Short wavelength fundus autofluorescence versus near-infrared fundus autofluorescence, with microperimetric correspondence, in patients with geographic atrophy due to age-related macular degeneration
- Elisabetta Pilotto1,
- Stela Vujosevic2,
- Riccardo Melis1,
- Enrica Convento1,
- Patrik Sportiello1,
- Ernesto Alemany-Rubio1,3,
- Sara Segalina1,
- Edoardo Midena1,2
- 1Department of Ophthalmology, University of Padua, Padua, Italy
- 2Fondazione GB Bietti per l'Oftalmologia, IRCCS, Rome, Italy
- 3The Cuban Eye Institute ‘Ramon Pando Ferrer,’ Havana, Cuba
- Correspondence to Dr Elisabetta Pilotto, Department of Ophthalmology, University of Padua, via Giustiniani 2, Padua 35128, Italy;
- Accepted 8 September 2010
- Published Online First 24 October 2010
Aim To compare standard short-wavelength fundus autofluorescence (SW-FAF) and near infrared-wavelength fundus autofluorescence (NIR-FAF) in detecting geographic atrophy (GA) secondary to age-related macular degeneration, and its retinal sensitivity impairment.
Methods Twenty-five consecutive patients (36 eyes) affected by GA were studied by means of fundus autofluorescence imaging, using both SW-FAF (excitation: 488 nm, emission >500 nm) and NIR-FAF (excitation: 787 nm, emission >800 nm). All patients underwent microperimetry to assess fixation characteristics and retinal sensitivity.
Results In the extrafoveal region, the total hypoautofluorescent (hypo-FAF) area was significantly wider with NIR-FAF than with SW-FAF (8.03±6.68 mm2 vs 7.37±6.34 mm2 respectively; p=0.005). In the foveal area, the total hypo-FAF area was smaller with NIR-FAF than with SW-FAF (0.19±0.03 mm2 versus 0.42±0.12 mm2 respectively; p=0.008). Foveal sparing was larger at NIR-FAF compared with SW-FAF (p=0.021). In nine cases (25%) the site of fixation was hypoautofluorescent on SW-FAF, but normal on NIR-FAF with preserved retinal sensitivity.
Conclusions Standard SW-FAF may overestimate GA in the foveal area, correctly detected by NIR-FAF. In the extrafoveal area, SW-FAF may underestimate GA. Standard SW-FAF should be integrated with NIR FAF when detecting and following GA to avoid inconsistent results and misinterpretation, from both a morphological and functional perspective. Microperimetry helps to quantify retinal sensitivity in GA.
- Geographic atrophy
- age-related macular degeneration
- fundus autofluorescence
- diagnostic tests/investigation
Competing interests None.
Patient consent Obtained.
Ethics approval Ethics approval was provided by the Local Ethics Committee of the University of Padua.
Provenance and peer review Not commissioned; externally peer reviewed.