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Available from: Joseph Carroll, Jan 14, 2014
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    • "However at 2.0 deg from the fovea, cone spacing is increased in the patient (7.42 μm vs. 5.58 μm), indicating lower cone density. In addition, the cones take on a " bubble-wrap " type appearance, which has been described before (Duncan et al. 2007; Godara et al. 2010). The raised appearance results from a non-uniform reflectance across the cone aperture. "
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    ABSTRACT: Recent years have seen an explosion in the development of novel ophthalmic imaging devices, delivering noninvasive views of the living retina. Adaptive optics (AO) imaging systems enable resolution of individual cells in the living retina. Analysis of these images has been limited to measures of cone density and regularity. Here, we introduce a small case series where the information in the high-resolution image extends beyond these standard metrics. These images should serve as the basis for evolving discussion as to how best to interpret AO retinal images.
    Full-text · Article · Jan 2012 · Advances in Experimental Medicine and Biology
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    ABSTRACT: To study cone photoreceptor structure and function associated with mutations in the second intradiscal loop region of peripherin/RDS. High-resolution macular images were obtained with adaptive optics scanning laser ophthalmoscopy and spectral domain optical coherence tomography in four patients with peripherin/RDS mutations and 27 age-similar healthy subjects. Measures of retinal structure and fundus autofluorescence (AF) were correlated with visual function, including best-corrected visual acuity (BCVA), kinetic and static perimetry, fundus-guided microperimetry, full-field electroretinography (ERG), and multifocal ERG. The coding regions of the peripherin/RDS gene were sequenced in each patient. Heterozygous mutations in peripherin/RDS were predicted to affect protein structure in the second intradiscal domain in each patient (Arg172Trp, Gly208Asp, Pro210Arg and Cys213Tyr). BCVA was at least 20/32 in the study eye of each patient. Diffuse cone-greater-than-rod dysfunction was present in patient 1, while rod-greater-than-cone dysfunction was present in patient 4; macular outer retinal dysfunction was present in all patients. Macular AF was heterogeneous, and the photoreceptor-retinal pigment epithelial (RPE) junction layer showed increased reflectivity at the fovea in all patients except patient 1, who showed cone-rod dystrophy. Cone packing was irregular, and cone spacing was significantly increased (z-scores >2) at most locations throughout the central 4° in each patient. peripherin/RDS mutations produced diffuse AF abnormalities, disruption of the photoreceptor/RPE junction, and increased cone spacing, consistent with cone loss in the macula. The abnormalities observed suggest that the integrity of the second intradiscal domain of peripherin/RDS is critical for normal macular cone structure.
    Full-text · Article · Nov 2010 · Investigative ophthalmology & visual science
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    ABSTRACT: OBJECTIVE To study macular structure and function in patients with Usher syndrome type III (USH3) caused by mutations in the Clarin 1 gene (CLRN1). METHODS High-resolution macular images were obtained by adaptive optics scanning laser ophthalmoscopy and spectral domain optical coherence tomography in 3 patients with USH3 and were compared with those of age-similar control subjects. Vision function measures included best-corrected visual acuity, kinetic and static perimetry, and full-field electroretinography. Coding regions of the CLRN1 gene were sequenced. RESULTS CLRN1 mutations were present in all the patients; a 20-year-old man showed compound heterozygous mutations (p.N48K and p.S188X), and 2 unrelated women aged 25 and 32 years had homozygous mutations (p.N48K). Best-corrected visual acuity ranged from 20/16 to 20/40, with scotomas beginning at 3° eccentricity. The inner segment-outer segment junction or the inner segment ellipsoid band was disrupted within 1° to 4° of the fovea, and the foveal inner and outer segment layers were significantly thinner than normal. Cones near the fovea in patients 1 and 2 showed normal spacing, and the preserved region ended abruptly. Retinal pigment epithelial cells were visible in patient 3 where cones were lost. CONCLUSIONS Cones were observed centrally but not in regions with scotomas, and retinal pigment epithelial cells were visible in regions without cones in patients with CLRN1 mutations. High-resolution measures of retinal structure demonstrate patterns of cone loss associated with CLRN1 mutations. CLINICAL RELEVANCE These findings provide insight into the effect of CLRN1 mutations on macular cone structure, which has implications for the development of treatments for USH3. TRIAL REGISTRATION clinicaltrials.gov Identifier:NCT00254605.
    Full-text · Article · Sep 2012 · Archives of ophthalmology
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