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1.
Diagnostics (Basel) ; 14(15)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39125544

RESUMEN

Artificial intelligence has transformed medical diagnostic capabilities, particularly through medical image analysis. AI algorithms perform well in detecting abnormalities with a strong performance, enabling computer-aided diagnosis by analyzing the extensive amounts of patient data. The data serve as a foundation upon which algorithms learn and make predictions. Thus, the importance of data cannot be underestimated, and clinically corresponding datasets are required. Many researchers face a lack of medical data due to limited access, privacy concerns, or the absence of available annotations. One of the most widely used diagnostic tools in ophthalmology is Optical Coherence Tomography (OCT). Addressing the data availability issue is crucial for enhancing AI applications in the field of OCT diagnostics. This review aims to provide a comprehensive analysis of all publicly accessible retinal OCT datasets. Our main objective is to compile a list of OCT datasets and their properties, which can serve as an accessible reference, facilitating data curation for medical image analysis tasks. For this review, we searched through the Zenodo repository, Mendeley Data repository, MEDLINE database, and Google Dataset search engine. We systematically evaluated all the identified datasets and found 23 open-access datasets containing OCT images, which significantly vary in terms of size, scope, and ground-truth labels. Our findings indicate the need for improvement in data-sharing practices and standardized documentation. Enhancing the availability and quality of OCT datasets will support the development of AI algorithms and ultimately improve diagnostic capabilities in ophthalmology. By providing a comprehensive list of accessible OCT datasets, this review aims to facilitate better utilization and development of AI in medical image analysis.

2.
J Clin Med ; 13(13)2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38999540

RESUMEN

Background: This pilot study aimed to evaluate the Retinal Function Imager (RFI) for visualizing retinal vasculature and assessment of blood flow characteristics in patients with retinal vasculitis. The RFI is a non-invasive imaging device measuring the blood flow velocity (BFV) in secondary and tertiary retinal vessels using hemoglobin as an intrinsic motion-contrast agent. Methods: To test the feasibility of the RFI for patients with retinal vasculitis, capillary perfusion maps (nCPMs) were generated from 15 eyes of eight patients (five females; mean age: 49 ± 12 years) with a mean uveitis duration of 74 ± 85 months. Five of these patients had birdshot chorioretinopathy, and three had primarily non-occlusive venous retinal vasculitis of unknown origin. To reflect that the BFV may be more reduced in patients with prolonged disease, patients were classified into a short-term (uveitis duration: 8-15 months) and a long-term uveitis group (uveitis duration: 60-264 months). Data were compared with healthy controls (16 eyes of 11 patients; mean age 45 ± 12 years; 8 females). Results: The mean BFV in the controls was 3.79 ± 0.50 mm/s in the retinal arteries and 2.35 ± 0.44 mm/s in the retinal veins, which was significantly higher compared to the retinal vasculitis group. Patients revealed an arterial BFV of 2.75 ± 0.74 mm/s (p < 0.001) and a venous BFV of 1.75 ± 0.51 mm/s (p = 0.016). In the short-term group, a trend towards a decreased venular and arteriolar BFV was seen, while a significant reduction was observed in the long-term group. The patients' microvasculature anatomy revealed by the nCPMs appeared unevenly distributed and a lower number of blood vessels were seen, along with a lower degree of complexity of their branching patterns, when compared with controls. Conclusions: This study demonstrated a reduction in venular and arteriolar BFVs in patients with retinal vasculitis. BFV alterations were already observed in early disease stages and became more pronounced in progressed disease. Additionally, we showed that retinal microvasculature changes may be observed by nCPMs. Retinal imaging with the RFI may serve as a diagnostic and quantifying tool in retinal vasculitis.

