Cone abnormalities in fundus albipunctatus associated with RDH5 mutations assessed using adaptive optics scanning laser ophthalmoscopy.
OBJECTIVE
To assess macular photoreceptor abnormalities in eyes with fundus albipunctatus with RDH5 mutation by using adaptive optics scanning laser ophthalmoscopy (AO-SLO).


METHODS
Prospective cross-sectional study.


METHODS
Ten eyes with fundus albipunctatus and 11 normal eyes underwent a full ophthalmologic examination, microperimetry, spectral-domain optical coherence tomography (SD OCT), and imaging with a prototype AO-SLO system. Cone density and spatial organization of the cone mosaic were assessed using AO-SLO images. Statistical analysis was done using data from right eyes of all patients.


RESULTS
Four patients had the same mutation in RDH5 (c.928delC/insGAAG), and 1 patient had a novel mutation in RDH5 (c.718delG). AO-SLO revealed the presence of small patchy dark areas representing cone loss in the macula of all eyes with fundus albipunctatus, including eyes for which fundus photographs showed no macular abnormalities and SD OCT did not reveal any visible defects in the photoreceptor layer. Compared to normal eyes, eyes with fundus albipunctatus demonstrated significantly lower cone density in areas at 0.5 mm from the center of the fovea (P = .020). At 0.5 mm and 1.0 mm from the center of the fovea, eyes with fundus albipunctatus showed fewer cones with 6 neighbors (P = .041 and P = .006). AO-SLO revealed hyperreflective mosaics surrounded by hyporeflective rings in areas corresponding to the retinal flecks.


CONCLUSIONS
Macular cone density is lower and the regularity of the macular cone mosaic spatial arrangement is disrupted in eyes with fundus albipunctatus. AO-SLO imaging is a sensitive quantitative tool for detecting photoreceptor abnormalities in eyes with fundus albipunctatus.
Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Yukiko
Y
Makiyama
Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan. Electronic address: ohoto@kuhp.kyoto-u.ac.jp.
Sotaro
S
Ooto
Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Masanori
M
Hangai
Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Ken
K
Ogino
Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Norimoto
N
Gotoh
Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Akio
A
Oishi
Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Nagahisa
N
Yoshimura
D000293:Adolescent; D000328:Adult; D000429:Alcohol Oxidoreductases / Q000235:genetics*; D003430:Cross-Sectional Studies; D017931:DNA Primers / Q000737:chemistry; D004596:Electroretinography; D005260:Female; D005451:Fluorescein Angiography; D005584:Fovea Centralis; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009887:Ophthalmoscopy; D055095:Optics and Photonics; D016133:Polymerase Chain Reaction; D011446:Prospective Studies; D017949:Retinal Cone Photoreceptor Cells / Q000473:pathology*; D012164:Retinal Diseases / Q000175:diagnosis / Q000235:genetics*; D041623:Tomography, Optical Coherence / Q000379:methods; D014792:Visual Acuity; D058609:Visual Field Tests; D055815:Young Adult
D017931:DNA Primers; D000429:Alcohol Oxidoreductases; C105846:retinol dehydrogenase 5