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Limitations and Precautions in the Use of the Farnsworth-Munsell Dichotomous D-15 Test / David A. Atchison in OVS : Optometry & Vision Science, vol. 96, 09 (Septembre 2019)
[article]
in OVS : Optometry & Vision Science > vol. 96, 09 (Septembre 2019)
Titre : Limitations and Precautions in the Use of the Farnsworth-Munsell Dichotomous D-15 Test Type de document : article de périodique Auteurs : David A. Atchison ; Jeffery Hovis ; Stephen Dain Année de publication : 2019 Langues : Français (fre) Descripteurs (mots clés) : [Thésaurus Mesh]Tests de vision
[Thésaurus Mesh]Troubles de la vision
[Thésaurus Mesh]Vision des couleurs
[Thésaurus HELB]:Optique:luminositéRésumé : SIGNIFICANCE: Clinicians who administer the Farnsworth-Munsell D-15 test need to pay attention to the quality and quantity of lighting and the time that they allow for completion of the test, and all repeat attempts need to be included in reports on compliance with color vision standards. PURPOSE: The validity of the Farnsworth-Munsell D-15 has been questioned because practice may allow significantly color vision–deficient subjects to pass. In this article, we review the influence of practice and other factors that may affect the performance. These relate to both the design and the administration of the test. METHODS: We review the literature and present some calculations on limitations in the colorimetric design of the test, quantity and quality of lighting, time taken, and repeat attempts. RESULTS: In addition to the review of the literature, color differences and luminance differences under selected sources are calculated, and the increases in luminance clues under some sources and for protanopes are illustrated. CONCLUSIONS: All these factors affect the outcome of the test and need specification and implementation if the test is to be applied consistently and equitably. We recommend the following: practitioners should never rely on a single color vision test regardless of the color vision standard; lighting should be Tcp 6500 K and Ra > 90; illuminance levels should be between 200 and 300 lux if detection of color vision deficiency is a priority or between 300 and 1000 lux if the need is to test at the level where illuminance has minimal influence on performance; illuminance should be reported; time limits should be set between 1 and 2 minutes; repeat testing (beyond the specified test and one retest) should be carried out only with authorization; and initial and repeated results should be reported. A set of test instructions to assist in the consistent application of the test is provided in the Appendix. Permalink : https://bibliotheque.helb-prigogine.be/opac_css/index.php?lvl=notice_display&id= [article]Exemplaires
Cote Support Localisation Section Disponibilité aucun exemplaire Suprathreshold motion perception in anisometropic amblyopia Interocular speed matching and the pulfrich effect / Goro Maehara in OVS : Optometry & Vision Science, vol. 96, 06 (Juin 2019)
[article]
in OVS : Optometry & Vision Science > vol. 96, 06 (Juin 2019)
Titre : Suprathreshold motion perception in anisometropic amblyopia Interocular speed matching and the pulfrich effect Type de document : article de périodique Auteurs : Goro Maehara ; Syunsuke Araki ; Tsuyoshi Yoneda ; Benjamin Thompson ; Atsushi Miki Année de publication : 2019 Langues : Français (fre) Descripteurs (mots clés) : [Thésaurus Mesh]Amblyopie
[Thésaurus Mesh]Collecte de données
[Thésaurus Mesh]Mouvement
[Thésaurus Mesh]Perception
[Thésaurus HELB]:Optique:luminance
[Thésaurus HELB]:Optique:luminositéRésumé : SIGNIFICANCE Our results indicate that the difference in perceived luminance between the amblyopic and fellow eyes that is present under dichoptic viewing conditions does not affect the perceived speed of suprathreshold motion stimuli. This finding provides a new insight into suprathreshold perception in amblyopia.
PURPOSE Interocular matching experiments indicate that dichoptically presented stimuli have a lower perceived luminance in amblyopic eyes relative to fellow eyes. This may be a consequence of interocular suppression. We investigated whether this effect extends to suprathreshold motion perception.
METHODS Participants with amblyopia and control observers matched the perceived speed of dichoptically presented random-dot kinematograms and the perceived luminance of gray patches. Control participants also performed the speed matching task with a neutral density filter over one eye to simulate a perceived luminance reduction.
RESULTS The amblyopia group exhibited lower perceived luminance in the amblyopic than in the fellow eye, as has previously been reported. However, interocular speed matching was veridical. For control observers, perceived speed was reduced in the eye with a neutral density filter relative to the nonfiltered eye. To assess whether the perceived luminance reduction in the amblyopic eye affected binocular function, we also measured the Pulfrich effect in the amblyopia group with equal luminance presented to each eye. No patients reported a spontaneous Pulfrich effect.
