Eyeworld

Reporting from the XXXV Congress of the ESCRS, October 7–11, Lisbon, Portugal EW MEETING REPORTER 88 endothelium over standard DMEK could allow for the production of autologous grafts, several grafts from a single donor, and improvement in the quality of human donor corneas. "The paradigm of treating corneal disease has and continues to change," Dr. Brunette said. "It's about giving the cornea what it needs to heal itself." This means promoting tissue regeneration, modulating inflammation, combat- ing infection and vascularization, and gene therapy. We now have the knowledge, expertise, and resources that we should soon be able to build new corneas, Dr. Brunette said. Retinal prosthesis technology has also moved forward. Veit Peter Gabel, MD, Munich, Germany, gave an overview of the previous and current research on stimulating ar- tificial vision for the blind, focusing on the current state of epiretinal and subretinal implants. Systems that target the epiret- ina include the FDA-approved, CE-marked Argus II system (Second Sight, Los Angeles), which consists of an external camera that sends information in the form of electrical pulses to a retinal encoder, which are sent to a stimulator of 60 elec- trodes on the surface of the retina. Dr. Gabel said studies of patients with this technology are able to per- form target localization and detect extracellular matrix in vitro, which allows for the production of thick sheets of cellularized stroma substi- tute. One advantage of this ap- proach is that a living graft, such as this, preserves interactions between cells and their environment. Keratocytes have been used to tissue engineer stroma. Sixteen of these grafts were generated and implanted in eight cats. After a follow-up of 4 months, the graft was clear and clinically highly function- al. However, Dr. Brunette said longer follow-up is needed before this is ready for clinical application, and the grafts were too soft to be sutured and were not strong enough for full thickness replacement. In the category of acellular biomaterials acting as regeneration scaffolds, recombinant human collagen stromal scaffolds have been developed, and research has shown repopulation by stromal cells and nerves with sensitivity that was recovered better and faster in implanted corneas than in penetrat- ing keratoplasty controls. Further clinical testing is needed for this, Dr. Brunette said. Tissue engineering for corneal endothelium has also taken place with implantation in the cat model showing normal endothelium mor- phology and ultrastructure, uniform distribution of function-related proteins, and clear transparency. Using tissue-engineered corneal endothelial decompensation. Retinal detachment is the main concern, however, and Dr. Badoza noted that after surgery, the reduction of the volume occupied by the lens may allow the vitreous to move. PVD fre- quently occurs after surgery, which predisposes the patient to retinal detachment, especially in eyes with lattice areas. Dr. Badoza added that phaco increases retinal detachment in the whole cataract population in short, normal, and long eyes, according to study data. Risk factors for retinal detachment are young patients, male patients, and long axial length. "Building a new eye" "Not so long ago, the idea of talking about building a new eye would be laughable," said Daniel Epstein, MD, Bern, Switzerland, co-chair of a symposium on the topic. "We can start laughing because unimaginable things are happening." Isabelle Brunette, MD, Montre- al, Canada, presented information on tissue-engineered corneas. With corneal blindness being the third leading cause of blindness world- wide and human donor corneas only being available in a 1/70 ratio for those who need it, Dr. Brunette said there is a need for alternatives. The production of a stromal substi- tute faces two challenges: (1) achiev- ing a balance between transparency and affinity for cells, and (2) cells vs. no cells within the implant. Dr. Brunette cited four catego- ries of stromal substitutes: (1) acel- lular inert materials impermeable to cells; (2) biomaterials enhanced with cells at the time of production; (3) stromal substitutes entirely engi- neered from cells; and (4) acellular biomaterials that function as pro-re- generation scaffolds. Biomaterials enhanced with corneal stromal cells at the time of production is best illustrated by a fibrin and agarose scaffold that has been developed with cells (allogene- ic corneal fibroblasts and a surface covered with limbal epithelial cells). This scaffold has shown adequate stiffness, resistance, and elasticity. A stromal substitute engineered entirely from cells allows the cells to maintain their ability to deposit November 2017 continued on page 90 View videos from ESCRS 2017: EWrePlay.org Eric Donnenfeld, MD, reports results on the use of NSAIDs after cataract surgery.

• Blank Page
• Blank Page (1)