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Ophthalmology Nov 2019To investigate the relationship between the diabetic retinopathy (DR) severity and quantitative ultra-widefield angiographic metrics, including leakage index, ischemic...
PURPOSE
To investigate the relationship between the diabetic retinopathy (DR) severity and quantitative ultra-widefield angiographic metrics, including leakage index, ischemic index, and microaneurysm count.
DESIGN
Retrospective image analysis study.
METHODS
Eyes with DR that had undergone ultra-widefield fluorescein angiography (UWFA) with associated color photography were identified. All eyes were laser-naive and had not received any intravitreal pharmacotherapy within 6 months of UWFA. Each eye was graded for DR severity. Quantitative angiographic parameters were evaluated with a semiautomated analysis platform with expert reader correction, as needed. Angiographic parameters included panretinal leakage index, ischemic index, and microaneurysm count. Clinical characteristics analyzed included age, gender, race, hemoglobin A1C level, hypertension, systolic blood pressure, diastolic blood pressure, and smoking history.
MAIN OUTCOME MEASURES
Association of DR severity with panretinal leakage index, ischemic index, and microaneurysm count.
RESULTS
Three hundred thirty-nine eyes were included with mean age of 62±13 years. Forty-two percent of eyes were from women and 57.5% were from men. Distribution of DR severity was as follows: mild NPDR in 11.2%, moderate NPDR in 23.9%, severe NPDR in 40.1%, and PDR with 24.8%. Panretinal leakage index [mild NPDR (mean = 0.51%), moderate NPDR mean = 1.20%, severe NPDR (mean = 2.75%), and PDR (mean = 5.84%); P<2×10], panretinal ischemic index [mild NPDR (mean = 0.95%, moderate NPDR (mean = 1.37%), severe NPDR (mean = 2.80%), and PDR (mean = 9.53%); P<2×10], and panretinal microaneurysm count [mild NPDR (mean = 36), moderate NPDR (mean = 129), severe NPDR (mean = 203), and PDR (mean = 254); P<5×10] were strongly associated with DR severity. Multivariate analysis demonstrated that ischemic index and leakage index were the parameters associated most strongly with level of DR severity.
CONCLUSIONS
Panretinal leakage index, panretinal ischemic index, and panretinal microaneurysm count are associated with DR severity. Additional research is needed to understand the clinical implications of these parameters related to progression risk, prognosis, and implications for therapeutic response.
Topics: Adult; Aged; Blood Pressure; Capillary Permeability; Diabetic Retinopathy; Female; Fluorescein Angiography; Glycated Hemoglobin; Humans; Hypertension; Ischemia; Male; Microaneurysm; Middle Aged; Retinal Vessels; Retrospective Studies; Severity of Illness Index; Smoking; Visual Acuity
PubMed: 31383482
DOI: 10.1016/j.ophtha.2019.05.034 -
Journal of Clinical Medicine Jan 2021The technologies of ocular imaging modalities such as optical coherence tomography (OCT) and OCT angiography (OCTA) have progressed remarkably. Of these in vivo imaging... (Review)
Review
The technologies of ocular imaging modalities such as optical coherence tomography (OCT) and OCT angiography (OCTA) have progressed remarkably. Of these in vivo imaging modalities, recently advanced OCT technology provides high-resolution images, e.g., histologic imaging, enabling anatomical analysis of each retinal layer, including the photoreceptor layers. Recently developed OCTA also visualizes the vascular networks three-dimensionally, which provides better understanding of the retinal deep capillary layer. In addition, ex vivo analysis using autologous aqueous or vitreous humor shows that inflammatory cytokine levels including vascular endothelial growth factor (VEGF) are elevated and correlated with the severity of macular edema (ME) in eyes with retinal vein occlusion (RVO). Furthermore, a combination of multiple modalities enables deeper understanding of the pathology. Regarding therapy, intravitreal injection of anti-VEGF drugs provides rapid resolution of ME and much better visual improvements than conventional treatments in eyes with RVO. Thus, the technologies of examination and treatment for managing eyes with RVO have progressed rapidly. In this paper, we review the multimodal imaging and therapeutic strategies for eyes with RVO with the hope that it provides better understanding of the pathology and leads to the development of new therapies.
PubMed: 33494354
DOI: 10.3390/jcm10030405 -
Graefe's Archive For Clinical and... Nov 2022To investigate the relevance of microaneurysm morphology in optical coherence tomography angiography (OCTA) image averaging and fluorescein leakage in diabetic...
