Impact of intraocular pressure regulation on visual fields in open-angle glaucoma.
OBJECTIVE
To investigate the correlation of different parameters of intraocular pressure (IOP) to visual field decay in open-angle glaucoma.


METHODS
Analysis of visual field decay during a prospective, randomized clinical trial comparing primary laser trabeculoplasty with medication.


METHODS
Of a total of 82 included eyes in 82 patients with newly detected high-pressure open-angle glaucomas, 76 (55 capsular, 21 simple) fulfilled the 2-year follow-up with the stated number of reliable visual field examinations and were included in this analysis.


METHODS
Automated perimetry and a daytime IOP curve were taken every second month during the 2-year follow-up.


METHODS
Six IOP parameters were evaluated and correlated to visual field outcome. The subgroups with the two types of glaucoma (capsular and simple) were analyzed separately.


RESULTS
Visual field decay showed greater correlation to IOP variation (range and peak) and mean IOP than IOP at start or degree of IOP reduction. The relation between mean IOP and visual field decay in the whole group was not quite linear, with more decay at higher IOP levels. The association between IOP regulation and visual field decay was most pronounced in capsular glaucoma, whereas the results in the small group of simple glaucomas were inconclusive.


CONCLUSIONS
Visual field prognosis in high-pressure open-angle glaucoma, essentially capsular glaucoma, is better in patients with smaller IOP variation and poorer in patients with high mean IOP.
D000368:Aged; D000369:Aged, 80 and over; D005500:Follow-Up Studies; D005902:Glaucoma, Open-Angle / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D007429:Intraocular Pressure; D053685:Laser Therapy; D008875:Middle Aged; D010862:Pilocarpine / Q000627:therapeutic use*; D011379:Prognosis; D011446:Prospective Studies; D014130:Trabeculectomy; D058609:Visual Field Tests; D014794:Visual Fields / Q000502:physiology*