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Most studies on people with age-related macular degeneration (AMD) have been focused on investigations of low-level processes with simple stimuli like gratings, letters, and in perception of isolated faces or objects. We investigated the ability of people with low vision to analyze more complex stimuli like photographs of natural scenes. Fifteen participants with AMD and low vision (acuity on the better eye <20/200) and 11 normally sighted age-matched controls took part in the study. They were presented with photographs of either colored or achromatic gray level scenes in one condition and with photographs of natural scenes versus isolated objects extracted from these scenes in another condition. The photographs were centrally displayed for 300 ms. In both conditions, observers were instructed to press a key when they saw a predefined target (a face or an animal). The target was present in half of the trials. Color facilitated performance in people with low vision, while equivalent performance was found for colored and achromatic pictures in normally sighted participants. Isolated objects were categorized more accurately than objects in scenes in people with low vision. No difference was found for normally sighted observers. The results suggest that spatial properties that facilitate image segmentation (e.g., color and reduced crowding) help object perception in people with low vision.

Age-related macular degeneration (AMD) is a major cause of visual impairment in people older than 50 years in Western countries, affecting essential tasks such as reading and face recognition. Here we investigated the mechanisms underlying the deficit in recognition of facial expressions in an AMD population with low vision. Pictures of faces displaying different emotions with the mouth open or closed were centrally displayed for 300 ms. Participants with AMD with low acuity (mean 20/200) and normally sighted age-matched controls performed one of two emotion tasks: detecting whether a face had an expression or not (expressive/non expressive (EXNEX) task) or categorizing the facial emotion as happy, angry, or neutral (categorization of expression (CATEX) task). Previous research has shown that healthy observers are mainly using high spatial frequencies in an EXNEX task while performance at a CATEX task was preferentially based on low spatial frequencies. Due to impaired processing of high spatial frequencies in central vision, we expected and observed that AMD participants failed at deciding whether a face was expressive or not but categorized normally the emotion of the face (e.g., happy, angry, neutral). Moreover, we observed that AMD participants mostly identified emotions using the lower part of the face (mouth). Accuracy did not differ between the two tasks for normally sighted observers. The results indicate that AMD participants are able to identify facial emotion but must base their decision mainly on the low spatial frequencies, as they lack the perception of finer details.

Aim of the Study: To evaluate the status of low-vision rehabilitation carried out by the orthoptists in the North of France. This study was a preliminary step in setting up a network between different vision professionals for the management of age-related macular degeneration (AMD) the North of France., Methods: The ASO (Association Septentrionale d'Ophtalmologie) conducted a survey funded by the URCAM (Union Régionale des Caisses d'Assurance Maladie) with the FAQSV (fond d'aide à la qualité des soins de ville). The survey was based on the analysis of two forms sent to orthoptists of the North region of France., Results: The survey analyzed 46 responses (a representative sample with 69% responses) providing a description of the orthoptists of the North of France: 19% males, 81% females whose mean professional experience was 13.3 years. Thirty-four percent of the orthoptists have had training in low-vision rehabilitation. This training was given during the university courses for 21% of responders and during a postgraduate course for 79%. Of the orthoptists surveyed, 64% worked in a private context, 9% in a public context, and 27% in both public and private contexts. Their main activity was in their own private practice for 60%, in an ophthalmologist's office for 20%, in a public institution for 16%, and a private institution for 4%. The mean number of patients treated was 70 per week per orthoptist, with 21% working mostly with children, 36% working mainly with adults between 16 and 60 years of age, and 7% with the elderly, whereas 36% reported no specificity related to patient age. The mean number of patients dealt with for low vision related to AMD was 4.1 per month per orthoptist. The average number of patients dealt with for low vision with no relation to AMD was 1.5 per month. The prescriber of low-vision rehabilitation was an ophthalmologist for 88.9% of the orthoptists and a general practitioner for 11.1%. Questions addressed to AMD patients: at the beginning of the survey, 83.8% of the patients did not have sufficient visual acuity to be able to read a text of current size (Parinaud 4); 40.4% of the patients required help for everyday life, and 59.6% were autonomous. For 7.1% of the patients, low-vision rehabilitation was carried out less than 1 month after the stabilization of retinal lesions, but in 35.3%, rehabilitation was carried out more than 2 years after lesions were stabilized. The main request of the patients involved improvement of near vision (89.9%)., Conclusion: This survey will be a preliminary step in setting up a regional health network coordinating the ophthalmological and orthoptic management of AMD.