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Developments in Ophthalmology 2017Almost 25 years after its introduction, optical coherence tomography (OCT) is still a crucial test in the evaluation of patients affected by diabetic retinopathy. In... (Review)
Review
Almost 25 years after its introduction, optical coherence tomography (OCT) is still a crucial test in the evaluation of patients affected by diabetic retinopathy. In this chapter, the authors provide an extensive overview of the posterior segment pathological changes induced by diabetes, characterized using OCT. OCT plays a key role in diabetic macular edema (DME) as it assesses related retinal changes both in a qualitative (i.e., DME pattern, presence and aspects of cysts, fluid localization, integrity, and reflectivity of retinal layers) and quantitative (i.e., macula volume, central and sectorial retinal thickness) way, and it is therefore essential for diagnosis, characterization, and follow-up of DME. Diabetic macular ischemia is associated with retinal structural changes which can be investigated using OCT, although its diagnosis relies mostly on fluorescein angiography. Beyond DME and macular ischemia, OCT permits the individuation of many other lesions occurring in the setting of both non-proliferative (i.e., hyperreflective spots, micropseudocysts, hard exudates, microaneurysm, cotton-wool spots) and proliferative (i.e., neovascularization, vitreoschisis, tractional retinal detachment, hemorrhage) retinopathies. OCT provides precious information on several structures, including vitreo-retinal interface, retinal nerve fiber layers, ganglion cell complex, and choroid.
Topics: Diabetic Retinopathy; Humans; Reproducibility of Results; Retina; Tomography, Optical Coherence
PubMed: 28427062
DOI: 10.1159/000459723 -
Advances in Experimental Medicine and... 2020At medical checkups or mass screenings, the fundus examination is effective for early detection of systemic hypertension, arteriosclerosis, diabetic retinopathy, etc. In... (Review)
Review
At medical checkups or mass screenings, the fundus examination is effective for early detection of systemic hypertension, arteriosclerosis, diabetic retinopathy, etc. In most cases, ophthalmologists and physicians grade retinal images by the condition of the blood vessels, lesions. However, human observation does not provide quantitative results, thus blood vessel analysis is an important process in determining hypertension and arteriosclerosis, quantitatively. This chapter describes the latest automated blood vessel extraction using the deep convolution neural network (DCNN). Diabetic retinopathy is a common cardiovascular disease and a major factor in blindness. Therefore, early detection of diabetic retinopathy is very important to preventing blindness. A microaneurysm is an initial sign of diabetic retinopathy, and much research has been conducted for microaneurysm detection. This chapter also describes diabetic retinopathy detection and automated microaneurysm detection using the DCNN.
Topics: Deep Learning; Diabetic Retinopathy; Early Diagnosis; Fundus Oculi; Humans; Microaneurysm
PubMed: 32030666
DOI: 10.1007/978-3-030-33128-3_7 -
Survey of Ophthalmology 2022The electroretinogram (ERG) is a noninvasive, objective technique to evaluate retinal function that has become increasingly important in the study of diabetic... (Review)
Review
The electroretinogram (ERG) is a noninvasive, objective technique to evaluate retinal function that has become increasingly important in the study of diabetic retinopathy. We summarize the principles and rationale of the ERG, present findings from recent clinical studies that have used the full-field ERG, multifocal ERG, and pattern ERG to evaluate neural dysfunction in patients with diabetes, and weigh the strengths and limitations of the technique as it applies to clinical studies and management of patients with diabetic retinopathy. Taken together, ERG studies have provided convincing evidence for dysfunction of the neural retina in patients with diabetes, including those who have no clinically-apparent retinal vascular abnormalities. Recent full-field ERG findings have pointed to the intriguing possibility that photoreceptor function is abnormal in early-stage disease. Pattern ERG data, in conjunction with recently developed photopic negative response analyses, indicate inner retina dysfunction. In addition, multifocal ERG studies have shown spatially localized neural abnormalities that can predict the location of future microaneurysms. Given the insights provided by the ERG, it is likely to play a growing role in understanding the natural history of neural dysfunction in diabetes, as well as providing an attractive outcome measure for future clinical trials that target neural preservation in diabetic retinopathy.
