0000000001307896
AUTHOR
Amparo Navea
Ultraviolet radiation at Mediterranean latitudes and protection efficacy of intraocular lenses.
Summary Purpose After determining the mean intensity of ultraviolet radiation to which the human eye is exposed at Mediterranean latitudes, this data is used to evaluate the efficacy of the ultraviolet filters incorporated into various intraocular lenses. Methods Ultraviolet radiation measured at Mediterranean latitudes was used as a reference for the theoretical calculation of the amount of radiation to which the human eye is exposed. The spectral transmission curve from 290 to 380 nm was measured for 10 IOLs using a UV/VIS Perkins-Elmer Lambda 800 spectrometer. Results At Mediterranean latitudes, at sea level, with a mean annual solar irradiation of 50 j/cm 2 , the human eye receives a qu…
Genetic analysis of 2299delG and C759F mutations (USH2A) in patients with visual and/or auditory impairments
The most common mutation in the USH2A gene (Usherin), 2299delG, causes both typical Usher (USH) syndrome type II and atypical USH syndrome, two autosomal recessive disorders, characterised by moderate to severe sensorineural hearing loss and retinitis pigmentosa (RP). Furthermore, the C759F mutation in the USH2A gene has been described in 4.5% of patients with nonsyndromic recessive RP. We have investigated the presence of the 2299delG and/or the C759F mutations in 191 unrelated Spanish patients with different syndromic and nonsyndromic retinal diseases, or with nonsyndromic hearing impairment. The 2299delG mutation was observed in patients with clinical signs of USHII or of atypical USH sy…
Direct Objective Quantification of Corneal Haze after Excimer Laser Photorefractive Keratectomy for High Myopia
Purpose: The purpose of the study is to measure regional distribution differences in corneal haze after excimer laser photorefractive keratectomy for high myopia. Methods: The authors developed computerized gradient edge detectors with which were analyzed digitized anterior slit-lamp photographs of 40 eyes, an average of 21.0 plus or minus 14.5 weeks after photorefractive keratectomy for high myopia (−6 to −22 diopters). A treated area and an adjacent untreated area on the anterior corneal surface, each containing six regions, were quantified, and the difference was correlated with various parameters. Results: Mean differences between scarred and clear areas for haze grade 0.5, 1.0, 2.0, 3.…
Imaging Quality of Bifocal Piggyback Intraocular Lens versus ReSTOR and TECNIS Multifocal Lenses
Purpose The imaging quality provided by a piggyback integrated by a monofocal intraocular lens (IOL) + a bifocal IOL of zero power and +3.75 diopters of addition is compared with the optics quality of a simple multifocal IOL of the same power and addition. Methods The imaging quality was evaluated by determining the modulation transfer function (MTF), using an artificial eye simulating in vivo conditions of the anterior chamber, including an artificial cornea and a wet cell containing physiologic solution where the IOL was positioned. The MTFs of the bifocal piggyback for near and distance vision were measured, with pupil diameters of 3 and 5 mm, and compared with the MTFs of an equivalent …
Lipoic acid lessens Th1-mediated inflammation in lipopolysaccharide-induced uveitis reducing selectively Th1 lymphocytes-related cytokines release
AbstractInflammation results in the production of free radicals. We evaluated the anti-inflammatory and antioxidant capacity of lipoic acid in an experimental uveitis model upon a subcutaneous injection of endotoxin into Lewis rats. The role of oxidative stress in the endotoxin-induced uveitis model is well-known. Besides, the Th1 response classically performs a central part in the immunopathological process of experimental autoimmune uveitis. Exogenous sources of lipoic acid have been shown to exhibit antioxidant and anti-inflammatory properties. Our results show that lipoic acid treatment plays a preventive role in endotoxin-induced oxidative stress at 24 h post-administration and reduced…
