CORNEAL DIAMETER AND PUPIL DIAMETER   
         MEASUREMENT


The corneal and pupil diameters can 
be measured using a mm rule.  The 
pupil diameter is usually measured 
in average room illumination.

More accurate measurements can be 
made using a reticule in the eyepiece 
of the biomicroscope or by using a 
known slit or aperture size on the 
biomicroscope (using the scale on 
the instrument which indicates the 
size).  Other techniques for more 
accurately measuring these 
dimensions can be used but are 
not generally necessary in clinical 
practice.