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Diabetic Retinopathy (DR) is a common complication of diabetes that can lead to blindness of people. Detecting DR at the earliest stage is essential to prevent irreversible eye damage. Microaneurysm dots are the first signs of DR. As the dots are tiny and of low contrast, detecting mild DR is a very challenging task. Federated learning (FL) preserves data privacy, which is a major concern for medical image processing. FL is a collaborative learning method, which shares only the model parameters with a server, without sharing the patient data to a central server. Inspired by classical FL, we propose a federated learning-based quantum neural network (federated QNN) for this task. We implemented the models with limited samples and few learnable parameters from the E-ophtha and Retina MNIST datasets. The cross-evaluation efficiency of the proposed federated quantum neural network system for privacy-preserving early detection of diabetic retinopathy (FQPDR) in Kaggle dataset images indicates the robustness of the light weight learning models. FQPDR performances are inspiring while considering existing non-FL and FL methods. [ABSTRACT FROM AUTHOR]

Senile plaque blue autofluorescence was discovered around 40 years ago, however, its impact on Alzheimer's disease (AD) pathology has not been fully examined. We analyzed senile plaques with immunohistochemistry and fluorescence imaging on AD brain sections and also Aβ aggregation in vitro. In DAPI or Hoechst staining, the nuclear blue fluorescence could only be correctly assigned after subtracting the blue plaque autofluorescence. The flower-like structures wrapping dense-core blue fluorescence formed by cathepsin D staining could not be considered central-nucleated neurons with defective lysosomes since there was no nuclear staining in the plaque core when the blue autofluorescence was subtracted. Both Aβ self-oligomers and Aβ/hemoglobin heterocomplexes generated blue autofluorescence. The Aβ amyloid blue autofluorescence not only labels senile plaques but also illustrates red cell aggregation, hemolysis, cerebral amyloid angiopathy, vascular plaques, vascular adhesions, and microaneurysms. In summary, we conclude that Aβ-aggregation-generated blue autofluorescence is an excellent multi-amyloidosis marker in Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Aim of study. To retrospectively assess the occurrence and consequences of subarachnoid haemorrhages (SAH) caused by ruptured intracranial aneurysms (RIA), particularly focusing on the treatment outcomes of small aneurysms treated with either endovascular embolisation or surgical intervention. Material and methods. We retrospectively analysed data from 408 patients (144 males and 264 females) who were hospitalised between 2013 and 2022 at the Department of Neurosurgery and Neurology in University Hospital Nr 2 in Bydgoszcz, Poland. Clinical conditions at admission, assessed using the Glasgow Coma Scale, Hunt-Hess scale (H-H), modified Rankin scale (mRS), as well as age and sex, were recorded. Additionally, aneurysm data including size, localisation, and the method and outcome of endovascular or surgical treatment were examined. Results. Among the 408 patients hospitalised due to SAH, the most common localisation of the 375 RIAs was the anterior communicating artery (AcomA) complex (111 cases, 29.6%), followed by the medial cerebral artery (MCA) (95 cases, 25.3%), internal carotid artery (ICA) (94 cases, 25%), and the vertebrobasilar complex (consisting of the basilar artery (BA) -- 25 cases, vertebral artery (VA) -- 13 cases, anterior inferior cerebellar artery (AICA) -- one case, and posterior inferior cerebellar artery (PICA) -- four cases), which accounted for 43 SAH cases (11.46%). In 33 cases, neither RIA nor a haemorrhage source was identified, or arteriography showed no cerebral arteries contrast flow. Among the examined group of 375 RIAs, 45 (12%) were microaneurysms (≤ 3 mm), 35 (9%) were small aneurysms (3 ≤ 5 mm), 89 (24%) were medium-sized (5 ≤ 7 mm), and 151 (40%) were large aneurysms (> 7 mm), serving as the source of SAH. A better outcome was significantly associated with lower initial H-H grade (p < 0.001), higher GCS (p < 0.001), lower mRS at admission (p < 0.001), younger age (p < 0.001), smaller size (≤ 3 mm) (p < 0.001), and endovascular treatment (p < 0.001). Conclusions. In this series, over 21% of patients suffered from SAH resulting from ruptured small aneurysms (≤ 5 mm), with 12% specifically attributed to ruptured very small aneurysms (≤ 3 mm), despite large aneurysms (> 7 mm) being the most prevalent source of bleeding in 40% of cases. A worse prognosis was primarily associated with the severity of SAH, reflected in poorer clinical status at admission and older age. Endovascular embolisation was found to be effective and associated with better outcomes compared to surgical treatment. [ABSTRACT FROM AUTHOR]

