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2.
N Engl J Med ; 382(18): 1687-1695, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32286748

RESUMO

BACKGROUND: Nonophthalmologist physicians do not confidently perform direct ophthalmoscopy. The use of artificial intelligence to detect papilledema and other optic-disk abnormalities from fundus photographs has not been well studied. METHODS: We trained, validated, and externally tested a deep-learning system to classify optic disks as being normal or having papilledema or other abnormalities from 15,846 retrospectively collected ocular fundus photographs that had been obtained with pharmacologic pupillary dilation and various digital cameras in persons from multiple ethnic populations. Of these photographs, 14,341 from 19 sites in 11 countries were used for training and validation, and 1505 photographs from 5 other sites were used for external testing. Performance at classifying the optic-disk appearance was evaluated by calculating the area under the receiver-operating-characteristic curve (AUC), sensitivity, and specificity, as compared with a reference standard of clinical diagnoses by neuro-ophthalmologists. RESULTS: The training and validation data sets from 6779 patients included 14,341 photographs: 9156 of normal disks, 2148 of disks with papilledema, and 3037 of disks with other abnormalities. The percentage classified as being normal ranged across sites from 9.8 to 100%; the percentage classified as having papilledema ranged across sites from zero to 59.5%. In the validation set, the system discriminated disks with papilledema from normal disks and disks with nonpapilledema abnormalities with an AUC of 0.99 (95% confidence interval [CI], 0.98 to 0.99) and normal from abnormal disks with an AUC of 0.99 (95% CI, 0.99 to 0.99). In the external-testing data set of 1505 photographs, the system had an AUC for the detection of papilledema of 0.96 (95% CI, 0.95 to 0.97), a sensitivity of 96.4% (95% CI, 93.9 to 98.3), and a specificity of 84.7% (95% CI, 82.3 to 87.1). CONCLUSIONS: A deep-learning system using fundus photographs with pharmacologically dilated pupils differentiated among optic disks with papilledema, normal disks, and disks with nonpapilledema abnormalities. (Funded by the Singapore National Medical Research Council and the SingHealth Duke-NUS Ophthalmology and Visual Sciences Academic Clinical Program.).


Assuntos
Aprendizado Profundo , Fundo de Olho , Redes Neurais de Computação , Oftalmoscopia/métodos , Papiledema/diagnóstico , Fotografação , Retina/diagnóstico por imagem , Algoritmos , Área Sob a Curva , Conjuntos de Dados como Assunto , Diagnóstico Diferencial , Humanos , Valor Preditivo dos Testes , Curva ROC , Retina/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade
3.
Nat Commun ; 11(1): 831, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-32047156

RESUMO

Visual features extracted by retinal circuits are streamed into higher visual areas (HVAs) after being processed along the visual hierarchy. However, how specialized neuronal representations of HVAs are built, based on retinal output channels, remained unclear. Here, we addressed this question by determining the effects of genetically disrupting retinal direction selectivity on motion-evoked responses in visual stages from the retina to HVAs in mice. Direction-selective (DS) cells in the rostrolateral (RL) area that prefer higher temporal frequencies, and that change direction tuning bias as the temporal frequency of a stimulus increases, are selectively reduced upon retinal manipulation. DS cells in the primary visual cortex projecting to area RL, but not to the posteromedial area, were similarly affected. Therefore, the specific connectivity of cortico-cortical projection neurons routes feedforward signaling originating from retinal DS cells preferentially to area RL. We thus identify a cortical processing stream for motion computed in the retina.


Assuntos
Neurônios/fisiologia , Retina/fisiologia , Córtex Visual/fisiologia , Vias Visuais/fisiologia , Animais , Proteínas do Citoesqueleto/genética , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Percepção de Movimento/fisiologia , Orientação/fisiologia , Estimulação Luminosa , Retina/diagnóstico por imagem
4.
Nat Commun ; 11(1): 130, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31913272

RESUMO

Center-involved diabetic macular edema (ci-DME) is a major cause of vision loss. Although the gold standard for diagnosis involves 3D imaging, 2D imaging by fundus photography is usually used in screening settings, resulting in high false-positive and false-negative calls. To address this, we train a deep learning model to predict ci-DME from fundus photographs, with an ROC-AUC of 0.89 (95% CI: 0.87-0.91), corresponding to 85% sensitivity at 80% specificity. In comparison, retinal specialists have similar sensitivities (82-85%), but only half the specificity (45-50%, p < 0.001). Our model can also detect the presence of intraretinal fluid (AUC: 0.81; 95% CI: 0.81-0.86) and subretinal fluid (AUC 0.88; 95% CI: 0.85-0.91). Using deep learning to make predictions via simple 2D images without sophisticated 3D-imaging equipment and with better than specialist performance, has broad relevance to many other applications in medical imaging.


