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1.
Invest Ophthalmol Vis Sci ; 64(7): 31, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37342033

RESUMO

Purpose: To determine whether the ABCA4 retinopathy-associated variant p.Asn1868Ile (c.5603A>T) is associated with retinal structure or subclinical disease among the general population. Methods: UK Biobank participants of European ancestry with available spectral-domain optical coherence tomography (OCT) passing quality control metrics and exome sequencing data were included. Regression analyses using both linear and recessive models tested for the association between the p.Asn1868Ile variant and total retinal thickness, clinically relevant segmented layer thicknesses, and visual acuity. Further regression analyses were performed with automated quality control metrics to determine if the p.Asn1868Ile variant is associated with poor quality or abnormal scans. Results: Retinal layer segmentation and sequencing data for the p.Asn1868Ile variant were available for 26,558 participants, following exclusions. We identified no significant association between the p.Asn1868Ile variant and retinal thickness, any of the segmented layers, or visual acuity. There was also no significant difference for homozygous p.Asn1868Ile when tested under the assumption of a recessive model. No association was identified for any of the quality control metrics, and a χ2 test showed that participants with the p.Asn1868Ile variant were not more likely to be excluded during quality control due to poor quality scans (P = 0.56). Conclusions: The p.Asn1868Ile variant does not appear to affect the retinal structure or have pathogenic or subclinical effects on its own within the general population. The variant is likely to require other specific cis- or trans-acting modifying factors to cause ABCA4 retinopathy.


Assuntos
Bancos de Espécimes Biológicos , Doenças Retinianas , Humanos , Retina/patologia , Doenças Retinianas/genética , Doenças Retinianas/patologia , Tomografia de Coerência Óptica/métodos , Genótipo , Reino Unido , Transportadores de Cassetes de Ligação de ATP/genética
2.
Transl Vis Sci Technol ; 12(2): 25, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36795065

RESUMO

Purpose: The purpose of this study was to investigate the association between glycated hemoglobin (HbA1c) levels and retinal sub-layer thicknesses in people with and without diabetes. Methods: We included 41,453 UK Biobank participants aged 40 to 69 years old. Diabetes status was defined by self-report of diagnosis or use of insulin. Participants were categorized into groups: (1) those with HbA1c <48 mmol/mol were subdivided into quintiles according to normal range of HbA1c; (2) those previously diagnosed with diabetes with no evidence of diabetic retinopathy; and (3) undiagnosed diabetes: >48 mmol/mol. Total macular and retinal sub-layer thicknesses were derived from spectral-domain optical coherence tomography (SD-OCT) images. Multivariable linear regression was used to evaluate the associations between diabetes status and retinal layer thickness. Results: Compared with participants in the second quintile of the normal HbA1c range, those in the fifth quintile had a thinner photoreceptor layer thickness (-0.33 µm, P = 0.006). Participants with diagnosed diabetes had a thinner macular retinal nerve fiber layer (mRNFL; -0.58 µm, P < 0.001), photoreceptor layer thickness (-0.94 µm, P < 0.001), and total macular thickness (-1.61 µm, P < 0.001), whereas undiagnosed diabetes participants had a reduced photoreceptor layer thickness (-1.22 µm, P = 0.009) and total macular thickness (-2.26 µm, P = 0.005). Compared to participants without diabetes, those with diabetes had a thinner mRNFL (-0.50 µm, P < 0.001), photoreceptor layer thickness (-0.77 µm, P < 0.001), and total macular thickness (-1.36 µm, P < 0.001). Conclusions: Participants with higher HbA1c in the normal range had marginally thinner photoreceptor thickness, whereas those with diabetes (including undiagnosed diabetes) had meaningfully thinner retinal sublayer and total macular thickness. Translational Relevance: We showed that early retinal neurodegeneration occurs in people whose HbA1c levels are below the current diabetes diagnostic threshold; this might impact the management of pre-diabetes individuals.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Hemoglobinas Glicadas , Células Ganglionares da Retina , Bancos de Espécimes Biológicos , Valores de Referência , Retinopatia Diabética/diagnóstico por imagem , Retinopatia Diabética/epidemiologia , Reino Unido/epidemiologia , Tomografia de Coerência Óptica/métodos
3.
Retina ; 35(11): 2353-63, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26465617