CONCLUSIONS The results suggest that suprathreshold speed perception is intact in the amblyopic eye when both eyes are open.Permalink : https://bibliotheque.helb-prigogine.be/opac_css/index.php?lvl=notice_display&id= [article]Exemplaires
Cote Support Localisation Section Disponibilité aucun exemplaire The Effect of Blue-blocking Lenses on Photostress Recovery Times / Hind Saeed Alzahrani in OVS : Optometry & Vision Science, vol. 97, 11 (Novembre 2020)
[article]
in OVS : Optometry & Vision Science > vol. 97, 11 (Novembre 2020)
Titre : The Effect of Blue-blocking Lenses on Photostress Recovery Times Type de document : article de périodique Auteurs : Hind Saeed Alzahrani ; Sieu Khuu ; Adiba Ali ; Maitreyee Roy Année de publication : 2020 Langues : Français (fre) Descripteurs (mots clés) : [Thésaurus Mesh]Accommodation oculaire
[Thésaurus Mesh]Dispositifs de protection des yeux
[Thésaurus Mesh]Étude comparative
[Thésaurus Mesh]Rétine
[Thésaurus Mesh]Temps
[Thésaurus HELB]:Optique:Lumière bleue / optique
[Thésaurus HELB]:Optique:luminositéRésumé : SIGNIFICANCE: The selective reduction in visible wavelengths transmitted through commercially available blue-blocking lenses (BBLs) is known to influence the appearance and contrast detection of objects, particularly at low light levels. This influence may impair the human retinal receptor response time to dynamic light changes during photostress events. PURPOSE: This study aimed to assess whether BBLs selectively affect photostress recovery times (PSRTs) for chromatic and achromatic stimuli of different Weber contrasts that were viewed on a dark black background. METHODS: Photostress recovery times were measured in 12 younger participants (18 to 39 years old) with no history of ocular disease or abnormal vision. Photostress recovery times were evaluated for four brands of BBLs, which were compared with a control lens. In these experiments, after exposure to an intense light source for 5 seconds, the time taken to recover vision and correctly identify a computer-generated letter stimulus viewed under low and high luminance levels was determined, which means perception is likely to be governed by mesopic and photopic conditions. Across conditions, the letter stimulus was achromatic and chromatic and could differ in luminance contrast. RESULTS: Under photopic stimulus conditions, although reducing luminance contrast increased PSRTs, BBLs had no significant effect on PSRTs relative to control lens. However, under mesopic stimulus conditions, BBLs significantly affect PSRTs for both achromatic (F2.006,8.02 = 61.95, P < .0001) and chromatic stimuli (F3,16 =139.01, P < .0001), particularly for blue targets, which had considerably longer PSRTs (38.40 seconds). The brand of BBL was also shown to selectively affect PSRTs, with those with transmittance profiles that block the most blue light having longer PSRTs. CONCLUSIONS: The present study suggests that, although the color and contrast of the target stimuli affected recovery times, the difference in recovery times between different types of BBLs was noticed only under low-lightlevel stimulus conditions. Permalink : https://bibliotheque.helb-prigogine.be/opac_css/index.php?lvl=notice_display&id= [article]Exemplaires
Cote Support Localisation Section Disponibilité aucun exemplaire The Effect of Retinal Illuminance on the Subjective Amplitude of Accommodation / Francisco Lara in OVS : Optometry & Vision Science, vol. 97, 08 (Aout 2020)
[article]
in OVS : Optometry & Vision Science > vol. 97, 08 (Aout 2020)
Titre : The Effect of Retinal Illuminance on the Subjective Amplitude of Accommodation Type de document : article de périodique Auteurs : Francisco Lara ; Antonio J. Del Águila-Carrasco ; Iván Marín-Franch ; Resurrección Riquelme-Nicolás ; Norberto L López-Gil Année de publication : 2020 Langues : Français (fre) Descripteurs (mots clés) : [Thésaurus Mesh]Accommodation oculaire
[Thésaurus Mesh]Pupille
[Thésaurus HELB]:Optique:amplitude d'accommodation
[Thésaurus HELB]:Optique:luminositéMots-clés : presbytie nocturne Résumé : SIGNIFICANCE: We show that the amplitude of accommodation decreases with retinal illumination even under
photopic reading conditions and a constant pupil size. This result provides a basis for clinical approaches that
are not based on an optical explanation.
PURPOSE: We investigated the effect of retinal illuminance on the amplitude of accommodation while the pupil of
the eye remained constant.
METHODS: The amplitudes of accommodation of 10 young subjects (from 20 to 38 years of age) and that of 10
presbyopic subjects (from 45 to 54 years of age) were measured subjectively through an artificial pupil of 5 mm
using a Badal optometer and for four values of retinal illuminance: 222, 821, 2138, and 5074 trolands. Phenylephrine was instilled to all the subjects to ensure that their natural pupil was greater than the artificial one in all experimental runs. Linear mixed-effects model for repeated measures with age and log luminance as covariates were used
to check whether changes in amplitude of accommodation with retinal illumination were statistically significant.
RESULTS: In the range of illuminances tested, the amplitude of accommodation decreased on average from 6.34
to 4.35 D in the young subjects and from 1.69 to 1.04 D in the presbyopic subjects. Illuminance was associated
with the amplitude of accommodation in both young and presbyopic groups, with P < .01.
CONCLUSIONS: The reduction in the amplitude of accommodation with target illumination (a phenomenon
named night presbyopia) under photopic light conditions is not only due to a reduction in the depth of focus as
a consequence of pupil dilation; it is strongly affected by the decrease of retinal illuminationPermalink : https://bibliotheque.helb-prigogine.be/opac_css/index.php?lvl=notice_display&id= [article]Exemplaires
Cote Support Localisation Section Disponibilité aucun exemplaire