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
5 results
Search Results
Now showing 1 - 5 of 5
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 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 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 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).