The use of the G1 and Octosmart programs in detecting temporal changes in the visual field

Purpose: The Octopus program Octosmart is able to classify visual fields in to six classes. In the program a horizontal bar indicates these classes, an d an indicator points to the most probable position, related to the measure d pathology. The width of this dashed indicator shows the range of possible fluctuations in the measurement and, therefore, its precision. This study sets out to analyse the suitability of this display mode using other visual -field index data. Methods: The visual fields of 83 glaucomatous eyes of 61 patients of various etiological groups and glaucoma suspects were studied for periods varying from 1 to 5 years in a retrospective study. All examina tions were performed with the G1 Octopus program and analyzed with the Octo smart program. The statistical significance of linear trends of the visual- field indices, mean defect (MD) and corrected loss variance (CLV), and the class shown by the indicator (POI = position of indicator) were determined, and their regression coefficients were analyzed by means of a linear trend test as a function of time. Results: Of the sample of 83 tested eyes, a to tal of 18 significant trends were recorded after five examinations. All vis ual-field indices showed a trend towards amelioration. Conclusions: The 18 significant trends observed must be attributed to perturbing longterm fluct uations and, despite their statistical significance, are of little clinical value. It is questionable whether an increased number of examinations per eye would have attenuated the threshold fluctuations sufficiently to make t he change in field class more reliable.