3.
J Clin Med ; 13(1)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38202288

RESUMEN

This comprehensive review explores the role of Functional Near-Infrared Spectroscopy (fNIRS) in advancing our understanding of the visual system. Beginning with an introduction to fNIRS, we delve into its historical development, highlighting how this technology has evolved over time. The core of the review critically examines the advantages and disadvantages of fNIRS, offering a balanced view of its capabilities and limitations in research and clinical settings. We extend our discussion to the diverse applications of fNIRS beyond its traditional use, emphasizing its versatility across various fields. In the context of the visual system, this review provides an in-depth analysis of how fNIRS contributes to our understanding of eye function, including eye diseases. We discuss the intricacies of the visual cortex, how it responds to visual stimuli and the implications of these findings in both health and disease. A unique aspect of this review is the exploration of the intersection between fNIRS, virtual reality (VR), augmented reality (AR) and artificial intelligence (AI). We discuss how these cutting-edge technologies are synergizing with fNIRS to open new frontiers in visual system research. The review concludes with a forward-looking perspective, envisioning the future of fNIRS in a rapidly evolving technological landscape and its potential to revolutionize our approach to studying and understanding the visual system.

4.
J Alzheimers Dis ; 92(4): 1257-1267, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36872780

RESUMEN

BACKGROUND: Visual impairment could worsen sleep/wake disorders and cognitive decline. OBJECTIVE: To examine interrelations among self-reported visual impairment, sleep, and cognitive decline in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) Miami-site. METHOD: HCHS/SOL Miami-site participants ages 45-74 years (n = 665) at Visit-1, who returned for cognitive test 7-years later (SOL-INCA). Participants completed the National Eye Institute Visual Functioning Questionnaire (NEI-VFQ), validated sleep questionnaires and test for obstructive sleep apnea (OSA) at Visit-1. We obtained verbal episodic learning and memory, verbal fluency, processing speed, and executive functioning at Visit-1 and at SOL-INCA. Processing speed/executive functioning were added to SOL-INCA. We examined global cognition and change using a regression-based reliable change index, adjusting for the time lapse between Visit-1 and SOL-INCA. We used regression models to test whether 1) persons with OSA, self-reported sleep duration, insomnia, and sleepiness have an increased risk for visual impairment, 2a) visual impairment is associated with worse cognitive function and/or decline, and 2b) sleep disorders attenuate these associations. RESULT: Sleepiness (ß= 0.04; p < 0.01) and insomnia (ß= 0.04; p < 0.001) were cross-sectionally associated with visual impairment, adjusting for sociodemographic characteristics, behavioral factors, acculturation, and health conditions. Visual impairment was associated with lower global cognitive function at Visit-1 (ß= -0.16; p < 0.001) and on average 7-years later (ß= -0.18; p < 0.001). Visual impairment was also associated with a change in verbal fluency (ß= -0.17; p < 0.01). OSA, self-reported sleep duration, insomnia, and sleepiness did not attenuate any of the associations. CONCLUSION: Self-reported visual impairment was independently associated with worse cognitive function and decline.


Asunto(s)
Disfunción Cognitiva , Hispánicos o Latinos , Apnea Obstructiva del Sueño , Trastornos del Inicio y del Mantenimiento del Sueño , Trastornos de la Visión , Anciano , Humanos , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etnología , Disfunción Cognitiva/etiología , Disfunción Cognitiva/psicología , Hispánicos o Latinos/psicología , Autoinforme , Sueño , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/etnología , Apnea Obstructiva del Sueño/psicología , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones , Trastornos del Inicio y del Mantenimiento del Sueño/diagnóstico , Trastornos del Inicio y del Mantenimiento del Sueño/etnología , Trastornos del Inicio y del Mantenimiento del Sueño/psicología , Somnolencia , Trastornos de la Visión/complicaciones , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/etnología , Trastornos de la Visión/psicología , Persona de Mediana Edad , Duración del Sueño , Trastornos del Habla/diagnóstico , Trastornos del Habla/etnología , Trastornos del Habla/etiología , Trastornos del Habla/psicología
6.
J Aging Phys Act ; 31(3): 497-505, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36640780

RESUMEN

Regular physical exercise is known to lower the incidence of age-related eye diseases. We aimed to assess the acute chorioretinal alterations in older adults following intense physical strain. Seventeen senior elite athletes were recruited who underwent an aerobic exercise on a cycle ergometer and macular scanning by optical coherence tomography. A significant thinning of the entire retina was observed 1 min after exercise, followed by a thickening at 5 min, after which the thickness returned to baseline. This trend was similar in almost every single retinal layer, although a significant change was observed only in the inner retina. Choroidal thickness changes were neither significant nor did they correlate with the thickness changes of intraretinal layers. The mechanism of how these immediate retinal changes chronically impact age-related sight-threatening pathologies that, in turn, result in a substantially reduced quality of life warrants further investigation on nontrained older adults as well.