Topics: Color Vision; Diabetes Mellitus; Diabetic Retinopathy; Electroretinography; Humans; Retina
PubMed: 34487740
DOI: 10.1016/j.survophthal.2021.08.011 -
Current Diabetes Reports Dec 2016Diabetic retinopathy is a progressive microvascular disease that leads to increased vessel permeability, retinal ischemia, and retinal neovascularization. Optical... (Review)
Review
Diabetic retinopathy is a progressive microvascular disease that leads to increased vessel permeability, retinal ischemia, and retinal neovascularization. Optical coherence tomography angiography (OCTA) is a novel angiography technique that has the capability to advance our understanding of diabetic eye disease by providing high-resolution images of retinal and choroidal microvasculature blood flow and structure. Using OCTA, the vascular changes of diabetic retinopathy including microaneurysms, retinal non-perfusion, intraretinal microvascular abnormalities, and neovascularization can be clearly visualized. OCTA offers several advantages over fluorescein angiography (FA) in that it is faster, safer, and non-invasive, allows better visualization of retinal vessels in both the superficial and deep capillary layers, and can provide quantitative measurements of areas of non-perfusion of the macula and nerve. OCTA capillary perfusion density maps and average perfusion density values provide an easy way to grade progressive vascular change. Despite these advantages, imaging with OCTA can only provide a limited view of the peripheral retina and is unable to demonstrate leakage, staining, or pooling. OCTA requires patients to maintain good fixation to obtain high-resolution images which can be a challenge for those with severe macular disease. In patients who cannot safely undergo FA, OCTA may serve as an alternative form of angiography that can be safely and more frequently performed for the management of diabetic retinopathy.
Topics: Diabetic Retinopathy; Fluorescein Angiography; Humans; Tomography, Optical Coherence
PubMed: 27766583
DOI: 10.1007/s11892-016-0811-x -
Artificial Intelligence in Medicine Jun 2019The diabetic retinopathy is the main reason of vision loss in people. Medical experts recognize some clinical, geometrical and haemodynamic features of diabetic... (Review)
Review
The diabetic retinopathy is the main reason of vision loss in people. Medical experts recognize some clinical, geometrical and haemodynamic features of diabetic retinopathy. These features include the blood vessel area, exudates, microaneurysm, hemorrhages and neovascularization, etc. In Computer Aided Diagnosis (CAD) systems, these features are detected in fundus images using computer vision techniques. In this paper, we review the methods of low, middle and high level vision for automatic detection and classification of diabetic retinopathy.We give a detailed review of 79 algorithms for detecting different features of diabetic retinopathy during the last eight years.
Topics: Diabetic Retinopathy; Humans; Retina; Retinal Vessels
PubMed: 30448367
DOI: 10.1016/j.artmed.2018.10.009 -
Frontiers in Endocrinology 2023Non-proliferative diabetic retinopathy (NPDR), a common diabetic complication with high morbidity, is featured by impaired visual function and fundus lesions. It has... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Non-proliferative diabetic retinopathy (NPDR), a common diabetic complication with high morbidity, is featured by impaired visual function and fundus lesions. It has been reported that oral Chinese patent medicines (OCPMs) may improve visual acuity and fund signs. However, the best possible OCPMs for NPDR remain questionable and merit further investigation.
METHODS
From inception to October 20, 2022, seven databases were searched for eligible randomized controlled trials (RCTs). The outcomes were clinical effective rate, visual acuity, visual field gray value, microaneurysm volume, hemorrhage area, macular thickness, and adverse events rate. The revised Cochrane risk-of-bias tool (ROB 2) was used to assess the quality of the included studies. Network meta-analysis was performed using R 4.1.3 and STATA 15.0 software.
RESULTS
We included 42 RCTs with 4,858 patients (5,978 eyes). The Compound Danshen Dripping Pill (CDDP) combined with calcium dobesilate (CD) had the most improvement in clinical efficacy rate (SUCRA, 88.58%). The Compound Xueshuantong Capsule (CXC) combined with CD may be the best intervention (SUCRA, 98.51%) for the improvement of visual acuity. CDDP alone may be the most effective treatment option (SUCRA, 91.83%) for improving visual field gray value. The Hexuemingmu Tablet (HXMMT) and Shuangdan Mingmu Capsule (SDMMC) combined with CD may be the most effective treatment for reducing microaneurysm volume and hemorrhage area (SUCRA, 94.48%, and 86.24%), respectively. Referring to reducing macular thickness, CXC combined with CD ranked first (SUCRA, 86.23%). Moreover, all OCPMs did not cause serious adverse reactions.
CONCLUSION
OCPMs are effective and safe for NPDR. CDDP alone, and combined with CD, may be the most effective in improving visual field gray value and clinical efficacy rate, respectively; CXC combined with CD may be the best in enhancing BCVA and reducing macular thickness; HXMMT and SDMMC combined with CD, maybe the most effective regarding microaneurysm volume and hemorrhage area, respectively. However, the reporting of methodology in the primary study is poor, potential biases may exist when synthesizing evidence and interpreting the results. The current findings need to be confirmed by more large-sample, double-blind, multi-center RCTs of rigorous design and robust methods in the future.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/, identifier CRD42022367867.
