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1.
Curr Opin Ophthalmol ; 31(3): 199-206, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32168003

RESUMO

PURPOSE OF REVIEW: This article reviews emerging technologies in retinal imaging, including their scientific background, clinical implications and future directions. RECENT FINDINGS: Fluorescence lifetime imaging ophthalmoscopy is a technology that will reveal biochemical and metabolic changes of the retina at the cellular level. Optical coherence tomography is evolving exponentially toward higher resolution, faster speed, increased portability and more cost effective. Adaptive optics scanning laser ophthalmoscopy fluorescein angiography will provide unprecedented detail of the retinal vasculature down to the level of capillaries, enabling earlier and more sensitive detection of retinal vascular diseases. SUMMARY: Continued developments in retinal imaging focus on improved resolution, faster speed and noninvasiveness, while providing new information on the structure-function relationship of the retina inclusive of metabolic activity at the cellular level.


Assuntos
Diagnóstico por Imagem/tendências , Doenças Retinianas/diagnóstico por imagem , Vasos Retinianos/diagnóstico por imagem , Angiofluoresceinografia/métodos , Humanos , Oftalmoscopia , Tomografia de Coerência Óptica/métodos
2.
PLoS One ; 15(2): e0229213, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32078656

RESUMO

PURPOSE: Von Hippel-Lindau (VHL) disease is a hereditary disorder that can lead to ophthalmic manifestations, including retinal capillary hemangioma (RCH). The diagnosis of RCH is often guided by wide-field fluorescein angiography. In some cases, optical coherence tomography angiography (OCT-A) serves as a non-invasive alternative to FA. Herein, we used OCT-A to examine the macular microvasculature in patients with VHL disease. SUBJECTS: Subjects were selected from patients with a diagnosis of VHL. The control group included eyes without retinal diagnosis from patients with an episode of unilateral retinal detachment or trauma and age ≤ 50 years old. METHODS: Subjects were scanned on the Optovue RTVue-XR device to acquire 3mm x 3mm OCT-A images of the superficial (SCP) and deep capillary plexus (DCP). SCP and DCP vessel density (VD) were calculated after the images were binarized. Furthermore, for subjects with RCH, each OCT-A image was divided equally into four quadrants. SCP and DCP VD of quadrants with RCH were compared to those without RCH. T-tests were performed for statistical analysis. RESULTS: 67 eyes with a history of VHL disease were included as study subjects, while 16 eyes were included as controls. Significant increases in VD were found in patients with VHL disease for both the SCP (p = 0.0441) and DCP (p = 0.0344). When comparing quadrants with associated RCH development to those without, we found no significant difference in SCP VD (p = 0.160) or DCP VD (p = 0.484). CONCLUSIONS: OCT-A can detect changes in the retinal microvasculature in the macula of patients with VHL disease. OCT-A imaging may be an additional tool for screening and early detection of patients at risk of developing ocular complications of VHL disease. Future studies should explore subtle progression on OCT-A associated with the pathogenesis and development of RCH, particularly with larger scan patterns.


Assuntos
Angiofluoresceinografia/métodos , Doenças Retinianas/diagnóstico , Vasos Retinianos/patologia , Tomografia de Coerência Óptica/métodos , Doença de von Hippel-Lindau/complicações , Adulto , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Doenças Retinianas/etiologia , Vasos Retinianos/diagnóstico por imagem , Estudos Retrospectivos , Acuidade Visual , Doença de von Hippel-Lindau/diagnóstico por imagem
3.
Optom Vis Sci ; 97(2): 110-120, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32011584

RESUMO

SIGNIFICANCE: Foveal hypoplasia is described clinically by the absence of a foveal pit and subsequent reduction in visual acuity. Optical coherence tomography angiography provides precise segmentation of the retinal vascular supply demonstrating the vascular perfusion in affected patients. Preservation of perfusion is linked to visual acuity and function. PURPOSE: This case report describes a patient with foveal hypoplasia and preservation of visual acuity with preserved retinal capillary density of the superficial and deep capillary plexuses on optical coherence tomography angiography. In addition, the diagnostic findings of foveal hypoplasia as seen on optical coherence tomography angiography will be described. CASE REPORT: A 25-year-old Caucasian female with history of foveal hypoplasia presented to the clinic for evaluation. She had no other visual, ocular, or systemic complaints. Her ocular history included Duane syndrome, accommodative insufficiency, and traumatic brain injury. Her medical history included cardiac ablation secondary to supraventricular tachycardia, gall bladder removal, maxillary sinus cyst, and a history of migraines. Best-corrected visual acuity was 20/15 in the right and left eyes. Funduscopic examination was unremarkable. Spectral domain optical coherence tomography revealed absence of the anatomical foveal pit with normal inner retinal morphology. Optical coherence tomography angiography confirmed a decreased foveal avascular zone; however, a vascular density analysis showed normal perfusion to the inner retinal plexuses. CONCLUSIONS: Optical coherence tomography angiography is a rapid, noninvasive imaging modality that provides excellent insight into the microvasculature supply to the retina and choroid. As such, it allows for an in-depth analysis into the pathophysiology behind certain conditions such as foveal hypoplasia.