RESUMO

PURPOSE: To describe a new method of retinal vascular perfusion density mapping using optical coherence tomography angiography and to compare current staging of diabetic retinopathy based on clinical features with a new grading scale based on perifoveal perfusion densities. METHODS: A retrospective review was performed on subjects with diabetic retinopathy and age-matched controls imaged with a spectral domain optical coherence tomography system (Optovue XR Avanti, Fremont, CA). Split-spectrum amplitude-decorrelation angiography (SSADA) generated optical coherence tomography angiograms of the superficial retinal capillaries, deep retinal capillaries, and choriocapillaris. Skeletonized optical coherence tomography angiograms were used to create color-coded perfusion maps and capillary perfusion density values for each image. Capillary perfusion density values were compared with clinical staging, and groups were compared using analysis of variance and Kruskal-Wallis analyses. RESULTS: Twenty-one control and 56 diabetic retinopathy eyes were imaged. Diabetic eyes were grouped according to clinical stage. Capillary perfusion density values from each microvascular layer were compared across all groups. Capillary perfusion density values were significantly lower in nearly all layers of all study groups compared with controls. Trend analysis showed a significant decrease in capillary perfusion density values as retinopathy progresses for most layers. CONCLUSION: Quantitative retinal vascular perfusion density mapping agreed closely with grading based on clinical features and may offer an objective method for monitoring disease progression in diabetic retinopathy.


Assuntos
Retinopatia Diabética/fisiopatologia , Angiofluoresceinografia , Vasos Retinianos/patologia , Tomografia de Coerência Óptica , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Capilares/fisiopatologia , Corioide/fisiopatologia , Retinopatia Diabética/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Retina/fisiopatologia , Estudos Retrospectivos , Acuidade Visual/fisiologia
4.
Graefes Arch Clin Exp Ophthalmol ; 253(9): 1557-64, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26255817

RESUMO

PURPOSE: To explore how optic disc perfusion varies in patients with open-angle glaucoma (OAG) and how this correlates with glaucoma severity. METHODS: We performed a prospective and cross-sectional observational study that included 62 eyes from 62 patients with OAG, divided into three groups according to their visual field (VF) results, and 20 eyes from 20 normal control subjects. Optic disc perfusion was studied using optical coherence tomography angiography (angio-OCT), and flow index and vessel density were determined. The VF, mean deviation (MD), pattern standard deviation (PSD), retinal nerve fiber layer (RNFL) thickness, and ganglion cell complex (GCC) thickness were also recorded. The potential associations between disc perfusion and VF defects or structural loss were analyzed. RESULTS: In OAG patients, the disc flow index and vessel density were significantly lower than in normal controls (all p<0.001) and were correlated with the severity of glaucoma. In OAG eyes, the flow index and vessel density were significantly correlated with MD, RNFL, and GCC thickness (all p<0.01), but were not in the normal controls. The receiver operating characteristic (ROC) curve analysis also revealed that disc flow index and vessel density had the power to differentiate normal eyes from eyes with OAG (under the ROC curves: 0.82 and 0.80, respectively). CONCLUSIONS: Angiograms demonstrated a reduced disc flow index and vessel density in glaucoma, and this reduction was closely related to GCC thickness. This indicated that measurement of disc perfusion by angio-OCT might be important for the monitoring of glaucoma.


