Fundus autofluorescence in patients with leber congenital amaurosis.
OBJECTIVE
Fundus autofluorescence (FAF), as an index of lipofuscin accumulation in the retinal pigment epithelium (RPE), provides indirect information on the level of metabolic activity of the RPE and thus the integrity of the RPE/photoreceptor complex. To investigate whether the photoreceptor/RPE complex is still viable in patients with Leber congenital amaurosis (LCA), FAF imaging was performed.


METHODS
Three patients with LCA (patients A, B, and C; ages, 24, 15, and 37 years, respectively) were enrolled and one patient with RP with preserved visual acuity (age, 28 years) was included as a control. The diagnosis was based on history, visual function, and Ganzfeld electroretinography (International Society for Clinical Electrophysiology of Vision [ISCEV] standard). FAF was recorded with a confocal scanning laser ophthalmoscope (cSLO; Heidelberg Retina Angiograph; Heidelberg Engineering, Heidelberg, Germany).


RESULTS
All patients with LCA had vision reduced to perception of light and had undetectable ERGs. FAF was normal in patient A. In patient B, there was a parafoveal ring of mildly increased FAF. The midperiphery showed mildly decreased FAF. Patient C showed a parafoveal ring of moderately increased FAF. FAF was moderately decreased along the arcades and the midperiphery. The patient with RP showed a parafoveal ring of moderately increased FAF and severely decreased FAF eccentric to the macula including the periphery.


CONCLUSIONS
The FAF findings in these patients with LCA suggest that there is continuous metabolic demand from the photoreceptors and that the RPE/photoreceptor complex is, at least in part, anatomically intact, but the photoreceptors have lost function. These findings may have implications for future treatment. It is notable that more than 20 years of severe visual impairment associated with LCA can be associated with normal FAF, indicating that photoreceptor function may be rescuable.
Institute of Ophthalmology and Moorfields Eye Hospital, London, United Kingdom. hendrickscholl@hotmail.com
Hendrik P N
HP
Scholl
N H Victor
NH
Chong
Anthony G
AG
Robson
Graham E
GE
Holder
Anthony T
AT
Moore
Alan C
AC
Bird
D000293:Adolescent; D000328:Adult; D001766:Blindness / Q000151:congenital / Q000503:physiopathology*; D004596:Electroretinography; D005260:Female; D005453:Fluorescence; D005654:Fundus Oculi; D006801:Humans; D008062:Lipofuscin / Q000378:metabolism; D009887:Ophthalmoscopy; D020419:Photoreceptor Cells, Vertebrate / Q000502:physiology; D010857:Pigment Epithelium of Eye / Q000502:physiology*; D012162:Retinal Degeneration / Q000151:congenital / Q000503:physiopathology*
D008062:Lipofuscin