Person: Pérez Carrasco, María Jesús
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First Name
María Jesús
Last Name
Pérez Carrasco
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Óptica y Optometría
Department
Optometría y Visión
Area
Optica
Identifiers
14 results
Search Results
Now showing 1 - 10 of 14
Item New Optical Filter Plate for Use as Eye Protection by Welders(Welding journal, 2013) Langa Moraga, Antonio; Bonnin Arias, Cristina Natalia; Chamorro, Eva; Pérez Carrasco, María Jesús; Sánchez Ramos, CeliaPeople whose work tasks involve the use of welding torches are at special risk of suffering eye injuries due to the emission of visible, short-wavelength radiation. Current legislation requires that a company provide its employees with protection against the harmful radiation produced by welding equipment. Often, however, a worker will be reluctant to use protective goggles since these markedly cut visibility and can consequently lead to errors or even burns. This practice of avoiding the use of protection makes them susceptible to suffer irreversible severe retinal damage leading to partial or complete loss of vision. In this paper, we propose the use of a new photoprotective filter in the form of safety goggles that seeks to improve the compromised vision produced by conventional filters. We compare a series of visual function variables in 36 adults, aged 30 to 58 years, using the new optical filter and a conventional filter used for welding protection. Our findings suggest that the filter proposed provides optimal protection against the harmful effects of short-wavelength radiation while minimizing the reduced vision effects of conventional filters used for this purpose.Item Effect of a yellow filter on mesopic contrast perception and differential light sensitivity in the visual field.(Ophthalmic Research, 2003) Pérez Carrasco, María Jesús; Puell Marín, María Cinta; Sánchez Ramos, Celia; Langa Moraga, AntonioPurpose: Previous studies on the effects of yellow filters in the visual performance have been carried out, presenting discrepancies among the different investigations. Our study reports the influence of the yellow filter without residual reflections on contrast perception and differential light sensitivity (DLS) under mesopic conditions. Methods: Contrast sensitivity, low contrast visual acuity and luminance thresholds in the central visual field (30 degrees ) were measured in a group of 38 adult subjects with and without a coated yellow lens (482-nm cut-off) under mesopic conditions. Results: The contrast sensitivity mean was significantly better with the filter at low- and middle-range spatial frequencies (1.5 cycles/degree p = 0.002 and 6 cycles/degree p = 0.02). At 5% contrast, the mesopic low contrast visual acuity improved significantly (p = 0.004) when interposing the yellow filter. The increase in DLS was statistically significant [e.g. all visual fields p = 0.0003 and macular visual field (9.5 degrees ) p = 0.00001] through the yellow filter on the different established areas of the visual field (30 degrees ). Conclusions: The yellow filter without residual reflections had a positive influence on the brightness and contrast perception of healthy subjects, for which its use would be beneficial under mesopic conditions.Item Nuevo instrumento para medir la sensibilidad al contraste sin y con deslumbramiento(Archivos de la Sociedad Española de Oftalmología, 2003) Sánchez Ramos, Celia; Puell Marín, María Cinta; Pérez Carrasco, María Jesús; Langa Moraga, Antonio; Benítez Del Castillo Sánchez, José ManuelOBJETIVO/MÉTODO: valorar la sensibilidad al contraste fotópica, sin y con deslumbramiento con un nuevo instrumento. Se estudiaron 78 ojos derechos de 49 adultos jóvenes y de 29 adultos entre 35 y 55 años. La sensibilidad al contraste se midió con el Contrast Glarester CGT-1000 mediante una estrategia automatizada de reconocimiento para seis frecuencias espaciales. RESULTADOS/CONCLUSIONES: Los valores de sensibilidad al contraste fueron semejantes a los obtenidos con otros test clínicos. El aumento de la edad disminuyó significativamente la sensibilidad al contraste sin y con deslumbramiento. Sin embargo, el deslumbramiento no modificó la sensibilidad al contraste fotópica.Item Efectividad de los filtros polarizados frente a los coloreados en la Sensibilidad al Contraste bajo condiciones de deslumbramiento central por reflexión.(Ver y Oír, 2008) Sillero, Manuel; Moral Martinez, Inmaculada; Langa Moraga, Antonio; Pérez Carrasco, María Jesús; Sánchez Ramos, CeliaLa efectividad de los filtros polarizados frente al deslumbramiento central por reflexión ha sido demostrada sólo mediante test empíricos de laboratorio, pero no desde el punto de vista fisiológico. En este trabajo se midieron, en 96 sujetos adltos de un amplio rango de edad, los efectos del deslumbramiento central por reflexión y en ausencia de él, con filtros polarizados, filtros coloreados y sin filtros, utilizando un protocolo original próximo a las condiciones de la vida real. La aproximación ecológica confirma que los filtros polarizados son significativamente más efectivos que los coloreados frente al deslumbramiento central por reflexión.Item Effect of Mesopic/Scotopic Luminance on Pupil Diameter and Anisocoria in Drivers Over 65 Years of Age(2005) Pérez Carrasco, María Jesús; Sánchez Ramos, Celia; Moral Martínez, M.I.; Puell Marín, María Cinta; Langa Moraga, AntonioPurpose: To evaluate the changes produced in pupil diameter and anisocoria in mesopic and scotopic conditions in subjects over the age of 65 years. Methods: A prospective evaluation was performed of pupil diameter in 45 motor car drivers aged 65 to 80 years (69±6 years). Measurements were made using an infrared, binocular pupillometer P2000 (Procyon Instruments