bluuebunny/crossref_metadata_2025_split huggingface dataset:
Alternatives for corneal stroma replacement
Authors: Ahearne Mark 
Published: December 2022

AbstractCorneal blindness affects millions worldwide. The global shortage of donor corneas suitable for transplantation has led to the development of biomaterial‐based alternatives. The unique composition and structure of the corneal stroma are a significant challenge to replicate using conventional biomaterials and material fabrication techniques. One approach to overcome this problem is to decellularize the corneal stroma taken for animals, as these have similar structural properties and composition to native human stroma. This talk will provide an overview of the work done by our group in developing different decellularization approaches that can be used to fabricate corneal stromal constructs. A number of different decellularization techniques have been examined and their effectiveness at removing cells and cellular components while still maintaining the stromal extracellular matrix has been evaluated. New methods to recellularize the decellularized corneal stromal constructs have been explored. The development of decellularized corneal hydrogels and their advantages and limitations, shall all be discussed.
Artificial cornea: Myth or reality?
Authors: Lagali Neil 
Published: December 2022

AbstractSince the first human corneal transplantation was performed by Eduard Zirm over 110 years ago, the paradigm of using human donor corneas for treating blinding corneal disease has remained largely unchanged. Intense research efforts, however, have been undertaken during the past decades, to engineer an alternative to the human cornea to meet the large global demand for this specialized donor tissue. The various artificial, or engineered corneas that have reached preclinical and in several cases clinical testing during the past years will be presented, along with the advantages and limitations of each technology. Various technologies use either cell‐free or cell‐loaded tissues, de‐cellularized or re‐cellularized human or animal tissues, and aim to replace various layers of the cornea or in certain cases, the entire cornea. For the most prevalent indications for corneal transplantation, however, human donor tissue remains the method of choice due to the unparalleled visual outcomes. Nevertheless, newer emerging treatment methods and alternatives to donor cornea transplantation are being reported, that can potentially ease the global demand for donor tissue and tissue banking in the future. Here we present these developments and provide the latest update on the most promising engineered corneal replacements tested in the clinic.
Bacterial keratitis – Challenges with changing microbial resistance
Authors: Modis László 
Published: December 2022

AbstractAbout 90% of corneal infections are bacterial in origin. The most common pathogens are Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae and Pseudomonas aeruginosa. The two main causes of bacterial keratitis are contact lens usage and corneal injury.Patients typically complain of pain, sensitivity to light, blurred vision, tearing and yellowish purulent discharge. Clinical signs of bacterial keratitis include epithelial defect, ulceration in addition, stromal oedema and infiltrates with indistinct margins are present. Purulent material may appear in the anterior chamber.Most cases can be successfully treated with empiric therapy. If the pathogen is not known, moxifloxacin or cefazolin with tobramycin or gentamycin recommended as primary treatment. For severe keratitis eye drops should be applied both day and night for the first 48 hours. If the causative agent and its susceptibility are available from the microbiological sample and/or from smear, the topical treatment should be adjusted accordingly. If no improvement in the clinical picture seen after 48 hours with topical treatment, repeat sampling for microbiological culture recommended. In case of further progression, keratectomy with histological evaluation of the specimen is necessary. Corticosteroids may be considered after 48 hours when the infective organism is identified, and the keratitis is responding to therapy.In addition to antimicrobial treatment pupillary dilation advised to immobilize the iris and ciliary body. Cycloplegia may also decrease pain as well as synechia formation. In therapy resistant cases crosslinking may be an additional option if herpetic origin can be excluded.If the clinical picture does not improve, it is important to reassess the differential diagnosis of the keratitis caused by herpetic, fungal and Acanthamoeba infection.In cases of non‐healing and rapidly progressive corneal inflammation or ulceration, therapeutic corneal transplantation is recommended. However, surgery has a better prognosis in the non‐inflammatory period when the eye is quiet.
The chameleon of herpetic keratitis
Authors: Seitz Berthold 
Published: December 2022