A 40-year-old female with a history of ischemic moyamoya disease treated with indirect revascularization at ages 12 and 25 years presented with a sudden severe headache. Imaging studies revealed focal parenchymal hemorrhage and acute subdural hematoma, confirming a microaneurysm formed on the postoperative transosseous vascular network as the source of bleeding. Conservative management was performed, and no hemorrhage recurred during the 6-month follow-up period. Interestingly, follow-up imaging revealed spontaneous occlusion of the microaneurysm. However, due to the rarity of this presentation, the efficacy of conservative treatment remains unclear. Further research on similar cases is warranted. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate and compare the efficacy and safety of retinal laser photocoagulation (PRP) alone, PRP with aflibercept 3+PRN, and PRP with aflibercept 5+PRN in patients with both high-risk proliferative diabetic retinopathy (PDR) and diabetic macular edema (DME). Methods: Overall, 170 patients with high-risk PDR and DME (170 eyes from 170 patients) who visited our ophthalmology clinic from December 2018 to December 2020 were divided into the PRP (n=58), aflibercept 5+PRN with PRP (n=53), and aflibercept 3+PRN with PRP (n= 59) groups. General information, such as age, sex, and eye category, was obtained. Moreover, best-corrected visual acuity (BCVA), baseline central macular foveal thickness (CFT), microaneurysm (MA), area of neovascularization (NV), area of hard exudate (HE), and cytokine levels in atrial fluid before and after treatment, were assessed. The c2 test was used for comparison between groups for statistical data. Analysis of variance was used for the statistical description of measurement data, independent samples were analyzed using Student's t-test, and Student-Newman-Keuls test was used for group comparisons. Differences were considered statistically significant at P < 0.05. Results: After treatment, no significant improvement in the BCVA (logMAR) of patients in the PRP group was observed. The BCVA (log MAR) decreased from 0.72 ± 0.17 and 0.74 ± 0.17 to 0.50 ± 0.13 and 0.53 ± 0.17 in PRP with aflibercept 5+PRN and PRP with aflibercept 3+PRN groups, respectively, with a statistically significant difference compared to those in the PRP group (P<0.05 in all cases). However, no statistically significant difference was observed between the combined treatment groups (P>0.05). The CFT in the PRP-only group decreased slightly from 361.80 ± 36.70 µm to 353.86 ± 40.88 µm, with no statistically significant difference (P>0.05), whereas the CFT in the aflibercept 5 +PRN with PRP and aflibercept 3+PRN with PRP groups decreased from 356.57 ± 37.57 µm and 358.17 ± 44.66 µm to 284.87 ± 31.52 µm and 303.19 ± 37.00 µm, respectively, with statistically significant differences before and after treatment (P<0.05 for both groups). Statistically significant differences were observed in CFT between the three groups after treatment (P<0.05 in all cases). The number of MA (pcs) in the PRP, aflibercept 5+PRN with PRP, and aflibercept 3+PRN with PRP groups decreased from 118.34 ± 27.96, 118.60 ± 33.34, and 116.59 ± 28.95 to 92.95 ± 29.04, 44.60 ± 20.73, and 54.26 ± 25.43, respectively. The two-way comparison of the three groups revealed statistically significant differences in MA (P<0.05 in all cases). In the three groups, NV decreased from 1.00 ± 0.21 mm², 1.01 ± 0.18 mm², and 0.98 ± 0.20 mm² before treatment to 0.49 ± 0.17 mm², 0.31 ± 0.16 mm², and 0.38 ± 0.14 mm², respectively, with statistically significant differences (P<0.05 in all cases). After 12 months of treatment, 13, 18, and 18 patients had reduced HE area in the PRP-only, aflibercept 5+PRN with PRP, and aflibercept 3+PRN with PRP groups, respectively, with statistically significant differences (P<0.05 in all cases). After 12 months of treatment, vascular endothelial growth factor, monocyte chemoattractant protein-1, and glial fibrilliary acidic protein levels (pg/mL) in the aqueous humor decreased in both combined treatment groups compared with that at baseline, with statistically significant differences; however, no significant difference was observed between the two combined treatment groups (P>0.05). Conclusion: Aflibercept 5+PRN combined with PRP was safe and effective in treating patients with high-risk PDR and DME, and was more effective than PRP-only and aflibercept 3+PRN with PRP in improving CFT and MA. [ABSTRACT FROM AUTHOR]

Patients with diabetes usually develop a condition called diabetic retinopathy (DR), resulting from retinal damage. This impairment usually happens when the glucose levels in the blood are elevated, finally causing a blockage in the blood vessels that feed a part of the eye called the retina and finally severing it from the blood supply. Therefore, the eye attempts to produce fresh blood cells. But these cells are either poorly developed or weak. So, it can be leaked out easily. Hence, to lessen the severe effects of this disease, these patients must be diagnosed as soon as possible. Earlier, a number of approaches were put forth to recognise this illness using machine learning algorithms, image processing, and other techniques. The diagnosis process of this disease involves pre-processing of coloured images of the fundus, extraction of clinical features and classification of retinopathy. In this research, fundus photography of the retina is utilised to accelerate the detection of various kinds of retinopathy caused by diabetes based on convolutional neural network (CNN) pre-trained transfer learning algorithm. Inception V3 and Xception are used in this model to determine and categorise diabetic retinopathy, respectively. As a result, people with this disease can lower their risk of exposure to permanent blindness. [ABSTRACT FROM AUTHOR]

Purpose: To report a case of a refractory foveal microaneurysm (MA) that was successfully treated by use of a new surgical procedure. Observations: This study involved a 79-year-old female with an active foveal MA associated with branch retinal vein occlusion in her left eye. Despite anti-vascular endothelial growth factor treatments, the MA remained active without closure, and best-corrected visual acuity (VA) gradually decreased from 20/20 to 20/200. After our new surgical procedure was explained in detail to the patient, written informed consent was obtained from the patient and the surgery was performed. Briefly, following pars plana vitrectomy, the internal limiting membrane in her left eye was peeled and the retina of the external wall of the MA was then gently incised. The exposed MA was then directly grabbed and pulled up onto the retina using 27-gauge microforceps, and photocoagulation was performed. At 3-months postoperative, closure of the MA and improvement in the retinal findings were observed, and best-corrected VA improved to 20/67. Conclusions and importance: We report a case of a refractory foveal MA that was successfully treated with a novel surgical technique that closed the MA, avoided thermal damage to the surrounding tissue, and resulted in improved postoperative VA.