Assuntos
Retinopatia Diabética/diagnóstico por imagem , Edema Macular/diagnóstico por imagem , Idoso , Aprendizado Profundo , Retinopatia Diabética/genética , Feminino , Humanos , Imageamento Tridimensional , Edema Macular/genética , Masculino , Pessoa de Meia-Idade , Mutação , Fotografação , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica
5.
PLoS One ; 15(1): e0226840, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923239

RESUMO

PURPOSE: To test the hypothesis that imaging biomarkers are useful for evaluating in vivo rod photoreceptor cell responses to a mitochondrial protonophore. METHODS: Intraperitoneal injections of either the mitochondrial uncoupler 2,4 dinitrophenol (DNP) or saline were given to mice with either higher [129S6/eVTac (S6)] or lower [C57BL/6J (B6)] mitochondrial reserve capacities and were studied in dark or light. We measured: (i) the external limiting membrane-retinal pigment epithelium region thickness (ELM-RPE; OCT), which decreases substantially with upregulation of a pH-sensitive water removal co-transporter on the apical portion of the RPE, and (ii) the outer retina R1 (= 1/(spin lattice relaxation time (T1), an MRI parameter proportional to oxygen / free radical content. RESULTS: In darkness, baseline rod energy production and consumption are relatively high compared to that in light, and additional metabolic stimulation with DNP provoked thinning of the ELM-RPE region compared to saline injection in S6 mice; ELM-RPE thickness was unresponsive to DNP in B6 mice. Also, dark-adapted S6 mice given DNP showed a decrease in outer retina R1 values compared to saline injection in the inferior retina. In dark-adapted B6 mice, transretinal R1 values were unresponsive to DNP in superior and inferior regions. In light, with its relatively lower basal rod energy production and consumption, DNP caused ELM-RPE thinning in both S6 and B6 mice. CONCLUSIONS: The present results raise the possibility of non-invasively evaluating the mouse rod mitochondrial energy ecosystem using new DNP-assisted OCT and MRI in vivo assays.


Assuntos
Imagem por Ressonância Magnética , Mitocôndrias/metabolismo , Retina/citologia , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica , Adaptação Fisiológica/efeitos da radiação , Animais , Biomarcadores/metabolismo , Escuridão , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Retina/fisiologia , Retina/efeitos da radiação
6.
PLoS One ; 15(1): e0227641, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929571

RESUMO

Retinal pigment epithelium (RPE) transplantation for the treatment of macular degeneration has been studied for over 30 years. Human clinical trials have demonstrated that RPE monolayers exhibit improved cellular engraftment and survival compared to single cell suspensions. The use of a scaffold facilitates implantation of a flat, wrinkle-free, precisely placed monolayer. Scaffolds currently being investigated in human clinical trials are non-degradable which results in the introduction of a chronic foreign body. To improve RPE transplant technology, a degradable scaffold would be desirable. Using human fibrin, we have generated scaffolds that support the growth of an RPE monolayer in vitro. To determine whether these scaffolds are degraded in vivo, we developed a surgical approach that delivers a fibrin hydrogel implant to the sub-retinal space of the pig eye and determined whether and how fast they degraded. Using standard ophthalmic imaging techniques, the fibrin scaffolds were completely degraded by postoperative week 8 in 5 of 6 animals. Postmortem histologic analysis confirmed the absence of the scaffold from the subretinal space at 8 weeks, and demonstrated the reattachment of the neurosensory retina and a normal RPE-photoreceptor interface. When mechanical debridement of a region of native RPE was performed during implantation surgery degradation was accelerated and scaffolds were undetectable by 4 weeks. These data represent the first in situ demonstration of a fully biodegradable scaffold for use in the implantation of RPE and other cell types for treatment of macular degeneration and other retinal degenerative diseases.


