[Why is the Schiötz tonometer not suitable for measuring intraocular pressure? (author's transl)].

The log delta P/delta V-relation curve, as established in human eyes in vivo by new clinical procedure, is shallower than when measured on enucleated eyes and, at least in a number of eyes, not linear. Thus the bases of Friedewald's nomogram are no longer valid and, consequently, the Schiötz tonometer--and all other tonometers inducing volume displacements of more tha 1 microliter--are useless.