Quantitative studies in stereochronoscopy (Sc): application to the disc in glaucoma

Abstract

In some details our standard procedure of stereochronoscopic disc picture-taking has been improved. For clinical use (demonstration of a change in the disc surface) a semi-quantitative evaluation with a stereoscope is generally sufficient. For a more accurate and quantitative analysis a flicker comparator is used. A graphical or numerical display of the results allows the follow-up of changes at a given location on the disc over any time interval, e.g. several years in glaucoma simplex, if pictures are taken every 2–4 months. Characteristic curve courses result, of which we describe (1) to and fro movement of the position of a given object on the disc, “papillary unrest” (2) progression of parallax, and (3) “events”. The difficulty of judging the efficacy of a therapy is made evident. Here stereochronoscopy should prove to be useful when employed in the form of control charts.