Illustrations created for Dr. Kanav Khanna (ophthalmologist at the University of Tours) for a doctoral thesis in science focused on the metabo-lipidomic approach applied to tears and the contribution of the ocular surface in the search for biomarkers in amyotrophic lateral sclerosis (Charcot's disease). The main illustration was designed to summarize, in the form of a poster, the four main research steps conducted both before and by his research team.