Age‐induced change in the color of the human crystalline lens
Purpose To determine the chromatic coordinates of different human crystalline lenses to analyze the age-induced change in the color of the crystalline. Methods The spectral transmission of nine human crystalline lenses of different ages were measured by using a Perkin-Elmer 800 UV/VIS spectrophotometer. Using these data we calculated the chromatic coordinates of each crystalline lens for both solar and incandescent illumination. The study adheres to the tenets of the Declaration of Helsinki for Research Including Human Subjects and was approved by the Institutional Review Board. Results The results show a greater saturation of color with the increase of age. In principle, the change tends t…
Light transmission and ultraviolet protection of contact lenses under artificial illumination
Purpose: To determine the spectral transmission of contact lenses (CLs), with and without an ultraviolet (UV) filter to evaluate their capacity for protection under UV radiation from artificial illumination (incandescent, fluorescent, xenon (Xe) lamps, or white LEDs (light-emitting diode)). Methods: The transmission curves of nine soft CLs were obtained by using a PerkinElmer Lambda 35 UV-vis spectrophotometer. A CIE standard was used for the emission spectra of incandescent and fluorescent lamps, and Xe lamps and white LEDs were measured by using an International Light Technologies ILT-950 spectroradiometer. Results: Five of the nine soft CLs analysed state that they incorporate UV filters…
Use in clinical practice of an automated screening method of diabetic retinopathy that can be derived using a diagnostic artificial intelligence system
Resumen Antecedentes y objetivo Comparar el rendimiento diagnostico de un sistema de inteligencia artificial (IA) de diagnostico autonomo para el diagnostico de retinopatia diabetica derivable (RDR) con la clasificacion manual. Materiales y metodos Sujetos con diabetes tipo 1 y 2 participaron en un programa de cribado de retinopatia diabetica (RD) entre 2011-2012. Se recogieron dos imagenes de cada ojo. Se obtuvieron imagenes retinianas no identificables, una centrada en el disco y otra en la fovea. Los examenes se clasificaron con el sistema de IA autonomo y manualmente por parte de oftalmologos anonimos. Los resultados del sistema de IA y de la clasificacion manual se compararon en cuanto…
Spectral Transmission of the Human Crystalline Lens in Adult and Elderly Persons: Color and Total Transmission of Visible Light
Purpose To experimentally measure the spectral transmission of human crystalline lenses belonging to adult and elderly persons, and to determine the color and total transmission of visible light of such crystalline lenses. Methods The spectral transmission curve of 32 human crystalline lenses was measured using a PerkinElmer 800UV/VIS spectrometer. Total transmission of visible light and the chromatic coordinates of these crystalline lenses were determined from these curves for solar illumination. Results The crystalline lens that filters UV and its transmission in the visible spectrum decreases with age; such a decrease is greater for short wavelengths. The total transmission of visible li…
Excimer laser photorefractive keratectomy for high myopia
Abstract One hundred and thirty-three eyes of 103 patients had photorefractive keratectomy with a slit scan mode excimer laser for myopia ranging from −6.00 to −22.00 diopters (D). The epithelium was removed with 20% ethanol, and the ablation was done with a tapered profile surrounding the optical zone. Patients were divided into two groups based on preoperative myopia: Group A, −6.00 D to −12.00 D (88 eyes); Group B, −12.50 D to −22.00 D (45 eyes). In Group A, mean preoperative refraction was −9.59 ± 1.79 D. Mean postoperative refraction was −0.29 ± 1.47 D at one month, −0.85 ± 1.68 D at three months, −1.17 ± 2.04 D at six months, and −0.56 ± 0.74 D at one year. Anterior stromal haze was g…
Comparison of the acute effects of anti-TNF-alpha drugs on a uveitis experimental model.
