Person:
Pérez Carrasco, María Jesús

First Name

María Jesús

Last Name

Pérez Carrasco

URI

https://hdl.handle.net/20.500.14352/79893

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Óptica y Optometría

Department

Optometría y Visión

Area

Optica

Identifiers

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Now showing 1 - 10 of 36

Effect of a yellow filter on mesopic pupil size.
(2004) Sánchez Ramos, Celia; Puell Marín, María Cinta; Langa Moraga, Antonio; Pérez Carrasco, María Jesús; Jiménez, I.; Pelaez, T.
PURPOSE: It has been recently reported that pupil size is independent of the wavelength for adapting luminances from photopic to mesopic. Herein, we tried to determine whether blue-blocking filters really increase pupil size, as has been reported previously, in an effort to establish if this type of lens has any effect on vision at night when blue takes on much greater importance. METHODS: Mesopic pupil size was measured in 62 eyes of 31 healthy subjects (mean age 37 +- 13 years) using the digital (Procyon 2000) infrared pupillometer for binocular simultaneous measurements of pupil diameter. Measurements were performed at a low mesopic illuminance level (0.40luz) after 5 min of dark adaptation and while the observer viewed through a yellow coated filter (X-482nm cut-off), through a neutral density (ND) filter, or no filter. RESULTS: For righ eyes, mean mesopic pupil diameter was 6.05+-1.41mm (range 3.05-8.17mm) with the yello filter, 5.97+-1.37mm (range 3.01-8.15mm) with the ND filter, and 5.87+-1.30mm (range 3.02-8.28mm) without a filter. No significant differences were shown between the pupil sizes of both eyes. No pupil size differences were detected whether a filter was used or not, nor when the population was divided into three age groups. CONLCUSIONS: The yellow filter has no effect on pupil size under mesopic luminance conditions. Accordingly, its use would not compromise visual quality at night.
Influencia del hábito de conducción en la sensibilidad al contraste mesópica sin y con deslumbramiento.
(2004) Elena Tirado, María José; Puell Marín, María Cinta; Langa Moraga, Antonio; Pérez Carrasco, María Jesús; Sánchez Ramos, Celia; Martínez de Miguel, María Angeles; Agustín Gonzálo, Monica; Vicente González, Eva
La sensibilidad al contraste (SC) se relaciona en algunos estudios con la capacidad de conducción, además dicha capacidad se puede ver reducida en condiciones de baja iluminación. Nuestros objetivos fueron valorar la SC mesópica- sin y con deslumbramiento- en conductores de vehículos de mediana edad y analizar el efecto del hábito de conducción.
Agudeza visual Snellen versus agudeza visual medida por interferencia.
(1996) Langa Moraga, Antonio; Sánchez Ramos, Celia; Puell Marín, María Cinta; Pérez Carrasco, María Jesús
Los 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.
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 Manuel
OBJETIVO/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.
Effects of age and the retinal zone stimulated on differential luminance sensitivity in vehicle drivers over 65 years.
(2004) Vila, J.; Moral Martinez, M.I.; Sánchez Ramos, Celia; Puell Marín, María Cinta; Pérez Carrasco, María Jesús; Pérez Pérez, J.M.
PURPOSE: To evaluate central visual field (30º) differential luminance sensitivity (DLS) in drivers over the age of 65 years and compare responses according to the zone of the retina stimulated and age. METHODS: DLS was determined under photopic conditions (85 cd/m2) in 62 subjects (right eye) using a Humphrey model HFA-II 730 campimeter (Zeiss) to perform the STACTPAC technique with Goldamnnis stimulus III. Test were conducted with habitual correction for near vision. RESULTS: The mean age of our population sample was 72.5 +- 5.4 year (85% men/15% women). Mean visual acuity was 0.82+-0.14. The mean spherical power of the lenses was +0.93 +- 1.87D and cylindrical power -0.87+-1.63D. Mean added power was 2.42+-0.59D. Mean DLS was 27.01+-2.52dB. Values by retinal zone were 30.32 +-2.35 dB (foveal) 28.77 +-2.50dB (parafoveal), and 26.14 +-2.76 dB (peripheral). When the simple was stratified by age (older or younger than 70 years), significant differences in DLS were obteined for the four quadrants and the different retinal zones. CONCLUSION: Mean DLS values for the drivers differed significantly among the foveal, parafoveal and peripheral zones of the retina, with measurements made at the fovea being significantly higher. In drivers above 65 years, age showed a negative effect on DLS in all the retinal zones examined.
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 Jesús
El 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.
Increase of the spatial resolution and of the contrast sensitivity for myosis induced in usual drivers demonstrates experimentally.
(2009) Sánchez Ramos, Celia; Langa Moraga, Antonio; Gómez Tortuero, E.; Pérez Carrasco, María Jesús; Colilla, E.