Assuntos
Glaucoma de Ângulo Aberto/fisiopatologia , Disco Óptico/irrigação sanguínea , Vasos Retinianos/fisiologia , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Estudos Transversais , Feminino , Angiofluoresceinografia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Estudos Prospectivos , Fluxo Sanguíneo Regional , Células Ganglionares da Retina/patologia , Índice de Gravidade de Doença , Tomografia de Coerência Óptica , Transtornos da Visão/fisiopatologia , Campos Visuais/fisiologia , Adulto Jovem
5.
Biomed Opt Express ; 5(8): 2591-613, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25136488

RESUMO

Variability in illumination, signal quality, tilt and the amount of motion pose challenges for post-processing based 3D-OCT motion correction algorithms. We present an advanced 3D-OCT motion correction algorithm using image registration and orthogonal raster scan patterns aimed at addressing these challenges. An intensity similarity measure using the pseudo Huber norm and a regularization scheme based on a pseudo L0.5 norm are introduced. A two-stage registration approach was developed. In the first stage, only axial motion and axial tilt are coarsely corrected. This result is then used as the starting point for a second stage full optimization. In preprocessing, a bias field estimation based approach to correct illumination differences in the input volumes is employed. Quantitative evaluation was performed using a large set of data acquired from 73 healthy and glaucomatous eyes using SD-OCT systems. OCT volumes of both the optic nerve head and the macula region acquired with three independent orthogonal volume pairs for each location were used to assess reproducibility. The advanced motion correction algorithm using the techniques presented in this paper was compared to a basic algorithm corresponding to an earlier version and to performing no motion correction. Errors in segmentation-based measures such as layer positions, retinal and nerve fiber thickness, as well as the blood vessel pattern were evaluated. The quantitative results consistently show that reproducibility is improved considerably by using the advanced algorithm, which also significantly outperforms the basic algorithm. The mean of the mean absolute retinal thickness difference over all data was 9.9 um without motion correction, 7.1 um using the basic algorithm and 5.0 um using the advanced algorithm. Similarly, the blood vessel likelihood map error is reduced to 69% of the uncorrected error for the basic and to 47% of the uncorrected error for the advanced algorithm. These results demonstrate that our advanced motion correction algorithm has the potential to improve the reliability of quantitative measurements derived from 3D-OCT data substantially.

6.
Nat Med ; 17(2): 223-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21240263

RESUMO

The combination of intravital microscopy and animal models of disease has propelled studies of disease mechanisms and treatments. However, many disorders afflict tissues inaccessible to light microscopy in live subjects. Here we introduce cellular-level time-lapse imaging deep within the live mammalian brain by one- and two-photon fluorescence microendoscopy over multiple weeks. Bilateral imaging sites allowed longitudinal comparisons within individual subjects, including of normal and diseased tissues. Using this approach, we tracked CA1 hippocampal pyramidal neuron dendrites in adult mice, revealing these dendrites' extreme stability and rare examples of their structural alterations. To illustrate disease studies, we tracked deep lying gliomas by observing tumor growth, visualizing three-dimensional vasculature structure and determining microcirculatory speeds. Average erythrocyte speeds in gliomas declined markedly as the disease advanced, notwithstanding significant increases in capillary diameters. Time-lapse microendoscopy will be applicable to studies of numerous disorders, including neurovascular, neurological, cancerous and trauma-induced conditions.


Assuntos
Encefalopatias/patologia , Microscopia de Fluorescência/métodos , Imagem com Lapso de Tempo/métodos , Animais , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/patologia , Progressão da Doença , Feminino , Glioma/irrigação sanguínea , Glioma/patologia , Hipocampo/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microcirculação , Neovascularização Patológica/patologia , Células Piramidais/patologia
7.
Nat Methods ; 5(11): 935-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18836457

RESUMO

A central goal in biomedicine is to explain organismic behavior in terms of causal cellular processes. However, concurrent observation of mammalian behavior and underlying cellular dynamics has been a longstanding challenge. We describe a miniaturized (1.1 g mass) epifluorescence microscope for cellular-level brain imaging in freely moving mice, and its application to imaging microcirculation and neuronal Ca(2+) dynamics.