Assuntos
Anormalidades do Olho/diagnóstico por imagem , Fóvea Central/anormalidades , Acuidade Visual/fisiologia , Adulto , Capilares/diagnóstico por imagem , Capilares/patologia , Feminino , Angiofluoresceinografia/métodos , Humanos , Vasos Retinianos/diagnóstico por imagem , Vasos Retinianos/patologia , Tomografia de Coerência Óptica/métodos , Transtornos da Visão/fisiopatologia
4.
PLoS One ; 15(1): e0227175, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923188

RESUMO

BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) is associated with an increased risk of myocardial infarction and stroke but it remains unclear how to identify microvascular changes in this population. OBJECTIVES: We hypothesized that simple non-mydriatic retinal photography is feasible and can be used to assess microvascular damage in COPD. METHODS: Novel Vascular Manifestations of COPD was a prospective study comparing smokers with and without COPD, matched for age. Non-mydriatic, retinal fundus photographs were assessed using semi-automated software. RESULTS: Retinal images from 24 COPD and 22 control participants were compared. Cases were of similar age to controls (65.2 vs. 63.1 years, p = 0.38), had significantly lower Forced Expiratory Volume in one second (FEV1) (53.4 vs 100.1% predicted; p < 0.001) and smoked more than controls (41.7 vs. 29.6 pack years; p = 0.04). COPD participants had wider mean arteriolar (155.6 ±15 uM vs. controls [142.2 ± 12 uM]; p = 0.002) and venular diameters (216.8 ±20.7 uM vs. [201.3± 19.1 uM]; p = 0.012). Differences in retinal vessel caliber were independent of confounders, odds ratios (OR) = 1.08 (95% confidence intervals [CI] = 1.02, 1.13; p = 0.007) and OR = 1.05 (CI = 1.01, 1.09; p = 0.011) per uM increase in arteriolar and venular diameter respectively. FEV1 remained significantly associated with retinal vessel dilatation r = -0.39 (p = 0.02). CONCLUSIONS: Non-mydriatic retinal imaging is easily facilitated. We found significant arteriole and venous dilation in COPD compared to age-matched smokers without COPD associated with lung function independent of standard cardiovascular risk factors. Retinal microvascular changes are known to be strongly associated with future vascular events and retinal photography offers potential to identify this risk. TRIAL REGISTRATION: clinicaltrials.gov NCT02060292.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Microvasos/diagnóstico por imagem , Fotomicrografia/métodos , Doença Pulmonar Obstrutiva Crônica/complicações , Doenças Retinianas/diagnóstico por imagem , Doenças Retinianas/etiologia , Vasos Retinianos/diagnóstico por imagem , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Viabilidade , Feminino , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Vasos Retinianos/patologia , Fumantes , Fumar/efeitos adversos
5.
Eur J Ophthalmol ; 30(1): 48-57, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30516077

RESUMO

PURPOSE: To quantify vascular and structural macular variables in healthy eyes and to investigate correlations between these variables and age using optical coherence tomography angiography. MATERIALS AND METHODS: A total of 261 eyes of 261 subjects with normal fundus were included. Central macular thickness, ganglion cell layer to inner plexiform layer thickness, outer retina layer thickness, subfoveal choroidal thickness, and choroidal vascularity index were measured using optical coherence tomography. Foveal avascular zone area, vascular density, and flow void area were measured using optical coherence tomography angiography. RESULTS: Vascular density in the superficial capillary plexus was correlated with central macular thickness, ganglion cell layer to inner plexiform layer thickness, and outer retina layer thickness (P < 0.001, P = 0.004, and P < 0.001, respectively). Vascular density in the deep capillary plexus was correlated with central macular thickness and outer retina layer thickness (P = 0.003 and P = 0.001, respectively). Vascular density of choriocapillaris was correlated with vascular density of superficial capillary plexus and deep capillary plexus (P < 0.001 and P = 0.001, respectively). CONCLUSION: Vascular density of choriocapillaris varies with retinal vascular density rather than the structure of choroid using optical coherence tomography angiography. In contrast, retinal vascular density changes as the retinal structure. Our results provide more information about the relationship between retina and choroid.


