ABSTRACT
This paper introduces a new visual device concept for patients with partially sight loss named Visual Signal Adaptive Restitution (ViSAR). This new concept adapt the signal visual itself to the patient's visual discomfort in real time. While most device tends to compensate for physiology anomaly, ViSAR concept allows to improve the patient-signal interaction and to favor an active vision. This system is the first interacting with eye movements and adapting signal to patient cognitive behavior. Patients do not do anything, ViSAR adapts visual signal to patient's visual discomfort without changing visual and referential reflexes. This new concept involves at the same time engineer, ophthalmologic, optometric and cognitive competencies. ViSAR concept offers a new visual device generation satisfying the growing needs in assistance technology.
ABSTRACT
Confocal scanning laser ophthalmoscope (cSLO) is a new technique which enables ocular fundus image recording and dynamic retinal angiography to be performed. The ocular fundus image is acquired sequentially, point by point, and is reconstructed on a video monitor at the rate of 25 images per second. The aim of this paper is to evaluate the feasibility of measuring retinal arterio-venous filling times (AVFT) with a I + Tech cSLO. Three young adult cynomolgus monkeys and three young adult Göttingen minipigs were used as experimental models. All animals were anesthetized using a zolazepam + tiletamine mixture injected intramuscularly; heart rate and rectal temperature were monitored and corneal irrigation was regularly performed. For all subjects, prior to examination, hematocrit and globe axial length were measured. The images were recorded, stabilized and analyzed. The retinal examination consisted of retinal images with 40 degrees field cSLO, retinal fluorescein angiography and arterio-venous 50% filling time measurements. For each subject all images were easily recorded while keeping the animals in a normally lighted room without having to use any additional optical device. AVFT using an I + Tech cSLO is easily performed in monkeys and minipigs. AVFT measurements in minipigs and monkeys are similar. These results suggest that minipigs can replace monkeys as an experimental species for AVFT investigations.