Assuntos
Microscopia de Fluorescência/instrumentação , Microscopia de Fluorescência/métodos , Miniaturização/métodos , Movimento/fisiologia , Animais , Encéfalo/fisiologia , Tecnologia de Fibra Óptica/instrumentação , Tecnologia de Fibra Óptica/métodos , Camundongos , Miniaturização/instrumentação , Fatores de Tempo
8.
Retina ; 27(4): 414-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17420691

RESUMO

BACKGROUND: Histopathological studies of acute multiple evanescent white dot syndrome (MEWDS) have not been reported because of the transient and benign nature of the disease. Ultrahigh resolution optical coherence tomography (UHR-OCT), capable of high resolution in vivo imaging, offers a unique opportunity to visualize retinal microstructure in the disease. METHODS: UHR-OCT images of the maculae of five patients with MEWDS were obtained and analyzed. Diagnosis was based on clinical presentation, examination, visual field testing, and angiography. RESULTS: UHR-OCT revealed disturbances in the photoreceptor inner/outer segment junction (IS/OS) in each of the five patients (six eyes) with MEWDS. In addition, thinning of the outer nuclear layer was seen in the case of recurrent MEWDS, suggesting that repeated episodes of MEWDS may result in photoreceptor atrophy. CONCLUSIONS: Subtle disruptions of the photoreceptor IS/OS are demonstrated in all eyes affected by MEWDS. UHR-OCT may be a useful adjunct to diagnosis and monitoring of MEWDS.


Assuntos
Macula Lutea/patologia , Células Fotorreceptoras de Vertebrados/patologia , Doenças Retinianas/diagnóstico , Tomografia de Coerência Óptica/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome
9.
Retina ; 26(9): 1034-41, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17151491

RESUMO

PURPOSE: To evaluate ultrahigh resolution optical coherence tomography (UHR OCT) for visualization of intraretinal layers, especially the photoreceptor inner segment and outer segment layers, in eyes with macular holes and after surgical intervention. METHODS: An UHR OCT system based on a titanium:sapphire laser was used, enabling in vivo cross-sectional retinal imaging with 3-micro m axial resolution. Typical, representative tomograms of 5 of 48 eyes from 36 patients demonstrated the potential of UHR OCT to detect morphologic changes in different stages of full-thickness macular holes and changes induced by surgical intervention. RESULTS: UHR OCT could detect subtle intraretinal changes in macular hole formation. Unprecedented visualization of photoreceptor impairment was achieved that appeared to be more extensive than the hole itself. Postoperatively, clinically closed holes showed restoration of the photoreceptor inner and outer segment layers of various extents, with residual disease in some eyes. CONCLUSION: In macular holes, UHR OCT allows for detection of even small morphologic changes of the retinal layers, especially the photoreceptor inner and outer segment layers. Therefore, it also represents a superior method to monitor the effect of surgical interventions. Preoperative photoreceptor impairment and the degree of postoperative restoration could possibly be associated with visual function. Hence, UHR OCT could lead to better understanding of macular hole pathogenesis and to more accurate disease prognosis.


Assuntos
Técnicas de Diagnóstico Oftalmológico , Retina/patologia , Perfurações Retinianas/diagnóstico , Tomografia de Coerência Óptica/métodos , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
Am J Ophthalmol ; 142(6): 945-52, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17157580

RESUMO

PURPOSE: To assess photoreceptor integrity in patients with retinitis pigmentosa (RP) and related diseases using ultra-high resolution optical coherence tomography (UHR-OCT) and to correlate foveal photoreceptor loss with visual acuity. DESIGN: Observational case series. METHODS: Nine eyes of nine patients with RP and related diseases were imaged with UHR-OCT at the ophthalmology clinic. Patients were diagnosed based on history, examination, fluorescein angiography, and electroretinography. Concurrently, 36 eyes of 36 normal subjects were imaged with UHR-OCT. Central foveal thickness (CFT) and foveal outer segment/pigment epithelium thickness (FOSPET) were defined and measured on UHR-OCT images in all subjects and were compared between the two groups using unpaired t tests. The two thickness measurements in RP patients were correlated with visual acuity using Pearson correlation and linear regression. RESULTS: UHR-OCT demonstrated macular photoreceptor thinning in all RP patients. The difference in CFT between RP patients and normal subjects was not statistically significant (P = .103), but the difference in FOSPET between the two groups was significant (P = .003). Visual acuity showed a fair correlation with CFT (Pearson r = -0.43, r(2) = 0.187, P = .245) and an excellent correlation with FOSPET (Pearson r = -0.942, r(2) = 0.887, P < .0001). CONCLUSIONS: In the current study using UHR-OCT, a new thickness measurement termed FOSPET is demonstrated to quantify photoreceptor loss. FOSPET was statistically thinner in patients with RP and related diseases than in normal eyes and showed correlation with logMAR visual acuity. FOSPET appears to be a probable predictor of visual acuity in RP.


