Priority of test locations for automated perimetry in glaucoma

Static threshold automated perimetry is a demanding test which can be tiring for some patients. The authors investigate how to optimize early stages of the test which can shorten examination time and improve performance. The effectiveness of measuring every point twice to improve diagnostic precision (proportion of eyes correctly diagnosed as normal or glaucomatous) also was evaluated.

The authors evaluated the relative contributions of individual test locations to the sensitivity and specificity of static threshold perimetry. One hundred visual fields (Octopus Program G1) of 100 patients with open-angle glaucoma and early glaucomatous defects were used to rank the most frequently defective test locations. This sequence was modified so that highly correlated points were not ranked together. The sensitivities and specificities of the defined sequence of test presentations were then measured in a separate database of 70 normal controls and 70 patients with early glaucomatous visual field defects.

Sensitivity and specificity were, respectively, 80% and 80% after 12 locations, 89% and 89% after 26 locations, and 97% and 99% after all 59 test locations. The information obtained with the first phase alone approximates that of both phases.

Staging of locations tested with automated perimetry in glaucoma may be a valuable method to reduce examination time, minimize fatigue effects, and optimize diagnostic information. Retesting every point does not improve diagnostic precision.