Asunto(s)
Calidad de Vida , Retina , Humanos , Anciano , Retina/diagnóstico por imagen , Retina/patología , Coroides/diagnóstico por imagen , Coroides/patología , Ejercicio Físico , Tomografía de Coherencia Óptica/métodos
7.
BMC Ophthalmol ; 22(1): 469, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36471292

RESUMEN

BACKGROUND: The study aimed to evaluate the changes in retinal vascular density in exudative age-related macular degeneration (AMD) after long-term anti-VEGF treatment using optical coherence tomography angiography (OCT-A), and to compare these changes with the vascular density in AMD treated for one year and healthy eyes. METHODS: In our cross-sectional study OCT-A was performed on 60 eyes of 60 patients. Group AMD 20 × consisted of patients receiving long-term (minimum 20 injections) aflibercept therapy (n = 17), and Group AMD one year consisted of patients treated for one year with a treat & extend protocol (n = 25). The vascular density values obtained with OCT-A were compared with an age-matched control group of 18 healthy eyes. We examined the central retinal thickness (CRT), the vascular density of the fovea and parafovea in the superficial and deep retinal plexus, and evaluated the extent of the non-flow area and the foveal avascular zone (FAZ) on a 3 × 3 mm macular region. Kruskal-Wallis test was performed for statistical analysis. RESULTS: In Group AMD 20x, the vascular density of superficial retinal plexus in the fovea (p = 0.0022) and parafovea (p < 0.0001) was significantly lower compared to Group one year and control group. In the deep retinal plexus, vascular density in the fovea (p = 0.0033) was significantly lower in both AMD groups compared to the control group, with no difference in the parafoveal region (p = 0.0774). The extent of non-flow area (p = 0.0003) and FAZ (p = 0.0008) were significantly larger in both AMD groups compared to the control group. There was a significant difference in CRT between those treated for one year and control eyes (p = 0.0036). CONCLUSIONS: In our study, we demonstrated that macular vessel density was lower in the foveal area in the superficial retinal plexus in AMD patients after one year and long-term anti-VEGF treatment. These vascular density changes were absent in the parafoveal and whole areas of the deep retinal plexus. Our results indicate that long-term anti-VEGF treatment reduces the vascular density of the superficial retinal plexus to a greater extent compared to the deep retinal plexus.


Asunto(s)
Degeneración Macular , Vasos Retinianos , Humanos , Angiografía con Fluoresceína/métodos , Estudios Transversales , Vasos Retinianos/patología , Tomografía de Coherencia Óptica/métodos , Inhibidores de la Angiogénesis , Inyecciones Intravítreas , Degeneración Macular/patología , Atrofia/patología , Estudios Retrospectivos
8.
PLoS One ; 17(5): e0268770, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35613112

