Search results for "Corneal Transplant"
showing 10 items of 12 documents
Trasplante de córnea: aspectos bioéticos
2019
Resumen: Este trabajo aborda los aspectos bioéticos del trasplante de córnea, desde la donación y los tipos de la misma, incluyendo el comercio de órganos y tejidos, así como la metodología del trasplante y el uso de tratamientos inmunosupresores, además del consentimiento informado y la participación del paciente en las decisiones. Se analizan las técnicas actuales, la efectividad y las circunstancias en las que se puede aplicar cada una de ellas así como los estudios emergentes basados en la terapia celular. Algunos de los estudios emplean células troncales derivadas de embriones humanos, y otras de tejidos adultos y células troncales pluripotentes inducidas (iPS). Se propone un análisis …
Pēcoperācijas perioda izvērtējums pēc radzenes transplantācijas vispārējā anestēzijā
2020
Bakalaura darba tēma ir “Pēcoperācijas perioda izvērtējums pēc radzenes transplantācijas vispārējā anestēzijā”. Darba tēmas aktualitāte ir tajā, ka radzenes transplantācijas operācijas visā pasaulē un Latvijā tiek veiktas arvien vairāk, tāpēc ir būtiski novērtēt pēcoperācijas periodu pēc šīm operācijām, lai izvērtēt aprūpes procesu, pacientu sūdzības un dokumentācijas kvalitāti un nepieciešamības gadījumā veikt uzlabojums. Darba mērķis ir izvērtēt pēcoperācijas periodu pacientam pēc radzenes transplantācijas operācijas vispārējā anestēzijā. Bakalaura darba mērķa saniegšanai autore izvirzija sekojošus darba uzdevumus - apkopot un analizēt zinātnisko literatūru par radzenes transplantāciju un…
A new approach based on Machine Learning for predicting corneal curvature (K1) and astigmatism in patients with keratoconus after intracorneal ring i…
2014
Keratoconus (KC) is the most common type of corneal ectasia. A corneal transplantation was the treatment of choice until the last decade. However, intra-corneal ring implantation has become more and more common, and it is commonly used to treat KC thus avoiding a corneal transplantation. This work proposes a new approach based on Machine Learning to predict the vision gain of KC patients after ring implantation. That vision gain is assessed by means of the corneal curvature and the astigmatism. Different models were proposed; the best results were achieved by an artificial neural network based on the Multilayer Perceptron. The error provided by the best model was 0.97D of corneal curvature …
Corneoscleral contact lenses for visual rehabilitation after keratoplasty surgery.
2019
Abstract Purpose To report the use of corneoscleral lenses (CSL) in keratoconus patients who were unsatisfied with their visual outcomes after keratoplasty surgery. Methods Eleven consecutive cases with unsatisfactory vision with spectacles, due to irregular astigmatism, preferred to try CSL before SL due to handling or economic issues. An eye examination included refraction and visual acuity assessment, anterior eye biomicroscopy, ocular fundus examination, corneal topographic analysis, endothelial-cell count (ECC) and evaluation of corneal biomechanical parameters (corneal resistance factor, CRF; corneal hysteresis, CH; corneal-compensated intraocular pressure, IOPcc). The fitting process…
Measuring the Spatial Homogeneity in Corneal Endotheliums by Means of a Randomization Test
1999
Quantification of regularity of cell sizes and the spatial arrangement of cells in corneal endotheliums becomes of a great importance associated to stress situations such as cataract surgery, corneal transplantation or implantation of intra-ocular lenses. A new index of regularity of the spatial distribution of cell sizes in corneal endotheliums is proposed. The corneal endothelium is described by means of a spatial marked point pattern (the cell centroids marked with the cell areas). The hypothesis of no dependency between mark and locations is tested by a Monte Carlo test. The new index is the p-value of the test validating the hypothesis. Pairs of endotheliums from different eyes of the …
Amyloidosis and Ocular Involvement: an Overview.
2019
Purpose: To describe the ophthalmic manifestations of amyloidosis and the corresponding therapeutic measures.Methods: The 178 patients included in the study had different types of amyloidosis, diagnosed at a single internal medicine institution (Bari, Italy). To provide a comprehensive review of the types of amyloidosis that can be associated with ocular involvement, the images and clinical descriptions of patients with amyloidosis structurally related to gelsolin, keratoepithelin and lactoferrin were obtained in collaborations with the ophthalmology departments of hospitals in Mainz (Germany) and Helsinki (Finland).Results: Overall, ocular morbidity was detected in 41 of the 178 patients w…
Survival After Transplantation of Corneas From a Rabies-Infected Donor
2011
To examine the tissue samples of 2 corneal recipients from a rabies-infected donor for the presence of rabies to explain their survival.Interventional case series with a review of the literature. The explanted corneal donor buttons were examined via nested reverse transcriptase polymerase chain reaction. The patients were followed up ophthalmologically and neurologically. Antirabies antibodies were measured in blood samples, and skin biopsies were examined by direct fluorescent antibody staining.Two patients received corneas from the same multiorgan donor. Six weeks after transplantation, 3 of the donor's organ recipients became symptomatic and rabies virus was confirmed in tissue from the …
Proposal of a new diffractive corneal inlay to improve near vision in a presbyopic eye
2020
[EN] A new class of diffraction-based corneal inlays for treatment of presbyopia is described. The inlay is intended to achieve an improvement of the near focus quality over previous designs. Our proposal is a two-zone hybrid device with separated amplitude and phase areas having a central aperture and no refractive power. An array of micro-holes is distributed on the surface of the inlay conforming a binary photon sieve. In this way, the central hole of the disk contributes to the zero order of diffraction, and the light diffracted by the micro-holes in the peripheral photon sieve produces a real focus for near vision. We employed ray-tracing software to study the performance of the new in…
Evolution of Corneal Graft Survival Over a 30-Year Period and Comparison of Surgical Techniques: A Cohort Study.
2015
Purpose To compare graft survival between 3 10-year periods and according to surgical techniques performed in the last years. Design Cohort study. Methods setting: Regional center (Besancon University Hospital, France). patients: All 1132 patients operated on between 1983 and 2014. Graft and patient baseline characteristics, risk factors for failure, surgical procedures, and postoperative corneal status were collected. main outcome measures: Five-year survival rate in the whole cohort; 1-year and 3-year survival rates, respectively, among 88 patients with endothelial dystrophy (ED) or postoperative bullous keratopathy (PBK) operated on using endothelial lamellar keratoplasty (ELK) or penetr…
Tierexperimentelle untersuchungen zur rolle von entzündungsmediatoren bei der hornhautneovaskularisation
1984
Experimental investigations concerning the role of inflammatory compounds in corneal neovascularization.Natural and synthetic inflammatory compounds were implanted in the corneas of rabbits to clarify the question whether corneal neovascularization is induced by stromal edema alone, or by neovascular mediators. It could be demonstrated that prostaglandin E1 and E2 have an angiogenetic capacity, whereas their precursor (arachidonic acid) as well as PGA1, A2, B2, I2 and Thromboxan A2 were inactive in this regard.Histology showed that corneal neovascularization is always accompanied by the invasion of polymorphonuclear leukocytes. Corneal edema in the beginning of vascularization can be explai…