Abstract
Background Lowering intraocular pressure (IOP) is a mainstay of glaucoma therapy. It is, however,
still an open question whether a comparable level of long-term IOP lowering achieved
by different medications results in comparable protection for the retinal ganglion
cells. The purpose of this study was to retrospectively analyze glaucoma damage progression
in two cohorts
of primary open-angle glaucoma patients with different and unchanged therapy over
a period of 3 years, and the main objective of this study was to determine possible
differences in terms of
structural [retinal nerve fiber layer thickness (RNFL)] and functional [visual field
(VF)] outcome.
Patients and Methods The retrospective observational cohort analysis compared two differently treated
groups of glaucoma patients with their original, at study entry, topical therapy
unchanged over 3 years. The main endpoint was the time course of RNFL thickness and
VF mean defect (MD).
Results Twenty-one eyes were included in each group. The first group (21 eyes) was on a fixed
combination of timolol and dorzolamide twice a day and the second group on one drop
of
prostaglandin analog, either latanoprost alone (15 eyes) or travoprost alone (6 eyes),
in an unchanged regimen over a period of 3 years. IOP in mmHg at baseline and at 36
months was
11.9 ± 2.4 and 13.0 ± 2.1 in the first, and 12.9 ± 3.0 and 14.1 ± 3.2 in the second
group, respectively. RNFL thickness values in micrometers were at baseline and at
36 months 77.8 ± 12.3
and 76.6 ± 15.2 in the first, and 77.5 ± 15.2 and 72.8 ± 14.5 in the second group,
respectively. VF MD in dB were 1.7 ± 2.5 and 1.2 ± 2.9 in the first, and 0.9 ± 2.3
and 0.7 ± 2.6 in the
second group, respectively.
Conclusion Both groups had comparable baseline, as well as mean overall IOP. However, the course
of IOP levels over time was different in the two groups, showing earlier and more
pronounced long-term drift in the prostaglandin analog-treated group. RNFL thickness
was comparable at baseline, however, RNFL thinning over time was more pronounced in
the prostaglandin
analog-treated group. There were no statistical differences between the groups in
terms of VF MD at baseline and over time.
Zusammenfassung
Bei der Therapie von Glaukompatienten stellt sich immer noch die Frage, ob ein vergleichbares
Niveau der langfristigen IOD-Senkung durch verschiedene Medikamente zu einem vergleichbaren
Schutz der retinalen Ganglienzellen führt. Wir verglichen in dieser retrospektiven
Analyse zwei Kohorten von Patienten mit primärem Offenwinkelglaukom mit unterschiedlicher
und unveränderter
medikamentösen Therapie über einen Zeitraum von drei Jahren. Bei vergleichbarem mittleren
Gesamtdruck zeigte sich zwar kein signifikant unterschiedlicher Verlauf des Gesichtsfeldes,
jedoch
ein signifikant unterschiedlicher Verlauf der Retinalen Nervenfaserschichtdicke.
Key words glaucoma - POAG - intraocular pressure - retinal nerve fiber layer thickness
Schlüsselwörter Glaukom - POWG - Augeninnendruck - retinale Nervenfaserschichtdicke