Assuntos
Corioide/irrigação sanguínea , Vasos Retinianos/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Corioide/diagnóstico por imagem , Estudos Transversais , Feminino , Angiofluoresceinografia/métodos , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Vasos Retinianos/diagnóstico por imagem , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Adulto Jovem
7.
Klin Monbl Augenheilkd ; 237(1): 95-111, 2020 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-31745942

RESUMO

OCTA expands the spectrum of multimodal retinal imaging as a non-invasive procedure. Subtraction analysis of two temporally dense and identical B-scan images only show changes corresponding to the flow in the blood vessels. Freely selectable segmentation visualization of different layers of the retina, RPE, choriocapillars and choroid. By means of manufacturer-specific quantification options and 3-D representation changes in findings under a therapy can be well represented. At present, OCTA is still bound to a corresponding B-scan. The OCTA is currently not a substitute for the conventional FAG, as it can give no indication of permeability disorders and fluid movements over time and the image is still very limited. These limitations will soon disappear as a result of rapid technological development and provide the OCTA with a permanent place in the multimodal imaging of the retina. With further development, new biomarkers for therapy and re-treatment may be safely defined for some diseases.


Assuntos
Vasos Retinianos , Tomografia de Coerência Óptica , Corioide , Angiofluoresceinografia , Humanos , Retina , Vasos Retinianos/diagnóstico por imagem
8.
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
9.
Ophthalmic Surg Lasers Imaging Retina ; 50(12): 802-807, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31877227

RESUMO

BACKGROUND AND OBJECTIVE: To describe a method for averaging ocular coherence tomography angiography (OCTA) images using a commercially available photo editing software: Adobe Photoshop CC 2017. PATIENTS AND METHODS: This single-center study assessed the feasibility of using Adobe Photoshop as an OCTA image averaging tool. Three 3.0 mm × 3.0 mm OCTA images from each eye were obtained using commercially available OCTA devices. Captured OCTA images were exported in high-resolution TIFF format, imported as an image stack, aligned using an automated function, and averaged by creating a Smart Object using Photoshop CC 2017 software. In conjunction with qualitative assessment, the main outcome of the study was image grader preferences with respect to clarity of the foveal avascular zone (FAZ), blood vessel delineation, and the ability to identify abnormal vasculature. RESULTS: After removing OCTA scans with significant image distortion, 25 sets of images were included in the analysis. Adobe Photoshop CC 2017 successfully aligned and averaged all images of the superficial and deep retinal plexuses that contained a minimum 40% overlap. Three independent retinal specialists found the averaged images to be slightly or definitely preferable to the original 87%, 89%, and 69% of the time with respect to clarity of the FAZ, clarity of blood vessel delineation, and the ability to identify abnormal vasculature, respectively. CONCLUSIONS: Adobe Photoshop CC 2017 is an excellent tool for image averaging, producing high-quality resulting OCTA images. As an easily accessible software, Photoshop has the potential for use in a diversity of pathological conditions. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:802-807.].


Assuntos
Angiofluoresceinografia , Processamento de Imagem Assistida por Computador/métodos , Telangiectasia Retiniana/diagnóstico por imagem , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica , Estudos de Viabilidade , Humanos , Software
10.
PLoS One ; 14(12): e0226629, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31887149

