Adding automated perimetry to glaucoma evaluation and treatment

Tangent-screen visual fields were compared with the fields determined by a newly acquired automated perimeter in 100 eyes of consecutive patients with glaucoma or suspected glaucoma. The tangent screen found defects in 12 eyes, and the automated perimeter found defects in 34 eyes. Because the automated perimeter found new defects or defects much worse than were found by the tangent-screen examinations, three patients received timolol, and a laser iridotomy, two laser trabeculoplasties, and three filtering operations were done on other patients. The major benefit in switching from tangent screen to automated perimetry was increased confidence in the visual fields tested as an indicator for treating patients with glaucoma. A minor problem in using the automated perimeter was that the testing was slightly longer and more tiring. This problem was reduced by using a translucent occluder, rather than the universally used opaque one.