Chahira Miloudi1, Florence Rossant2, Isabelle Bloch3, Céline Chaumette4, Alexandre Leseigneur4, José-Alain Sahel4, Serge Meimon5, Sarah Mrejen4, Michel Paques4. 1. Quinze-Vingts Hospital Departement Hospitalo-Universitaire SightMaintain, Institut National de la Recherche Medicale (INSERM)-Direction de l'Hospitalisation et de l'Organisation des Soins CIC 1423, Paris, France 2Alten Corporation, Boulogne Billancourt, F. 2. Institut Supérieur d'Electronique de Paris, Paris, France. 3. Institut Mines Telecom, Telecom ParisTech, Centre National de la Recherche Scientifique Laboratoire Traitement et Communication de l'Information, Paris, France. 4. Quinze-Vingts Hospital Departement Hospitalo-Universitaire SightMaintain, Institut National de la Recherche Medicale (INSERM)-Direction de l'Hospitalisation et de l'Organisation des Soins CIC 1423, Paris, France. 5. Office National d'Etudes et de Recherches Aéronautiques, Châtillon, France.
Abstract
PURPOSE: The purpose of this study was to describe a previously unreported manifestation of the optical Stiles-Crawford effect (oSCE) in normal eyes. METHODS: In a cohort of 50 normal subjects, the directional reflectance of cones in the retinal periphery was explored by flood-illuminated adaptive optics (FIAO) and optical coherence tomography (OCT). RESULTS: In 32 eyes (64%), off-axis FIAO images of the retinal periphery (∼15-20° from the fovea) showed variably sized patches of hyporeflective dots (called here negative mosaic) coexisting with hyperreflective (positive) cones. In nine cases, shifting the entry pupil toward the optical axis restored the positive cone mosaic, with a point-by-point correspondence between positive and negative mosaics. Rods remained hyperreflective around negative and positive cones. These changes were paralleled by changes of the OCT reflectance of the cone outer segment tips and, to a lesser extent, of the inner/outer segment limit. CONCLUSIONS: By en face FIAO imaging of the retina, the contrast of cones over rods may be strongly dependent on the entry pupil to such an extent that their reflectance is lower than that of rods. We hypothesized that the negative cone mosaic aspect results from the differential Stiles-Crawford effect of cones and rods. Cone reflectance by en face FIAO parallels the reflectance from the cone outer segment tip line and to a lesser extent of the inner/outer segment limit by OCT. Taking this into account, the oSCE is of importance for the interpretation of high-resolution images of photoreceptors. (ClinicalTrials.gov number, NCT01546181.)
PURPOSE: The purpose of this study was to describe a previously unreported manifestation of the optical Stiles-Crawford effect (oSCE) in normal eyes. METHODS: In a cohort of 50 normal subjects, the directional reflectance of cones in the retinal periphery was explored by flood-illuminated adaptive optics (FIAO) and optical coherence tomography (OCT). RESULTS: In 32 eyes (64%), off-axis FIAO images of the retinal periphery (∼15-20° from the fovea) showed variably sized patches of hyporeflective dots (called here negative mosaic) coexisting with hyperreflective (positive) cones. In nine cases, shifting the entry pupil toward the optical axis restored the positive cone mosaic, with a point-by-point correspondence between positive and negative mosaics. Rods remained hyperreflective around negative and positive cones. These changes were paralleled by changes of the OCT reflectance of the cone outer segment tips and, to a lesser extent, of the inner/outer segment limit. CONCLUSIONS: By en face FIAO imaging of the retina, the contrast of cones over rods may be strongly dependent on the entry pupil to such an extent that their reflectance is lower than that of rods. We hypothesized that the negative cone mosaic aspect results from the differential Stiles-Crawford effect of cones and rods. Cone reflectance by en face FIAO parallels the reflectance from the cone outer segment tip line and to a lesser extent of the inner/outer segment limit by OCT. Taking this into account, the oSCE is of importance for the interpretation of high-resolution images of photoreceptors. (ClinicalTrials.gov number, NCT01546181.)
Authors: Susana Marcos; John S Werner; Stephen A Burns; William H Merigan; Pablo Artal; David A Atchison; Karen M Hampson; Richard Legras; Linda Lundstrom; Geungyoung Yoon; Joseph Carroll; Stacey S Choi; Nathan Doble; Adam M Dubis; Alfredo Dubra; Ann Elsner; Ravi Jonnal; Donald T Miller; Michel Paques; Hannah E Smithson; Laura K Young; Yuhua Zhang; Melanie Campbell; Jennifer Hunter; Andrew Metha; Grazyna Palczewska; Jesse Schallek; Lawrence C Sincich Journal: Vision Res Date: 2017-02-27 Impact factor: 1.886