RESUMO

PURPOSE: To quantify vessel tortuosity and fractal dimension of the superficial capillary plexus (SCP) of the macula in different stages of diabetic retinopathy (DR), and following panretinal photocoagulation (PRP) using optical coherence tomography angiography (OCTA). METHODS: 75 eyes of 75 subjects were divided into five groups; healthy controls, diabetes with no clinical DR, non-proliferative diabetic retinopathy (NPDR), proliferative diabetic retinopathy (PDR) and patients who received PRP for PDR (PDR+PRP).For vessel tortuosity, SCP slabs from 3x3 mm macular OCTA scans were processed using imageJ (NIH, USA), where large perifoveal vessels were traced and their length was measured with tortuosity calculated as the ratio between the actual length and the straight Euclidean length. For fractal dimension, SCP slabs were processed and imported to Fractalyse (ThéMA, France), where box-counting analyses produced fractal dimension values. RESULTS: We found a significant difference in vessel tortuosity and fractal dimension between the five groups (one-way ANOVA, p < 0.001both). NPDR and PDR had significantly more tortuous vessels and lower fractal dimension compared to healthy controls (Tukey HSD: p = 0.02, 0.015,0.015 and <0.001, respectively). Fractal dimension was also significantly lower in NPDR and PDR compared to eyes with no clinical DR (p <0.001 both), and in PDR compared to NPDR (p = 0.014). Following PRP, vessel tortuosity was significantly lower and fractal dimension was higher in PDR+PRP compared to PDR (p = 0.001 and 0.031, respectively). CONCLUSIONS: We used macular OCTA scans to demonstrate significantly higher perifoveal large vessel tortuosity, and lower fractal dimension in NPDR and PDR compared to healthy controls. Vessel tortuosity shows more dramatic normalization than fractal dimension and could be explored as a sensitive marker for successful PRP.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Retinopatia Diabética/diagnóstico por imagem , Fotocoagulação a Laser/métodos , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Adulto , Idoso , Estudos de Casos e Controles , Retinopatia Diabética/patologia , Feminino , Fractais , Humanos , Masculino , Pessoa de Meia-Idade , Vasos Retinianos/patologia , Estudos Retrospectivos , Resultado do Tratamento
11.
Invest Ophthalmol Vis Sci ; 60(14): 4830-4837, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31747685

RESUMO

Purpose: We investigate macular perfusion and the systemic and ocular associations in a population-based setting. Methods: In this cross-sectional study, 2018 adults residing in Hong Kong underwent detailed ophthalmic examinations after consenting to participate. Macular perfusion was measured with optical coherence tomography angiography (OCTA) using the split-spectrum amplitude decorrelation angiography algorithm. The parafoveal flow index and vessel area density were quantified using automated custom-built software. Results: Of the 2018 participants, the OCTA measurements were available for 1940, and 1631 (84.1%) had good quality scans. The right eyes of these 1631 participants (43.1% men) were included for final analysis. Mean age was 49.8 years (range, 18-92 years). Mean global macular vessel density was 47.3% and 55.1% for the superficial and deep retinal layers, respectively. In multivariate analysis, lower superficial vessel density remained significantly associated with lower signal strength index (SSI; P < 0.001, standardized ß = 0.607) and male sex (P < 0.001, ß = 0.162), and borderline associated with older age (P = 0.09, ß = -0.045) and longer axial length (AL; P = 0.09, ß = -0.037), while lower deep layer vessel density was significantly associated with lower SSI (P < 0.001, standardized ß = 0.667), longer AL (P < 0.001, ß = -0.097), and higher creatinine (P < 0.001, ß = -0.072). Conclusions: This large population-based study provided normative OCTA data of macular vessel density and demonstrated that a lower superficial retinal vessel density was significantly associated with lower SSI and male sex, while a lower deep layer retinal vessel density was significantly associated with lower SSI, longer AL, and higher level of creatinine. These associations must be considered when interpreting clinical quantitative OCTA data.


Assuntos
Angiofluoresceinografia , Macula Lutea/irrigação sanguínea , Vasos Retinianos/anatomia & histologia , Tomografia de Coerência Óptica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Capilares/anatomia & histologia , Capilares/diagnóstico por imagem , Creatinina/sangue , Estudos Transversais , Feminino , Angiofluoresceinografia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fluxo Sanguíneo Regional/fisiologia , Retina/fisiologia , Vasos Retinianos/diagnóstico por imagem , Lâmpada de Fenda , Tomografia de Coerência Óptica/métodos , Adulto Jovem
12.
Klin Monbl Augenheilkd ; 236(12): 1445-1450, 2019 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-31671461