AbstractIn Europe, herpes simplex virus type I (HSV) is a common cause of keratitis. The disease may be well treated if the ophthalmologist is aware of the various types of clinical expressions of this typical unilateral chameleon, and treatment is adjusted accordingly. Types of expression include 1. epithelial keratitis (dendritica/ geographica), 2. stromal keratitis (necrotizing “ulcer” “vs. non‐necrotizing = interstitial keratitis”), 3. endotheliitis (= “disciform keratitis”), 4. so‐called “metaherpetic keratitis” (= neurotrophic keratopathy), 5. (vascularized) corneal scars. In the acute phase, concomitant ocular hypertension should be treated predominantly without surgery (no prostaglandin analoga!). After keratoplasty and in case of severe recurrences of herpetic keratitis, systemic acyclovir application (2 × 400 mg/day) for at least 1 year is indispensable! In 1.5% of corneal excisions during keratoplasty, HSV PCR is positive without clinical suspicion of herpetic keratitis. This may be one reason for primary or secondary graft failure and needs adequate treatment.
Imaging and check‐up for evolutive myopia
Authors: Bremond‐Gignac Dominique 
Published: December 2022

AbstractMyopia is the most common ocular pathology with a major recent increasing in Asia and all over the world. This refractive anomaly has usually an onset during infancy. However, myopia is not only a refractive pathology but it may also lead to retinal complications. When myopia is diagnosed, a complete check‐up should be performed including VA, refraction under cycloplegia, orthoptic check‐up, optical axial length, fundus and if possible ultra‐wide field fundus and macular OCT. These examinations lead to propose the best‐adapted system for myopia control. The follow‐up of myopia include systematically VA, Refraction under cycloplegia and optical axial length. Practical cases will be described for a better understanding of myopia evolution in children.
Pathophysiology of intraocular haemorrhage: Role of iron in cell death
Authors: Picard Emilie , Youale Jenny , Daruich‐Matet Alejandra , Behar‐Cohen Francine 
Published: December 2022

AbstractRetinal haemorrhages are present in several retinal pathologies, such as exudative AMD, diabetic retinopathy, or myopic degeneration. As a consequence of erythrocytes lysis following haemorrhage, haemoglobin (Hb) is released into the extracellular space, and heme is degraded into iron, which becomes under a free (unbound) form. While iron is essential for retinal functions, labile free iron enhances Fenton reaction and therefore leads to oxidative stress. Cones are the most sensitive retinal cells to iron excess and local accumulation of iron rapidly induces photoreceptors and retinal pigment epithelium cells death. A local retinal homeostasis of iron exists to equilibrate iron level in retinal cells, but a deficiency of iron‐related proteins causes iron accumulation and retinal degeneration. Heme‐binding proteins, hemopexin and haptoglobin, and their receptors, as well as heme transporters were also found expressed in retinal cells suggesting their roles in retinal iron regulation. As therapeutic strategy, chemical chelators used to control iron accumulation in systemic iron overload diseases, have demonstrated efficiency to protects the retina in various models of retinal degenerations. Our team uses transferrin (TF), the iron transporter protein, to reduce iron overload and therefore preserve visual function. Control of iron impairment in retinal tissues may be a therapeutic strategy during haemorrhages.
Maturation of stem cell derived retinal organoid cells following subretinal transplantation
Authors: Singh Mandeep S. 
Published: December 2022

