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
19 results
Search Results
Now showing 1 - 10 of 19
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 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, delPurpose: 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.Item Impaired Mesopic Visual Acuity in Eyes with Early Age-Related Macular Degeneration(Investigative Ophthalmology and Visual Science, 2012) Puell Marín, María Cinta; Barrio De Santos, Ana Rosa; Palomo Álvarez, Catalina; Gómez Sanz, Fernando J.; Clement Corral, Amaya; Pérez Carrasco, María JesúsPurpose.: To determine photopic and mesopic distance high-contrast visual acuity (HC-VA) and low-contrast visual acuity (LC-VA) in eyes with early age-related macular degeneration (AMD). Methods.: Measurements were made in 22 subjects with early AMD and 28 healthy control subjects. Inclusion criteria included a photopic HC-VA of 20/25 or better. Distance VA was measured using HC (96%) and LC (10%) Bailey-Lovie logMAR letter charts under photopic (85 cd/m2) and mesopic (0.1–0.2 cd/m2) luminance conditions. Results.: Mean mesopic distance HC-VA and LC-VA were significantly worse (0.1 logMAR and 0.28 logMAR, respectively) in the early AMD group than in the control group. Under mesopic conditions, the mean difference between LC-VA and HC-VA was significantly greater in the early AMD (0.45 logMAR) than the control group (0.27 logMAR). Mean differences between mesopic versus photopic HC-VA and mesopic versus photopic LC-VA were significantly greater in the early AMD than the control group (0.13 and 0.32 logMAR of difference between the means, respectively). Sensitivity and specificity were significantly greater for mesopic LC-VA than for mesopic HC-VA (Receiver Operating Characteristics, area under the curve [AUC], 0.94 ± 0.030 and 0.76 ± 0.067, respectively). AUC values for photopic HC-VA and LC-VA were below 0.70. Conclusions.: Visual acuity testing under low luminance conditions emerged as an optimal quantitative measure of retinal function in early AMD.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 Efecto de un filtro amarillo sobre la función visual mesópica de sujetos emétropes y sujetos miopes operados de cirugía refractiva lasik(2007) Pérez Carrasco, María Jesús; Puell Marín, María CintaOBJETIVO: Analizar la influencia de un filtro amarillo con tratamiento antirreflejante sobre la función visual mesópica de sujetos emétropes y sujetos miopes operados de cirugía refractiva LASIK. MÉTODO: En la 1 etapa de la investigación, se estudió 1 muestra homogénea compuesta por 38 emétropes adultos, a los que se midió la sensibilidad al contraste (SC) (Vistech VCTS 6500), agudeza visual (AV) de bajo contraste (Microlens UPT-1000) y sensibilidad luminosa diferencial (SLD) (Octopus 1-2-3) en el campo visual central (30) sin/con la interposición de un filtro amarillo (X-482) con tratamiento antirreflejante en condiciones mesópicas. En la 2 etapa de la investigación, se valoró la SC sin/con deslumbramiento en una muestra homogénea de 27 miopes intervenidos de cirugía LASIK con un post-operatorio superior al año, y en 30 sujetos control. Las medidas se realizaron sin y con el filtro amarillo (X-482) utilizando el Mesotest II en condiciones mesópicas, y el CGT-1000 en condiciones fotópicas. RESULTADOS: Los emétropes con el filtro amarillo tuvieron un aumento de la SC mesópica para las frecuencias espaciales de 1.5 c/g (p= 0.002) y 6 c/g (p= 0.02), una mejora de la AV del 5% de contraste (p= 0.0004), y un incremento de la SLD para las áreas establecidas del campo visual central (30) (p< 0.05). En condiciones mesópicas, los sujetos LASIK presentaron un descenso de 0.14 unidades logarítmicas en la SC sin deslumbramiento. Con el filtro amarillo, esta variable aumentó significativamente (p= 0.023). Con deslumbramiento, el filtro amarillo también incrementó la SC en el grupo LASIK pero no significativamente. En condiciones fotópicas, no se observaron diferencias significativas. CONCLUSIONES: El uso de los filtros amarillos con tratamiento antirreflejante aumenta la calidad de la función visual de sujetos emétropes en el rango mesópico de iluminación y mejora la SC mesópica de sujetos miopes operados de cirugía refractiva LASIK.Item Effects of Light‐emitting Diode Radiations on Human Retinal Pigment Epithelial Cells in vitro(Photochemistry and Photobiology, 2012) Chamorro, Eva; Muñoz de Luna, Javier; Bonnin Arias, Cristina Natalia; Pérez Carrasco, María Jesús; Vázquez Molini, Daniel; Sánchez Ramos, CeliaHuman visual system is exposed to high levels of natural and artificial lights of different spectra and intensities along lifetime. Light-emitting diodes (LEDs) are the basic lighting components in screens of PCs, phones and TV sets; hence it is so important to know the implications of LED radiations on the human visual system. The aim of this study was to investigate the effect of LEDs radiations on human retinal pigment epithelial cells (HRPEpiC). They were exposed to three light-darkness (12 h/12 h) cycles, using blue-468 nm, green-525 nm, red-616 nm and white light. Cellular viability of HRPEpiC was evaluated by labeling all nuclei with DAPI; Production of reactive oxygen species (ROS) was determined by H2DCFDA staining; mitochondrial membrane potential was quantified by TMRM staining; DNA damage was determined by H2AX histone activation, and apoptosis was evaluated by caspases-3,-7 activation. It is shown that LED radiations decrease 75-99% cellular viability, and increase 66-89% cellular apoptosis. They also increase ROS production and DNA damage. Fluorescence intensity of apoptosis was 3.7% in nonirradiated cells and 88.8%, 86.1%, 83.9% and 65.5% in cells exposed to white, blue, green or red light, respectively. This study indicates three light-darkness (12 h/12 h) cycles of exposure to LED lighting affect in vitro HRPEpiC.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.