RESUMO

OBJECTIVE: A comparison between automated and manual measurements of a foveal avascular zone in optical coherence tomography angiography (OCTA) in patients with diabetic retinopathy (DR). MATERIAL AND METHODS: Consecutive patients with non-proliferative DR were included in this study. All patients received an OCTA, with a 3 × 3 mm scan of the macular region taken with the Zeiss OCT CIRRUS 5000 with the AngioPlex module. The size of the foveal avascular zone (FAZ) was determined both manually and with the help of the automated measurement metrics. Next, the measurements obtained using manual and automated methods were compared. In addition, the circularity index determined in metrics was examined for correlations with the size and area of the FAZ. RESULTS: Thirty-four eyes from 28 patients with non-proliferative diabetic retinopathy with a mean age of 63 years were included. The mean size of the foveal avascular zone was 0.34 ± 0.12 mm2 (0.08 - 0.65 mm2) for manual evaluation and 0.23 ± 0.11 mm2 (range 0.03 - 0.49 mm2) in metrics. The circularity index in metrics averaged 0.58 and showed a statistically significant correlation with the size of the manually measured FAZ. CONCLUSION: There was a comparable result for the size of the FAZ in both measurement methods. Automated measurements with metrics can reliably represent changes in the FAZ for most patients, based on the calculated area, as well as on the circumference and the circularity index.


Assuntos
Angiofluoresceinografia , Macula Lutea , Tomografia de Coerência Óptica , Fóvea Central , Humanos , Pessoa de Meia-Idade , Vasos Retinianos/diagnóstico por imagem
13.
Zhonghua Yan Ke Za Zhi ; 55(10): 757-762, 2019 Oct 11.
Artigo em Chinês | MEDLINE | ID: mdl-31607064

RESUMO

Objective: To observe changes in foveal avascular zone(FAZ) and capillary plexus in idiopathic macular epiretinal membrane (IMEM) in optical coherence tomography angiography (OCTA) and analyze their correlation with the visual acuity. Methods: Cross-sectional study. 42 patients (15 Males and 27 females, age 64.8) from the Eye Hospital of Wenzhou Medical University were included with 51 eyes diagnosed as IMEM (IMEM group), and 23 normal eyes (9 Males and 14 females, control group). All patients received the examination of fissure lamp combined with fundus pre-set lens, best corrected visual acuity (BCVA), OCT angiography (OCTA) and fundus photo. OCTA was performed on 3 mm× 3 mm sections centred on the fovea. The software automatically measured the superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density(VD) and retinal thickness(RT) and FAZ area. The IMEM eyes were compared with the normal eyes and correlation between the parameters of OCTA and BCVA was analyzed in IMEM. Independent-sample t test and MannWhitney test were used for comparison between groups, and Spearman test was used for correlation analysis. Results: LogMAR BCVA in the IMEM group was 0.40(0.15, 0.70), in the control group was 0.10(0.05, 0.22). FAZ area of IMEM group was (0.09±0.05) mm(2), while that of control group was (0.34±0.13)mm(2).Compared with the control group, in IMEM group, the BCVA was worse (Z=-4.443, P<0.001), FAZ area was smaller (t=-9.198, P<0.001), RT was increased (P<0.001), The foveal DCP and SCP vessel density was increased (t=4.280, 9.079, P<0.01), The parafoveal DCP vessel density was decreased (P<0.05), The parafoveal SCP vessel density was decreased in superior, inferior and nasal side (t=-2.759, Z=-3.998, Z=-2.108; P<0.05). The BCVA was negatively correlated with FAZ area (r=-0.337, P=0.017), positively correlated with center macular thickness (r=0.324, P=0.020). The BCVA was no correlated with foveal VD and parafoveal DCP vessel density (P>0.05), but correlated with SCP vessel density(P<0.05). Conclusions: In the IMEM eyes the BCVA was worse, FAZ area was smaller, foveal vessel density was increased and the parafoveal vessel density was decreased compared with the normal eyes. The smaller the FAZ area, the smaller foveal SCP vessel density, the poorer BCVA. There was no correlation between BCVA and DCP vessel density. Changes in VD in IMEM eyes may lead to changes in vision. (Chin J Ophthalmol, 2019, 55:757-762).


Assuntos
Membrana Epirretiniana/diagnóstico por imagem , Angiofluoresceinografia/métodos , Fóvea Central/irrigação sanguínea , Vasos Retinianos/diagnóstico por imagem , Vasos Retinianos/patologia , Tomografia de Coerência Óptica , Angiografia , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Estudos Transversais , Feminino , Fóvea Central/diagnóstico por imagem , Humanos , Masculino , Acuidade Visual
14.
BMC Ophthalmol ; 19(1): 204, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31601186

