elimination of cataract blindness in children remains a priority. Children present at a late age for surgery and long term follow-up is poor. There is need for program strengthening in these areas., (© 2020 Ngoy JK et al.)

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. The present study evaluates possible clinical uses of this method., Material and Methods: The essential innovations in CLSM are (1) a newly designed coupling element with superficial adaptation to corneal curvature and (2) the use of a dual computerised piezo drive for rapid and precise focusing. In post-processing and after elastic imaging registration of the individual images parallel to the surface, it is also possible to produce sagittal sections resembling a split lamp and with resolution in the micrometer range. The concept was tested on enucleated pig bulbi and tested on normal volunteers and selected patients with diseases of the cornea., Results: Simultaneous imaging in planes parallel to the surface and in sagittal planes provided additional information that can help us to understand the processes of wound healing in all substructures of the cornea and the role of immune competent cells. Possible clinical uses were demonstrated in a volunteer with healthy eyes and several groups of patients (keratoconus after CXL, recurrent keratitis, status after PRK). These show that this new approach can be used in morphological studies at cellular level in any desired and appropriate test plane., Conclusions: It could be shown that this new concept of CLSM can be used clinically. It can provide valuable and novel information to both preclinical researchers and to ophthalmologists interested in corneal disease, e.g. density of Langerhans cells and epithelial stratification in ocular surface diseases., Competing Interests: The authors declare that they have no conflict of interest./Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

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 0.9-mm spatial resolution. Patient dossiers were reviewed to record indication for magnetic resonance imaging examination and hypertension., Results: Advancing age was significantly correlated with increasing equatorial diameter of the infantile lens (r = 0. 74; 95% confidence interval, 0.58-0.85; P < .0001) and increasing crystalline lens signal intensity of the adult lens (r = 0.38; 95% confidence interval, 0.02-0.65; P = .0382), which remained significant after accounting for potential confounding variables. There was no significant correlation between age and axial thickness or vitreous body signal intensity in the children and adult cohort., Conclusions: The present study demonstrated that advancing age was significantly correlated with an increasing equatorial diameter of the infantile lens and with increasing crystalline lens signal intensity of the adult lens. These normative data can contribute to our understanding of age-related changes in eye health and function, especially in regard to the emmetropization process and should also be taken into account when investigating lens pathologies.

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. CLSM findings were compared with the severity of peripheral neuropathic (PNP) symptoms., Methods: The study enrolled 25 MM patients in which bilateral ophthalmologic examination was performed including unilateral CLSM. Further peripheral nerve function was clinically evaluated using the conventional neuropathy symptom and neuropathy deficit scores (NDSs)., Results: In 18/25 MM patients, CLSM detected atypical morphological appearance of bulb-like enlarged nerve endings in the corneal sub-basal nerve plexus. These neuromas were only found in patients showing moderate to severe PNP, in patients with mild or lacking PNP neuromas were absent., Conclusions: CLSM provides a novel non-invasive diagnostic tool for identification of neuromas in cancer patients affected by therapy or disease-related neuropathologies, perspectival allowing early neuronal degenerative process detection and monitoring., (© 2020 The Author(s).)

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. Joseph's Eye Hospital in Kinshasa (DR Congo). Small incision cataract surgery technique (SICS) was applied with the implantation of 6 mm PMMA lenses in the capsular bag. IOL refractive power choice was made to achieve a post-operative refraction of -0.5 dpt for the eye selected for far vision. The second eye received an implant heading for a post-operative myopia of -1.5 dpt suitable for intermediated and near vision. According to the literature, monovision criteria have been regarded as fulfilled when (a) far vision was 0.5 (logMAR) or better and (b) near vision was P3 (0.40, Decimal 32 cm) or better. Spectacle dependence after bilateral cataract surgery heading for monovision was analysed using a dedicated questionnaire., Results: Out of all 50 patients 22 (44%) fulfilled the above defined criteria of monovision in terms of post-operative refraction and visual acuity. About 19 out of these 22 (86.3%) patients were happy without glasses. Two of them used bifocal spectacles, whereas the remaining patient refused spectacles. About 28 patients did not fulfill monovision criteria. Out of these 28 patients, however, 9 (32.1%) of them are happy without glasses., Conclusion: In view of the described local circumstances aiming for monovision after bilateral cataract surgery is a suitable approach to optimise cataract surgical outcomes with no extra costs for surgery but considerable improvement of patient's visual performance in daily life., (© 2020 The Authors. International Journal of Clinical Practice published by John Wiley & Sons Ltd.)