Assuntos
Técnicas de Diagnóstico Oftalmológico , Células Fotorreceptoras de Vertebrados/patologia , Retinose Pigmentar/diagnóstico , Tomografia de Coerência Óptica/métodos , Adulto , Idoso , Eletrorretinografia , Feminino , Angiofluoresceinografia , Humanos , Masculino , Pessoa de Meia-Idade , Retinose Pigmentar/fisiopatologia , Acuidade Visual/fisiologia
12.
Invest Ophthalmol Vis Sci ; 47(12): 5522-8, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17122144

RESUMO

PURPOSE: To demonstrate high-speed, ultrahigh-resolution optical coherence tomography (OCT) for noninvasive, in vivo, three-dimensional imaging of the retina in rat and mouse models. METHODS: A high-speed, ultrahigh-resolution OCT system using spectral, or Fourier domain, detection has been developed for small animal retinal imaging. Imaging is performed with a contact lens and postobjective scanning. An axial image resolution of 2.8 mum is achieved with a spectrally broadband superluminescent diode light source with a bandwidth of approximately 150 nm at approximately 900-nm center wavelength. Imaging can be performed at 24,000 axial scans per second, which is approximately 100 times faster than previous ultrahigh-resolution OCT systems. High-definition and three-dimensional retinal imaging is performed in vivo in mouse and rat models. RESULTS: High-speed, ultrahigh-resolution OCT enabled high-definition, high transverse pixel density imaging of the murine retina and visualization of all major intraretinal layers. Raster scan protocols enabled three-dimensional volumetric imagingand comprehensive retinal segmentation algorithms allowed measurement of retinal layers. An OCT fundus image, akin to a fundus photograph was generated by axial summation of three-dimensional OCT data, thus enabling precise registration of OCT measurements to retinal fundus features. CONCLUSIONS: High-speed, ultrahigh-resolution OCT enables imaging of retinal architectural morphology in small animal models. OCT fundus images allow precise registration of OCT images and repeated measurements with respect to retinal fundus features. Three-dimensional OCT imaging enables visualization and quantification of retinal structure, which promises to allow repeated, noninvasive measurements to track disease progression, thereby reducing the need for killing the animal for histology. This capability can accelerate basic research studies in rats and mice and their translation into clinical patient care.


Assuntos
Retina/anatomia & histologia , Tomografia de Coerência Óptica/métodos , Animais , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Long-Evans , Tomografia de Coerência Óptica/instrumentação
13.
Ophthalmology ; 113(11): 2054.e1-14, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17074565