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.

Abstract Diabetic retinopathy (DR) is one of the leading causes of blindness for people suffering from diabetes. Microaneurysm (MA) is the initial symptom of DR. MA is a lesion based disease which starts as small red spots on the retina and increases in size as the DR progresses which finally leads to blindness. So eliminating the lesion can effectively prevent DR at an early stage. However, due to complex retinal structure, different brightness and contrast of fundus images with effects of factors such as different patients, environment changes, and difference in acquisition equipment, it is difficult for existing detection algorithms to achieve accurate results of MA detection and location. Therefore, the detection algorithm of improved YOLOv4 (YOLOv4‐Pro) was proposed. First, an improved Fuzzy C‐Means (IFCM) clustering algorithm was proposed to optimize anchor parameters of target samples to improve matching results between anchors and feature graphs. In order to control noise and improve efficiency, a median filtering method was employed to update the criterion function of the original FCM algorithm, and a K‐means algorithm was employed to initialize clustering. Second, a SENet attention module was added in the backbone of YOLOv4 to enhance key information and suppress background, improving the confidence of MA effectively. Finally, the spatial pyramid pooling (SPP) module was added to the neck to enhance the acceptance domain of the output characteristics of the backbone network, and profits separating of important context information. The improved YOLOv4 with IFCM was verified on the Kaggle DR dataset and compared with other methods. Experimental results show that optimizing the prior frame with the IFCM algorithm can make it suitable to frame the Kaggle DR dataset, which improves the detection accuracy of the network by nearly 5%, and provides a nice performance on detection and location of MA in fundus images. This would help ophthalmologists finding the exact location of MA on retina, thereby simplifying the process and eliminating any manual intervention.

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. [ABSTRACT FROM AUTHOR]

The aim of this study is to correlate small dot hyper‐reflective foci (HRF) observed in spectral domain optical coherence tomography (SD‐OCT) scans of an animal model of hyperglycaemia with focal electroretinography (fERG) response and immunolabelling of retinal markers. The eyes of an animal model of hyperglycaemia showing signs of diabetic retinopathy (DR) were imaged using SD‐OCT. Areas showing dot HRF were further evaluated using fERG. Retinal areas enclosing the HRF were dissected and serially sectioned, stained and labelled for glial fibrillary acidic protein (GFAP) and a microglial marker (Iba‐1). Small dot HRF were frequently seen in OCT scans in all retinal quadrants in the inner nuclear layer or outer nuclear layer in the DR rat model. Retinal function in the HRF and adjacent areas was reduced compared with normal control rats. Microglial activation was detected by Iba‐1 labelling and retinal stress identified by GFAP expression in Müller cells observed in discrete areas around small dot HRF. Small dot HRF seen in OCT images of the retina are associated with a local microglial response. This study provides the first evidence of dot HRF correlating with microglial activation, which may allow clinicians to better evaluate the microglia‐mediated inflammatory component of progressive diseases showing HRF. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is one of the leading causes of blindness for people suffering from diabetes. Microaneurysm (MA) is the initial symptom of DR. MA is a lesion based disease which starts as small red spots on the retina and increases in size as the DR progresses which finally leads to blindness. So eliminating the lesion can effectively prevent DR at an early stage. However, due to complex retinal structure, different brightness and contrast of fundus images with effects of factors such as different patients, environment changes, and difference in acquisition equipment, it is difficult for existing detection algorithms to achieve accurate results of MA detection and location. Therefore, the detection algorithm of improved YOLOv4 (YOLOv4‐Pro) was proposed. First, an improved Fuzzy C‐Means (IFCM) clustering algorithm was proposed to optimize anchor parameters of target samples to improve matching results between anchors and feature graphs. In order to control noise and improve efficiency, a median filtering method was employed to update the criterion function of the original FCM algorithm, and a K‐means algorithm was employed to initialize clustering. Second, a SENet attention module was added in the backbone of YOLOv4 to enhance key information and suppress background, improving the confidence of MA effectively. Finally, the spatial pyramid pooling (SPP) module was added to the neck to enhance the acceptance domain of the output characteristics of the backbone network, and profits separating of important context information. The improved YOLOv4 with IFCM was verified on the Kaggle DR dataset and compared with other methods. Experimental results show that optimizing the prior frame with the IFCM algorithm can make it suitable to frame the Kaggle DR dataset, which improves the detection accuracy of the network by nearly 5%, and provides a nice performance on detection and location of MA in fundus images. This would help ophthalmologists finding the exact location of MA on retina, thereby simplifying the process and eliminating any manual intervention. [ABSTRACT FROM AUTHOR]

