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Abstract Background  Autofluorescence (AF) of the retinal pigment epithelium (RPE) are thought to reflect metabolic activity of the RPE cells, which in turn is largely driven by photoreceptor outer segment renewal. In exudative AMD, choroidal new vessels (CNV) may be confined to Bruch’s membrane, or transgress the RPE, with consequence loss of photoreceptor cells. It has been suggested that they may be distinguished with autofluorescence imaging. The aim of our study was to analyze the prognostic value of RPE autofluorescence in relationship to the therapeutic outcome of anti-VEGF (vascular endothelial growth factor) therapy in exudative AMD. Patients and methods  AF images (Heidelberg Retina Angiograph) were obtained from 95 eyes (95 patients, mean age 77.64 years, 39 male and 56 female) with exudative macular lesions and associated drusen before therapy with intravitreal Bevacizumab (Avastin®). Increased, normal, or decreased AF of a central area with diameters of 500 and 1,000 μm around the foveola were distinguished, and compared with the outcome of central vision. As a measure of data reproducibility (inter- and intraobserver variability), the kappa statistics (K > 0.6 “good”, K > 0.8 “excellent”) and exact agreement in % were calculated. Results  Analysis of AF showed a significant difference in outcome of visual acuity in eyes with changes in AF of the central 500 und 1000 μm (Mann-Whitney test, p500 μm p1000 μm = 0.02). Comparison of eyes with increased AF to the other eyes also resulted a significant difference in visual acuity at follow-up (p incr p decr = 0.1733). Conclusions  The RPE-AF of exudative AMD lesions varies greatly. The AF differences probably represent different kinds of metabolism disorders in the RPE. Furthermore, they apparently have a great influence on the chances of anti- vascular endothelial growth factor (VEGF) therapy success; in particular the development of visual acuity is less favorable in eyes with initially increased central AF. [ABSTRACT FROM AUTHOR]

Abstract Background  Complement factor H (CFH) polymorphism Y402H has been shown to be significantly associated with age-related macular degeneration (AMD). Furthermore, histopathological studies in AMD have implicated basal laminar deposits (BLD) in the development of choroidal neovascularization (CNV) membranes. The purpose of this study was to correlate CFH staining in BLD with the CFH genotype at the tyrosine 402 histidine (Y402H) polymorphism. Patients and methods  During macular translocation, 21 angiographically confirmed CNV membranes were extracted in 21 patients. The specimens were analysed histologically for BLD. The presence of CFH, complement proteins, and vitronectin was determined by immunohistochemistry. Finally, the CFH Y402H genotype was established by direct sequencing analysis. Results  Histological examination demonstrated BLD in all of the excised CNV membranes. By immunostaining CFH was detected in the peripheral aspect at the inner and outer surface of BLD, which colocalized with other proteins of the complement cascade (C3, C5b-9). Similarly, vitronectin was detected in all of the BLD investigated. Four patients were noncarriers of CFH Y402H polymorphism, nine patients were heterozygous and eight patients homozygous for the CFH Y402H polymorphism. Conclusions  BLD are composed of different complement factors (factor H, C3, C5b-9) and extracellular matrix proteins such as vitronectin. The prevalence of homozygous carriers in regard to CFH Y402H polymorphism, which is suspicious for AMD, might be associated with increased secretion of vitronectin in response to dysregulation of the complement cascade. [ABSTRACT FROM AUTHOR]