PURPOSE: Age-related macular degeneration (AMD) is a complex, progressive ocular disorder that results in outer retinal ischemia and severe vision loss. Dry AMD, the most common form of AMD, is characterized by the build-up of extracellular drusen deposits, dysfunction of the outer retinal layers and degeneration of photoreceptors. This study aimed to examine the anatomic and physiologic effects of short-term normobaric hyperoxia in patients at different stages of dry AMD. METHODS: Twenty-two eyes from 16 patients diagnosed with dry AMD (11 females, 5 males) were used in this study. Eyes were categorized as having either small drusen or drusenoid pigment epithelial detachments (DPEDs) through optical coherence tomography (OCT) imaging. Eyes associated with small drusen received 3-hours of 40% fraction of inspired oxygen (FiO2) normobaric hyperoxia (NBH), whereas eyes associated with DPEDs received either 3-hour NBH or 3-hours of 20% FiO2 normobaric normoxia (NBN). Visual acuity and OCT images of the macula were taken before and after oxygen treatment. Anatomic outcomes consisted of foveal thickness, foveal volume, macular volume and maximum drusen height; visual acuity was the functional outcome. The relationship between maximum drusen height and visual acuity was then examined to determine if these outcomes were associated. RESULTS: Eyes associated with DPED treated with 3-hour NBH had the largest decreases in foveal thickness, foveal volume, macular volume and maximum drusen height. The macular layers were then divided into inner and outer layers. The outer layers, comprised of Bruch’s membrane, drusen and the retinal pigment epithelium, had significant decreases in anatomic outcomes, whereas the inner layers showed no changes. DPED patients treated with 3-hour NBH also had the largest increase in visual acuity following treatment. There was a significant negative correlation between baseline drusen height and baseline visual acuity. For patients with small drusen treated with 3-hour NBH, there were no significant changes to anatomic or functional outcomes. CONCLUSION: The current study demonstrates the efficacy of short-term administration of normobaric hyperoxia in high-risk dry AMD patients with associated DPEDs. Normobaric hyperoxia appears to be a novel and promising treatment that requires further investigation.

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La présence d'un scotome maculaire oblige les patients à utiliser la vision excentrée ce qui provoque une difficulté à coordonner les systèmes oculomoteur et visuo-attentionnel. La lecture devient alors une des plaintes majeures chez ces patients, et les processus impliqués dans la baisse des performances de lecture restent mal connus. Dans la plupart des cas, le patient développe une ou plusieurs zones de la rétine excentrée dites préférentielles, et dénommées couramment PRLs. Nous nous proposons ici d'utiliser une approche psychophysique afin d'étudier les processus de la lecture en vision excentrée. Nous avons tout d'abord élaboré un test de lecture francophone informatisé suivant les principes des MNRead Acuity Charts afin de pouvoir évaluer la vitesse maximale de lecture chez des patients porteurs de scotomes centraux binoculaires dont l'atteinte avait été mesurée à l'aide d'un micropérimètre MP-1. Deux analyses utilisant des modèles statistiques à effets mixtes nous ont permis de mettre en évidence des prédicteurs efficaces de la vitesse maximale de lecture: 1) l'espace interligne; 2) le type de DMLA ; 3) la surface du scot; 4) la distance entre la PRL de fixation et la fovéa; 5) le statut du cristallin. Puis, nous nous sommes intéressés aux stratégies de lecture déployées par les patients. L'analyse de la distribution verticale des fixations enregistrées pendant la lecture nous a permis de mettre en évidence que dans 97% des cas, les patients utilisent une zone préférentielle de la rétine unique dans le plan vertical.Ces résultats présentent des intérêts théoriques et pratiques dans la création de nouveaux supports visuels et techniques de réadaptation. / Patients with central field loss (CFL) have to use eccentric vision and complain particularly about reading. The purpose of this thesis is to investigate reading processes in those patients using psychophysical tools. First, we investigated predictors of reading performances. We developed a French computerized version of the MNRead Acuity Charts to assess Maximum Reading Speed in patients with binocular scotomas, measured with the microperimeter MP-1. Two distinct analyses using mixed effects models allowed us to estimate the influence of predictors of Maximum Reading Speed: 1) interline spacing; 2) AMD type; 3) scotoma size; 4) distance between fixation PRL and fovea; 5) lens status. Then, we investigated oculomotor patterns of patients during sentence reading. Analysing the vertical distribution of fixations lead us to the conclusion that in most cases (97%), patients use a single eccentric preferred retinal locus (PRL) in the vertical meridian during reading. One potential goal of these studies is to find some ways to enhance text display and improve visual readaptation.