Background and Objectives: This study aimed to elucidate the role of laser photocoagulation therapy in the treatment of diabetic macular edema (DME) as an alternative to, or in conjunction with, the first-line treatment, anti-vascular endothelial growth factor (VEGF). Materials and Methods: A comprehensive literature search to identify studies that evaluated the efficacy of laser photocoagulation therapy in the management of DME was performed. The relevant findings of the efficacy of focal/grid laser therapy from data in randomized, controlled trials were synthesized, and the potential of new laser technologies, such as navigated laser systems, pattern scan lasers, and subthreshold lasers, was explored. The usefulness of multimodal imaging-guided laser therapy was also evaluated, with a focus on the potential contribution to anti-VEGF therapy. Results: Focal laser photocoagulation targeting microaneurysms remains an effective therapeutic approach to chronic refractory edema, despite the widespread use of anti-VEGF therapy. To achieve the best possible treatment outcomes, precise identification of microaneurysms is essential. This requires the use of multimodal imaging-guided, highly accurate, minimally invasive coagulation techniques. Subthreshold laser therapy can also reduce the frequency of anti-VEGF injections and minimize treatment burden. Conclusions: Further studies are needed to determine the optimal timing and settings for laser photocoagulation therapy and the potential of new laser technologies in the management of DME. Nevertheless, laser photocoagulation therapy plays an important role in the management of DME, in conjunction with anti-VEGF therapy. [ABSTRACT FROM AUTHOR]

Junichi Itou,1,&ast; Kei Furushima,1,&ast; Masatoshi Haruta,1 Nobuhiro Kato,1 Rikki Arai,1 Kenichiro Mori,2 Keijiro Ishikawa,2 Shigeo Yoshida1 1Department of Ophthalmology, Kurume University School of Medicine, Kurume, Japan; 2Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan&ast;These authors contributed equally to this workCorrespondence: Shigeo Yoshida, Department of Ophthalmology, Kurume University School of Medicine, 67 Asahi-machi, Kurume, Fukuoka, 830-0011, Japan, Tel +81-942-317574, Fax +81-942-370324, Email yoshi@med.kurume-u.ac.jpPurpose: Intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) agents reduces microaneurysms in patients with diabetic macular edema (DME). However, residual anti-VEGF-resistant telangiectatic capillaries (TelCaps) have been reported. In this study, we investigated changes in the size of TelCaps after intravitreal injection of anti-VEGF agents in DME.Patients and Methods: Indocyanine green angiography (IA) and optical coherence tomography were performed before and 3 months after the intravitreal injection of anti-VEGF agents (pro re nata regimen after three monthly loading doses) in 12 eyes of 12 patients (7 males and 5 females, mean age 65.2 ± 8.8 years) with DME. The number and size of TelCaps within a 6-mm diameter macular region of the edema were measured using optical coherence tomography B-scan images overlaid on IA images.Results: There were significant reductions in the number and size of TelCaps between the baseline and 3 months after anti-VEGF agent administration (P < 0.05 and P < 0.0001, respectively). The maximum corrected visual acuity (logMAR visual acuity) and the central macular thickness after anti-VEGF therapy were significantly improved (P < 0.01 and P < 0.02, respectively). The TelCaps remaining after loading three consecutive anti-VEGF agents had a significantly larger mean size at baseline than the TelCaps that resolved after the treatment (P < 0.03).Conclusion: Our study demonstrated that intravitreal injection of anti-VEGF agents could reduce TelCap size in patients with DME. We propose that larger-sized TelCaps detected by IA might be useful predictors of refractory DME, which could thus be principal targets of laser photocoagulation.Keywords: anti-VEGF therapy, diabetic retinopathy, TelCap, indocyanine green angiography, microaneurysm, optical coherence tomography

Senile plaques are a pathological hallmark of Alzheimer's disease (AD), yet the mechanism underlying their generation remains unknown. Beta‐amyloid peptide (Aβ) is a major component of senile plaques. We analysed AD brain tissues with histochemistry, immunohistochemistry and fluorescence imaging to examine the neural, vascular or blood Aβ contribution to senile plaque development. We found little neural marker co‐expression with plaque Aβ, while co‐expression of blood markers, such as Haemin and ApoE, was abundant. The plaque cores were structured with vascular and glial proteins outside and blood metabolites inside, co‐localizing with a characteristic of Hoechst staining‐independent blue autofluorescence. Erythrocyte‐interacting Aβ is linked to coagulation, elevated calcium and blue autofluorescence, and it is associated with intravascular haemolysis, atherosclerosis, cerebral amyloid angiopathy, microaneurysm, and often with Cathepsin D co‐expression. We identified microaneurysms as major sites of amyloid formation. Our data suggest that senile plaques arise from Aβ‐ and Cathepsin D‐enriched mixtures leaking out during intravascular haemolysis and microaneurysm rupture. [ABSTRACT FROM AUTHOR]

Purpose: To explored Relationship between uric acid and cerebral amyloid angiopathy; Materials and methods: ZO-1 and RAGE in HBMECs were detected by western blotting, and then, we analyzed ZO-1, occludin, and RAGE mRNA expression levels in different treatment groups using RTPCR. Cell counts and the relative αSMA fluorescence intensity were measured in order to evaluate the protective effect of uric acid against injury to HBVSMCs. Analysis of variance showed that LDH leakage rate was used to verify the uric acid protective effect on the injury induced by Aβ1–40. After that, the level of uric acid in serum and Aβ1–40 in brain tissue was analyzed by western blotting and immunohistochemistry to evaluate the protective effect of uric acid in the brain of APP23 mice. Meanwhile, Occludin, ZO-1, and RAGE protein levels were measured by western blotting; Results: Uric acid reduced the negative effects of Aβ on the vascular endothelium and smooth muscle cells and protected the vascular wall in vitro. In APP23 mice, Aβ1–40 and Aβ1–42 levels were significantly elevated in brain tissues and further increased after uric acid concentration was decreased. In APP23 mice, ZO-1 and occludin expression levels were both significantly lower than those in wild-type animals. After uric acid concentration was lowered in APP23 mice, ZO-1 and occludin expression levels were significantly lower than those in untreated animals; Conclusions: Uric acid in the blood protects the blood vessels from CAA damage to the blood vessel wall, and reduces the occurrence of cerebral hemorrhage. [ABSTRACT FROM AUTHOR]

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.