RESUMO

OBJECTIVE: To assess high-speed ultrahigh-resolution optical coherence tomography (OCT) image resolution, acquisition speed, image quality, and retinal coverage for the visualization of macular pathologies. DESIGN: Retrospective cross-sectional study. PARTICIPANTS: Five hundred eighty-eight eyes of 327 patients with various macular pathologies. METHODS: High-speed ultrahigh-resolution OCT images were obtained in 588 eyes of 327 patients with selected macular diseases. Ultrahigh-resolution OCT using Fourier/spectral domain detection achieves approximately 3-mum axial image resolutions, acquisition speeds of approximately 25 000 axial scans per second, and >3 times finer resolution and >50 times higher speed than standard OCT. Three scan protocols were investigated. The first acquires a small number of high-definition images through the fovea. The second acquires a raster series of high-transverse pixel density images. The third acquires 3-dimensional OCT data using a dense raster pattern. Three-dimensional OCT can generate OCT fundus images that enable precise registration of OCT images with the fundus. Using the OCT fundus images, OCT results were correlated with standard ophthalmoscopic examination techniques. MAIN OUTCOME MEASURES: High-definition macular pathologies. RESULTS: Macular holes, age-related macular degeneration, epiretinal membranes, diabetic retinopathy, retinal dystrophies, central serous chorioretinopathy, and other pathologies were imaged and correlated with ophthalmic examination, standard OCT, fundus photography, and fluorescein angiography, where applicable. High-speed ultrahigh-resolution OCT generates images of retinal pathologies with improved quality, more comprehensive retinal coverage, and more precise registration than standard OCT. The speed preserves retinal topography, thus enabling the visualization of subtle changes associated with disease. High-definition high-transverse pixel density OCT images improve visualization of photoreceptor and pigment epithelial morphology, as well as thin intraretinal and epiretinal structures. Three-dimensional OCT enables comprehensive retinal coverage, reduces sampling errors, and enables assessment of 3-dimensional pathology. CONCLUSIONS: High-definition 3-dimensional imaging using high-speed ultrahigh-resolution OCT improves image quality, retinal coverage, and registration. This new technology has the potential to become a useful tool for elucidating disease pathogenesis and improving disease diagnosis and management.


Assuntos
Imageamento Tridimensional , Macula Lutea , Doenças Retinianas/diagnóstico , Tomografia de Coerência Óptica/métodos , Tomografia de Coerência Óptica/normas , Adulto , Idoso , Estudos Transversais , Retinopatia Diabética/diagnóstico , Membrana Epirretiniana/diagnóstico , Feminino , Análise de Fourier , Humanos , Degeneração Macular/diagnóstico , Masculino , Perfurações Retinianas/diagnóstico , Retinose Pigmentar/diagnóstico , Estudos Retrospectivos
14.
Retina ; 26(6): 655-60, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16829808

RESUMO

OBJECTIVE: To demonstrate the ability to segment and analyze individual intraretinal layers, including the outer retinal complex (ORC; outer nuclear layer and inner and outer segments of the photoreceptor cells), in healthy eyes using images acquired from the latest commercially available optical coherence tomography (OCT) system (StratusOCT; Carl Zeiss Meditec, Inc., Dublin, CA) and from the ultrahigh resolution OCT (UHR-OCT) prototype. METHODS: Thirty-seven eyes from 37 healthy subjects underwent complete ophthalmologic examination using StratusOCT and UHR-OCT. ORC was identified and measured using a segmentation algorithm. RESULTS: For StratusOCT, mean weighted ORC thickness +/- SD was 91.1 +/- 7.9 microm, and mean weighted total retinal thickness +/- SD was determined to be 258.9 +/- 10.1 microm. For UHR-OCT, mean weighted ORC thickness +/- SD was 96.4 +/- 6.3 microm, and mean weighted total retinal thickness +/- SD was determined to be 263.4 +/- 9.2 mum. There was a higher rate of algorithm failure with UHR-OCT images. CONCLUSIONS: Photoreceptor layer thickness can be calculated by measuring ORC on OCT images using a macular segmentation algorithm. ORC values may serve as a useful objective parameter in determining the efficacy of various therapeutic modalities that target the photoreceptor layer in various diseases.


Assuntos
Células Fotorreceptoras de Vertebrados/citologia , Retina/anatomia & histologia , Tomografia de Coerência Óptica/métodos , Adulto , Idoso , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência
15.
Opt Lett ; 31(13): 2018-20, 2006 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16770418

RESUMO

Towards overcoming the size limitations of conventional two-photon fluorescence microscopy, we introduce two-photon imaging based on microelectromechanical systems (MEMS) scanners. Single crystalline silicon scanning mirrors that are 0.75 mm x 0.75 mm in size and driven in two dimensions by microfabricated vertical comb electrostatic actuators can provide optical deflection angles through a range of approximately16 degrees . Using such scanners we demonstrated two-photon microscopy and microendoscopy with fast-axis acquisition rates up to 3.52 kHz.


