A model for simulating the endothelial damage caused by surgery is described. The model consists of the introduction of a specially constructed instrument into the anterior chamber and using it for scraping the endothelium of a predetermined, precisely quantifiable area of cornea. The process of healing of the scraped cornea can be followed and measured accurately by biomicroscopy, specular microscopy and histo logical techniques. The model can be used to study the qualitative and quantitative aspects of endothelium healing and the effects of the various endogenous, exogenous and iatrogenic factors on this process. The preliminary data presented shows that the healed endothelium consists of larger and less densly packed cells. The cell density is reduced by 43.3% after one scraping of 57% of the endothelium and by 69.2% after two such operations. Prolonged mild traumatic iritis causes the appearance of endothelial cells with incongruous shapes.