Blood flow within the vasculature of the retina has been found to influence the progression of diabetic retinopathy. In this research cell resolved blood flow simulations are used to study the pulsatile flow of whole blood through a segmented retinal microaneurysm. Images were collected using adaptive optics optical coherence tomography of the retina of a patient with diabetic retinopathy, and a sidewall (sacciform) microaneurysm was segmented from the volumetric data. The original microaneurysm neck width was varied to produce two additional aneurysm geometries in order to probe the influence of neck width on the transport of red blood cells and platelets into the aneurysm. Red blood cell membrane stiffness was also increased to resolve the impact of rigid red blood cells, as a result of diabetes, in blood flow. Wall shear stress and wall shear stress gradients were calculated throughout the aneurysm domains, and the quantification of the influence of the red blood cells is presented. Average wall shear stress and wall shear stress gradients increased due to the increase of red blood cell membrane stiffness. Stiffened red blood cells were also found to induce higher local wall shear stress and wall shear stress gradients as they passed through the leading and draining parental vessels. Stiffened red blood cells were found to penetrate the aneurysm sac more than healthy red blood cells, as well as decreasing the margination of platelets to the vessel walls of the parental vessel, which caused a decrease in platelet penetration into the aneurysm sac. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) – one of the diabetes complications – is the leading cause of blindness among the age group of 20–74 years old. Fortunately, 90% of these cases (blindness due to DR) could be prevented by early detection and treatment via manual and regular screening by qualified physicians. The screening of DR is tedious, which can be subjective, time-consuming, and sometimes prone to misclassification. In terms of accuracy and time, many automated screening systems based on image processing have been developed to improve diagnostic performance. However, the accuracy and consistency of the developed systems are largely unaddressed, where a manual screening process is still the most preferred option. The main contribution of this paper is to analyse the accuracy and consistency of microaneurysm (MA) detection via image processing by focusing on Otsu's multi-thresholding as it has been shown to work very well in many applications. The analysis was based on Monte Carlo statistical analysis using synthetic retinal images of retinal images under variation of all stages of DR, retinal, and image parameters – intensity difference between MAs and blood vessels (BVs), MA size, and measurement noise. Then, the conditions – in terms of obtainable retinal and image parameters – that guarantee accurate and consistent MA detection via image processing were extracted. Finally, the validity of the conditions to guarantee accurate and consistent MA detection was verified using real retinal images. The results showed that MA detection via image processing is guaranteed to be accurate and consistent when the intensity difference between MAs and BVs is at least 50% and the sizes of MAs are from 5 to 20 pixels depending on measurement noise values. These conditions are very important as a guideline of MA detection for DR. [ABSTRACT FROM AUTHOR]

Background and Objectives: The presence of refractory cases resistant to anti-vascular endothelial growth factor (VEGF) therapy for diabetic macular edema (DME) is a problem in clinical practice. This study aimed to explore the less responsive area of optical coherence tomography (OCT) 3D map the characteristics of naïve DME cases after their first anti-VEGF. Materials and Methods: In 46 patients with DME who received an intravitreal injection of anti-VEGF agents, retinal thickness in 100 sections of the macular area was measured by 3D-mapping mode using OCT before and 1 month after injection. The density of the microaneurysm (MA) was calculated using merged images of the OCT map and fluorescein angiography. Results: One month after injection, the central retinal thickness significantly decreased (p < 0.0001). In severe edema (retinal thickness more than 500 µm), the area percentages with a reduction rate of the retinal thickness greater than 30% and less than 5% were 6.4 ± 6.6% and 10.1 ± 4.6%, respectively. The reduction rate of the retinal thickness varied from section to section. The mutual distance between the areas of maximum thickness before and after the injection averaged 1.22 ± 0.62 mm apart. The reduction rate of retinal thickness in the thickest region before injection was significantly higher (p = 0.02), and that in the thickest region after injection was lower (p = 0.001) than in the other regions. MA density in the residual edema was significantly higher than in the edema-absorbed area (p = 0.03). Conclusion: DME has areas that show low response to the reduction in retinal thickness with anti-VEGF therapy. A high density of MA may be associated with this pathogenesis. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) frequently appears in diabetic patients. It is initially asymptomatic, but can progress to blindness. Screening studies for its diagnosis are performed in many countries by means of photographing the eye retina with special fundus-cameras. These studies are aimed at revealing the presence of microaneurysms (MAs) on the retina, which are the primary signs of DR. The wide variety of cameras, peculiarities of retina illumination, FOV angles, and sizes of digital images has complicated the development of a reliable and universal approach to analyzing retina images by machine-learning methods. In this paper, we consider the problem of choosing the size and shape of a unified template for representing the data of an arbitrary retinal image for subsequent automated DR screening. It is experimentally proved that it is possible to extract a square inscribed in the FOV region from each retinal image and compress it to the size of 512 × 512 pixels. This is the minimum allowable size of the template. It preserves the required number of MAs for DR screening by machine-learning methods. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is a chronic disease that may cause vision loss in diabetic patients. Microaneurysms which are characterized by small red spots on the retina due to fluid or blood leakage from the weak capillary wall often occur during the early stage of DR, making screening at this stage is essential. In this paper, an automatic screening system for early detection of DR in retinal images is developed using a combined shape and texture features. Due to minimum number of hand-crafted features, the computational burden is much reduced. The proposed hybrid multi-kernel support vector machine classifier is constructed by learning a kernel model formed as a combination of the base kernels. This approach outperforms the recent deep learning techniques in terms of the evaluation metrics. The efficiency of the proposed scheme is experimentally validated on three public datasets - Retinopathy Online Challenge, DIARETdB1, MESSIDOR, and AGAR300 (developed for this study). Studies reveal that the proposed model produced the best results of 0.503 in ROC dataset, 0.481 in DIARETdB1, and 0.464 in the MESSIDOR dataset in terms of FROC score. The AGAR300 database outperforms the existing MA detection algorithm in terms of FROC, AUC, F1 score, precision, sensitivity, and specificity which guarantees the robustness of this system. [ABSTRACT FROM AUTHOR]