PURPOSE
To investigate the relevance of microaneurysm morphology in optical coherence tomography angiography (OCTA) image averaging and fluorescein leakage in diabetic retinopathy (DR).
METHODS
In 38 consecutive patients with DR, ten consecutive 3- × 3-mm fovea-centered OCTA (HS100, Canon Inc., Tokyo, Japan) and fluorescein angiography (FA) were performed, and averaged OCTA images were created based on the 10 images. After detecting all microaneurysms in FA images, the morphology was classified into four types (focal bulge, saccular/pedunculated, fusiform, and mixed) using averaged OCTA images. The correlation between microaneurysm leakage in FA, retinopathy stage, and microaneurysm morphology was estimated.
RESULTS
Thirty-eight eyes (50.0%) of the 33 patients were available for analysis, and 370 (63.5%) of the 583 FA-detected microaneurysms were morphologically classifiable (focal bulge, 46; saccular/pedunculated, 143; fusiform, 29; and mixed, 152) in OCTA. There was a significant correlation between stage and percentage of microaneurysm morphology and between morphology and the presence of leakage (P < 0.0001 and P < 0.01, respectively). The proportion of focal bulges decreased with stage progression, while the other three types increased with stage progression. The percentage of FA leakage for focal bulge, saccular/pedunculated, fusiform, and mixed was 41.3%, 66.4%, 82.8%, and 66.4%, respectively, and the fusiform type showed significant FA leakage.
CONCLUSION
Microaneurysm morphology is correlated with the DR stage and FA leakage. Microaneurysm morphology recognition using OCTA image averaging may be useful for the clinical evaluation of DR.
Topics: Humans; Diabetic Retinopathy; Microaneurysm; Tomography, Optical Coherence; Retinal Vessels; Visual Acuity; Fluorescein Angiography; Fovea Centralis; Fluoresceins; Diabetes Mellitus
PubMed: 35665851
DOI: 10.1007/s00417-022-05713-7 -
Biomedicine & Pharmacotherapy =... Nov 2018Diabetic Retinopathy (DR) is an outcome of prolonged diabetes which directly or indirectly affect the human vision. DR is asymptomatic in its early stages and the late... (Review)
Review
Diabetic Retinopathy (DR) is an outcome of prolonged diabetes which directly or indirectly affect the human vision. DR is asymptomatic in its early stages and the late diagnosis lead to undeviating loss of vision. The computer aided diagnosis with the assistance of medical images helps in timely and accurate treatment. Microaneurysms (MA) mark the onset of DR, thus a vital point in screening of this disease. This review discuses various state of the art methods available till date for automated computer aided analysis of microaneurysms and haemorrhages. The paper also highlights qualitative and quantitative comparison of the existing literature with limitations for analysis of microaneurysms and haemorrhages. It is an attempt to systematize the available algorithms for an easy gathering and guidance to researchers working in this domain for future research.
Topics: Algorithms; Deep Learning; Diabetic Retinopathy; Humans; Image Processing, Computer-Assisted; Microaneurysm
PubMed: 30130729
DOI: 10.1016/j.biopha.2018.07.175 -
Postgraduate Medicine Aug 2015Diabetic retinopathy is the leading cause of vision loss in working-age adults; it is a highly prevalent cause of vision loss overall and has a potent impact on the... (Review)
Review
INTRODUCTION
Diabetic retinopathy is the leading cause of vision loss in working-age adults; it is a highly prevalent cause of vision loss overall and has a potent impact on the quality of life in those with diabetes mellitus and public health in general. Diabetic macular edema (DME) is the most common cause of vision loss from diabetic retinopathy. In patients with diabetes mellitus, chronic hyperglycemia leads to activation of the inflammatory cascade and retinal capillary damage that result in microaneurysm formation in the retina. In addition to the possibility of associated ischemia, microaneurysms are hyperpermeable; the resultant loss of the blood-retinal barrier leads to vision loss if consequent edema involves the center of the fovea. The standard of DME therapy for >25 years was focal laser photocoagulation applied to or near the microaneurysms. However, results from clinical trials of intravitreal vascular endothelial growth factor (VEGF) blockers and corticosteroids for the treatment of DME have led to a dramatic paradigm shift away from laser therapy to primary treatment with these pharmacologic agents.
METHODS
Medline literature search of approaches for treating DME.
RESULTS
Intravitreal pharmacologic treatments with anti-VEGF agents and corticosteroids have recently been shown to be superior to laser treatment of DME.