RESUMEN

PURPOSE: There is abundant evidence on the benefits of physical activity on cardiovascular health. However, there are only few data on the acute effects of physical exercise on the retina and choroid. Our aim was the in vivo examination of chorioretinal alterations following short intense physical activity by spectral domain optical coherence tomography (SD-OCT). METHODS: Twenty-one eyes of 21 healthy, young subjects (mean age 22.5 ± 4.1 years, 15 males and 6 females) were recruited. Macular scanning with a SD-OCT was performed before and following a vita maxima-type physical strain exercise on a rowing ergometer until complete fatigue. Follow-up OCT scans were performed 1, 5, 15, 30 and 60 minutes following the exercise. The OCT images were exported and analyzed using our custom-built OCTRIMA 3D software and the thickness of 7 retinal layers was calculated, along with semi-automated measurement of the choroidal thickness. One-way ANOVA analysis was performed followed by Dunnett post hoc test for the thickness change compared to baseline and the correlation between performance and thickness change has also been calculated. The level of significance was set at 0.001. RESULTS: We observed a significant thinning of the total retina 1 minute post-exercise (-7.3 ± 0.6 µm, p < 0.001) which was followed by a significant thickening by 5 and 15 minutes (+3.6 ± 0.6 µm and +4.0 ± 0.6 µm, respectively, both p <0.001). Post-exercise retinal thickness returned to baseline by 30 minutes. This trend was present throughout the most layers of the retina, with significant changes in the ganglion cell-inner plexiform layer complex, (-1.3 ± 0.1 µm, +0.6 ± 0.1 µm and +0.7 ± 0.1 µm, respectively, p <0.001 for all), in the inner nuclear layer at 1 and 5 minutes (-0.8 ± 0.1 µm and +0.8 ± 0.1 µm, respectively, p <0.001 for both), in the outer nuclear layer-photoreceptor inner segment complex at 5 minute (+2.3 ± 0.4 µm, p <0.001 for all) and in the interdigitation zone-retinal pigment epithelium complex at 1 and 15 minutes (-3.3 ± 0.4 µm and +1.8 ± 0.4 µm, respectively, p <0.001 for both). There was no significant change in choroidal thickness; however, we could detect a tendency towards thinning at 1, 15, and 30 minutes following exercise. The observed changes in thickness change did not correlate with performance. Similar trends were observed in both professional and amateur sportsmen (n = 15 and n = 6, respectively). The absolute changes in choroidal thickness did not show any correlation with the thickness changes of the intraretinal layers. CONCLUSIONS: Our study implies that in young adults, intense physical exercise has an acute effect on the granular layers of the retina, resulting in thinning followed by rebound thickening before normalization. We could not identify any clear correlation with either choroidal changes or performance that might explain our observations, and hence the exact mechanism warrants further clarification. We believe that a combination of vascular and mechanic changes is behind the observed trends.


Asunto(s)
Coroides , Tomografía de Coherencia Óptica , Adolescente , Adulto , Coroides/irrigación sanguínea , Coroides/diagnóstico por imagen , Ejercicio Físico , Femenino , Humanos , Masculino , Retina/diagnóstico por imagen , Epitelio Pigmentado de la Retina , Tomografía de Coherencia Óptica/métodos , Adulto Joven
9.
Neurology ; 97(2): 68-79, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-33910937

RESUMEN

OBJECTIVE: To update the consensus recommendations for reporting of quantitative optical coherence tomography (OCT) study results, thus revising the previously published Advised Protocol for OCT Study Terminology and Elements (APOSTEL) recommendations. METHODS: To identify studies reporting quantitative OCT results, we performed a PubMed search for the terms "quantitative" and "optical coherence tomography" from 2015 to 2017. Corresponding authors of the identified publications were invited to provide feedback on the initial APOSTEL recommendations via online surveys following the principle of a modified Delphi method. The results were evaluated and discussed by a panel of experts and changes to the initial recommendations were proposed. A final survey was recirculated among the corresponding authors to obtain a majority vote on the proposed changes. RESULTS: A total of 116 authors participated in the surveys, resulting in 15 suggestions, of which 12 were finally accepted and incorporated into an updated 9-point checklist. We harmonized the nomenclature of the outer retinal layers, added the exact area of measurement to the description of volume scans, and suggested reporting device-specific features. We advised to address potential bias in manual segmentation or manual correction of segmentation errors. References to specific reporting guidelines and room light conditions were removed. The participants' consensus with the recommendations increased from 80% for the previous APOSTEL version to greater than 90%. CONCLUSIONS: The modified Delphi method resulted in an expert-led guideline (evidence Class III; Grading of Recommendations, Assessment, Development and Evaluations [GRADE] criteria) concerning study protocol, acquisition device, acquisition settings, scanning protocol, funduscopic imaging, postacquisition data selection, postacquisition analysis, nomenclature and abbreviations, and statistical approach. It will be essential to update these recommendations to new research and practices regularly.