Topics: Humans; Diabetic Retinopathy; Network Meta-Analysis; Microaneurysm; Randomized Controlled Trials as Topic; Diabetes Mellitus
PubMed: 37077355
DOI: 10.3389/fendo.2023.1144290 -
Modern Pathology : An Official Journal... Dec 2021Intracerebral hemorrhage (ICH) is a significant cause of morbidity and mortality worldwide. Hypertension and cerebral amyloid angiopathy (CAA) are the most common causes...
Intracerebral hemorrhage (ICH) is a significant cause of morbidity and mortality worldwide. Hypertension and cerebral amyloid angiopathy (CAA) are the most common causes of primary ICH, but the mechanism of hemorrhage in both conditions is unclear. Although fibrinoid necrosis and Charcot-Bouchard aneurysms (CBAs) have been postulated to underlie vessel rupture in ICH, the role and significance of CBAs in ICH has been controversial. First described as the source of bleeding in hypertensive hemorrhage, they are also one of the CAA-associated microangiopathies along with fibrinoid necrosis, fibrosis and "lumen within a lumen appearance." We describe clinicopathologic findings of CBAs found in 12 patients out of over 2700 routine autopsies at a tertiary academic medical center. CBAs were rare and predominantly seen in elderly individuals, many of whom had multiple systemic and cerebrovascular comorbidities including hypertension, myocardial and cerebral infarcts, and CAA. Only one of the 12 subjects with CBAs had a large ICH, and the etiology underlying the hemorrhage was likely multifactorial. Two CBAs in the basal ganglia demonstrated associated microhemorrhages, while three demonstrated infarcts in the vicinity. CBAs may not be a significant cause of ICH but are a manifestation of severe cerebral small vessel disease including both hypertensive arteriopathy and CAA.
Topics: Aged; Aged, 80 and over; Arteriosclerosis; Atherosclerosis; Brain Diseases; Cerebral Amyloid Angiopathy; Cerebral Hemorrhage; Cerebrovascular Circulation; Female; Humans; Hypertension; Male; Microaneurysm; Middle Aged; Risk Factors
PubMed: 34326486
DOI: 10.1038/s41379-021-00847-1 -
Vestnik Oftalmologii 2021Diabetic retinopathy is a microvascular pathology, which is the most common complication of diabetes mellitus. Improvement of instrumental diagnostics of retinal... (Review)
Review
Diabetic retinopathy is a microvascular pathology, which is the most common complication of diabetes mellitus. Improvement of instrumental diagnostics of retinal pathologies has contributed to identification of various phenotypes of the progression of ocular fundus pathology in diabetes based on specific changes in the retina - biomarkers. In particular, microaneurysms initially described in diabetes, which are a manifestation of a wide range of systemic pathologies and retinal diseases, are an indicator of the severity of diabetic retinopathy. Dynamic changes in the number of microaneurysms are a confirmed prognostic biomarker of clinically significant macular edema. In diabetic retinopathy, microaneurysms are one of the earliest recognizable signs, and the dynamic of their formation and disappearance may serve as a predictor for the disease progression. This literature review presents the characteristics of microaneurysms based on various imaging techniques, and analyses the link between structural features and dynamic changes in microaneurysms, and progression of diabetic retinopathy.
Topics: Biomarkers; Diabetes Mellitus; Diabetic Retinopathy; Fluorescein Angiography; Humans; Microaneurysm; Retinal Vessels; Tomography, Optical Coherence
PubMed: 34669341
DOI: 10.17116/oftalma2021137052300 -
Ophthalmology. Retina Feb 2020In diabetic retinopathy (DR), OCT angiography (OCTA) could not image all fluorescein angiography (FA)-detected microaneurysms. We investigated whether multiple image... (Observational Study)
Observational Study
PURPOSE
In diabetic retinopathy (DR), OCT angiography (OCTA) could not image all fluorescein angiography (FA)-detected microaneurysms. We investigated whether multiple image averaging could enhance the microaneurysm detection capability of OCTA in patients with DR.
DESIGN
Prospective and cross-sectional observational study.
PARTICIPANTS
Consecutive 31 patients (n = 62 eyes) with DR.
METHODS
All eyes underwent FA and 3 × 3 mm fovea-centered OCTA images were obtained using 2 devices: RTVue XR Avanti (Optovue Inc, Fremont, CA) and OCT HS-100 (Canon Inc, Toyko, Japan). OCTA imaging (HS-100) was performed 10 consecutive times. Microaneurysm detection capability was compared among 5 OCTA images (single image, ×3, ×5, and ×10 averaged images and single scan image with the RTVue XR Avanti device).
