Measurement of Retinal Auto Fluorescence With a Fluorescence Lifetime Imaging Ophthalmoscope

Autofluorescence Imaging, Neuroimaging

Fluorescent lifetime microscopy has emerged as a useful tool to study fluorescent lifetimes in vitro. Fluorescence lifetime represents the average amount of time a fluorophore remains in the excited state following excitation and depends on the fluorophores molecular environment. Fluorescence lifetime ophthalmoscopy (FLIO) is a technique which can quantify fluorescence lifetimes in the human retina in vivo. The purpose of this study is to investigate fluorescence lifetime characteristics in the human retina by using a FLIO. The investigators hypothesize that FLIO will allow to identify areas of retinal metabolic stress such as ischemia by detecting changes in fluorescence lifetimes.

Background Ophthalmic imaging has made considerable progress in the last years. Especially the introduction of optical coherence tomography and the scanning laser ophthalmoscope has helped to understand the structural changes underlying various retinal diseases. However, the appearance of structural changes during retinal disease often represents irreversible functional loss with only limited treatment options. In order to prevent loss of vision, retinal diseases should ideally be diagnosed before structural changes occur. This can be achieved by imaging metabolic changes of the retina as most retinal diseases such as age related macular degeneration or diabetic retinopathy are associated with distinct metabolic changes, mainly related to oxidative stress. Recently, a novel device for imaging fluorescent lifetimes of the retina in vivo, the fluorescent lifetime ophthalmoscope (FLIO), has been developed. This device is able to measure fluorescence lifetimes in the retina on a macroscopic level and may be able to shed new light on metabolic diseases of the retina. Objective To define fluorescence lifetime characteristics in healthy patients and patients with various retinal diseases. Methods The investigators will use a novel device, the fluorescence lifetime ophthalmoscope (FLIO) to investigate fluorescence lifetimes in the human retina.

Switzerland