Pre- and post-operative results of static perimetry in patients with glaucoma simplex

Abstract

The best results for follow-up were obtained with single stimulus static perimetry. The quality of this type of follow-up examination was good in 60% of cases, adequate in 25% and fair in 15%. The combination of accurate single stimulus static perimetry and expert evaluation of the results was necessary, if the judgement of pseudo-deterioration or improvement was to be avoided. That this is a real danger is apparent from the Tuebingen glaucoma operation study. This was the 1st well-controlled prospective post-operative visual field study. The changes which occurred during a follow-up period of 2 years were, generally speaking, not large. There were no dramatic changes in the extent and intensity of the defects. At the end of the 2-year period continuation of a post-operative deterioration could only be observed in 5 cases. In most cases deterioration took place in the 1st post-operative year, after which the visual field became stable unless the IOP was too high. All the cases of late visual field deterioration could be explained by a rise in IOP. In 4 cases significant improvement occurred. These cases demonstrated that partial reversibility of glaucomatous visual field defects did exist. In the age group under 65 yr a relationship was seen between IOP and visual field. In the age group above 65 years other causes were often responsible for the alterations in the visual field (cataract, point of no return, cardiovascular disease). Visual field changes related to the IOP were mainly to be expected in the early stages of glaucomatous visual field defects. Central rests are little affected by the trauma of an operation within a period of 2 yr. After a operation the visual fields deteriorated less than before the operation or remained stationary.