Assuntos
Lentes , Microscopia de Fluorescência por Excitação Multifotônica/instrumentação , Sistemas Computacionais , Desenho de Equipamento , Análise de Falha de Equipamento , Mecânica , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Miniaturização , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Arch Ophthalmol ; 124(6): 827-36, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16769836

RESUMO

OBJECTIVE: To evaluate retinal anatomy using ultrahigh-resolution optical coherence tomography (OCT) in eyes after successful surgical repair of full-thickness macular hole. METHODS: Twenty-two eyes of 22 patients were diagnosed as having macular hole, underwent pars plana vitrectomy, and had flat/closed macular anatomy after surgery, as confirmed with biomicroscopic and OCT examination findings. An ultrahigh-resolution-OCT system developed for retinal imaging, with the capability to achieve approximately 3-microm axial resolution, was used to evaluate retinal anatomy after hole repair. RESULTS: Despite successful closure of the macular hole, all 22 eyes had macular abnormalities on ultrahigh-resolution-OCT images after surgery. These abnormalities were separated into the following 5 categories: (1) outer foveal defects in 14 eyes (64%), (2) persistent foveal detachment in 4 (18%), (3) moderately reflective foveal lesions in 12 (55%), (4) epiretinal membranes in 14 (64%), and (5) nerve fiber layer defects in 3 (14%). CONCLUSIONS: With improved visualization of fine retinal architectural features, ultrahigh-resolution OCT can visualize persistent retinal abnormalities despite anatomically successful macular hole surgery. Outer foveal hyporeflective disruptions of the junction between the inner and outer segments of the photoreceptors likely represent areas of foveal photoreceptor degeneration. Moderately reflective lesions likely represent glial cell proliferation at the site of hole reapproximation. Thin epiretinal membranes do not seem to decrease visual acuity and may play a role in reestablishing foveal anatomy after surgery.


Assuntos
Técnicas de Diagnóstico Oftalmológico , Retina/patologia , Perfurações Retinianas/diagnóstico , Perfurações Retinianas/cirurgia , Tomografia de Coerência Óptica/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vitrectomia
18.
Ophthalmic Surg Lasers Imaging ; 37(2): 138-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16583635

RESUMO

A case of crystalline retinopathy caused by prolonged ingestion of an oral tanning agent containing canthaxanthine is described. Color fundus photography and ultrahigh-resolution optical coherence tomography were performed.


Assuntos
Antioxidantes/efeitos adversos , Cantaxantina/efeitos adversos , Retina/efeitos dos fármacos , Doenças Retinianas/induzido quimicamente , Doenças Retinianas/diagnóstico , Tomografia de Coerência Óptica/métodos , Diagnóstico Diferencial , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Retina/patologia
19.
Ophthalmology ; 113(4): 666-72, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16581427

RESUMO

OBJECTIVE: To assess microstructural changes in the retina that may explain incomplete visual recovery after anatomically successful repair of rhegmatogenous retinal detachments (RD) using ultrahigh-resolution optical coherence tomography (UHR OCT). DESIGN: Retrospective observational case series. PARTICIPANTS: Seventeen patients with decreased visual acuity after RD repair. Twelve patients had macula-involving and 5 had macula-sparing RDs. METHODS: The UHR OCT prototype capable of approximately 3 mum axial resolution was developed for clinical use. The UHR OCT images through the center of the fovea in 17 patients with visual complaints after RD surgery were obtained. Patients were either postoperative patients from the New England Eye Center or tertiary referrals. Baseline visual acuity, preoperative lens status, location of retinal detachment, macular involvement, and postoperative visual acuity were recorded. MAIN OUTCOME MEASURES: The UHR OCT images after RD repair. RESULTS: The UHR OCT images were obtained 1 to 84 months (median, 5 months) postoperatively. The mean preoperative logarithm of the minimum angle of resolution (logMAR) visual acuity was 1.37 (Snellen equivalent, 20/390). The mean postoperative logMAR visual acuity was 0.48 (Snellen equivalent, 20/60). Anatomical abnormalities that were detected included distortion of the photoreceptor inner/outer segments (IS/OS) junction in 14 of 17 patients (82%), epiretinal membranes in 10 of 17 patients (59%), residual subretinal fluid in 3 of 17 patients (18%), and cystoid macular edema in 2 of 17 patients (12%). Of the 5 patients with preoperative macula-on detachments, 4 had distortion of the outer retina after RD repair. CONCLUSIONS: The higher resolution of UHR OCT facilitates imaging of the IS/OS junction. Therefore, UHR OCT is able to confirm prior histopathologic findings that damage to photoreceptor outer segments may occur as a consequence of retinal detachment. This may explain poor postoperative visual acuity in eyes with anatomically successful repair.