Assuntos
Implantes Absorvíveis , Fibrina , Retina/cirurgia , Tecidos Suporte , Animais , Desenho de Equipamento , Feminino , Retina/citologia , Retina/diagnóstico por imagem , Degeneração Retiniana/cirurgia , Sus scrofa
7.
PLoS One ; 15(1): e0227718, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929582

RESUMO

PURPOSE: To quantify the structural and perfusion changes in choriocapillaris in chronic central serous chorioretinopathy after half-dose photodynamic therapy by using spectral-domain optical coherence tomography and optical coherence tomography angiography. METHODS: This retrospective interventional case series examined the eyes of patients with central serous chorioretinopathy. Patients underwent full ophthalmic examinations, including spectral-domain optical coherence tomography and angiography, prior to and 1, 3, and 6 months after the treatment. Clinical and tomographic features of the choriocapillaris and choroidal thickness and vascular changes were evaluated by assessing flow signal voids. RESULTS: All 56 eyes of 56 patients showed complete resolution of subretinal fluid at 3 months after photodynamic therapy. The best-corrected visual acuity significantly improved at 6 months (p<0.001). The central subfield thickness, subfoveal choroidal thickness, subfoveal choroidal large vessel layer thickness, and mean total area of flow signal voids decreased significantly at 6 months (all p values < 0.001), but the subfoveal choriocapillaris layer thickness did not change significantly at 6 months (p≥0.16). Multivariate analysis revealed positive linear correlations of the central subfield thickness and subfoveal choroidal large vessel layer thickness with the mean total area of flow signal voids at 6 months (p<0.001). There was a negative linear correlation between the subfoveal choriocapillaris layer and the mean total area of flow signal voids at 6 months (p = 0.013). CONCLUSION: Half-dose photodynamic therapy improved the anatomic and functional outcomes of central serous chorioretinopathy, induced subfoveal choroidal thickness thinning, and increased choriocapillaris perfusion. In addition, the recovery of the subfoveal choriocapillaris layer thickness and improved choriocapillaris perfusion were closely associated.


Assuntos
Coriorretinopatia Serosa Central/diagnóstico por imagem , Coriorretinopatia Serosa Central/tratamento farmacológico , Corioide/efeitos dos fármacos , Corioide/diagnóstico por imagem , Fármacos Fotossensibilizantes/uso terapêutico , Adulto , Angiografia , Corioide/irrigação sanguínea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fotoquimioterapia , Fármacos Fotossensibilizantes/administração & dosagem , Retina/diagnóstico por imagem , Retina/efeitos dos fármacos , Estudos Retrospectivos , Tomografia de Coerência Óptica
8.
BMC Med Genet ; 21(1): 16, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31969119

RESUMO

BACKGROUND: Autosomal recessive bestrophinopathy (ARB) is a retinal degenerative disorder caused by BEST1 mutations with autosomal recessive inheritance. We aim to map a comprehensive genomic and metabolomic profile of a consanguineous Chinese family with ARB. METHODS: Ophthalmic examinations were performed on the affected patients with ARB. The proband was screened for potential causative mutations in a panel with 256 known retinal disease genes by using target capture sequencing. The related mutation was further validated and segregated in the family members by Sanger sequencing. In silico prediction tools were used for pathogenicity assessment. A UHPLC-MS/MS metabolomic analysis was performed to explore the disease-associated metabolic feature. RESULTS: The affected patients from this family were characterized by low vision, the presence of subretinal fluid, macular edema, and hyperopia with coincidental angle closure. DNA sequencing identified a novel missense mutation in the BEST1 gene c.646G > A (p.Val216Ile) of the proband. Sanger sequencing further confirmed the mutation. The missense mutation was co-segregation across the pedigree and predicted to be deleterious by SIFT (0.017). The blood metabolic profiles were highly similar among all family members probably because of the same lifestyle, habitat and genomic background. However, ARB patients presented a significant deregulation of metabolites, such as citric acid, L-Threonic acid, and eicosapentaenoic acid. CONCLUSIONS: We identified a novel disease-associated variant in the BEST1 gene as well as a disease-specific metabolic feature in familial ARB. Our findings helped improve the understanding of ARB mechanisms.


