Abstract
Purpose :
Age-related macular degeneration (AMD) is a leading cause of blindness in the western world. Fluorescence lifetime imaging ophthalmoscopy (FLIO), a novel retinal imaging modality, may be very helpful to identify AMD at early stages.
Methods :
This multi-centered study was conducted in Jena, Germany and Salt Lake City, USA. 134 eyes of 98 patients with AMD (mean age: 73.6 ± 10.3 years) as well as a group of healthy controls were investigated. Using the Heidelberg Engineering FLIO, a 30° retinal field centered at the fovea was investigated. Fluorescence was excited at 473 nm and obtained from a short (SSC, 498-560 nm) and long (LSC, 560-720 nm) spectral channel. The mean fluorescence lifetime (tm) was calculated, obtained from a standardized grid and compared across regions of interest. Optical coherence tomography and fundus photographs were also recorded.
Results :
In eyes with non-exudative AMD, FLIO shows a pattern of prolonged tm in the LSC, which is of ring- or doughnut-like shape. This pattern is usually visible if the pseudo-color range within the software is set from 300 to 500 ps and occurs in early stages of the disease. It is not demarcated by other retinal diseases. In the LSC, tm from the ring was 398 ± 95 ps, while foveal tm was 295 ± 99 ps. The difference between those regions (99 ± 60 ps, p<0.001) is larger than in healthy eyes.
Conclusions :
FLIO detects a clear and typical pattern of prolonged fluorescence signals, which is likely AMD-associated. These changes are visible in early AMD-stages and not masked by the presence of other coexisting retinal diseases. These findings may be useful for early diagnosis and to distinguish AMD from other retinal diseases.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.