Assuntos
Células Fotorreceptoras de Vertebrados/patologia , Complicações Pós-Operatórias , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/cirurgia , Tomografia de Coerência Óptica , Transtornos da Visão/diagnóstico , Acuidade Visual , Adulto , Idoso , Criocirurgia , Técnicas de Diagnóstico Oftalmológico , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Recurvamento da Esclera , Vitrectomia
20.
Ophthalmology ; 113(3): 388-97, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16513456

RESUMO

OBJECTIVES: To define optical coherence tomographic (OCT) criteria for the diagnosis of a lamellar macular hole, and to increase understanding of lamellar hole pathogenesis by examining fine anatomic features using ultrahigh-resolution optical coherence tomography (UHR OCT). DESIGN: Retrospective observational case series. PARTICIPANTS: Nineteen eyes of 18 patients with lamellar holes were imaged with UHR OCT between 2002 and 2004. METHODS: A UHR OCT system was developed for use in the ophthalmology clinic. All 6 UHR OCT images for each eye imaged were examined. Lamellar holes were diagnosed based on a characteristic OCT appearance. Criteria for the OCT diagnosis of a lamellar hole were as follows: (1) irregular foveal contour; (2) break in the inner fovea; (3) intraretinal split; and (4) intact foveal photoreceptors. From 1205 eyes of 664 patients imaged with UHR OCT, and retrospectively reviewed, 19 eyes of 18 patients were diagnosed with a lamellar hole based on these criteria. All 19 eyes were also imaged with standard resolution OCT. Their charts were retrospectively reviewed. MAIN OUTCOME MEASURES: Standard and ultrahigh-resolution OCT images. RESULTS: On chart review, clinical diagnosis of a lamellar hole was made in only 7 of 19 eyes (37%). Twelve of 19 eyes (63%) had an epiretinal membrane (ERM) on clinical examination. Ten of 19 eyes (53%) had a posterior vitreous detachment. On UHR OCT, 17 of 19 eyes (89%) had ERMs. Eleven ERMs had an unusual thick appearance on UHR OCT. Due to poor visual acuity, 4 eyes underwent vitrectomy. Only 1 of 4 surgeries (25%) was visually and anatomically successful. Another eye improved visually, but a lamellar hole persisted. One eye progressed to a full-thickness macular hole preoperatively, which reopened after surgery. One eye developed a full-thickness hole postoperatively. CONCLUSIONS: The diagnosis of a lamellar hole can be made based on OCT criteria, which could be applied to both standard and ultrahigh-resolution OCT. The increased resolution of UHR OCT sheds light on the pathogenesis of the lamellar hole. Epiretinal membranes were visualized on UHR OCT in the majority of eyes. Many ERMs had an unusual thick appearance on UHR OCT, which may represent either trapped vitreous or posterior hyaloid, and may help stabilize retinal anatomy. Conversely, ERM contraction may play a role in lamellar hole formation. Vitrectomy surgery was anatomically and visually successful in only 1 of 4 patients, suggesting caution when performing vitrectomy on lamellar holes.


Assuntos
Perfurações Retinianas/diagnóstico , Tomografia de Coerência Óptica , Corpo Vítreo , Idoso , Progressão da Doença , Membrana Epirretiniana/diagnóstico , Membrana Epirretiniana/fisiopatologia , Membrana Epirretiniana/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Oftalmológicos , Recidiva , Perfurações Retinianas/cirurgia , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Vitrectomia , Descolamento do Vítreo/diagnóstico
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