RESUMO

BACKGROUND: The metabolic activity of retina is higher than other human tissues and is crucial to the vision. Cynomolgus macaques is widely used in ophthalmic disease research. The evaluation and comparison of macular and optic disc vascular circulation parameters between normal adult cynomolgus macaques and healthy adult humans using OCT-A can promote better use of nonhuman primate models in studies of ophthalmic vascular disease. METHODS: Twelve normal adult cynomolgus macaques with a mean age of 4.91 ± 0.43 years were studied for data collection. The macula of 28 adult healthy humans (14 males and 14 females), with a mean age of 25.11 ± 6.21 years and the optic discs of 9 adult healthy humans (4 males and 5 females) with a mean age of 28.56 ± 6.78 years were measured. The vessel density (VD) was measured using an RTVue XR with AngioVue. The scan sizes of the macular and optic discs were 3 × 3 mm and 4.5 × 4.5 mm, respectively. RESULTS: OCT-A can image the superficial and deep capillary plexuses and radial peripapillary capillary network. In RPC layer of the optic disc, the VD in the nasal quadrant was lower than the VD in the inferior temporal quadrant. Similarities and significant differences in VD between healthy humans and cynomolgus macaques were obtained using OCT-A. CONCLUSIONS: This study provides normal vascular parameters for adult cynomolgus macaques using OCT-A to help establish an optical parameter database for cynomolgus macaques and compare VD between healthy humans and cynomolgus macaques to promote choroid-retinopathy research. TRIAL REGISTRATION: Current Controlled Trials NCT03692169 , retrospectively registered on 26 sept 2018.


Assuntos
Angiofluoresceinografia/métodos , Disco Óptico/irrigação sanguínea , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Adulto , Animais , Feminino , Fundo de Olho , Humanos , Macaca fascicularis , Masculino , Modelos Animais , Valores de Referência
15.
Exp Eye Res ; 189: 107856, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31654619

RESUMO

The foveal avascular zone (FAZ) is the capillary-free area in the central macula with high photoreceptor density and metabolic activity. In the present study we measured the superficial and deep macular foveal avascular zone (sFAZ, dFAZ) in the eyes of healthy adults of both sexes of various ages ranging from 10 to 69 years using optical coherence tomography angiography (OCT-A) in order to evaluate the influence of gender and age on FAZ size. A cross-sectional study was carried out in 240 eyes of 120 healthy subjects, OCT-A was performed by means of a Topcon swept source OCT. sFAZ and dFAZ areas were measured using the IMAGEnet6 software package. Subjects were grouped by age (six groups) and gender. The mean ±â€¯sd age of the subjects was 39.2 ±â€¯17.4 years (50% women, 50% men), ranging from 10 to 69 years. The overall mean sFAZ size in women (0.297 ±â€¯0.110 mm2) was significantly larger (p = 0.002) than in men (0.254 ±â€¯0.098 mm2). Similarly, the overall mean dFAZ in women (0.322 ±â€¯0.111 mm2) was significantly larger (p < 0.001) than in men (0.273 ±â€¯0.099). However, when analyzed by age group, these gender differences appeared only in groups younger than 20 years old and older than 50 years old. Men did not show differences among the six age groups. In women, for both sFAZ and dFAZ, the 20-29 year old group had a smaller FAZ size than the 50-59 year old group. In conclusion for both sFAZ and dFAZ, women have larger areas than men, but this occurs only in the young and old age groups. In men, age does not seem to influence the size of the FAZ, but in women, both sFAZ and dFAZ were significantly smaller in younger than in older ages. These results suggest that retinal changes in retinal structure caused by aging may be different in woman than in men, probably reflecting the more hormonal variations known to exist with age in women.


Assuntos
Envelhecimento , Angiofluoresceinografia/métodos , Fóvea Central/diagnóstico por imagem , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Adolescente , Adulto , Fatores Etários , Idoso , Capilares/diagnóstico por imagem , Criança , Estudos Transversais , Feminino , Fundo de Olho , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Adulto Jovem
16.
Invest Ophthalmol Vis Sci ; 60(12): 3887-3896, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31529120