Asunto(s)
Proyectos de Investigación , Enfermedades de la Retina/diagnóstico por imagen , Tomografía de Coherencia Óptica , Consenso , Técnica Delphi , Humanos , Oftalmología/métodos
10.
Expert Rev Med Devices ; 18(3): 225-237, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33635742

RESUMEN

INTRODUCTION: Ocular blood flow plays a critical role in eye health by nourishing the retinal and ocular tissues with oxygen and nutrients and removal of ocular metabolic waste. Imaging of retinal and optic blood flow may provide insights for early and more specific diagnoses of ocular vascular disorder and facilitate eye-based biomarkers applicable to neurological health assessment and research. AREAS COVERED: The ability of the XyCAM RI (Vasoptic Medical Inc., MD, USA) to visualize and to analyze ocular blood flow dynamics XyCAM RI using laser speckle contrast imaging is reviewed and compared with concurrent clinical ophthalmic imaging technologies like optical coherence tomography - angiography (OCT-A), fundus imaging, fluorescein angiography (FA), indocyanine green angiography (ICGA), laser Doppler flowmetry (LDF), and laser speckle flowgraphy (LSFG). EXPERT OPINION: XyCAM RI, with its unprecedented imaging capabilities to assess blood flow dynamics provides a powerful tool to ophthalmic researchers and doctors to obtain greater clinical insights into the physiological status of the posterior segment and treatment approaches for various diseases in a very patient-friendly, noninvasive manner, unlike dye-based angiographic techniques such as FA or ICG. XyCAM RI is well suited as a modality that could close the gap between current screening and comprehensive eye exams.


Asunto(s)
Flujo Sanguíneo Regional/fisiología , Vasos Retinianos/diagnóstico por imagen , Vasos Retinianos/fisiología , Ensayos Clínicos como Asunto , Estudios de Factibilidad , Humanos , Reproducibilidad de los Resultados , Enfermedades de la Retina/diagnóstico , Enfermedades de la Retina/diagnóstico por imagen
11.
Int J Ophthalmol ; 14(1): 57-63, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33469484

RESUMEN

AIM: To evaluate a high-resolution functional imaging device that yields quantitative data regarding macular blood flow and capillary network features in eyes with diabetic retinopathy (DR). METHODS: Prospective, cross-sectional comparative case-series in which blood flow velocities (BFVs) and non-invasive capillary perfusion maps (nCPMs) in macular vessels were measured in patients with DR and in healthy controls using the Retinal Functional Imager (RFI) device. RESULTS: A total of 27 eyes of 21 subjects were studied [9 eyes nonproliferative diabetic retinopathy (NPDR), 9 eyes proliferative diabetic retinopathy (PDR) and 9 controls]. All diabetic patients were type 2. All patients with NPDR and 5 eyes with PDR also had diabetic macular edema (DME). The NPDR group included eyes with severe (n=3) and moderate NPDR (n=6), and were symptomatic. A significant decrease in venular BFVs was observed in the macular region of PDR eyes when compared to controls (2.61±0.6 mm/s and 2.92±0.72 mm/s in PDR and controls, respectively, P=0.019) as well as PDR eyes with DME compared to NPDR eyes (2.36±0.51 mm/s and 2.94±1.09 mm/s in PDR with DME and NPDR, respectively, P=0.01). CONCLUSION: The RFI, a non-invasive imaging tool, provides high-resolution functional imaging of the retinal microvasculature and quantitative measurement of BFVs in visually impaired DR patients. The isolated diminish venular BFVs in PDR eyes compared to healthy eyes and PDR eyes with DME in comparison to NPDR eyes may indicate the possibility of more retinal vein compromise than suspected in advanced DR.

12.
Alzheimers Dement ; 17(1): 103-111, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33090722

RESUMEN

In the last 20 years, research focused on developing retinal imaging as a source of potential biomarkers for Alzheimer's disease and other neurodegenerative diseases, has increased significantly. The Alzheimer's Association and the Alzheimer's & Dementia: Diagnosis, Assessment, Disease Monitoring editorial team (companion journal to Alzheimer's & Dementia) convened an interdisciplinary discussion in 2019 to identify a path to expedite the development of retinal biomarkers capable of identifying biological changes associated with AD, and for tracking progression of disease severity over time. As different retinal imaging modalities provide different types of structural and/or functional information, the discussion reflected on these modalities and their respective strengths and weaknesses. Discussion further focused on the importance of defining the context of use to help guide the development of retinal biomarkers. Moving from research to context of use, and ultimately to clinical evaluation, this article outlines ongoing retinal imaging research today in Alzheimer's and other brain diseases, including a discussion of future directions for this area of study.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedades Neurodegenerativas/diagnóstico por imagen , Retina/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Biomarcadores , Encéfalo/diagnóstico por imagen , Humanos , Persona de Mediana Edad
13.
Alzheimers Dement (Amst) ; 12(1): e12119, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33163610

