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1.
Free Radic Res ; 48(7): 740-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24628396

RESUMO

BACKGROUND: Because patients with cystic fibrosis (CF) are living longer, chronic malabsorption of carotenoids associated with CF resulting in decreased macular pigment (MP) may affect macular long-term health in later-life pathology. This study compared the macular pigment optical density (MPOD) and corresponding central macular volume (MV) of adult CF subjects and age-matched normal controls subjects to determine whether chronic malabsorption associated with CF could adversely affect macular photoreceptor anatomy. OBJECTIVE: Our aim was to compare MPOD with measurements of central MV in CF patients with age-matched controls. Design. In nine adult CF patients (ages: 29-46) without a history of carotenoid supplementation or known retinal or optic nerve disease MPOD and MV were measured by heterochromatic flicker photometry (HFP) and optical coherence tomography (OCT), respectively, and compared to results obtained from 14 age-matched controls. RESULTS: MPOD was significantly reduced at 15' and 30' eccentricities in CF subjects compared to normal subjects (mean difference -0.21 at 15', -0.25 at 30', p < 0.005). No significant difference, in MV noted at any of the eccentricities tested between CF and normal subjects (CF: normal MV ratios ranged from 0.94 to 1.1 for all eccentricities with p > 0.1 at all eccentricities). Best corrected vision acuity and fundus examination were normal in all subjects. CONCLUSIONS: Unsupplemented CF patients have markedly lower levels of macular carotenoids (e.g., lutein and zeaxanthin), but well-maintained visual function and no significant reductions in central MV primarily composed of macular photoreceptors. Future studies are needed to determine whether the lifelong decrease in protective central retinal carotenoids predisposes CF patients to later-life retinal pathology.


Assuntos
Fibrose Cística/complicações , Fibrose Cística/patologia , Macula Lutea/metabolismo , Pigmento Macular/metabolismo , Doenças Retinianas/metabolismo , Doenças Retinianas/patologia , Adulto , Fibrose Cística/metabolismo , Feminino , Humanos , Macula Lutea/patologia , Masculino , Pessoa de Meia-Idade , Doenças Retinianas/complicações
2.
Opt Lett ; 38(22): 4801-4, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24322136

RESUMO

We present a method for optimization of optical coherence tomography images using wavefront sensorless adaptive optics. The method consists of systematic adjustment of the coefficients of a subset of the orthogonal Zernike bases and application of the resulting shapes to a deformable mirror, while optimizing using image sharpness as a merit function. We demonstrate that this technique can compensate for aberrations induced by trial lenses. Measurements of the point spread function before and after compensation demonstrate near diffraction limit imaging.


Assuntos
Artefatos , Aumento da Imagem/instrumentação , Lentes , Tomografia de Coerência Óptica/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Retroalimentação , Transdutores
3.
Eye (Lond) ; 25(6): 775-83, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21436847

RESUMO

PURPOSE: The purpose of this study is to evaluate the macular morphological changes associated with idiopathic epiretinal membrane (iERM) using high-resolution Fourier-domain optical coherence tomography (FD-OCT), as they correlate with visual acuity and microperimetry (MP-1). METHODS: In all, 24 eyes (19 subjects) with iERM were imaged prospectively using FD-OCT with axial resolution of 4.5 µm and transverse resolution of 10 to 15 µm. MP-1 and Stratus OCT were carried out in a subset of eyes. RESULTS: The mean log of the minimum angle of resolution best-corrected visual acuity (BCVA) was 0.18±0.16 (range: -0.08 to 0.48, Snellen equivalent 20/15(-1) to 20/60). ERM was visualized in all 24 eyes with FD-OCT and in 17 eyes (85%) of 20 eyes imaged with Stratus OCT. Although BCVA correlated with macular thickening in the central 1 mm sub-field of the Stratus ETDRS (P=0.0005) and macular volume (central 3 mm area) on FD-OCT (P<0.0001), macular thickening on thickness map and volume correlated poorly with decrease in macular sensitivity on MP-1 (P=0.16). On FD-OCT, foveal morphological changes correlated best with decrease in BCVA, the strongest being central foveal thickness (P<0.0001). Other significant changes included blurring of the foveal inner segment-outer segment (IS-OS) junction and/or Verhoeff's membrane, vitreal displacement of foveal outer nuclear layer and foveal detachment (P<0.05). Foveal IS-OS junction disruption was seen in 25% of eyes on Stratus OCT but in none of the eyes on FD-OCT. CONCLUSION: FD-OCT allowed improved visualization of ERM and associated foveal morphological changes that correlated best with BCVA. Macular thickening correlated weakly with decreased macular function as assessed by MP-1.


