Abstract
Purpose:
Lipofuscin-related fundus autofluorescence (FAF) can be elicited by different wavelengths. The most detailed experience is available using 488 nm laser light with the Spectralis HRA imaging system (Heidelberg Engineering, Germany). FAF elicited by longer wavelengths (> 500 nm) should be less affected by macular pigment blocking in the foveal area. The present study was performed to evaluate the difference in FAF elicited by either 486 or 518 nm provided by the novel Spectralis MultiColor system in patients with retinal disorders.
Methods:
Between February 2013 and November 2014 a consecutive series of 657 patients with various retinal disorders were examined clinically and with 2 wavelength fundus autofluorescence (B-FAF, 486 nm; G-FAF, 518 nm; Spectralis MultiColor HRA & OCT, Heidelberg Engineering, Germany)). Imaging was performed in 30 or 50 degree mode. Further retinal imaging techniques (e.g. MultiColor reflectance imaging, near-infrared autofluorescence (NIA), spectral domain OCT (SD-OCT), fluorescein angiography (FAG) were performed with the same system when indicated.
Results:
The series of patients included a variety of retinal disorders (e.g. age-related macular degeneration, inherited retinal dystrophies, toxic or autoimmune retinopathies). Regarding the peripheral and perifoveal FAF in 30 and 50 degree mode, no difference between B-FAF and G-FAF was noted. All lesions with either increased or decreased FAF intensity detected by B-FAF were also observed with G-FAF. In contrast, within the foveal area G-FAF was less affected by blockage from macular pigment with higher FAF intensity in normal eyes and in addition G-FAF revealed foveal lesions that were not detectable by B-FAF.
Conclusions:
In comparison to B-FAF, G-FAF provides the opportunity to observe more details in the foveal area without missing other FAF imaging details. G-FAF therefore appears to be the more preferable wavelength for FAF imaging.