CONCLUSION
The existence of pharmacologic treatment of DME, shown to be superior to laser monotherapy, has created a seismic change in the approach of treatment of these patients. This review provides a summary of the therapies and the rationale regarding the current pharmacologic therapy of DME.
Topics: Angiogenesis Inhibitors; Antibodies, Monoclonal, Humanized; Aptamers, Nucleotide; Bevacizumab; Diabetic Retinopathy; Glucocorticoids; Humans; Intravitreal Injections; Macular Edema; Ranibizumab
PubMed: 26036708
DOI: 10.1080/00325481.2015.1052523 -
Cureus Jul 2021Coats' disease is an idiopathic non-hereditary condition first described by Coats in 1908 as a congenital retinal telangiectatic and aneurysmal disease associated with...
Coats' disease is an idiopathic non-hereditary condition first described by Coats in 1908 as a congenital retinal telangiectatic and aneurysmal disease associated with retinal exudation. Its presentation is classically in early childhood. We report a rare case of Coats' disease that first presented during adulthood in a 35-year-old male. The patient presented with visual loss in the left eye for two months. His visual acuity was counting fingers in the left eye and fundus examination revealed extensive lipid exudation in the macula with telangiectatic vessels and microaneurysms with vascular malformation in the inferotemporal quadrant. Fluorescein angiography showed leakage from the telangiectatic vessels, and optic coherence tomography showed significant macular edema. A provisional diagnosis of adult-onset Coats' disease was made. The patient responded well to intravitreal ranibizumab injections for macular edema and sectoral argon laser photocoagulation for peripheral vascular abnormalities. This case is unusual in adulthood onset and the first presentation was during adulthood in the third decade of life in contrast to the typical age of onset which is younger than five years.
PubMed: 34381658
DOI: 10.7759/cureus.16303 -
Journal Francais D'ophtalmologie Mar 2021Diabetic retinopathy (DR) is a disease facilitated by the rapid spread of diabetes worldwide. DR can blind diabetic individuals. Early detection of DR is essential to... (Review)
Review
Diabetic retinopathy (DR) is a disease facilitated by the rapid spread of diabetes worldwide. DR can blind diabetic individuals. Early detection of DR is essential to restoring vision and providing timely treatment. DR can be detected manually by an ophthalmologist, examining the retinal and fundus images to analyze the macula, morphological changes in blood vessels, hemorrhage, exudates, and/or microaneurysms. This is a time consuming, costly, and challenging task. An automated system can easily perform this function by using artificial intelligence, especially in screening for early DR. Recently, much state-of-the-art research relevant to the identification of DR has been reported. This article describes the current methods of detecting non-proliferative diabetic retinopathy, exudates, hemorrhage, and microaneurysms. In addition, the authors point out future directions in overcoming current challenges in the field of DR research.
Topics: Artificial Intelligence; Diabetes Mellitus; Diabetic Retinopathy; Fundus Oculi; Humans; Microaneurysm; Retina
PubMed: 33526268
DOI: 10.1016/j.jfo.2020.08.009 -
Bioengineering (Basel, Switzerland) Dec 2023Diabetic retinopathy (DR) is a microvascular complication of diabetes. Microaneurysms (MAs) are often observed in the retinal vessels of diabetic patients and represent...
Diabetic retinopathy (DR) is a microvascular complication of diabetes. Microaneurysms (MAs) are often observed in the retinal vessels of diabetic patients and represent one of the earliest signs of DR. Accurate and efficient detection of MAs is crucial for the diagnosis of DR. In this study, an automatic model (MA-YOLO) is proposed for MA detection in fluorescein angiography (FFA) images. To obtain detailed features and improve the discriminability of MAs in FFA images, SwinIR was utilized to reconstruct super-resolution images. To solve the problems of missed detection of small features and feature information loss, an MA detection layer was added between the neck and the head sections of YOLOv8. To enhance the generalization ability of the MA-YOLO model, transfer learning was conducted between high-resolution images and low-resolution images. To avoid excessive penalization due to geometric factors and address sample distribution imbalance, the loss function was optimized by taking the Wise-IoU loss as a bounding box regression loss. The performance of the MA-YOLO model in MA detection was compared with that of other state-of-the-art models, including SSD, RetinaNet, YOLOv5, YOLOX, and YOLOv7. The results showed that the MA-YOLO model had the best performance in MA detection, as shown by its optimal metrics, including recall, precision, F1 score, and AP, which were 88.23%, 97.98%, 92.85%, and 94.62%, respectively. Collectively, the proposed MA-YOLO model is suitable for the automatic detection of MAs in FFA images, which can assist ophthalmologists in the diagnosis of the progression of DR.