Background and objectives To investigate changes in retinal vascular plexuses, choriocapillaris, along with microcirculation of optic nerve head (ONH), in patients with type 2 diabetes mellitus without clinically evident retinopathy and healthy controls using optical coherence tomography angiography (OCTA). Patients and methods This is a prospective, cross-sectional observational study that included 20 eyes of normal healthy controls (group 1) and 20 eyes of diabetic patients without clinically evident retinopathy (group 2). All participants underwent OCTA examination (RTVue-XR Avanti; Optovue). Average and parafoveal vessel density in superficial capillary plexus (SCP), deep capillary plexus, choriocapillaris vessel density, foveal avascular zone area and perimeter, and vessel density inside ONH and in peripapillary region were compared between groups. Microaneurysms and capillary nonperfusion were taken into analysis. glycated hemoglobin and serum creatinine were assessed for diabetic patients. Results Group 2 showed statistically significant lower average vessel densities of SCP and deep capillary plexus (P

Diabetic retinopathy (DR) is a complication of diabetes mellitus that leads to vision loss if not treated timely. Microaneurysms (MA) is the first clinical sign of DR. An automatic MA detection method through retinal fundus images has been proposed in this paper. The MA detection method consists of three steps: preprocessing, MA candidate detection, and pixel-wise classification. A novel convolutional neural network (CNN) architecture has been proposed in this paper to train MA and non-MA patches, and the majority voting technique has been used to detect the MA patches. The presented method has been evaluated using an openly available dataset, namely Retinopathy Online Challenge (ROC). The proposed method produces 92% of area under the receiver operating characteristics (AUC) curve, which is better than other state-of-the-art methods. The developed CNN architecture produced the highest accuracy even for fewer images, which helps effective DR screening. [ABSTRACT FROM AUTHOR]

Yuya Esaki, Yoshio Hirano, Ryo Kurobe, Yusuke Yasuda, Taneto Tomiyasu, Norihiro Suzuki, Tsutomu Yasukawa, Munenori Yoshida, Yuichiro Ogura Department of Ophthalmology & Visual Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, JapanCorrespondence: Yoshio HiranoDepartment of Ophthalmology & Visual Science, Nagoya City University Graduate School of Medical Sciences, 1-Kawasumi, Mizuho-Cho, Mizuho-Ku, Nagoya 467-8601, JapanTel +81 52-8538251Fax +81 52-8419490Email yoshio.hirano@gmail.comPurpose: To classify microaneurysms (MAs) and investigate the relationships with retinal edema in eyes with branch retinal vein occlusion (BRVO).Study Design: Retrospective, observational, consecutive case series.Methods: Eyes with MAs due to BRVO that underwent optical coherence tomography angiography (OCTA) were enrolled. MAs on OCTA images were morphologically classified into six types: focal bulge, saccular, fusiform, mixed (saccular/fusiform), pedunculated, and irregular. The frequency, size, location, and relationships with retinal edema also were investigated.Results: Twenty-four eyes of 23 patients (12 men, 11 women; mean age, 68.0 years) were enrolled. A total of 244 MAs were detected on the OCTA images. The focal bulge and saccular types accounted for over 70% of all MAs. Smaller MAs such as the focal bulge or saccular type also were detected both at the edge of the nonperfused areas (NPAs) and in collateral vessels. In contrast, larger MAs such as the pedunculated or irregular types tended to form at the edges of the NPAs. Older age, the presence of MAs in the collateral vessels, and the absence of pedunculated type were independent predictive factors for retinal edema but not the MA size, or presence in the retinal deep capillary plexus. After treatment, the mean retinal thickness decreased significantly, but the mean MA size remained unchanged.Conclusion: OCTA enables morphologic classification, three-dimensional analysis, and investigation of the longitudinal changes of MAs with noninvasive volumetric quantification, leading to a better understanding of the pathology of MAs in eyes with BRVO.Keywords: microaneurysm, morphology, macular edema, optical coherence tomography angiography, branch retinal vein occlusion