AbstractRetinal cell therapy is envisioned as a treatment modality to repair the retina and improve vision in people with degenerative or hereditary retinopathies. In pursuit of this goal, transplantation of ES/iPS‐derived photoreceptor precursor cells is being developed as a treatment to replace lost photoreceptor cells. Several studies have shown that photoreceptor precursors can mature and incorporate into the recipient retina following transplantation in the subretinal space. However, knowledge regarding the identity and distribution of transplanted cells is incomplete, and furthermore, how closely the transplanted photoreceptors resemble normal photoreceptors in an intact wild‐type retina is unclear. In addition, a key gap in knowledge pertains to how the recipient retina regulates the maturation, fate specification, and migration of transplanted donor cells. This talk will describe how the subretinal space in the degenerative recipient eye promotes the maturation of transplanted rod and cone photoreceptor cells. In addition, observations of graft‐derived cells that migrate into the recipient retina, including some that travel long distances away from the graft, are presented. These findings highlight that in vitro human micro‐organogenesis can produce complex organoids with unusual and unexpected ectopic components that do not typically comprise the normal organ, and thus can profoundly influence therapeutic studies that use those organoids. These findings demonstrate the importance of the extracellular microenvironment in determining cell identity and behaviour in human organoids being developed for treatment purposes.
Retinal structure: From Cajal drawings to present morphological techniques
Authors: Cuenca Nicolás 
Published: December 2022

AbstractThe scientist Santiago Ramón y Cajal and his work on the organization of the nervous system and the Neuronal Theory are widely known. However, his studies and contributions on the structure of the retina remain almost forgotten. La rétine des vertébrés, appearing in the journal La Cellule (1892), is a masterpiece of scientific literature, frequently cited in scientific articles even today. In this presentation we want to highlight his work on the neuroanatomy of the retina as well as his excellent descriptions and artistic drawings of its cells. Santiago Ramón y Cajal published his first studies of the retina using the Golgi technique in 1888. Cajal describes in detail the histology and anatomy of the retina of the various types of vertebrates. His studies of the structural organization of the retina, as well as the almost prophetic predictions he made about its functions, have become the basis of retinal neuroanatomy, neurophysiology, and neuropathology. The descriptions made by the scientist on the types of retinal cells in different species and on the way in which these cells are interconnected are the most outstanding and complete that have been carried out. The new techniques of confocal microscopy and immunocytochemistry allow us to morphologically identify the various cell types as well as the synaptic connections between them and ratify the ideas proposals by Cajal.
Biomechanical effect of intracorneal ring segment implantation
Authors: Hamon Loïc , Pfahl Luisa J. , Flockerzi Elias , Berger Tim , Langenbucher Achim , Seitz Berthold , Daas Loay 
Published: December 2022

AbstractBackground: Previous studies have reported significant differences in corneal biomechanics between keratoconic and healthy corneas. Corvis ST® (CST – OCULUS, Wetzlar, Germany) and Ocular Response Analyser® (ORA – Reichelt Inc., Depew, NY, USA) are two single central air‐puff tonometers and are commonly used to analyse the corneal biomechanics. Implantation of intracorneal ring segments (ICRS) using a femtosecond laser represents a reliable surgical option to widen the spectrum of the stage‐related therapy of keratoconus for selected patients. Our purpose was to analyse the change in corneal biomechanical properties after ICRS implantation in keratectasia.Methods: This retrospective monocentric study included 118 patient eyes that underwent femtosecond laser‐assisted ICRS implantation (INTACS SK®, Addition Technology Inc., Des Plaines, IL, USA) for keratectasia. Biomechanical analysis was performed using both ORA, with determination of Corneal resistance factor (CRF), Corneal hysteresis (CH) and Keratoconus Match Index (KMI), as well as by CST with determination of stiffness parameter A1 (SP‐A1), Ambrosio's related thickness to the horizontal profile (Arth), integrated radius (IR), deformation amplitude‐ratio (DA‐ratio) as well as Corvis Biomechanical Index (CBI) and Tomographical Biomechanical Index (TBI). Data collection was performed preoperatively and after 6 months postoperatively for ORA and CST and additionally after 1 and 2 years for ORA.Results: The CRF decreased significantly postoperatively (5.8 ± 1.7 mmHg) compared to preoperatively (6.8 ± 3.7 mmHg; p < 0.001), and increased again during follow‐up (6.2 ± 1.9 mmHg; p = 0.001), without regaining preoperative values. CH and KMI did not change significantly. SP‐A1, IR and DA‐ratio increased significantly after ICRS implantation (p < 0.001). Arth decreased significantly from 190 ± 88 to 157 ± 108. However, there was no significant postoperative change for CBI and TBI.Conclusions: Corneal biomechanical properties showed inconsistent changes after ICRS implantation. The classical corneal biomechanical parameters (using single central air‐puff tonometers) do not seem to be suitable for follow‐up after ICRS implantation.
Laser vision correction in glaucoma; myths and reality
Authors: Patsoura Elisabeth 
Published: December 2022

