EYE SURGERY, DRAWING. EYE SURGERY, DRAWING Treatment of presbyopia by scleral expansion refractive surgery : scleral incisions. Technics of scleral expansion relies on the controversial theory that the loss of accomodation of presbyopia is not linked to the loss elasticity of the eye lens, but to the lack of space. In fact, the diameter of the eye lens increases naturally with years, so that they would not be enough space to curve and accommodate theory of Schachar, 1995. Enlarge the diameter of