Estudio de la progresión perimétrica en distintos tipos de glaucomasistemas de diagnóstico y factores de riesgo

Abstract

Background: The white on white automated perimetry performed on a Humphrey Visual Field Analyzer is used worldwide for the diagnosis and follow up of the perimetric damage developed during glaucoma. Due to the lack of a gold standard among the strategies developed for the diagnosis of perimetric progression, many procedures have been published. One of the latest is the Visual Field Index (VFI). Open angle glaucomas can be classified depending on the optic nerve head appearance, and correlated to this morfological classification a perimetric and clinical behaviour is expected. Our purpose is to compare the performance of three different types of glaucoma considering the appearance of the optic nerve head, using the VFI software compared with three other progression analysis systems. The validity of the progression analysis systems has been assessed with the analysis of the behaviour of certain clinical features associated with perimetric progression. Material and methods: 296 eyes of 153 open angle glaucoma patients under treatment were recruited for this retrospective study. 112 eyes with focal glaucoma, 136 eyes with high pressure glaucoma and 48 eyes with pseudoexfoliative glaucoma. All the available visual fields of these eyes were analyzed with the GPA II software. The visual fields of those eyes that had perimetric strategies and follow ups consistent with this system were then analyzed with two different types of perimetric progression algorithm: the AGIS Score and clinical criteria. Certain clinical data was collected from the medical history to examine the validity of the progression diagnosis showed by the different algorithms. Conclusions:A new perimetric follow up algorithm, different from the classical recommendations, is necessary in order to be able to use the GPA-II software. There are no statistically significant differences between the prevalence of progression of focal and high pressure glaucomas regardless of the algorithm used, but the prevalence of progression differs depending on which algorithm we use. Of the algorithms of progression studied, the AGIS Score is the most specific one, as its diagnosis of progression has a higher correlation with clinical data related with perimetric progression. The fact that the different types of glaucoma behave differently depending of the progression analysis system used, may indicate that they are different entities within the same disease. The VFI rate of progression per se, without statistical analysis, is a better predictor of progression than the level of statistical significance of the VFI rate obtained by the GPA sofware.