Assuntos
Bestrofinas/genética , Anormalidades do Olho/genética , Oftalmopatias Hereditárias/genética , Doenças Retinianas/genética , Distrofias Retinianas/genética , Canais de Cloreto/genética , Eletrorretinografia , Anormalidades do Olho/fisiopatologia , Oftalmopatias Hereditárias/fisiopatologia , Feminino , Humanos , Masculino , Mutação , Mutação de Sentido Incorreto/genética , Linhagem , Fenótipo , Retina/diagnóstico por imagem , Retina/patologia , Doenças Retinianas/fisiopatologia , Distrofias Retinianas/diagnóstico por imagem , Distrofias Retinianas/fisiopatologia , Análise de Sequência de DNA
10.
Nat Biomed Eng ; 4(1): 18-27, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31873211

RESUMO

Owing to the invasiveness of diagnostic tests for anaemia and the costs associated with screening for it, the condition is often undetected. Here, we show that anaemia can be detected via machine-learning algorithms trained using retinal fundus images, study participant metadata (including race or ethnicity, age, sex and blood pressure) or the combination of both data types (images and study participant metadata). In a validation dataset of 11,388 study participants from the UK Biobank, the fundus-image-only, metadata-only and combined models predicted haemoglobin concentration (in g dl-1) with mean absolute error values of 0.73 (95% confidence interval: 0.72-0.74), 0.67 (0.66-0.68) and 0.63 (0.62-0.64), respectively, and with areas under the receiver operating characteristic curve (AUC) values of 0.74 (0.71-0.76), 0.87 (0.85-0.89) and 0.88 (0.86-0.89), respectively. For 539 study participants with self-reported diabetes, the combined model predicted haemoglobin concentration with a mean absolute error of 0.73 (0.68-0.78) and anaemia an AUC of 0.89 (0.85-0.93). Automated anaemia screening on the basis of fundus images could particularly aid patients with diabetes undergoing regular retinal imaging and for whom anaemia can increase morbidity and mortality risks.


Assuntos
Anemia/diagnóstico por imagem , Retina/diagnóstico por imagem , Aprendizado Profundo , Feminino , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC
11.
Am J Ophthalmol ; 212: 43-56, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31862446

RESUMO

PURPOSE: To determine clear-cut distinctions between tractional and exudative intraretinal cystoid spaces subtypes. DESIGN: Retrospective, multicenter, observational case series. METHODS: A cohort of patients diagnosed with intraretinal cystoid spaces and imaged with optical coherence tomography (OCT), fluorescein angiography (FA), blue fundus autofluorescence (BFAF), en face OCT, and OCT angiography (OCT-A) was included in the study. All images were qualitatively and quantitatively evaluated. RESULTS: In this study were included 72 eyes of 69 patients. Exudative intraretinal cystoid spaces (36/72 eyes, 50%) displayed a "petaloid" morphology as seen with en face OCT, FA, and BFAF. Tractional intraretinal cystoid spaces (24/72 eyes, 33.3%), displayed a radial "spoke-wheel" en face OCT pattern. There was no leakage with FA and BFAF did not reveal specific patterns. Eyes with full-thickness macular hole (FTMH, 12/72 eyes, 16.7%) displayed a "sunflower" en face OCT appearance. FTMH showed OCT, OCT-A, and BFAF features of both exudative and tractional cystoid spaces, but without any FA leakage. Inner nuclear layer (INL) thickness was significantly lower in tractional cystoid spaces (P < .001). There were a greater number of INL cystoid spaces in both the exudative and FTMH subgroups (P = .001). The surface area of INL cystoid spaces was significantly lower in the tractional subgroup (P < .001). There was a significant reduction of the microvascular density in eyes with exudative vs tractional (P = .002) and FTMH (P < .001) subgroups. CONCLUSIONS: Exudative and tractional intraretinal cystoid spaces displayed characteristic multimodal imaging features and they may represent 2 different pathologic conditions with equally different clinical implications.


Assuntos
Edema Macular/patologia , Imagem Multimodal/métodos , Retina/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Retinopatia Diabética/diagnóstico por imagem , Retinopatia Diabética/patologia , Feminino , Angiofluoresceinografia/métodos , Fundo de Olho , Humanos , Edema Macular/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Imagem Óptica/métodos , Retina/diagnóstico por imagem , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos
13.
BMC Ophthalmol ; 19(1): 260, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852464