RESUMO

Purpose: To investigate foveal avascular zone (FAZ) changes in the superficial (SCP) and deep (DCP) capillary plexuses in beta-thalassemia major (BTM) patients, as shown in optical coherence tomography angiography. Methods: Nonrandomized, comparative case series of 54 eyes of 27 BTM patients and 46 eyes of 23 healthy controls, utilizing an automated FAZ detection algorithm. Measurements included FAZ area and FAZ shape descriptors (convexity, circularity, and contour temperature). Results were compared between the two groups, and correlated to iron load and chelation therapy parameters. Results: SCP and DCP FAZ area were not significantly different between the control and BTM groups (P = 0.778 and P = 0.408, respectively). The same was true regarding SCP FAZ convexity (P = 0.946), circularity (P = 0.838), and contour temperature (P = 0.907). In contrast, a statistically significant difference was detected between controls and BTM group regarding DCP FAZ convexity (P = 0.013), circularity (P = 0.010), and contour temperature (P = 0.014). Desferrioxamine dosage was strongly correlated to the DCP area (r = 0.650, P = 0.05) and liver magnetic resonance imaging/T2-star to DCP circularity (r = -0.492, P = 0.038). Correlations were also revealed between urine Fe excretion and DCP convexity (r = 0.531, P = 0.019), circularity (r = 0.661, P = 0.002), and contour temperature (r = -0.591, P = 0.008). Conclusions: Retinal capillary plexuses and especially DCP seem to present unique morphologic changes in BTM patients, not in the FAZ area, but in specific shape descriptors, indicating minor but detectable FAZ changes. These changes correlate well with iron load and chelation therapy parameters. Their clinical importance and pathophysiologic implications remain to be elucidated through further studies.


Assuntos
Fóvea Central/irrigação sanguínea , Vasos Retinianos/patologia , Talassemia beta/diagnóstico , Adulto , Capilares/patologia , Desferroxamina/administração & dosagem , Feminino , Ferritinas/sangue , Angiofluoresceinografia/métodos , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Vasos Retinianos/diagnóstico por imagem , Sideróforos/administração & dosagem , Tomografia de Coerência Óptica/métodos , Talassemia beta/sangue , Talassemia beta/tratamento farmacológico
17.
Ideggyogy Sz ; 72(7-8): 273-277, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31517460

RESUMO

Cerebral cavernous malformations (CCMs) represent a relatively rare and heterogeneous clinical entity with mutations identified in three genes. Both sporadic and familial forms have been reported. We present a young female patient with episodic paresthesia and headaches, but without acute neurological deficits. Her mother had a hemorrhaged cavernoma surgically removed 21 years ago. Cranial magnetic resonance imaging revealed multiple cavernous malformations in the size of a few millimeters and the ophthalmologic exam detected retinal blood vessel tortuosity in the proband. Targeted exome sequencing analysis identified a nonsense mutation in exon 16 of the KRIT1 gene, which resulted in a premature stop codon and a truncated protein underlying the abnormal development of cerebral and retinal blood vessels. This mutation with pathogenic significance has been reported before. Our case points to the importance of a thorough clinical and molecular work up despite the uncertain neurological complaints, since life style recommendations, imaging monitoring and genetic counseling may have major significance in the long term health of the patient.


Assuntos
Hemangioma Cavernoso do Sistema Nervoso Central/diagnóstico , Proteína KRIT1/genética , Vasos Retinianos/diagnóstico por imagem , Feminino , Cefaleia/etiologia , Hemangioma Cavernoso do Sistema Nervoso Central/diagnóstico por imagem , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Humanos , Imagem por Ressonância Magnética , Mutação , Parestesia/etiologia , Linhagem , Deleção de Sequência/genética
18.
Comput Methods Programs Biomed ; 178: 237-246, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31416552

RESUMO

BACKGROUND AND OBJECTIVE: Retinal fundus images are widely used to diagnose retinal diseases and can potentially be used for early diagnosis and prevention of chronic vascular diseases and diabetes. While various automatic retinal vessel segmentation methods using deep learning have been proposed, they are mostly based on common CNN structures developed for other tasks such as classification. METHODS: We present a novel and simple multi-scale convolutional neural network (CNN) structure for retinal vessel segmentation. We first provide a theoretical analysis of existing multi-scale structures based on signal processing. In previous structures, multi-scale representations are achieved through downsampling by subsampling and decimation. By incorporating scale-space theory, we propose a simple yet effective multi-scale structure for CNNs using upsampling, which we term scale-space approximated CNN (SSANet). Based on further analysis of the effects of the SSA structure within a CNN, we also incorporate residual blocks, resulting in a multi-scale CNN that outperforms current state-of-the-art methods. RESULTS: Quantitative evaluations are presented as the area-under-curve (AUC) of the receiver operating characteristic (ROC) curve and the precision-recall curve, as well as accuracy, for four publicly available datasets, namely DRIVE, STARE, CHASE_DB1, and HRF. For the CHASE_DB1 set, the SSANet achieves state-of-the-art AUC value of 0.9916 for the ROC curve. An ablative analysis is presented to analyze the contribution of different components of the SSANet to the performance improvement. CONCLUSIONS: The proposed retinal SSANet achieves state-of-the-art or comparable accuracy across publicly available datasets, especially improving segmentation for thin vessels, vessel junctions, and central vessel reflexes.


