A CLUSTER AND SCOTOMA ANALYSIS BASED ON EMPIRIC CRITERIA

From a collection of 288 visual fields of glaucomatous or glaucoma sus pects, 30 were selected at random and were analyzed by one expert inte rpreter. Visual field damage varied from nonexistent to severe. The in terpreter defined clusters or scotomas subjectively according to adjac ency criteria: adjacent test locations which exceeded a critical loss value were grouped as clusters or scotomas. A computer algorithm has b een devised which simulates such evaluation methods. In general, a sta ndard setting of several parameters produced a cluster display contain ing the same number of clusters as determined by the expert interprete r. Another display mode grouped clusters according to polygonal areas of a predetermined size (Voronoi diagram). Due to the broad selection of visual field defects, the specificity of the program with regard to various field decay patterns was small and it should thus be applicab le to a broad spectrum of glaucomatous field damage.