Search results for "cornea"
showing 10 items of 404 documents
Evaluation of 6 biometers based on different optical technologies
2021
This study shows that optical biometers based on different technologies provide repeatable measurements for different ocular parameters and, when compared, statistically significant differences between them were found when measuring most parameters.
Changes in meibomian fatty acids and ocular surface in patients with meibomian gland dysfunction after minocycline treatment
2008
International audience; Purpose:Tear film lipid layer (TFLL) is a very structured layer with essential functions. Its structure is highly dependent on chemical and physical characteristics of lipids composing the TFLL We previously published alterations in the composition of TFLL in patients suffering from meibomian gland dysfunction (MGD). Branched chain fatty acids (BCFA) were significantly increased, suggesting that BCFA may be associated with the disease. The aim of this study was to evaluate the effect of a treatment by oral minocycline associated to lid hygiene versus lid hygiene only on changes in ocular surface abnormalities and in meibomian fatty acid composition in patients suffer…
Lentes de contacto rígidas permeables al gas corneo-esclerales de alto Dk en la rehabilitación visual de pacientes con queratocono
2017
INTRODUCCIÓN Las ectasias corneales son distrofias progresivas que afectan a la morfología corneal, provocando alteraciones funcionales debido a que inducen una forma cónica irregular, disminuyendo la visión de los pacientes. El queratocono es una ectasia corneal que provoca aberraciones de alto orden que empeoran la calidad de visión, especialmente en los casos donde la enfermedad está más desarrollada. De entre todos los tratamientos actuales, la cirugía con implante de anillos intracorneales intenta eliminar la deformidad de la córnea para mejorar la agudeza visual. Los resultados visuales tras la cirugía en unos casos son satisfactorios, en cambio, en otros, los pacientes no quedan sati…
Polyphosphate, the physiological metabolic fuel for corneal cells: a potential biomaterial for ocular surface repair
2019
The regeneration of the epithelium, covering the avascular cornea, involves the processes of differentiation, proliferation and migration of cells originating from the corneal epithelial stem cells. We ask the question if these energy-consuming processes can be fueled by the physiological, inorganic polyphosphate (polyP), the main energy storage/donor molecule in the extracellular space. The ex vivo results reveal that addition of polyP, in the form of soluble Na-polyP, to the culture medium elicits a strong stimulatory effect on cell viability/growth and migration of corneal epithelial cells. Microscopic analyses of partially denuded cornea specimens show that in the presence of polyP, but…
Utilization of metabolic energy in treatment of ocular surface disorders: polyphosphate as an energy source for corneal epithelial cell proliferation.
2019
Impaired regeneration of the corneal epithelium, as found in many ocular surface diseases, is a major clinical problem in ophthalmology. We hypothesized that corneal epithelial regeneration can be promoted by the physiological, energy-delivering as well as “morphogenetically active” polymer, inorganic polyphosphate (polyP). Corneal limbal explants (diameter, 4 mm) were cultivated on collagen-coated well plates in the absence or presence of polyP (chain length, ∼40 Pi units; 50 μg ml−1) or human platelet lysate (hp-lysate; 5% v/v). Cell outgrowth and differentiation were analyzed after staining with DRAQ5 (nuclei) and rhodamine phalloidin (cytoskeleton), as well as by environmental scanning …
Tributo al professor Miguel F. Refojo, PhD, DSc (1928---2016)
2016
[Excerpt] July 21, 2016, Professor Miguel F. Refojo passed away at the age of 88 in Needham (Massachusetts). Saying that Miguel was one of the most renowned Spanish scientists of the second half of the XXth Century does not resembles its actual scientific size. Indeed, Miguel (or “Migüel” as most of his American friends pronounced his name) was a World Class scientist and inventor that will be forever linked to the advances in polymer science applied to the ophthalmic environment. His contributions in the biomedical field start “officially” in 1967 according to the National Library of Medline database (Pubmed-Medline). [...]
“In situ” corneal and contact lens thickness changes with high resolution OCT
2012
Purpose: To show the utility of high resolution spectral domain optical coherence tomography (HR SOCT) for the in situ evaluation of epithelial, stromal and contact lens (CL) thickness changes under closed-eye conditions without lens removal. Settings: Clinical and Experimental Optometry Research Lab, University of Minho, Portugal. Methods: Eight young healthy patients wore a thick soft CL during 90 minutes under closed-eye conditions and measures of epithelial and stromal corneal thickness were obtained at regular intervals using a HR SOCT (Copernicus HR, Optopol Tech. SA, Poland). Results: Minimal changes in epithelial thickness were detected with a transient statistically significant inc…
Early and late clinical landmarks of corneal dystrophies
2020
Abstract Corneal dystrophies (CDs) represent a heterogenous group of genetic diseases (Lisch and Weiss, 2019). The International Committee of Classification of Corneal Dystrophies (IC3D) distinguishes between 22 distinct forms of corneal dystrophy (CD) which are predominantly autosomal dominant, although autosomal recessive and X-chromosomal dominant and recessive patterns do exist. A detailed corneal examination of as many affected family members as possible can show the phenotypic differences of the various generations. There are few publications which describe the different CDs with regard to the early and late phenotypes. According to early and late phenotype, three types of CD are gene…