Assuntos
Membrana Epirretiniana/fisiopatologia , Macula Lutea/patologia , Acuidade Visual/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Análise de Fourier , Humanos , Macula Lutea/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tomografia de Coerência Óptica/métodos , Campos Visuais/fisiologia
4.
Eye (Lond) ; 25(3): 279-89, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21293495

RESUMO

Inner and outer retinal morphology were quantified in vivo for 6 nonglaucomatous and 10 glaucomatous optic neuropathy patients. Custom, ultrahigh-resolution imaging modalities were used to evaluate segmented retinal layer thickness in 3D volumes (Fourier-domain optical coherence tomography), cone photoreceptor density (adaptive optics fundus camera), and the length of inner and outer segments of cone photoreceptors (adaptive optics-optical coherence tomography). Quantitative comparisons were made with age-matched controls, or by comparing affected and nonaffected retinal areas defined by changes in visual fields. The integrity of outer retinal layers on optical coherence tomography B-scans and density of cone photoreceptors were correlated with visual field sensitivity at corresponding retinal locations following reductions in inner retinal thickness. The photoreceptor outer segments were shorter and exhibited greater variability in retinal areas associated with visual field losses compared with normal or less affected areas of the same patient's visual field. These results demonstrate that nonglaucomatous and glaucomatous optic neuropathies are associated with outer retinal changes following long-term inner retinal pathology.


Assuntos
Glaucoma/patologia , Doenças do Nervo Óptico/patologia , Retina/anormalidades , Retina/patologia , Adulto , Idoso , Feminino , Glaucoma/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Nervo Óptico/fisiopatologia , Tomografia de Coerência Óptica/métodos , Campos Visuais/fisiologia , Adulto Jovem
5.
Eye (Lond) ; 23(2): 480-3, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18791549

RESUMO

OBJECTIVES: To investigate retinal microstructure of patients affected with malattia leventinese (MLVT) and mutation in the EFEMP1 gene using high-resolution optical coherence tomography (OCT). METHODS: Patients diagnosed with MLVT received a comprehensive eye exam, full-field and multifocal electroretinogram testing and imaging with a high-resolution Fourier domain OCT (Fd-OCT, UC Davis Medical Center, Davis, USA; axial resolution: 4.5 microm, acquisition speed: 9 frames s(-1), 1000 A scans s(-1)) combined with a flexible scanning head (Bioptigen Inc. Durham, NC, USA). RESULTS: Two related patients aged 30 and 60 years, with MLVT and identified c.R345W mutation in the EFEMP1 gene, were tested. Mother and daughter showed a variable phenotype with reduced vision function in the younger patient, whereas the mother had a 'form frustre'. Fd-OCT revealed extensive or focal sub-retinal pigment epithelium (RPE) deposits, separation of RPE and Bruch's membrane, and disruption of the photoreceptor outer and inner segment layers. No outer retinal changes were visible outside areas with sub-RPE deposits. CONCLUSION: Retinal structure in EFEMP1 retinal dystrophy is reflected by morphological changes within the RPE/Bruch's membrane complex with accumulation of sub-RPE material associated with disrupted photoreceptor integrity. The pattern of microstructural retinal abnormalities is similar but with a different extent in patients with variable phenotypes.


Assuntos
Proteínas da Matriz Extracelular/genética , Mutação , Retina/patologia , Degeneração Retiniana/genética , Degeneração Retiniana/patologia , Adulto , Lâmina Basilar da Corioide , Eletrorretinografia , Oftalmopatias Hereditárias/genética , Oftalmopatias Hereditárias/patologia , Oftalmopatias Hereditárias/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Degeneração Retiniana/fisiopatologia , Epitélio Pigmentado da Retina/patologia , Tomografia de Coerência Óptica , Acuidade Visual
7.
Opt Lett ; 33(1): 22-4, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18157245

RESUMO

We describe a novel instrument capable of acquiring, simultaneously, adaptive optics enhanced scanning laser ophthalmoscopy and optical coherence tomography (OCT) images of the human cone mosaic in vivo. The OCT system is based on transversal scanning of the sample with a line scan rate of 14 kHz, approximately 20 times faster than a previously reported instrument. We demonstrate the capability of this instrument with the measurement of the human cone spacing in perifoveal retina.


Assuntos
Aumento da Imagem/instrumentação , Microscopia Confocal/instrumentação , Oftalmoscópios , Células Fotorreceptoras Retinianas Cones/citologia , Técnica de Subtração/instrumentação , Tomografia de Coerência Óptica/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Óptica e Fotônica/instrumentação , Sensibilidade e Especificidade
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