MAIN OUTCOME MEASURES
Microaneurysm detection capability and the correlation between microaneurysm clinical characteristics or morphology and the extent of image averaging required for OCTA detection.
RESULTS
A total of 415 microaneurysms could be analyzed in 31 eyes from 25 patients. Microaneurysms detected on single image, ×3, ×5, and ×10 averaged OCTA images were 144 (34.7%), 227 (54.7%), 285 (68.7%), and 306 (73.7%), respectively. Microaneurysm detection capability was significantly increased with increased image averaging. Microaneurysm detection with OCTA was not correlated with retinal thickness, FA leakiness, and indocyanine green angiogram detection or the number of averaged images, whereas there was significant correlation between microaneurysm morphology and microaneurysm visibility by the image-averaging process for 4 morphologies, particular the focal bulge types (P < 0.01).
CONCLUSIONS
In DR, multiple image averaging is useful for increasing the microaneurysm detection capability of OCTA, especially for focal bulge-type microaneurysms.
Topics: Cross-Sectional Studies; Female; Fluorescein Angiography; Fovea Centralis; Fundus Oculi; Humans; Male; Microaneurysm; Middle Aged; Prospective Studies; Retinal Vessels; Tomography, Optical Coherence
PubMed: 31753811
DOI: 10.1016/j.oret.2019.09.010 -
Ophthalmology Jul 2017To evaluate detection of hemorrhage and/or microaneurysm (H/Ma) using ultrawide field (UWF) retinal imaging as compared with standard Early Treatment Diabetic... (Comparative Study)
Comparative Study
OBJECTIVE
To evaluate detection of hemorrhage and/or microaneurysm (H/Ma) using ultrawide field (UWF) retinal imaging as compared with standard Early Treatment Diabetic Retinopathy Study (ETDRS) 7-field photographs (ETDRS photos).
DESIGN
Single-site comparative study of UWF images and ETDRS photos.
PARTICIPANTS
One hundred twenty-six eyes of 69 patients with no diabetic retinopathy (DR) or mild or moderate nonproliferative DR (NPDR).
METHODS
Stereoscopic 200° UWF images and stereoscopic 35mm 30° 7-field color photographs were acquired on the same visit. Images were graded for severity and distribution of H/Ma. H/Mas were counted in ETDRS fields 2 to 7 in both ETDRS photos and UWF images. H/Mas in the UWF peripheral fields were also counted.
MAIN OUTCOME MEASURES
Kappa (κ) and weighted κ statistics for agreement. Number of H/Ma within and outside ETDRS fields identified in UWF images and ETDRS photos.
RESULTS
Distribution of DR severity by ETDRS photos was 24 (19.0%) no DR, 48 (38.1%) mild NPDR, and 54 (42.9%) moderate NPDR. A total of 748 of 756 fields (98.9%) were gradable for H/Mas on ETDRS photos and UWF images. Simple κ/weighted κ statistics for severity of H/Ma: all fields 0.61/0.69, field 2 0.70/0.77, field 3 0.62/0.73, field 4 0.50/0.62, field 5 0.54/0.65, field 6 0.64/0.70, and field 7 0.58/0.63 with overall exact agreement in 81.3% and within 1 step in 97.9% of fields. A greater proportion of fields was graded a more severe H/Ma level in UWF images than in the corresponding ETDRS photos (UWF: 12.7% vs.
ETDRS
6.5%). Evaluating comparable areas in UWF images and ETDRS photos (fields 2-7), a mean of 42.8 H/Mas were identified using ETDRS photos and 48.8 in UWF images (P = 0.10). An additional mean of 21.3 H/Mas (49.8% increase, P < 0.0001) were identified in the peripheral fields of the UWF images.
CONCLUSIONS
There is good to excellent agreement between UWF images and ETDRS photos in determining H/Ma severity, with excellent correlation of H/Ma counts within ETDRS photo fields. UWF peripheral fields identified 49.8% more H/Ma, suggesting a more severe H/Ma in 12.7% of eyes. Given the additional lesions detected in peripheral fields and the known risks associated with H/Ma and peripheral lesions, quantification of H/Ma using UWF images may provide a more accurate representation of DR disease activity and potential greater accuracy in predicting DR progression.
Topics: Diabetic Retinopathy; Disease Progression; Follow-Up Studies; Humans; Microaneurysm; Photography; Prospective Studies; ROC Curve; Retina; Retinal Hemorrhage; Severity of Illness Index; Time Factors
PubMed: 28336057
DOI: 10.1016/j.ophtha.2017.02.012