Ltd) at 3 luminance levels: 0.04 lux (scotopic), 0.4 lux (low mesopic) and 4 lux (high mesopic). For each measurement, 10 photographs of both eyes are automatically taken by the instrument. Results: In scotopic conditions, mean pupil sizes were RE 5.37±1.1 mm, LE 5.29±1 mm. When the luminance level was increased to 0.4 lux (low mesopic conditions) mioses of 18% and 17%, respectively for the right and left eyes, were observed, resulting in pupil diameters of RE 4.55±0.83 mm, LE 4.51±0.78 mm. In high mesopic conditions (4 lux), pupil diameters were RE 3.47±0.60 mm, LE 3.41±0.89 mm, corresponding to mioses from the previous luminance level of 28% and 29%, respectively. The diferences in pupil diameter among the three luminance levels were significant. No diferences attributable to the luminance level were detected between each eye. The degrees of anisocoria observed were 5.77%, 5.78% and 5.77% in scotopic, low and high mesopic conditions, respectively. No significant diferences in scotopic/mesopic pupil sizes were revealed when the population was divided into three (15–year) age groups, or according to sex. Conclusions: At scotopic and mesopic luminance levels, drivers over 65 years show significant diferences in pupil diameter but no changes in anisocoria.Item Mesopic contrast sensitivity and glare disability in drivers.(2003) Sánchez Ramos, Celia; Puell Marín, María Cinta; Pérez Carrasco, María Jesús; Langa Moraga, Antonio; Benítez Del Castillo Sánchez, José ManuelVisual Acuity is a poor predictor of driving ability and it is likely to be a poor predictor of many aspects of real-world vision, because the real world is not composed purely of fine objects with sharp edges at high contrast. Although not all objects are at contrst treshold either, it has been shown that a loss of contrast sensitivity (CS) is roughly equivalent to a loss of image contrast in the normal eye (OWSLEY, 1994). The extent of contrast loss required before real-world performance is reduced depends on the real-world task being performed. Somo tasks, such as optimal speed reading and mobility orientation in a well-llit room, tolerate large reductions in contrast (Elliot, 1996; Leffe, 1993; Pelli, 1986). These tasks would probably only be affected in patients with a severe loss of contrast sensitivity. However, other tasks such as speed reading newspaper-size print and face recognition are moderately affected by contrast reduction (Elliot, 1996). Further, mobility orientation under dim illumination has been shown to be seriously affected by reduced contrast. Thus, under low-iluminance conditions and when a subject is working near his or her acuity limit, tolerance to contrast loss is reduced (Legge, 1993)Item Age effects on mesopic and scotopic anisocoria determined in vehicle drivers.(2005) Sánchez Ramos, Celia; Puell Marín, María Cinta; Pérez Carrasco, María Jesús; Langa Moraga, Antonio; Moral Martínez, M.I.The diameter of the pupil affects a person´s vision in a complex manner. As the pupil dilates, it allows more light to enter the eye and stimulate the retina, reducing blur caused by diffraction to a minimum. A narrow pupil, on the other hand, reduces the negative effects of these aberrations on the crystaline lens. In general, a pupil diameter of 3 to 6 mm increases clarity of vision. Owing to the adaptation process, humans can tolerate a difference in luminance conditions from 1 to 10000000 cd/m2. The spectrum of visual sensitivity is so broad that in a graph, the intensity of light has to be plotted on a logarithmic scale.Item Straylight in older drivers.(2009) Sánchez Ramos, Celia; Colilla, E.A.; Gómer Tortuero, E.; Langa Moraga, Antonio; Pérez Carrasco, María JesúsThe measures of the dazzle and of the dispersion of the light intraocular are particularly important for the drivers and affected subjects of cataracts. The technology of measure of the strylight values the dispersion of the light for psycophysical methods allos to know the state of the visual function of olders drivers. The aim is to evaluate de validity of the measure of the dispersion of the light intraocular as enough indicator to determine the visual capacity of the drivers´s in conditions mesópica.Item Características funcionales y ergonómicas de las lentes ocupacionales.(2005) Sánchez Ramos, Celia; Moral Martínez, M.I.; Alonso Fernández, José; Puell Marín, María Cinta; Langa Moraga, Antonio; Pérez Carrasco, María JesúsEl propósito de este trabajo ha sido evaluar tanto objetiva como subjetivamente las características ergonómicas y funcionales de las lentes ocupacionales, comparándolas con las lentes monofocales convencionales. Esta evaluación se ha realizado con pruebas psicofísicas como sensibilidad al contraste, agudeza visual de contraste variable, y perimetría FDT, además de con un cuestionario subjetivo. La muestra ha estado compuesta por 30 pacientes con edades comprendidas entre 40 y 58 años. Las conclusiones indican que tanto objetiva como subjetivamente se obtienen diferencias por el uso de las lentes ocupacionales.Item Agudeza visual Snellen versus agudeza visual medida por interferencia.(1996) Langa Moraga, Antonio; Sánchez Ramos, Celia; Puell Marín, María Cinta; Pérez Carrasco, María JesúsLos test de interferencias para la agudeza visual permiten la función macular con independencia del estado del sistema óptico ocular, siendo de gran inte´res por ser un método objetivo, además de ser útil cuando los medios oculares presentan opacidades. Nuestro objetivo es investigar en población joven universitaria la relación existente entre los valores de agudeza visual obtenidos con la E de Snellen y los obtenidos con el IRAS GT 761, con objeto hacer una valoración de este nuevo método de medida y evaluar la posible pérdida de agudeza visual debida al sistema óptico.