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Evaluation of tritan defects is potentially useful for early diagnosis and evaluation of treatment of glaucoma, but the clinical utility of tests such as the Farnsworth-Munsell 100 hue has been limited due in part to effects of individual variations in pupil size and extent of lens yellowing. S-cone contrast sensitivity has been proposed as a more useful tritan test, but it is not known precisely how S-cone contrast sensitivity measured with a computer monitor is influenced by variations in mean S-cone quantal catch due to individual differences in pupil size and lens density. We measured S-cone contrast sensitivity of patients with glaucoma, using 1.0 cycle/degree blue grating superimposed on a bright yellow background. Sensitivity was measured at a range of mean luminances, and pupil size was monitored with a closed-circuit video system. Inter-subject variability was reduced by plotting S-cone contrast sensitivity vs. retinal illuminance rather than stimulus luminance, indicating that much of the variability was due to differences in pupil size. Each patient’s data were fit with a threshold versus retinal illuminance (TVR) function. The TVR analysis suggested that additional variability was due to prereceptoral filters. These results indicate that reductions in S-cone contrast sensitivity at luminances available from computer monitors may reflect, in part, effects of pupillary miosis or lens yellowing, rather than optic nerve damage.

Argon laser tarabeculoplasty (ALT) was performed on 232 eyes of 168 patients. Indication for treatment was progression of visual field loss due to glaucoma, despite maximum tolerated medical treatment. Mean percentage IOP change was -21.6% (± 19); mean F.U. was 9 months (3–21). Visual field were obtained with an Octopus computerized perimeter, using programs 31 or 32. Quantitative analysis of functional results was done only on eyes without significant amount of false answers or visual acuity changes or pupil size changes. 113 eyes met these requirements. IOP variations secondary to ALT were similar to those observed in the total group of treated eyes. Mean F.U. was 10 months (4–21). A visual field change was considered significant when a 15% variation of the mean quadrantic sensitivity was observed and the initial mean sensitivity was greater than 10 dB. When initial mean sensitivity was less than lOdB a 40% change was required to be considered significant. In our sample visual fields improved in 17% of patients, remained unchanged in 55% and worsened in 28%. Although visual field changes and IOP changes did not overlap always as expected there is a good correspondence between hydro dynamic and functional success. Patients with less advanced disease were more likely to have good functional results. The last decades have witnessed much debate regarding how, when, and, even, whether elevated intraocular pressure is responsible for glaucomatous optic nerve damage. Traditionally, treatment has largely been based on lowering intraocular pressure to a level which will no longer compromise an eye. Since the report of Wise and Witter argon laser trabeculoplasty (ALT) has been used successfully to decrease intraocular pressure in patient affected by primary open angle glaucoma (POAG) (7–10). The long-term effect of ALT on the natural history of glaucomatous disease, that is, on the functional visual ability of patients with POAG is, however, not established. We report here information regarding the course of visual field changes in patients undergoing ALT. The data are analyzed to determine possible relationships between change in IOP and change in the visual field.

Argon laser trabeculoplasty (ALT) was performed in 232 eyes of 180 patients affected by uncontrolled primary open angle glaucoma (POAG), exfoliation syndrome glaucoma (ESG) or pigment dispersion syndrome glaucoma (PDSG). Mean follow-up was 9 months (3, 22). Mean IOP change was — 21.6% (± 19) from the initial value. The effect on IOP was larger in patients with ESG, PDSG, and in POAG cases with more pigmented trabecular meshwork. No relationship was found between IOP changes and age of patients. An Octopus,computerized perimeter was used for pre- and post-treatment visual field tests. In 113 eyes Octopus exams met the requirements for quantitative analysis. In this group 17% of visual fields improved, 55% remained stable and 28% worsened. A good functional response was more frequent among the eyes with less advanced disease.