RESUMEN

INTRODUCTION: We propose a minimum data set framework for the acquisition and analysis of retinal images for the development of retinal Alzheimer's disease (AD) biomarkers. Our goal is to describe methodology that will increase concordance across laboratories, so that the broader research community is able to cross-validate findings in parallel, accumulate large databases with normative data across the cognitive aging spectrum, and progress the application of this technology from the discovery stage to the validation stage in the search for sensitive and specific retinal biomarkers in AD. METHODS: The proposed minimum data set framework is based on the Atlas of Retinal Imaging Study (ARIAS), an ongoing, longitudinal, multi-site observational cohort study. However, the ARIAS protocol has been edited and refined with the expertise of all co-authors, representing 16 institutions, and research groups from three countries, as a first step to address a pressing need identified by experts in neuroscience, neurology, optometry, and ophthalmology at the Retinal Imaging in Alzheimer's Disease (RIAD) conference, convened by the Alzheimer's Association and held in Washington, DC, in May 2019. RESULTS: Our framework delineates specific imaging protocols and methods of analysis for imaging structural changes in retinal neuronal layers, with optional add-on procedures of fundus autofluorescence to examine beta-amyloid accumulation and optical coherence tomography angiography to examine AD-related changes in the retinal vasculature. DISCUSSION: This minimum data set represents a first step toward the standardization of retinal imaging data acquisition and analysis in cognitive aging and AD. A standardized approach is essential to move from discovery to validation, and to examine which retinal AD biomarkers may be more sensitive and specific for the different stages of the disease severity spectrum. This approach has worked for other biomarkers in the AD field, such as magnetic resonance imaging; amyloid positron emission tomography; and, more recently, blood proteomics. Potential context of use for retinal AD biomarkers is discussed.

14.
Nepal J Ophthalmol ; 12(23): 1-3, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32799232
15.
Alzheimers Dement ; 16(1): 229-243, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31914225

RESUMEN

The last decade has seen a substantial increase in research focused on the identification, development, and validation of diagnostic and prognostic retinal biomarkers for Alzheimer's disease (AD). Sensitive retinal biomarkers may be advantageous because they are cost and time efficient, non-invasive, and present a minimal degree of patient risk and a high degree of accessibility. Much of the work in this area thus far has focused on distinguishing between symptomatic AD and/or mild cognitive impairment (MCI) and cognitively normal older adults. Minimal work has been done on the detection of preclinical AD, the earliest stage of AD pathogenesis characterized by the accumulation of cerebral amyloid absent clinical symptoms of MCI or dementia. The following review examines retinal structural changes, proteinopathies, and vascular alterations that have been proposed as potential AD biomarkers, with a focus on studies examining the earliest stages of disease pathogenesis. In addition, we present recommendations for future research to move beyond the discovery phase and toward validation of AD risk biomarkers that could potentially be used as a first step in a multistep screening process for AD risk detection.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Biomarcadores/análisis , Disfunción Cognitiva/diagnóstico por imagen , Conocimientos, Actitudes y Práctica en Salud , Tamizaje Masivo , Síntomas Prodrómicos , Enfermedad de Alzheimer/patología , Amiloide , Humanos , Tomografía de Coherencia Óptica
16.
Neurophotonics ; 6(4): 041109, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31572744

RESUMEN

The development of effective therapies for cognitive impairment (CI), especially due to Alzheimer's disease, demands diagnosing the condition during the prodromal phase. The diagnosis of CI involves expensive and invasive methods, such as positron emission tomography and cerebrospinal fluid assessment via spinal tap. Hence, a comparatively lower cost and noninvasive method of diagnosis is imperative. The human retina is an extension of the brain characterized by similarities in vascular and neural structures. The complications of CI are not only limited to the brain but also affect the retina for which the loss of retinal ganglion cells has been associated with neurodegeneration in the brain. The loss of retinal ganglion cells in individuals with CI may be related to reduced vascular demand and a potential remodeling of the retinal vascular branching complexity. Retinal imaging biomarkers may provide a low cost and noninvasive alternative for the diagnosis of CI. In this study, the retinal vascular branching complexity of patients with CI was characterized using the singularity spectrum multifractal dimension and lacunarity parameter. A reduced vascular branching complexity was observed in subjects with CI when compared to age- and sex-matched cognitively healthy controls. Significant associations were also found between retinal vascular and functional parameters.