Seung Joon Lee,1,2 In Choel Shin,1,2 Il Won Jeong,1,2 Chang Wook Choi,1,2 Yun Sik Yang1,2 1Department of Ophthalmology, Wonkwang University College of Medicine, Iksan, Korea; 2Institute of Wonkwang Medical Science, Wonkwang University, Iksan, KoreaCorrespondence: Yun Sik YangDepartment of Ophthalmology, Wonkwang University Hospital, #895 Muwang-Ro, Iksan, 54538, KoreaTel +82 63 859 1370Fax +82 63 855 1801Email ysyang@wonkwang.ac.krPurpose: To analyze the effects on microaneurysm (MA) and perifoveal perfusion in nonproliferative diabetic retinopathy (NPDR) patients with macular edema (ME) after early intensive treatment using intravitreal ranibizumab (IVR) injections.Patients and Methods: Prospectively, 25 eyes of 25 type 2 diabetes mellitus patients with ME were included between August 2016 and February 2019. For 6 months, patients were administered 0.5-mg IVR injections monthly. Ocular evaluation, including best-corrected visual acuity (BCVA; using the Early Treatment Diabetic Retinopathy Study chart), central retinal thickness (CRT; using optical coherence tomography), fundus photography, and fluorescein angiography, was performed for all participants. Results obtained at baseline were compared to those observed after 6 months.Results: Mean BCVA increased significantly from 67.6± 3.29 letters at baseline to 76.36± 1.61 letters after 6 months (P=0.002) of IVR therapy. CRT decreased significantly from 479.12± 16.66 μm at baseline to 369.12± 13.02 μm at 6 months. Similarly, the total number of MAs decreased significantly from 5.68± 3.41 to 1.60± 1.73 (P< 0.0001). MA turnover, calculated by adding the MA formation rate to the MA disappearance rate (both calculated as MA number/month) also decreased significantly from 6.88± 3.83 to 1.92± 1.75 after treatment (P< 0.0001). Perifoveal non-perfused area decreased from 2.517± 0.456 mm2 at baseline to 2.495± 0.293 mm2 at 6 months, but the results were not statistically significant (P=0.954).Conclusion: Treatment with early intensive IVR therapy in NPDR patients with ME not only improved BCVA and CRT but also decreased MA turnover. However, in the study period of 6 months, IVR therapy did not show significant improvement in perifoveal non-perfused area.Keywords: nonproliferative diabetic retinopathy, macular edema, ranibizumab, early intensive treatment, microaneurysm

Predicting the presence of Microaneurysms in the fundus images and the identification of diabetic retinopathy in early-stage has always been a major challenge for decades. Diabetic Retinopathy (DR) is affected by prolonged high blood glucose level which leads to microvascular complications and irreversible vision loss. Microaneurysms formation and macular edema in the retinal is the initial sign of DR and diagnosis at the right time can reduce the risk of non proliferated diabetic retinopathy. The rapid improvement of deep learning makes it gradually become an efficient technique to provide an interesting solution for medical image analysis problems. The proposed system analysis the presence of microaneurysm in fundus image using convolutional neural network algorithms that embeds deep learning as a core component accelerated with GPU(Graphics Processing Unit) which will perform medical image detection and segmentation with high-performance and low-latency inference. The semantic segmentation algorithm is utilized to classify the fundus picture as normal or infected. Semantic segmentation divides the image pixels based on their common semantic to identify the feature of microaneurysm. This provides an automated system that will assist ophthalmologists to grade the fundus images as early NPDR, moderate NPDR, and severe NPDR. The Prognosis of Microaneurysm and early diagnosis system for non - proliferative diabetic retinopathy system has been proposed that is capable to train effectively a deep convolution neural network for semantic segmentation of fundus images which can increase the efficiency and accuracy of NPDR (non proliferated diabetic retinopathy) prediction.

Background: Nontraumatic acute subdural hematoma (ASDH) may be caused by rupture of a microaneurysm of a cortical artery. In some cases, microaneurysms may have been caused by earlier trauma. Although it is difficult to detect microaneurysms on contrast-enhanced computed tomography (CT) angiography or digital subtraction angiography, it may be suspected based on the plain CT scan results and the clinical course. Case Description: We experienced three cases presumed to be ASDH due to rupture of a microaneurysm. Plain CT scan showed that the midline shift was smaller than the hematoma thickness, and we judged from the clinical course that there was no trauma immediately before the onset. All three patients had decreased consciousness after arrival and underwent craniotomy for hematoma removal. The source of hemorrhage was in the distal part of the cortical artery, and a microaneurysm was found. In one case, histopathological examination was performed, and traumatic pseudoaneurysm was diagnosed. The postoperative course was good in all three cases. Conclusion: If nontraumatic ASDH is suspected, the source of hemorrhage may be located more distally to the middle cerebral artery than in traumatic ASDH; hence, extensive craniotomy is required to search for the location of hemorrhage. [ABSTRACT FROM AUTHOR]

