Abstract
Purpose: :
The main cause for visual loss in age-related macular degeneration (AMD) is the development of choroidal neovascularization (CNV), which has been shown to occur in 18% of patients over 5 years. Despite advances in diagnoses and treatment of this disease, the injury is still irreversible as well as the visual acuity improvement is limited in the majority of cases. Early detection is the key to preservation of functional vision. The Amnsler grid is commonly used for monitoring patients at home to try to detect CNV in an eye at risk. However, it previously has been shown to be an unreliable tool for diagnosing central visual field defects in patients with AMD. To establish more accurate techniques of measuring visual function, we propose to compare anatomic findings on fundus photography, Optical Coherence Tomography (OCT) and autofluorescence images with ganglion cells subpopulation tests.
Methods: :
All subjects had early AMD (drusen and pigmentary changes). Patients underwent a comprehensive ophthalmologic examination, including the measurement of best-corrected visual acuity, non contact lens slit-lamp biomicroscopy and fundus photography. Autofluorescence image was performed using a confocal laser scanning system. They also underwent standard OCT. Perimetry tests were performed in the central visual field using Standard Automated Perimetry (SAP), Short Wavelength Automated Perimetry (SWAP), Matrix Frequency Doubling Technology (FDT-matrix) and Preferential Hyperacuity Perimeter (PHP). Correlation was made between photography tests and perimetry tests results.
Results: :
As results we describe forty eight eyes of thirty eight patients with early AMD and the results of their tests. The FDT-matrix results were correlated with the anatomic alterations in autofluorescence. The results of PHP were of weak statistical signification with OCT macular volume and fundus alterations. The FDT, SAP and SWAP results were not significantly correlated with the anatomic alterations in fundus photography or OCT.
Conclusions: :
Simple tests can help us to best follow-up the patients with high risk to AMD.Of the four functional tests analysed in this study, FDT-matrix is the only one showing correlation with anatomical findings. Eyecare practitioners can play an important role in preventing vision impairment from AMD and reducing healthcare costs by proactively screening their patients for risk and taking appropriate measures to reduce that risk.
Clinical Trial: :
www.nifesp.br/reitoria/orgaos/comites/etica, CEP 0335/06
Keywords: age-related macular degeneration • drusen • macula/fovea