RESUMO

BACKGROUND: Foldable capsular vitreous body (FCVB) was designed to treat severe retinal detachment. The aim of this study was to evaluate the efficacy and safety of the implantation of foldable capsular vitreous body in 1-year follow-up. METHODS: A retrospective analysis was conducted for 20 patients with severe ocular trauma or silicone oil (SO) dependent eyes underwent vitrectomy and FCVB implantation in a 1-year follow-up. All treated eyes were peformed clinical examinations involved the visual acuity (VA) examination, Goldmann applanation tonometer, noncontact specular microscopy, fundus photography, B-Scan examination and optical coherence tomography (OCT). The groups were compared with t-test and the McNemar - Bowker test. RESULTS: In 1-year follow-up, 20 eyes were evaluated in the study. FCVB well supported the vitreous retina in all treated eyes, and 6 treated eyes achieved retinal reattachment 12 months after FCVB implantation. There were no significant differences in VA before and after FCVB implantation (P = 1.000). In addition, the postoperative IOP markedly elevated from the preoperative IOP of 12.90 ± 7.06 mmHg to 15.15 ± 3.36 mmHg (P = 0.000017). The intraocular pressure (IOP) of 10 eyes maintained at a normal level after surgeries. The other 10 eyes showed slightly lower IOP within the acceptable level. Though two patients developed keratopathy and ocular inflammation respectively, other treated eyes were symmetric with fellow eyes showing satisfactory appearance. Moreover, there was no SO emulsification or leakage happened in the observation. CONCLUSIONS: FCVB implantation was an effective and safe treatment in the eyes with severe retinal detachment.


Assuntos
Traumatismos Oculares/cirurgia , Próteses e Implantes , Implantação de Prótese , Retina/lesões , Descolamento Retiniano/cirurgia , Corpo Vítreo , Adolescente , Adulto , Idoso , Materiais Biocompatíveis , Criança , Pré-Escolar , Traumatismos Oculares/diagnóstico por imagem , Traumatismos Oculares/fisiopatologia , Feminino , Seguimentos , Humanos , Pressão Intraocular/fisiologia , Masculino , Pessoa de Meia-Idade , Retina/diagnóstico por imagem , Descolamento Retiniano/diagnóstico por imagem , Descolamento Retiniano/fisiopatologia , Estudos Retrospectivos , Ruptura , Tomografia de Coerência Óptica , Tonometria Ocular , Resultado do Tratamento , Acuidade Visual/fisiologia , Vitrectomia
14.
PLoS One ; 14(12): e0226728, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31869361

RESUMO

BACKGROUND: Optical coherence tomography is commonly used to measure the retinal nerve fibre layer thickness in both normal and diseased eyes; however, variation among normal eyes is common and may limit the usefulness of the results. The aim of this study was to explore the interocular asymmetries in retinal nerve fibre layer thickness in a group of normal eyes and to investigate the influence of blood vessel diameter on local retinal nerve fibre layer thickness. METHODS: In this prospective study, retinal nerve fibre layer thickness and blood vessel diameter across 100 healthy participants were measured using two optical coherence tomography instruments. Individuals were categorised into two groups based on the presence or absence of interocular retinal nerve fibre layer thickness asymmetry beyond the 75th percentile of all participants. RESULTS: The superonasal sectoral retinal nerve fibre layer thickness was significantly greater in the left eye compared to the right, across all three sectors. Mean blood vessel diameter showed a corresponding difference in thickness at one of the superonasal sectors. Linear regression showed a positive and moderate correlation between blood vessel diameter and focal retinal nerve fibre layer thickness. This trend persisted across both arteries and veins, but veins showed larger variability between left and right eye in participants with marked superonasal retinal nerve fibre layer asymmetry. CONCLUSION: Retinal nerve fibre layer thickness and blood vessel diameter vary significantly between eyes even in healthy individuals. These asymmetries in a normal population should be taken into consideration when interpreting the retinal nerve fibre layer thickness measurements from optical coherence tomography to assist in distinguishing normal variations from disease.


Assuntos
Retina/diagnóstico por imagem , Doenças Retinianas/diagnóstico por imagem , Células Ganglionares da Retina/patologia , Vasos Retinianos/diagnóstico por imagem , Adulto , Idoso , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Retina/patologia , Doenças Retinianas/patologia , Células Ganglionares da Retina/citologia , Vasos Retinianos/anatomia & histologia , Vasos Retinianos/patologia , Tomografia de Coerência Óptica/métodos , Adulto Jovem
15.
Adv Exp Med Biol ; 1185: 133-137, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31884601

