Placido disk technology allows for the advanced analysis of the tear film, such as NIBUT (Non Invasive Break-up Time). Based on the Ocular Surface Disease Index questionnaire (OSDI), limibal and conjunctival hyperaemia, Meibomian glands analysis, tear meniscus analysis and tear osmolarity, calculated merging together all partial scores, provides an owerall evaluation of the clinical condition of the patient for a comprehensive diagnosis of the dry eye disease.