Fig. 16. This examination of a glaucomatous eye with a cataract, employing program 30-2 of the Humphrey Field Analyzer, demonstrates the uses of global indices. The mean deviation (MD) of 16.79 dB represents the significant degree of generalized reduction in threshold sensitivities secondary to the media opacity. The corrected pattern standard deviation (CPSD) of 8.39 reflects the additional localized reduction in sensitivities resulting from the dense superior nasal step, well demonstrated in the pattern deviation display. The pattern deviation display also discloses the abnormal loci in the Bjerrum area in the superotemporal and inferonasal quadrants.