Abstract
Purpose: :
To describe the differences between fundus autofluoresence (FAF) images in eyes imaged with a confocal scanning laser ophthalmoscope and a digital fundus camera with autofluorescent filters.
Methods: :
Thirty eyes of 15 patients were imaged using the HRA2 (Heidelberg Engineering Heidelberg Germany,) and a Topcon 50 IX fundus camera equipped with autofluorescent filters (580nm excitation and 695 nm barrier filters), digital camera (Kodak Megaplus 1.4i) and ImageNet software (Topcon USA, Paramus N.J.). Images of the 15 patients were obtained using the HRA2 30 degree field . Fifteen autofluorescent images were taken and a mean image was computed using the Heidelberg Version 1.4.1.0 software. Two autofluorescen fundus camera images were taken using a 50–degree field. The images taken on both systems were centered and focused on the macula.
All the images were evaluated by the authors for differences in hypofluorescent and hyerfluorescent areas and autofluorescence patterns.
Results: :
When the images between the two systems were compared, the relative size and extent of hypofluorescent and hyperfluorescent areas were similar. The HRA 2 images showed higher contrast than the fundus camera images. The contrast in the fundus camera images was slightly enhanced to compensate for this difference. Because of the 50 degree field used on the fundus camera, a greater area of the fundus was available for evaluation.
Conclusions: :
Clinically useful autofluorescence imaging can be performed with either the confocal scanning laser ophthalmoscope or a modified digital fundus camera. The SLO generates images with higher contrast but wider field size is available from the fundus camera system. Autofluorescence imaging may play an important role in the evaluation of retinal pathology in both investigational as well as clinical practice settings.
Keywords: imaging/image analysis: clinical • retinal pigment epithelium • macula/fovea