AbstractLaser vision correction has been a well‐established, rapidly developing, safe and widely used technique for refractive error correction. Nevertheless, there are several drawbacks for its use in specific groups of patients. A classic contraindication has been patients with glaucoma. These include those with diagnosed glaucoma and even glaucoma suspects. The main concern remains the evaluation of the intraocular pressure (IOP) after refractive surgery. Newer technology has been helpful in achieving accurate IOP measurements bypassing to an extend the biomechanical changes and thinning of the cornea induced by laser correction. Use of conversion factors may well be applied. Perioperative care of these patients has also been an issue as corticosteroids drops are used, sometimes for a prolonged period of time potentially causing a rise in IOP. Choosing between superficial techniques and LASIK, the former inducing high intraocular pressure during flap dissection is also a question to be answered. In addition, following up those patients to assess possible glaucoma progression can be challenging. Thorough preoperative assessment is mandatory with functional and anatomical testing of the optic nerve. This is especially important so new glaucoma disease is not missed especially in high myopes. Last but not least patients on glaucoma treatment usually have a compromised ocular surface due to the long‐term effects of topical drops. This fact has to be taken into consideration when deciding to proceed or not with laser refractive surgery. In conclusion the glaucoma patient and the glaucoma suspect are challenging patients regarding the potential laser vision correction. Several factors need to be considered in order to make the correct decision. So, myths andreality are analysed that either defeat or support the argument that under the laser vision correction can be safely performed in carefully selected glaucoma eyes.
Update on Boston KPro1
Authors: Hannush Sadeer 
Published: December 2022

AbstractSince the introduction of the last major iteration of the Boston Type I keratoprosthesis in 2002, it has undergone several improvements, including the development of a titanium back plate in two sizes, a click‐on version, and the recently introduced Lucia. The Lucia is currently available in one aphakic power with a blue or brown back plate that incorporates radial slit apertures to both allow aqueous nutrition of the carrier donor cornea and simulate the natural iris. Moreover, the Lucia can be produced at low cost, making it more accessible to those in need around the world.
Update on tibial bone keratoprosthesis
Authors: de la Paz Maria 
Published: December 2022

AbstractOsteo‐odontokeratoprosthesis (OOKP) is the gold standard for end stage cicatricial disease of the ocular surface to restore sight in patients with corneal blindness. The use of tibial bone is an option in cases of edentulia or when patient refuses to sacrifice a tooth. The surgery consists in retrieving a disc of the tibial bone and inserting an optical cylinder in the center, much like in OOKP surgery using a canine tooth.A review of 113 patients who underwent tibial bone keratoprosthesis (Tibia KPro) at a single center performed by a single surgeon showed prosthesis retention rate of 69% at 5 years and 54% at 10 years. BCVA better than or equal to decimal 0.05 at 5 years was 33% and 19% at 10 years. Patients with chemical burn had better prosthesis retention as well as visual acuity results compared to autoimmune cases. Complications found postoperatively were keratoprosthesis extrusion, glaucoma, retinal detachment, buccal mucosa necrosis, retroprosthetic membrane, etc.The anatomical results in the long‐term are comparable to OOKP (67% prosthesis retention at 10 years). However, the visual acuity results with OOKP at 10 years was better at 49% (for BCVA better than or equal to decimal 0.05) than patients with Tibia KPro. Moreover, there were more complications in Tibia KPro than in OOKP such as mucous membrane necrosis and retroprosthetic membrane formation.At present, in vitro studies are being undertaken to produce substitutes for OOKP skirts using biomimetic bone‐like composites.
What has COVID taught us about glaucoma management?
Authors: Normando Eduardo 
Published: December 2022

