MEASURING THE SIZE 
                     OF DEFECTS

It is important in following and documenting conditions to accurately measure them.  The biomicroscope can be used in to do this in a couple of ways.  One is to have a reticule with a millimeter scale in the eye piece.  This is an accurate method but has a  problem in that it must be calibrated for each magnification.

Another method is to use the width or height of the light beam or a known spot size.  The beam is set to the width of the defect (scar, abrasion, neovascularization, etc.).