To compare histopathological and biochemical effects of the anti-TNF-alpha drugs adalimumab and infliximab in a uveitis experimental model.Histopathological evaluation was performed 24 h after endotoxin (200 microg into the footpad) and drug administration, as well as biochemical analysis of oxidative stress-related markers in the aqueous humor.Severe inflammation was found in rat anterior chamber of the eye 24 h after endotoxin. Only infliximab administration partially prevented the endotoxin-induced disruption of the blood-aqueous barrier, as well as the increase in Rantes and MCP-1 concentration in aqueous humor. Both drugs ameliorated the histopathological score after endotoxin. Biochem…
Imbalance Between Oxidative Stress and Growth Factors in Human High Myopia.
Este artículo se encuentra disponible en la siguiente URL: https://www.frontiersin.org/articles/10.3389/fphys.2020.00463/full Myopia is one of the commonest eye pathologies that could affect 2.56 billion people by 2020. Today high myopia is a leading cause of blindness worldwide due to associated ocular illness. Nevertheless, the cellular bases for these diseases to develop are unclear in many areas. We conducted a prospective study of oxidative stress and growth factors in human myopic and non myopic eyes in an attempt to increase our understanding of the underlying physiopathological conditions to adequately early diagnose, prevent and treat the retina problem that derives from myopia. Aq…
An anti-interleukin-2 receptor drug attenuates T- helper 1 lymphocytes-mediated inflammation in an acute model of endotoxin-induced uveitis.
The aim of the present study was to evaluate the anti-inflammatory efficacy of Daclizumab, an anti-interleukin-2 receptor drug, in an experimental uveitis model upon a subcutaneous injection of lipopolysaccharide into Lewis rats, a valuable model for ocular acute inflammatory processes. The integrity of the blood-aqueous barrier was assessed 24 h after endotoxin-induced uveitis by evaluating two parameters: cell count and protein concentration in aqueous humors. The histopathology of all the ocular structures (cornea, lens, sclera, choroid, retina, uvea, and anterior and posterior chambers) was also considered. Enzyme-linked immunosorbent assays of the aqueous humor samples were performed t…
Reproducibility of digital image analysis for measuring corneal haze after myopic photorefractive keratectomy.
Purpose To evaluate the usefulness of digital image analysis for quantifying corneal haze by determining the reproducibility of its measurements at the corneal plane. Methods In a prospective study, 20 randomly selected eyes that had undergone myopic photorefractive keratectomy were photographed focusing the slit beam on their anterior corneal surface. Each photograph was examined using computer image analysis techniques that detect the edge of the reticular pattern of the image. Quantification of the difference between two areas, treated and adjacent untreated cornea, each containing 3,750 pixels with a resolution of 256 gray levels, was performed. Intra-analyzer variation was determined b…
Early lipoic acid intake protects retina of diabetic mice
The aim of this study was to test the effect of lipoic acid treatment on the retina after a short diabetic insult. Diabetes was induced by alloxan and mice were divided into sub-groups; control, diabetic, diabetic+insulin and all groups received+/-lipoic acid (100 mg/kg body weight) for 3 weeks. GSH content, MDA concentration, GPx activity were measured and electroretinograms (ERG) were recorded. Early administration of lipoic acid to diabetic mice prevented the statistically significant decreases of GSH content and GPx activity and normalized MDA concentration. Moreover, lipoic acid restored electroretinogram b-wave amplitude of diabetic animals to control values. Lipoic acid has a protect…
Spectral Transmittance of Intraocular Lenses under Natural and Artificial Illumination
Purpose To compare the spectral transmission of different intraocular lenses (IOLs) with either ultraviolet (UV) or blue-light filters, and to analyze the performance of these filters with artificial light sources as well as sunlight. Design Experimental study. Methods The spectral transmission curve of 10 IOLs was measured using a PerkinElmer Lambda 800 UV/VIS spectrometer (Waltham, MA). Different filtering simulations were performed using the D65 standard illuminant as daylight and standard incandescent lamp and fluorescent bulb illuminants. Main Outcomes Measures Spectral transmittance of the IOLs. Results All the IOLs studied provide good UVC (200–280 nm) and UVB (280–315 nm) protection…