RESUMO

Retinal imaging has advanced to enable noninvasive in vivo visualization of macular photoreceptors with cellular resolution. Images of retinal structure are best interpreted in the context of visual function, but clinical measures of visual function lack resolution on the scale of individual cells. Combined with cross-sectional measures of retinal structure acquired with optical coherence tomography (OCT), macular photoreceptor function can be evaluated using visual acuity and fundus-guided microperimetry, but the resolution of these measures is limited to relatively large retinal areas. By incorporating adaptive optics correction of aberrations in light entering and exiting the pupil, individual photoreceptors can be visualized and stimulated to assess structure and function. Discrepancy between structural images and visual function can shed light on the origin of visible features and their relation to visual function. Dysflective cones, cones with abnormal waveguiding properties on confocal adaptive optics scanning laser ophthalmoscopy (AOSLO) images and measurable function, provide insight into the visual significance of features in retinal images and may facilitate identification of patients who could benefit from therapies.


Assuntos
Retina/diagnóstico por imagem , Retina/fisiopatologia , Células Fotorreceptoras Retinianas Cones/patologia , Fundo de Olho , Humanos , Oftalmoscopia , Tomografia de Coerência Óptica
16.
Biomed Res Int ; 2019: 7436293, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31886247

RESUMO

Purpose: To compare the effective fields of the Optos 200Tx® and Clarus 500™, two ultra-widefield ophthalmoscopes, based on their ability to image branches of retinal vessel in the four retinal quadrants. Methods: Ninety retinal images from 90 patients with various eye diseases were studied. All patients had undergone 200° retinal imaging to obtain a single image of Optos (O) and the montage of two images of the Clarus (C). The highest number of traceable vessel branches in the four retinal quadrants was determined by two masked raters. An image was classified as "O > C" when the number of identifiable branch was greater in the Optos than the Clarus, as "O = C" when the number was equal and as "O < C" when the number was fewer in the Optos than the Clarus. Results: The appearance probability of "O > C" was significantly higher at the upper temporal quadrant than "O < C" (p < 0.01 for both raters). In contrast, the appearance probability of "O < C" was significantly higher at the lower nasal quadrant than "O > C" (p < 0.01 for both raters). There were no significant differences in the appearance probability between "O > C" and "O < C" at the other two retinal quadrants (p > 0.50 for both raters). Conclusions: These results demonstrate that the effective field of views was different between the two devices at different retina quadrants. Further studies are needed to clarify possible factors such as artifacts by the eyelashes, differences in the depth of focus, motion of the device, and different locations of the images on the effective field of views.


Assuntos
Oftalmoscópios , Feminino , Fundo de Olho , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Probabilidade , Retina/diagnóstico por imagem
17.
Adv Exp Med Biol ; 1185: 151-155, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31884604

RESUMO

Spectral-domain optical coherence tomography (SD-OCT) produces high-resolution images of retinal cross sections and is becoming a method of choice for in vivo analyses of retinal morphology in rodents. We have adopted this technology to identify and analyze alterations of retinal structure, particularly those with regional and subtle changes. In this technical brief, we will demonstrate the use of SD-OCT in identifying subtle changes in retinal structure and morphology due to the effect of mosaic gene deletion in conditional knockout mice and of uneven distribution of intravitreally delivered compounds, review the application of SD-OCT in measuring pathological lesion volumes, and discuss the major benefits of SD-OCT technology over the traditional histological methods.


Assuntos
Retina/diagnóstico por imagem , Tomografia de Coerência Óptica , Animais , Camundongos , Camundongos Knockout , Retina/patologia
18.
PLoS One ; 14(12): e0227207, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31887186

RESUMO

PURPOSE: To describe the retinal contour in optical coherence tomography (OCT) images, and report the relationship between retinal contour and axial length. METHODS: Retinal contour was defined by the path of the retinal pigment epithelial (RPE) line in macular and extra-macular OCTs of 70 eyes of 70 participants recruited from ophthalmology clinics in South Australia. The shape of this contour was described by the best-fit curvature (K), and Fourier analysis of the difference between K and the RPE. The Fourier transformation was summarised by total difference (sumdiff), maximum single frequency difference (MaxE), and root mean square difference (rmse) between each B scan residual and the average normal. All-of-eye and regional median and interquartile range (IQR) shape features were correlated to axial length. RESULTS: Retinal shape irregularity measured by Fourier transformation correlated with axial length: all-of-eye median and IQR sumdiff (ρ = 0.66 and ρ = 0.60 respectively), median and IQR rmse (ρ = 0.67 and ρ = 0.48), median MaxE (ρ = 0.61), and IQR K (ρ = 0.61) all correlated with axial length. Correlation with axial length was also seen in these parameters for 11 of 17 regions. Retinal irregularity was greatest at the macula and in inferior regions. CONCLUSION: Retinal OCT shape becomes increasingly irregular as axial length increases. The range of curvature correlates with axial length, while median curvature does not.


