Abstract
Purpose: :
The macular function is generally reduced soon after photodynamic therapy (PDT). The purpose of this study was to evaluate the short-term changes in the focal macular electroretinograms (FMERGs) and macular thickness after PDT combined with intravitreal Bevacizumab for choroidal neovascularization (CNV) associated with age-related macular degeneration.
Methods: :
Five eyes (2 with predominantly classic, 1 with minimally classic, 2 with occult with no classic CNV) were injected intravitreally with 1.25 mg of Bevacizumab one week before PDT. The best-corrected visual acuity (BCVA), FMERGs elicited by a 15° stimulus, and optical coherence tomography (OCT) were performed before and one week after PDT. An increase of >30% in the amplitude of the FMERG was defined as an improvement, and a decrease of >30% was defined as a worsening.
Results: :
The BCVA before intravitreal Bevacizumab ranged from 0.15 to 0.7, and one week after PDT it ranged 0.3 to 1.0. The FMERGs before intravitreal Bevacizumab were markedly reduced in all eyes. The mean amplitudes of the a-wave before and one week after PDT were 0.56 ± 0.11 µV, and 0.53 ± 0.08 µV (mean ± SEM), respectively. The mean amplitudes of the b-wave before and one week after PDT were 1.67 ± 0.28 µV, and 1.45 ± 0.19 µV, respectively. At one week after PDT, the a-waves in 5 eyes were maintained, and the b-waves in 4 eyes were maintained, and was decreased only in one eye. The mean macular thickness within a 3 mm diameter circle centered on the fovea was 335.4 ± 28.6µm before intravitreal Bevacizumab, 315.9 ± 28.6 µm one week after intravitreal Bevacizumab(P>0.05), and 321.0 ± 10.9 µm one week after PDT (P>0.05).
Conclusions: :
The lack of significant changes of in the macular thickness and the FMERGs indicate that macular function and morphology are not altered significantly one week after PDT combined with intravitreal Bevacizumab. These findings suggest that PDT combined with intravitreal Bevacizumab is not as damaging as conventional PDT.
Keywords: age-related macular degeneration • photodynamic therapy • vascular endothelial growth factor