AbstractSince the spread of coronavirus pandemic caused by the SARS‐CoV‐2 virus, several measures were implemented worldwide to try to stop the pandemic and minimize its impact on healthcare.Ophthalmologists are one of the most exposed specialists to airborne particles due to their close proximity to patients' faces during the examination.Therefore during the pandemic, all non‐essential procedures and appointments were cancelled or postponed, and new approaches to virtual clinics were explored.This presentation will discuss the impact of Covid related delayed care in patients with glaucoma and how the implementation of virtual and diagnostic clinics had on reducing long waiting list and streamlining patient's care .
Future approaches to glaucoma management
Authors: Cordeiro Francesca 
Published: December 2022

AbstractThere have been several advances in glaucoma management over the past few years. This talk will include coverage of medical changes such as neuroprotective strategies and sustained release medications, and diagnostic advances including artificial intelligence applications, the water drinking test, DARC, visual field analysis and tear fluid assessment. Finally, home monitoring possibilities in glaucoma including self‐tonometry and visual field testing will be discussed.
Development of co‐encapsulating bevacizumab and dexamethasone liposomes with cell penetrating peptide surface functionalisation for posterior eye drug delivery
Authors: Farooq Umer , Fitzhenry Laurence , O'Reilly Niall , Behl Gautam , Ahmed Zubair , Gasco Paolo , Singh Thakur Raghu Raj , Mcloughlin Peter 
Published: December 2022

AbstractBackground: Intravitreal injections to the eye are the standard treatment for wet age‐related macular degeneration (AMD) but are associated with several drawbacks. Intravitreal injections not only cause structural damage but the invasive procedure also causes discomfort and pain, resulting in decreased patient adherence to the therapy. Our work aims to develop a topical liposomal formulation, functionalised with a cell penetrating peptide (CPP) that has the potential to reach the posterior segment of the eye and inhibit neovascularisation and inflammation, which are the hallmarks of wet AMD and Diabetic Retinopathy. The proposed formulation will offer non‐invasive administration (topical) with decreased dosing frequency (owing to its sustained release action), facilitating increased patient compliance.Methods: The liposomes were prepared by the thin film hydration method, followed by the extrusion of obtained multilamellar vesicles into single unilamellar vesicles. The formulations were characterized for their size, PDI and % encapsulation efficiency (%EE). Initially, a Design of Experiments approach was adopted to optimize the encapsulation efficiency of dexamethasone in liposomes, with the amounts of DPPC, cholesterol and dexamethasone being the factors and the size, PDI and %EE as the responses. HPLC was used to quantify the amount of encapsulated dexamethasone. Bevacizumab was then co‐loaded with optimized dexamethasone liposome formulation and bicinchoninic acid (BCA) assay was used to quantify the amount of encapsulated bevacizumab in the liposomes.Results: Liposomes with an average size of 137 ± 3 nm, PDI of 0.07 ± 0.03 and a zeta potential of −3.09 ± 0.42 were synthesized. Dexamethasone encapsulation efficiency was improved from initially observed value of 13.01 ± 0.06 to the optimized value of 52.8 ± 2.5. This optimized formulation has a %EE 5.8 time greater than the previously reported values for DPPC‐dexamethasone liposomes (1). Bevacizumab was successfully co‐encapsulated into the liposomes along with dexamethasone. Bevacizumab demonstrated %EE of 91.3 ± 4.07 in the dual encapsulated liposomes, whereas %EE of dexamethasone was 75.1 ± 4.4.Further studies: The liposome formulation will be functionalised with the CPP and characterized for drug release, transport through ocular layers, cytotoxicity, anti‐angiogenesis and anti‐inflammatory activities using in vitro, ex vivo and in vivo models.References1. Bhardwaj U, Burgess DJ. Physicochemical properties of extruded and non‐extruded liposomes containing the hydrophobic drug dexamethasone. Int J Pharm. 2010;388(1–2):181–9.This project is funded by the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska‐Curie Actions (grant agreement – No 813440).