Bevacizumab diminishes inflammation in an acute endotoxin-induced uveitis model
Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: https://www.frontiersin.org/articles/10.3389/fphar.2018.00649/full Introduction: Uveitis is an eye disease characterized by inflammation of the uvea and an early and exhaustive diagnosis is essential for its treatment. The aim of our study is to assess the potential toxicity and anti-inflammatory efficacy of Bevacizumab in an experimental uveitis model by subcutaneously injecting lipopolysaccharide into Lewis rats and to clarify its mechanism. Material and Methods: Blood–aqueous barrier integrity was assessed 24 h after endotoxin-induced uveitis (EIU) by analyzing two parameters: cell count and protein…
Spectral transmission of the pig lens: Effect of ultraviolet A+B radiation
Summary Objective To determine the spectral transmission curve of the crystalline lens of the pig. To analyse how this curve changes when the crystalline lens is irradiated with ultraviolet A + B radiation similar to that of the sun. To compare these results with literature data from the human crystalline lens. Procedures We used crystalline lenses of the common pig from a slaughterhouse, i.e. genetically similar pigs, fed with the same diet, and slaughtered at six months old. Spectral transmission was measured with a Perkin-Elmer Lambda 35 UV/VIS spectrometer. The lenses were irradiated using an Asahi Spectra Lax-C100 ultraviolet source, which made it possible to select the spectral emissi…
Mutation profile of the MYO7A gene in Spanish patients with Usher syndrome type I.
Usher syndrome type I is the most severe form of Usher syndrome. It is an autosomal recessive disorder characterized by profound congenital sensorineural deafness, retinitis pigmentosa, and vestibular abnormalities. Mutations in the myosin VIIA gene (MYO7A) are responsible for Usher syndrome type 1B (USH1B). This gene is thought to bear greatest responsibility for USH1 and, depending on the study, has been reported to account for between 24% and 59% of USH1 cases. In this report a mutation screening of the MYO7A gene was carried out in a series of 48 unrelated USH1 families using single strand conformation polymorphism analysis (SSCP) and direct sequencing of those fragments showed an abnor…
Liposomally-entrapped ganciclovir for the treatment of cytomegalovirus retinitis in AIDS patients
Treatment of retinitis by cytomegalovirus (CMV) in AIDS patients requires frequent repetitive injections of intravitreal ganciclovir (GCV). This study was undertaken to establish experimentally whether the intravitreal application of liposomally-entrapped GCV could prolong intraocular therapeutic levels when compared with the intravitreal injection of free GCV, and the clinical effectiveness of this approach in AIDS patients. Intraocular concentration of GCV was determined by means of an ELISA test in rabbit vitreous 2, 3, 7, and 14 days after a single intravitreal injection of either different doses of the free drug (0.2-20 mg) or 1 mg of liposomally-entrapped GCV. After 72 h, only the vit…
Use in clinical practice of an automated screening method of diabetic retinopathy that can be derived using a diagnostic artificial intelligence system
Abstract Background and Objective To compare the diagnostic performance of an autonomous diagnostic artificial intelligence (AI) system for the diagnosis of derivable diabetic retinopathy (RDR) with manual classification. Materials and Methods Patients with type 1 and type 2 diabetes participated in a diabetic retinopathy (RD) screening program between 2011–2012. 2 images of each eye were collected. Unidentifiable retinal images were obtained, one centered on the disc and one on the fovea. The exams were classified with th e autonomous AI system and manually by anonymous ophthalmologists. The results of the AI system and manual classification were compared in terms of sensitivity and specif…
Bacterial Contamination of Anterior Chamber Fluid Following Non-complicated Cataract Surgery