17.
Ophthalmol Retina ; 3(4): 371-378, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-31014690

RESUMEN

PURPOSE: To compare thickness and reflectance of retinal layer findings in patients with idiopathic epiretinal membranes (ERMs) before and after surgery with those of normal controls. DESIGN: Retrospective study. PARTICIPANTS: Patients with ERMs before and after surgery and healthy controls. METHODS: Spectral-domain (SD) OCT imaging of eyes with ERMs before and after surgery and of healthy eyes were analyzed for morphologic appearance and using a customized algorithm to measure retinal layer reflectance and thickness. Findings were correlated with visual acuity outcomes. MAIN OUTCOME MEASURES: Retinal layer thickness and reflectance. RESULTS: Thirty-four ERM and 12 healthy eyes were identified. Mean preoperative best-corrected visual acuity (BCVA) improved from 0.53±0.31 logarithm of the minimum angle of resolution (logMAR; Snellen equivalent, 20/68) to 0.41±0.25 logMAR (Snellen equivalent, 20/51) after surgery (P = 0.030). Differences in reflectance and thickness of retinal layers were identified among the preoperative ERM, postoperative ERM, and healthy eyes. High preoperative reflectance of the internal limiting membrane (ILM) to outer plexiform layer (OPL) was correlated with better postoperative BCVA (r = -0.451; P = 0.007). A larger improvement in BCVA was correlated with preoperative thick measurements of the outer nuclear layer (r = 0.514; P = 0.002), high reflectance of the group of layers from the ILM to the OPL (r = 0.426; P = 0.012), and low reflectance of the photoreceptor layer (r = -0.453; P = 0.007). Using linear regression analysis, better postoperative BCVA was associated with better preoperative vision (standardized regression coefficient, 0.553; P = 0.001) and high reflectance of the group of layers from the ILM to OPL (standardized regression coefficient, -0.526; P = 0.001). A larger improvement in BCVA was associated with worse preoperative BCVA (standardized regression coefficient, -0.539; P < 0.001) and high reflectance of the group of layers from the ILM to OPL (standardized regression coefficient, -0.428; P = 0.001). CONCLUSIONS: Quantitative differences in reflectance and thickness among preoperative, postoperative, and normal SD OCT imaging allow assessment of retina layer changes secondary to ERMs. High reflectance of the ILM to OPL correlated with and was associated with better postoperative BCVA and improvement in BCVA.


Asunto(s)
Membrana Basal/cirugía , Membrana Epirretinal/cirugía , Retina/patología , Tomografía de Coherencia Óptica/métodos , Agudeza Visual , Vitrectomía/métodos , Anciano , Membrana Epirretinal/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Periodo Posoperatorio , Periodo Preoperatorio , Estudios Retrospectivos
18.
Klin Monbl Augenheilkd ; 235(4): 377-384, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29669366

RESUMEN

Diabetic retinopathy (DR) is one of the leading causes of vision loss globally with a severe burden on all societies due to its high treatment and rehabilitation costs. The early diagnosis of DR may provide preventive steps (including retinal laser therapy and tight carbohydrate, blood pressure, and cholesterol control) that could in turn help to avoid progression of the pathology with the resultant vision loss. Optical coherence tomography (OCT) enables the in vivo structural imaging of the retina, providing both qualitative (structure) and quantitative (thickness) information. In the past decades, extensive OCT research has been done in the field of DR. In the present review, we are focusing on those that were aiming at detection of the earliest retinal changes before DR could be diagnosed funduscopically. The latest, widely available technology of spectral-domain (SD-)OCT comes with a fast and reliable retinal imaging, which, together with the most recent developments in image processing and artificial intelligence, holds the promise of developing a quick and efficient, state-of-the-art screening tool for DR.


