Quantifizierung und Progredienz des Gesichtsfeldschadens bei Glaukom ohne Hochdruck, Glaucoma simplex und Pigmentglaukom*

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Abstract
Visual field defects of stages I-IV, in 451 eyes of 451 glaucoma patients were examined with the Octopus 201 perimeter: 83 patients with low-tension glaucoma (LTG), 316 patients with primary open-angle glaucoma (POAG), and 52 patients with pigmentary glaucoma (PG). Program 31 or 33 was used, with an eccentricity range of up to 30.degree., 73 test points, and a 6.degree. grid. The mean total field loss (TL) as well as the mean loss per test point (TL/TP) in the 30.degree. field, in the field 0-10.degree., and 20-30.degree. were calculated for each patient with Programm Delta. In addition, for each visual field the quotient of total loss and of the number of disturbed test points was calculated, providing a measurement of the mean depth of the field defects. For definition and comparison of visual fields in the different glaucomas at identical stages of the disease according to the amount of TL, the 3 patient groups were subdivided into 4 stages of sensitivity loss: Stage 1: TL .ltoreq. 100 dB; Stage 2: TL 101-400 dB; Stage 3: TL 401-800 Stage 4: 801-1600 dB. The results of a comparison of eyes with LTG, POAG, and PG at the same stage of disease were as follows: I. Location of scotomas: 1. Defects more frequent in the lower field in LTG as compared to POAG in stage 2. 2. Defects more frequent in the upper than in the lower field in POAG. 3. Almost equal number of defects in the upper and lower halves in PG. 4. In all 3 glaucoma types the defects are more frequent found in the nasal than in the temporal half of the visual field. 5. In LTG and POAG of all stages the defects are most frequently found in the upper nasal and most seldom in the lower temporal quadrant. 6. In all glaucoma types the defects occur on average most frequently between 10.degree. and 20.degree. of eccentricity. 7. With increasing IOP in POAG the scotomas tend to be equally distributed in the upper and lower quadrants. II. Depth of scotomas: 1. Scotomas are deepest in LTG; they are less deep in POAG, and least deep in PG. 2. In PG the mean scotoma depth depends significantly on maximum IOP. 3. In POAG the mean scotoma depth is independent of maximum IOP; therefore, damaging factors other than pressure-related ones must also be involved in the development of visual field defects in POAG. III. Progression of field loss: Mean visual fields with increasing field loss are calculated from a great number of single fields with almost the same amount of total loss. These mean fields allow conclusions to be drawn regarding the progression of glaucomatous field damage in the three types of glaucoma. Comparing the 4 stages defined according to total loss, a different development of field damage in LTG, POAG, and PG becomes evident: 1. In POAG and PG field defects initially increase mainly in area. Only later, at the advanced stages, does the increase in scotoma depth become more significant. 2. In LTG scotomas are deep from the very beginning. The increase, the depth and area of the defects remain in a constant proportion to one another throughout the subsequent course. The increase in area, however, is predominant.