Objective: To study the anterior chamber contamination during non-complicated cataract surgery and its relationship with normal conjuctival organisms. Setting: Ophthalmology Department, La Fe Hospital, University of Valencia. Patients: Forty patients who had undergone cataract extraction using either ECCE, phacoemulsification or nucleus fracture methods. Results: Positive cultures of aqueous humour were obtained in 32.5% of cases. The most commonly isolated organism was Staphylococcus coagulase-negative. Only in 7.7% of cases was the microorganism found in the conjunctiva the same as that found in the anterior chamber. The inoculum size ranged between 20 and 160 colonies/ml. One of the case…
The influence of storage method on the transparency of pig crystalline lens
Este artículo se ha publicado de forma definitiva en: http://www.scielo.br/pdf/abo/v82n1/0004-2749-abo-82-01-0056.pdf Purpose: The porcine eye is frequently used as a research model. This paper analyzes the effect of different storage methods on the transparency of pig crystalline lens. Methods: A spectral transmission curve (from 220 to 780 nm) for the crystalline lens was determined experimentally after storage in different conditions: saline solution, formalin, castor oil, and freezing at -80°C. The total transmission in the visible spectrum, which was used as an index of transparency, was calculated from these curves. For comparative purposes, fresh lenses were evaluated and used as con…
Intravitreal foscarnet for cytomegalovirus retinitis in a patient with acquired immunodeficiency syndrome.
We treated a patient who had acquired immunodeficiency syndrome and cytomegalovirus retinitis of the left eye. After anesthetic had been topically administered, the patient received intravitreal injections of 1,200 micrograms of foscarnet. Plasma and vitreous foscarnet levels were measured by high-performance liquid chromatography. Systemic absorption of the drug was not evident. Elimination half-life from the vitreous after one injection was 54.0 hours. Vitreous levels remained above the mean 50% inhibition value for cytomegalovirus for approximately 56 hours and above the mean inhibition value for human immunodeficiency virus for approximately 241 hours. The patient's visual acuity improv…
Clinical magnification and residual refraction after implantation of a double intraocular lens system in patients with macular degeneration
Purpose To evaluate the efficacy of a standard double intraocular lens (IOL) system (IOL-Vip) in patients with low vision and central scotoma due to macular degeneration and assess the predictability of the residual refraction and magnification. Setting Ophthalmology Department, Hospital General Universitario, Valencia, Spain. Methods This interventional prospective noncomparative case series comprised 13 consecutive surgical procedures in 10 patients with central scotoma. Follow-up was 12 months. Evaluation included the difference between preoperative and postoperative best corrected visual acuity (BCVA), refraction, position of the IOLs, endothelial cell density, and occurrence of postope…
Determination of scattering in intraocular lenses by spectrophotometric measurements.
This study presents a method for measuring scattering in explanted intraocular lenses (IOLs). Currently, determining scattering in IOLs is usually performed by Scheimpflug cameras and the results are expressed in the units used by this apparatus. The method we propose uses a spectrophotometer and this makes it possible to measure the total transmission of the IOL by using an integrating sphere; the direct transmission is determined by the double-beam mode. The difference between these two transmissions gives a value of the scattering in percentage values of light lost. In addition, by obtaining the spectral transmission curve, information about the most scattered wavelengths is also obtaine…
Validation of Automated Screening for Referable Diabetic Retinopathy With an Autonomous Diagnostic Artificial Intelligence System in a Spanish Population
Purpose: The purpose of this study is to compare the diagnostic performance of an autonomous artificial intelligence (AI) system for the diagnosis of referable diabetic retinopathy (RDR) to manual grading by Spanish ophthalmologists. Methods: Subjects with type 1 and 2 diabetes participated in a diabetic retinopathy (DR) screening program in 2011 to 2012 in Valencia (Spain), and two images per eye were collected according to their standard protocol. Mydriatic drops were used in all patients. Retinal images—one disc and one fovea centered—were obtained under the Medical Research Ethics Committee approval and de-identified. Exams were graded by the autonomous AI system (IDx-DR, Coralville, Io…
Diclofenac sodium and cyclosporin A inhibit human lens epithelial cell proliferation in culture.