Assuntos
Doenças Retinianas/diagnóstico por imagem , Vasos Retinianos/diagnóstico por imagem , Algoritmos , Área Sob a Curva , Aprendizado Profundo , Reações Falso-Positivas , Fundo de Olho , Humanos , Processamento de Imagem Assistida por Computador , Distribuição Normal , Curva ROC , Processamento de Sinais Assistido por Computador
19.
BMC Ophthalmol ; 19(1): 186, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31419954

RESUMO

BACKGROUND: This study aims to investigate the choroidal thickness and choroidal vascular density parameters and their correlation with severity of diabetic retinopathy (DR) in diabetes mellitus (DM) patients. METHODS: An observational cross-sectional study was conducted of 104 eyes, which were divided into 4 groups: Healthy controls (n = 38), DM with no DR eyes (n = 22), panretinal photocoagulation-untreated non-proliferative DR eyes (PRP-untreated NPDR eyes) (n = 24), PRP-untreated proliferative DR eyes (PRP-untreated PDR eyes) (n = 20). Optical coherence tomography (OCT) was performed. The total choroidal area (TCA), stromal area (SA), the luminal areas (LA) and the ratio of the luminal to choroidal area (L/C ratio) were compared. The choroidal parameters were also compared between PRP untreated and PRP-treated DR eyes. RESULTS: The L/C ratio values were 0.68 ± 0.06 in controls and 0.63 ± 0.04 in DM eyes (P < 0.001). But there were no statistically significant differences in retinal nerve fiber layer (RNFL) thickness, retinal thickness and subfoveal choroidal thickness (SCT) measurements between the two groups (P = 0.407, P = 0.654 and P = 0.849; respectively). The vessel density values were significantly different in DM with no DR eyes, PRP-untreated NPDR eyes and PRP-untreated PDR eyes (P < 0.001 for SCT, TCA and SA). The L/C ratio values in the three groups were significant different (P = 0.019). There was no significant difference in SCT, TCA, LA, SA and the L/C ratio between PRP-untreated and PRP-treated DR eyes. CONCLUSION: Eyes of patients with DM showed the L/C ratio decreased compared with normal controls. The SCT increased, but L/C ratio significantly decreased with severity of DR eyes compared with DM and normal eyes. Changes in the L/C ratio may predict DR development before they are otherwise evident clinically. Choroidal blood flow deficit can be an early pathologic change in DR.


Assuntos
Corioide/patologia , Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/diagnóstico , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Capilares/patologia , Corioide/irrigação sanguínea , Estudos Transversais , Retinopatia Diabética/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vasos Retinianos/diagnóstico por imagem , Estudos Retrospectivos , Índice de Gravidade de Doença
20.
Ophthalmic Surg Lasers Imaging Retina ; 50(8): 492-496, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31415695

RESUMO

BACKGROUND AND OBJECTIVE: To determine if a correlation exists between hyperautofluorescent ring size with visual acuity (VA), foveal avascular zone (FAZ) size, and retinal capillary perfusion density (CPD) in retinitis pigmentosa (RP). PATIENTS AND METHODS: Eighteen eyes from nine patients with RP were imaged using fundus autofluorescence (AF) to identify autofluorescence defects, and hyperautofluorescent ring size was measured with an image-processing program. Spectral-domain optical coherence tomography angiography was used to measure FAZ area and calculate parafoveal CPD in the superficial capillary plexus (SCP) and the deep capillary plexus (DCP) using both a 3 mm × 3 mm and 6 mm × 6 mm strategy. RESULTS: The area of hyperautofluorescence was not strongly correlated with SCP perfusion density (P = .74), DCP perfusion density (P = .25), FAZ area (P = .14), or VA (P = .33). CONCLUSION: The area of the hyperautofluorescent ring does not correlate with VA, retinal CPD, or FAZ area. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:492-496.].


Assuntos
Técnicas de Diagnóstico Oftalmológico , Macula Lutea/irrigação sanguínea , Imagem Multimodal/métodos , Vasos Retinianos/diagnóstico por imagem , Retinite Pigmentosa/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Angiofluoresceinografia/métodos , Fóvea Central/irrigação sanguínea , Humanos , Masculino , Pessoa de Meia-Idade , Retinite Pigmentosa/diagnóstico por imagem , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Acuidade Visual/fisiologia
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