Asunto(s)
Retinopatía Diabética/diagnóstico , Diagnóstico Precoz , Tomografía de Coherencia Óptica , Terapia Combinada , Aprendizaje Profundo , Retinopatía Diabética/terapia , Intervención Médica Temprana , Humanos , Interpretación de Imagen Asistida por Computador , Tamizaje Masivo , Oftalmoscopios
19.
Ophthalmic Surg Lasers Imaging Retina ; 48(10): 799-809, 2017 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29020423

RESUMEN

BACKGROUND AND OBJECTIVES: Several imaging modalities have been developed to characterize ischemia inherent in retinal vascular diseases. This study aims to predict the impact and to better establish the mechanisms of visual deterioration. A high-resolution functional imaging device is used, yielding quantitative data for macular blood flow and capillary network features in healthy eyes and in eyes with central retinal vein occlusion (CRVO) or branch retinal vein occlusion (BRVO). PATIENTS AND METHODS: This prospective, cross-sectional, comparative case series measured blood flow velocities (BFVs) and noninvasive capillary perfusion maps (nCPMs) in macular vessels in patients with BRVO/CRVO and in healthy controls using the Retinal Function Imager (RFI; Optical Imaging, Rehovot, Israel). RESULTS: Twenty-two eyes of 21 subjects were studied (eight with CRVO, five with BRVO, and nine controls). A significant decrease was observed in the BFVs of both arterioles and venules in the affected macular region of patients with CRVO and BRVO (2.84 ± 1.21 mm/s and 2.67 ± 1.43 mm/s in CRVO/BRVO arterioles, respectively, vs. 4.23 ± 1.04 mm/s in healthy controls, P < .001; and 1.64 ± 0.51 mm/s and 1.60 ± 0.41 mm/s in CRVO/BRVO venules, respectively, vs. 2.88 ± 0.93 mm/s in healthy controls, P < .001). BFVs in non-affected macular regions of patients with BRVO were not statistically different from BFVs in healthy eyes (3.84 ± 1.04 mm/s and 3.17 ± 1.39 mm/s in BRVO patients vs. 4.23 ± 1.04 mm/s and 2.88 ± 0.93 mm/s in healthy controls' arterioles and venules, respectively; P ≥ .1). nCPMs allowed high-resolution imaging of the macular vasculature and successfully demonstrated ischemic areas in the RVO groups. CONCLUSIONS: The RFI provided high-resolution functional imaging of the retinal microvasculature and enabled quantitative measurement of BFVs in patients with RVO. Diminished flow velocity in arterioles and venules raises the possibility that RVO represents a panvascular compromise not confined to just venous stasis or its secondary arteriolar effects. The RFI offers potential to help with diagnosis and management of RVO cases. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:799-809.].


Asunto(s)
Mácula Lútea/diagnóstico por imagen , Oclusión de la Vena Retiniana/diagnóstico por imagen , Vasos Retinianos/diagnóstico por imagen , Inhibidores de la Angiogénesis/uso terapéutico , Bevacizumab/uso terapéutico , Capilares/diagnóstico por imagen , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Flujo Sanguíneo Regional/fisiología , Hemorragia Retiniana/diagnóstico por imagen , Oclusión de la Vena Retiniana/tratamiento farmacológico
20.
Curr Diab Rep ; 16(12): 132, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27841014

RESUMEN

In the years since its introduction, retinal imaging has transformed our capability to visualize the posterior pole of the eye. Increasing practical advances in mobile technology, regular monitoring, and population screening for diabetic retinopathy management offer the opportunity for further development of cost-effective applications through remote assessment of the diabetic eye using portable retinal cameras, smart-phone-based devices and telemedicine networks. Numerous retinal imaging methods and mobile technologies in tele-ophthalmology applications have been reported for diabetic retinopathy screening and management. They provide several advantages of automation, sensitivity, specificity, portability, and miniaturization for the development of point-of-care diagnostics for eye complications in diabetes. The aim of this paper is to review the role of retinal imaging and mobile technologies in tele-ophthalmology applications for diabetic retinopathy screening and management. At large, although improvements in current technology and telemedicine services are still needed, telemedicine has demonstrated to be a worthy tool to support health caregivers in the effective management and prevention of diabetes and its complications.


Asunto(s)
Retinopatía Diabética/diagnóstico , Oftalmología/instrumentación , Retina/diagnóstico por imagen , Telemedicina/métodos , Análisis Costo-Beneficio , Retinopatía Diabética/terapia , Humanos , Oftalmoscopios , Sistemas de Atención de Punto
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