Background: Basilar artery perforator aneurysms (BAPAs) are rare. Traditional surgical clipping and endovascular coiling have proven to be challenging. We present three patients treated with endovascular electrothrombosis and describe the characteristics of this new approach. Methods: Three patients presented with subarachnoid hemorrhages (SAHs). Cerebral angiography identified BAPAs. Endovascular electrothrombosis was performed after obtaining informed consent. We placed the microwire into the sac of the aneurysms through the microcatheter and connected its proximal tip to the Solitaire stent detachment system. Electrothrombosis was conducted using 1.0 mA current. Results: Two aneurysms were successfully occluded without treatment-related complication. The third one failed and converted to endovascular coiling using a 1.3-F microcatheter. The patient suffered brainstem infarction and finally died of severe SAH. At follow-up, the two patients were neurologically intact and angiography showed total occlusion of both aneurysms. Conclusion: Endovascular electrothrombosis might be a potential alternative to traditional treatment for BAPAs. Close follow-up with caution should be mandatory. More research is needed to confirm its safety and efficacy. [ABSTRACT FROM AUTHOR]

In a hypertensive hemorrhagic focus of the basal ganglia, the culprit arteries have been reported to be associated with dissecting lesions, whose topographical relationship to the rupture sites remains to be clarified. Herein we describe multiple dissecting lesions in the culprit artery of hypertensive hemorrhage of the basal ganglia. A 1.0 × 0.8 × 0.8 cm‐sized bleeding globe was confirmed at a left lenticulostriate artery and histologically analyzed by serial sectioning. Three independent dissecting lesions were identified in the culprit artery. They were situated near the bifurcations, ranging from 240 to 3200 μm in length. The dissections mainly occurred between the intima and media with disruption of the internal elastic lamina (IEL), forming a fresh thrombus within the false lumen. Two rupture sites causing the cerebral hematoma were confirmed away from the dissecting lesions. One was situated close but not adjacent to the longest dissecting lesion; the other, measuring approximately 150 μm in diameter, was adjacent to the bifurcation of an artery. The histopathological findings suggest that the dissecting lesion resulted from medial detachment following IEL disruption in the process of arterial rupture of the culprit artery. We conclude that this was a secondary manifestation during the rupture rather than a cause of the arterial rupture. [ABSTRACT FROM AUTHOR]

Background and Objectives: The presence of refractory cases resistant to anti-vascular endothelial growth factor (VEGF) therapy for diabetic macular edema (DME) is a problem in clinical practice. This study aimed to explore the less responsive area of optical coherence tomography (OCT) 3D map the characteristics of naïve DME cases after their first anti-VEGF. Materials and Methods: In 46 patients with DME who received an intravitreal injection of anti-VEGF agents, retinal thickness in 100 sections of the macular area was measured by 3D-mapping mode using OCT before and 1 month after injection. The density of the microaneurysm (MA) was calculated using merged images of the OCT map and fluorescein angiography. Results: One month after injection, the central retinal thickness significantly decreased (p < 0.0001). In severe edema (retinal thickness more than 500 µm), the area percentages with a reduction rate of the retinal thickness greater than 30% and less than 5% were 6.4 ± 6.6% and 10.1 ± 4.6%, respectively. The reduction rate of the retinal thickness varied from section to section. The mutual distance between the areas of maximum thickness before and after the injection averaged 1.22 ± 0.62 mm apart. The reduction rate of retinal thickness in the thickest region before injection was significantly higher (p = 0.02), and that in the thickest region after injection was lower (p = 0.001) than in the other regions. MA density in the residual edema was significantly higher than in the edema-absorbed area (p = 0.03). Conclusion: DME has areas that show low response to the reduction in retinal thickness with anti-VEGF therapy. A high density of MA may be associated with this pathogenesis.

Purpose: To characterize the progression in retinopathy severity of different phenotypes of mild nonproliferative diabetic retinopathy (NPDR) in patients with type 2 diabetes. Design and methods: Patients with type 2 diabetes and mild NPDR (ETDRS 20 or 35) were followed in a 5-year longitudinal study. Examinations, including color fundus photography (CFP) and optical coherence tomography (OCT and OCTA), were performed at baseline, 6 months and then annually. Phenotype classification was performed based on microaneurysm turnover (MAT, on CFP) and central retinal thickness (CRT, on OCT). Phenotype A is characterized by low MAT (< 6) and normal CRT; Phenotype B by low MAT (< 6) and increased CRT; and Phenotype C by higher MAT (≥ 6) with or without increased CRT. ETDRS grading of seven fields CFP was performed at the initial and last visits. Results: Analysis of ETDRS grade step changes showed significant differences in diabetic retinopathy (DR) progression between the different phenotypes (p < 0.001). Of the 66 participants with phenotype A only 2 eyes (3%) presented 2-or-more-step worsening. None of the 50 participants characterized as phenotype B developed 2-step worsening, whereas 13 eyes (23.2%) characterized as phenotype C had 2-or-more-steps worsening. Phenotype C presents the higher risk for 2-or-more step worsening (OR: 15.94 95% CI: 3.45–73.71; p < 0.001) and higher sensitivity, correctly identifying 86.7% of cases at risk (AUC: 0.84 95% CI: 0.72–0.96; p < 0.001). Diabetic retinopathy severity progression was associated with HbA1c (p = 0.019), LDL levels (p = 0.043), and ocular factors as MAT (p = 0.010), MA formation rate (p = 0.014) and MA disappearance rate (p = 0.005). Capillary closure at 5-year follow-up, identified by lower vessel density (VD) on OCTA, was also associated with diabetic DR severity progression (p = 0.035). Conclusions: Different DR phenotypes in type 2 diabetes show different risks of retinopathy progression. Phenotype C is associated with increased HbA1c values and presents a higher risk of a 2-or-more-step worsening of the ETDRS severity score. [ABSTRACT FROM AUTHOR]