Human visual system is able to adapt itself to get better visual perception in a very extense lighting range, since light of the moon until brilliant sunlight, so from scotopic until photopic lighting (Walkey and Barbur, 2006). Changes in pupil size produced in response to changes in light intensity optimise the amount of light received by the retina, maximizing visual perception. This is produced along 10 log units, thanks to the human eye adaptation by biochemical and nervous mechanisms. In the light/darkness process of adaptation mechanical activity, due to pupil size variations (Myosis/mydriasis), contributes 1 logarithmic unit and is the most rapid of all contributions to the response. Between both lighting limits (photopic and scotopic), mesopic range is establised. This lighting (mesopic) is found in a natural way when night falls or at dawn, time in which driving becomes a harder task, thus its study has such an enormous interest due to its influence of driving. Mesopic vision describes the period of trnsition from rods (Scotopic) until cones (photopic) vision, in which both photoreceptors contributes to the visual response. Although it hasn´t been precisely establised by the CIE (Commission Internationale de l´Eclairage), mesopic range covers roughly 4 log units (Wyszecky y Stiles 1982; Walkey et al. 2006), which means lighting levels frecuently used in occupational ambient. In mesopic lighting condition several changes are produced in visual function. Pupil size variations distort the optic of the eye, degrading the quality of the retinal image (aberrations and light dispersion). On the other hand, the extensive spatial summation of the rods signal increases the light sensitivity but also causes a significant lost of contras sensitivity, the visual acuity of low contrast and the spatial resolution (Walkey y Barbur, 2006).
Contrast sensitivity and disability glare in patients with dry eye
(Acta Ophthalmologica Scandinavica, 2006) Puell Marín, María Cinta; Benítez Del Castillo Sánchez, José Manuel; Martínez De La Casa Fernández-Borrella, José María; Sánchez Ramos, Celia; Aladro Vico, Eva; Pérez Carrasco, María Jesús; Pedraza Aranda, Constanza; Hierro Zarzuelo, Almudena, del
Purpose: To evaluate contrast sensitivity and disability glare in patients with dry eye using the Contrast Glaretester 1000. Methods: Contrast sensitivity and disability glare were determined in 33 eyes of 33 patients with dry eye and 30 eyes of 30 healthy control subjects for six target sizes with a visual angle of 6.3-0.7 degrees using the Contrast Glaretester 1000, whose working mechanism is similar to that of the conventional perimetry instrument. Results: Contrast sensitivity was significantly worse in dry eye group when viewing all target sizes (reduction of 0.10-0.25 log contrast units, p < 0.01) except at 6.3 degrees. In the presence of glare, differences in log contrast sensitivity between the groups (0.10-0.25 units) were significant (p < 0.01) for all target sizes, with the dry eye group showing worse results. The reduction in contrast sensitivity induced by glare (disability glare) was significantly worse in the dry eye group versus the control group but only for the 2.5-degree size target, where 0.14 log contrast units were lost. Conclusions: Contrast sensitivity with and without glare was significantly reduced in patients with dry eye compared with control subjects, but the number of log contrast units lost with glare (disability glare) was similar in the two groups, except for the 2.5-degree size target.
Effect of the discrimination of movement objects on the contrast sensitivity for frequency doubling technology.
(2002) Pérez Carrasco, María Jesús; Sánchez Ramos, Celia; Puell Marín, María Cinta; Langa Moraga, Antonio
Enhancing contrast sensitivity with polarized filter in sports with glare produced on flat surfaces under photopic conditions.
(2007) Sillero, M.; Langa Moraga, Antonio; Moral Martínez, I.; Pérez Carrasco, María Jesús; Sánchez Ramos, Celia
INTRODUCTION: Reflections of light on flat surfaces foten generate central glare during sport practice (i.e. skiing, fishing or driving). Polarized filters are mounted in googles or spectacles to neutralize the effects of glare on these situations, but only empiral data from the manufactures and subjective evaluations probe the ffectiveness of polarized filters under reflected glare on flat surfaces. There is a lackk of information in literature about physiological effects of polarized filters on vision. METHODS: 52 physically active subjects (40 males and 12 female; 22.16 +- 6.89 years) with normal vision (Visual Acuity Snellen coefficient= 1.08 +-0.28) performed the test, seated with their head placed on a chin-rest located 1.76 meters away from a Pelli-Robson contrast sensitivity chart, which was placed on the floor. In order to generate the central glare, we projected a collimated light bearn onto the chart. Binocular contras sensitivity was recorded with the subject wearing spectacles fifted with a standard polarized filter, with coloured filter- both of them with the same transmitance- and without filter. The dazzling light hit the test surface first at an angle of 31.5º with respect to the horizontal (Brewster angle) and then at 46.6º, 37.6º, 23.8º and 17.2º. Both the visual an angle conditions were randomized to avoid glare, tiredness and memorization effects on the results. RESULTS: results show how the effect of glare was neutralized by the polarized filter- with values close to reference levels recorded without glare- but not by the coloured filter, which gave rise to similar contrast sensitivities as for the uncovered eyes. The benefits of polarized filters were reduced- but were still significant in all the cases- as the angle of incident light was varied from the Brewster angle. DISCUSION: Our ecological approach achieved controlled yet realistic, polarized reflected central glare on the test surface, which prevented subjects from properly seeing the target. This scenario difered from most reports in the literature, in which glare is generated by a diffuse light source, escentric to the test target. Our results probe by fist time, in physiologically terms, the benefits of using polarized filters to improve contrast sensitivity in the presence of glare produced on horizontal sufaces under photopic light conditions.