PubMed: 38135996
DOI: 10.3390/bioengineering10121405 -
Proceedings of the National Academy of... Mar 2021Understanding the mechanics of blood flow is necessary for developing insights into mechanisms of physiology and vascular diseases in microcirculation. Given the...
Understanding the mechanics of blood flow is necessary for developing insights into mechanisms of physiology and vascular diseases in microcirculation. Given the limitations of technologies available for assessing in vivo flow fields, in vitro methods based on traditional microfluidic platforms have been developed to mimic physiological conditions. However, existing methods lack the capability to provide accurate assessment of these flow fields, particularly in vessels with complex geometries. Conventional approaches to quantify flow fields rely either on analyzing only visual images or on enforcing underlying physics without considering visualization data, which could compromise accuracy of predictions. Here, we present artificial-intelligence velocimetry (AIV) to quantify velocity and stress fields of blood flow by integrating the imaging data with underlying physics using physics-informed neural networks. We demonstrate the capability of AIV by quantifying hemodynamics in microchannels designed to mimic saccular-shaped microaneurysms (microaneurysm-on-a-chip, or MAOAC), which signify common manifestations of diabetic retinopathy, a leading cause of vision loss from blood-vessel damage in the retina in diabetic patients. We show that AIV can, without any a priori knowledge of the inlet and outlet boundary conditions, infer the two-dimensional (2D) flow fields from a sequence of 2D images of blood flow in MAOAC, but also can infer three-dimensional (3D) flow fields using only 2D images, thanks to the encoded physics laws. AIV provides a unique paradigm that seamlessly integrates images, experimental data, and underlying physics using neural networks to automatically analyze experimental data and infer key hemodynamic indicators that assess vascular injury.
Topics: Artificial Intelligence; Blood Flow Velocity; Computer Simulation; Diabetic Retinopathy; Hemodynamics; Humans; Imaging, Three-Dimensional; Lab-On-A-Chip Devices; Microaneurysm; Microfluidic Analytical Techniques; Regional Blood Flow; Retinal Vessels; Rheology
PubMed: 33762307
DOI: 10.1073/pnas.2100697118 -
Translational Vision Science &... Feb 2021To use high-resolution histology to define the associations between microaneurysms, capillary diameter and capillary density alterations in diabetic retinopathy (DR).
PURPOSE
To use high-resolution histology to define the associations between microaneurysms, capillary diameter and capillary density alterations in diabetic retinopathy (DR).
METHODS
Quantitative comparisons of microaneurysm number, capillary density and capillary diameter were performed between eight human donor eyes with nonproliferative DR and six age- and eccentricity-matched normal donor eyes after retinal vascular perfusion labelling. The parafovea, 3-mm, 6-mm, and 9-mm retinal eccentricities were analyzed and associations between microvascular alterations defined.
RESULTS
Mean capillary density was reduced in all retina regions in the DR group (P = 0.013). Microaneurysms occurred in all retina regions in the DR group, but the association between decreased capillary density and microaneurysm number was only significant in the 3-mm (P = 0.040) and 6-mm (P = 0.007) eccentricities. The mean capillary diameter of the DR group (8.9 ± 0.53 µm) was greater than the control group (7.60 ± 0.40 µm; P = 0.033). There was no association between capillary diameter increase and capillary density decrease (P = 0.257) and capillary diameter increase and microaneurysm number (P = 0.147) in the DR group. Within the parafovea of the DR group, capillary density was significantly reduced, and capillary diameter was significantly increased in the deep capillary plexus compared with the superficial and intermediate plexuses (all P < 0.05).
CONCLUSIONS
In DR, capillary density reduction occurs across multiple retina eccentricities with a predilection for the deep capillary plexus. The association between microaneurysm number and capillary density is specific to retina eccentricity. Capillary diameter increase may be an early biomarker of DR. These findings may refine the application of optical coherence tomography angiography techniques for the management of DR.
Topics: Diabetes Mellitus; Diabetic Retinopathy; Fluorescein Angiography; Humans; Microaneurysm; Microscopy, Confocal; Retinal Vessels; Tomography, Optical Coherence
PubMed: 34003893
DOI: 10.1167/tvst.10.2.6