[The influence of miosis on the central visual field]

We studied the effects of miosis on mean sensitivity in cases of glaucoma and normal subjects. The visual field in 30 degrees was measured by an automated perimeter Octopus. The subjects consisted of 13 cases (24 eyes) with open angle glaucoma and 10 normal subjects (10 eyes). Glaucomas had a 1.8dB reduction of mean sensitivity with a decrease in pupil size from greater than 3mm to less than 2mm with 3% or 4% pilocarpine, regardless of age and mean sensitivity. Normal subjects showed a depression of 1.6-1.8dB with a decrease in pupil size from more than 3mm to less than 2mm with 3% pilocarpine. There were no significant changes of mean sensitivity in pupil size over 3mm in normal. There was no difference in the reduction of mean sensitivity with miosis between cases of glaucoma and normal subjects. The mean sensitivity measured under conditions of pupil size over 3mm before glaucoma surgery could be quantitatively compared with that of the pupil after operation.