Abstract
Purpose::
To compare the morphologic effect of pegaptanib (MacugenTM) versus bevacizumab (AvastinTM) treatment in neovascular age-related macular degeneration (AMD) using computer-assisted grading software for enhanced quantitative analysis of optical coherence tomography (OCT) images.
Methods::
The raw exported Stratus OCT scan data of consecutive cases undergoing intravitreal pegaptanib (18 eyes) or bevacizumab (35 eyes) treatment for AMD were retrospectively collected. OCT images were analyzed using custom software (OCTOR) designed to calculate thickness and volume of various spaces after manual grading of retinal and subretinal layers. Thickness and volume values of the retina, subretinal fluid (SRF), subretinal tissue (SRT), and pigment epithelial detachments (PEDs) before, and 3 months after, treatment were calculated and compared between both groups. Additionally, results from manual grading were compared against the corresponding automated Stratus OCT output.
Results::
Foveal central subfield (FCS) retinal volumes decreased from 0.26 mm³ to 0.21 mm³ (19% reduction) in the bevacizumab group and remained unchanged at 0.22 mm³ in the pegaptanib group 3 months after injection. Total retinal volume (subfields 1-9) decreased by 0.89 mm³ in the bevacizumab compared to only 0.07 mm³ in the pegaptanib group. Mean SRF, SRT, and PED volumes decreased by 53%, 35%, and 45%, respectively following bevacizumab. In contrast, following pegaptanib, mean SRF decreased by 47%, mean SRT and PED volume actually increased by 9% and 83% at 3 months. Automated Stratus output measurements showed only a small difference (mean decrease of FCS retinal volume 0.05 mm³ after bevacizumab compared to 0.04 mm³ after pegaptanib) between both treatments in this series due to frequent incorrect retinal boundary detection.
Conclusions::
Short term results suggest that intravitreal bevacizumab is associated with an improved anatomical outcome compared to pegaptanib treatment, particularly in reducing SRT and PEDs. Sub-analysis of OCT data may be useful in studying the differential morphologic effects of various treatments.
Keywords: age-related macular degeneration • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • macula/fovea