• Purpose: To investigate the effect of diclofenac sodium salt and cyclosporin A (CsA) on human lens epithelial cell (HLEC) growth in culture. • Methods: Cultures of HLEC were obtained from anterior capsules from extracapsular cataract surgery. Third-passage cells were seeded in 96-well plates in 0.1 ml culture medium. Cytotoxicity was estimated by the tetrazolium test in confluent monolayers after 24 h exposure to a wide range of concentrations of diclofenac and CsA. The effect of subcytotoxic concentrations of diclofenac and CsA on HLEC proliferation in subconfluent cultures was evaluated after 24 and 72 h of exposure. To investigate the relationship between PGEZ synthesis and the inhibit…
Optical analysis to predict outcomes after implantation of a double intraocular lens magnification device.
Purpose To analyze the effect of different optical parameters of the eye on the outcomes of implantation of a double intraocular lens (IOL) magnification device in patients with low vision. Setting Fundacion Oftalmologica del Mediterraneo, Valencia, Spain. Methods The eye's refraction and magnification before and after surgery were evaluated using a theoretical eye model based on paraxial optics approximation. Four parameters on which refraction and magnification are dependent were evaluated: anterior chamber depth (ACD), axial length (AL), mean keratometry (Km), and the distance between the 2 implanted IOLs. The 4 variables were analyzed separately in the first stage. Next, different combi…
A rapid method for measuring intraocular lens power in vitro with a focimeter.
In this paper we describe a new method for measuring the intraocular lens (IOL) power using a focimeter, a negative ophthalmic lens and a saline solution (0.9% NaCl). To test this we measured the power of 58 different IOLs and we compared them with the power stated by the manufacturer. Despite the limitations, the results show a good correlation.
Intravitreal injection of bevacizumab induces inflammatory alterations in a uveitis experimental model.
PurposeBevacizumab is currently used as an intravitreal agent in the treatment of inflammatory-associated eye diseases. The aim of the current study is to explore the effects of the intravitreal injection of bevacizumab on aqueous humour cytokines and chemokines in an experimental uveitis model.MethodsEndotoxin-induced uveitis was induced in rats by footpad injections. Bevacizumab was administered by intravitreal injection (75 μg in 3–μL samples) and different chemokine and cytokine proteins were quantified in aqueous humor.ResultsIntravitreal administration of bevacizumab led to a several-fold increase of RANTES, MCP-1, and IFN-γ concentrations in aqueous humor of endotoxin-treated rats.Co…
Photoprotection and photoreception of intraocular lenses under xenon and white LED illumination.
Objective. To analyze the photoprotection and phototransmission that various intraocular lenses (10Ls) provide under the illumination of a xenon (Xe) lamp and white LEDs (light emitting diode). Methods. The spectral transmission curves of six representative 10Ls were measured using a Perkin-Elmer Lambda 35 UV/VIS spectrometer. Various filtering simulations were performed using a Xe lamp and white LEDs. The spectral emissions of these lamps were measured with an ILT-950 spectroradiometer. Results. The 10Ls analyzed primarily show transmission of nearly 100% in the visible spectrum. In the ultraviolet (UV) region, the filters incorporated in the various 10Ls did not filter equally, and some o…
The influence of storage method on the transparency of pig crystalline lens
ABSTRACT Purpose: The porcine eye is frequently used as a research model. This paper analyzes the effect of different storage methods on the transparency of pig crystalline lens. Methods: A spectral transmission curve (from 220 to 780 nm) for the crystalline lens was determined experimentally after storage in different conditions: saline solution, formalin, castor oil, and freezing at -80°C. The total transmission in the visible spectrum, which was used as an index of transparency, was calculated from these curves. For comparative purposes, fresh lenses were evaluated and used as controls. Results: Storing the porcine crystalline lens in saline solution or castor oil resulted in a transpare…