Abstract
Purpose: :
Patients with reticular drusen in non-exudative age related macular disease show a higher risk of disease progression than other modified FAF patterns. Identifying these modified FAF patterns is crucial for detailed disease monitoring and detection of progression. The purpose of this study was to compare a fundus camera system (FC) with confocal scanning laser ophthalmoscope (cSLO) in fundus autofluorescence imaging of non-exudative AMD.
Methods: :
136 eyes of 83 individuals with dry age-related macular degeneration underwent ophthalmological examination, color fundusphotography, FAF and OCT. The devices for FAF were FC VISUCAM® NM/FA opt. FAF (Carl Zeiss Meditec, Germany; Excitation: 510 - 580 nm; Emission: 650 - 735 nm) and cSLO Heidelberg Retina Angiograph (HRA®) (Heidelberg Engineering, Germany; Excitation: 488 nm; Emission: >500 nm). The main points of interest with regards to clinical disease identification were: detection of reticular drusen, overall image quality and area of altered FAF signal. Images were independently graded by 2 experienced observers and agreements were evaluated.
Results: :
14 subjects (10,3%) were identified with reticular drusen with the cSLO and 13 (9,5%) with the fundus camera system (FC). Overall image quality and was semi-quantitatively graded as good in 10 patients with the FC and 11 with the cSLO. In one patient the reticular drusen pattern could not be detected with the FC because of low contrast. The mean area of altered FAF signal was 26,19mm2 (stdev. 6,23) with the cSLO and 23,81 mm2 (stdev. 8,19) with the FC.
Conclusions: :
Both systems showed high consistency concerning medical information and interobserver agreement was high. Concerning overall image quality both systems delivered comparable results. HRA showed better results in identifying smaller changes whereas the FC showed a better overview. There were characteristic differences in signal intensity demonstrating a higher sensitivity of the cSLO detecting RPE alterations. Both systems seem to be suitable for detecting and monitoring of reticular drusen patterns.
Keywords: age-related macular degeneration • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • retinal pigment epithelium