Assuntos
Comprimento Axial do Olho/fisiopatologia , Miopia/diagnóstico , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica , Adulto , Idoso , Idoso de 80 Anos ou mais , Comprimento Axial do Olho/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Análise de Fourier , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Miopia/fisiopatologia , Retina/fisiopatologia , Austrália do Sul
19.
Adv Exp Med Biol ; 1185: 569-574, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31884672

RESUMO

The goal of this study was to quantitatively assess retinal thickness using spectral domain optical coherence tomography (SD-OCT) after subretinal implantation of human embryonic stem cell-derived retinal pigment epithelium in a porcine model. The implant is called CPCB-RPE1 for the California Project to Cure Blindness-Retinal Pigment Epithelium 1. Data were derived from previous experiments on 14 minipigs that received either subretinal implantation of CPCB-RPE1 (n = 11) or subretinal bleb formation alone (sham; n = 3) using previously described methods and procedures (Brant Fernandes et al. Ophthalmic Surg Lasers Imaging Retina 47:342-51, 2016; Martynova et al. (2016) Koss et al. Graefes Arch Clin Exp Ophthalmol 254:1553-65, 2016; Hu et al. Ophthalmic Res 48:186-91, 2016; Martynova et al. ARVO Abstract 2016. SD-OCT retinal thickness (RT) and sublayer thickness over the implant were compared with topographically similar preimplantation regions as described previously Martynova et al. ARVO Abstract 2016. Imaging results were compared to postmortem histology using hematoxylin-eosin staining. RT overlying the CPCB-RPE1 postimplantation was not significantly different from preimplantation (308 ± 72 µm vs 292 ± 41 µm; p = 0.44). RT was not significantly different before and after implantation in any retinal sublayer at 1 month. Histology demonstrated grossly normal retinal anatomy as well as photoreceptor interdigitation with RPE.


Assuntos
Células-Tronco Embrionárias Humanas/transplante , Retina/diagnóstico por imagem , Epitélio Pigmentado da Retina/citologia , Tomografia de Coerência Óptica , Animais , California , Humanos , Suínos
20.
Invest Ophthalmol Vis Sci ; 60(14): 4896-4903, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31752019

RESUMO

Purpose: The geometry of retinal nerve fibers may be altered with myopia, a known risk factor for glaucoma. Recent developments in high resolution imaging have enabled direct visualization of nerve fiber bundles at the temporal raphe with clinical hardware, providing evidence that this area is sensitive to glaucomatous damage. Here, we test the hypothesis that nerve fiber geometry is altered by myopia, both at the temporal raphe and surrounding the optic nerve head. Methods: Seventy-eight healthy individuals participated, with refractive errors distributed between emmetropia and high myopia (+0 to -13 DS). Custom high-density OCT scans were used to visualize RFNL bundle trajectory at the temporal raphe. A standard clinical OCT protocol was used to assess papillary minimum rim width (MRW) and peripapillary retinal nerve fiber layer (RNFL) thickness. Results: Measures of raphe shape-including position, orientation, and width-did not depend significantly on axial length. In 7.5% of subjects, the raphe was rotated sufficiently that inversion of structure-function mapping to visual field space is predicted in the nasal step region. Low concordance to ISNT and related rules was observed in myopia (e.g., for RNFL, 8% of high axial myopes compared with 67% of emmetropes). Greater robustness to refractive error was observed for the IT rule. Conclusions: High density OCT scans enabled visualization of marked interindividual variation in temporal raphe geometry; however, these variations were not well predicted by degree of myopia as represented by axial length. That said, degree of myopia was associated with abnormal thickness profiles for the papillary and peripapillary nerve fiber layer.


Assuntos
Comprimento Axial do Olho/patologia , Emetropia/fisiologia , Miopia/patologia , Fibras Nervosas/patologia , Nervo Óptico/patologia , Retina/patologia , Células Ganglionares da Retina/patologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Nervo Óptico/diagnóstico por imagem , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica , Campos Visuais , Adulto Jovem
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