Background: Diabetic retinopathy (DR) is a retinopathy resulting from diabetes mellitus (DM) which was classified into non-proliferative DR (NPDR) and proliferative DR (PDR). Without an early screening and effective diagnosis, patients with PDR will develop serious complications. Therefore, we sought to identify special serum microRNAs (miRNAs) that can serve as a novel non-invasive screening signature of PDR and test its specificity and sensitivity in the early diagnosis of PDR. Methods: In total, we obtained serum samples from 90 PDR cases, 90 matched NPDR patients and 20 controls. An initial screening of miRNA expression was performed through TaqMan Low Density Array (TLDA). The candidate miRNAs were validated by individual reverse transcription quantitative real-time PCR (RT-qPCR) arranged in an initial and a two-stage validation sets. Moreover, additional double-blind testing was performed in 20 patients clinically suspected of having DR to evaluate the diagnostic value and accuracy of the serum miRNA profiling system in predicting PDR. Results: Three miRNAs were significantly increased in patients with PDR compared with NPDR after the multiple stages. The areas under the receiver operating characteristic (ROC) curves of the validated three-serum miRNAs signature were 0.830, 0.803 and 0.873 in the initial and two validation sets, respectively. Combination of miR-21, miR-181c, and miR-1179 possessed a moderate ability to discrimination between PDR and NPDR with an area under ROC value of 0.89. The accuracy rate of the three-miRNA profile as PDR signature was 82.6%. Conclusions: These data provide evidence that serum miRNAs have the potential to be sensitive, cost-effective biomarkers for the early detection of PDR. These biomarkers could serve as a dynamic monitoring factor for detecting the progression of PDR from NPDR.

A substantial number of potential new genes and new mutations associated with HRDs remain to be discovered. Identification of the novel HRDs-causing mutations in our study not only provides a better understanding of genotype-phenotype relationships in these diseases, but also demonstrates that the approach described herein is an effective method for large scale mutation detection among diverse and complicated HRDs cases.

For years, branch retinal vein occlusion is still a controversial disease in many aspects. An increasing amount of data is available regarding classification, pathogenesis, risk factors, natural history, and therapy of branch retinal vein occlusion. Some of the conclusions may even change our impression of branch retinal vein occlusion. It will be beneficial for our doctors to get a deeper understanding of this disease and improve the treatment skills. The aims of this review is to collect the information above and report new ideas especially from the past a few years.

Optical coherence tomography angiography (OCTA) is a novel noninvasive imaging modality that allows micron-level resolution to visualize the retinal microvasculature. The retinal vessel segmentation in OCTA images is still an open problem, and especially the thin and dense structure of the capillary plexus is an important challenge of this problem. In this work, we propose a novel image magnification network (IMN) for vessel segmentation in OCTA images. Contrary to the U-Net structure with a down-sampling encoder and up-sampling decoder, the proposed IMN adopts the design of up-sampling encoding and then down-sampling decoding. This design is to capture more image details and reduce the omission of thin-and-small structures. The experimental results on three open OCTA datasets show that the proposed IMN with an average dice score of 90.2% achieves the best performance in vessel segmentation of OCTA images. Besides, we also demonstrate the superior performance of IMN in crossfield image vessel segmentation and vessel skeleton extraction.

Purpose. To describe both the functional and pathological alternations in neurosensory retina in a murine model of spontaneous type 2 diabetes (db/db mouse). Methods. db/db (BKS/DB−/−) mice and heterozygous littermates (as control group) at various ages (12, 16, 20, 24, and 28 weeks) were inspected with pattern electroretinogram (PERG), fundus fluorescein angiography (FFA), and optical coherence tomography (OCT). Histological markers of neuroinflammation (IBA-1 and F4/80) were evaluated by immunohistochemistry. In addition, levels of retinal ganglion cell death were measured by terminal dUTP nick-end labeling (TUNEL). Results. Significant alternations of PERG responses and increased retinal ganglion cells (RGCs) apoptosis were observed in diabetic db/db mice for 20-week period when compared with control group. IBA-1 and F4/80 expression in microglia/macrophages became evidently for 24-week period, thus supporting the PERG findings. Furthermore, obvious thinning of nasal and dorsal retina in 28-week-old db/db mice was also revealed by OCT. No visible retinal microvascular changes were detected by FFA throughout the experiments on db/db mice. Conclusions. Diabetic retina underwent neurodegenerative changes in db/db mice, which happened at retinal ganglion cell layer and inner nuclear layer. But there was no obvious abnormality in retinal vasculature on db/db mice.

Pathologic microvasculature plays a crucial role in innumerable diseases causing death and major organ impairment. A major clinical challenge is the development of selective therapies to remove these diseased microvessels without damaging surrounding tissue. This report describes our development of novel photo-mediated ultrasound therapy (PUT) technology for precisely removing choroidal blood vessels in the eye. PUT selectively removes microvessels by concurrently applying nanosecond laser pulses with ultrasound bursts. In PUT experiments on rabbit eyes in vivo, we applied 55–75 mJ/cm2 of light fluence at the retinochoroidal surface at 532-nm and 0.5 MPa of ultrasound pressure at 0.5 MHz. PUT resulted in significantly reduced blood perfusion in the choroidal layer which persisted to four weeks without causing collateral tissue damage, demonstrating that PUT is capable of removing choroidal microvasculature safely and effectively. With its unique advantages, PUT holds potential for the clinical management of eye diseases associated with microvessels and neovascularization.

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The choroid is an important structure of the eye and plays a vital role in the pathology of retinal diseases. This paper presents an automated choroid segmentation method for high-definition optical coherence tomography (HD-OCT) images, including Bruch's membrane (BM) segmentation and choroidal-scleral interface (CSI) segmentation. An improved retinal nerve fiber layer (RNFL) complex removal algorithm is presented to segment BM by considering the structure characteristics of retinal layers. By analyzing the characteristics of CSI boundaries, we present a novel algorithm to generate a gradual intensity distance image. Then an improved 2-D graph search method with curve smooth constraints is used to obtain the CSI segmentation. Experimental results with 212 HD-OCT images from 110 eyes in 66 patients demonstrate that the proposed method can achieve high segmentation accuracy. The mean choroid thickness difference and overlap ratio between our proposed method and outlines drawn by experts was 6.72µm and 85.04%, respectively.