Retina Of Human Eye Research Articles

Uniform-sampling foveated Fourier single-pixel imaging

Inspired by the retina of human eye, foveated imaging is an effective way to achieve high imaging quality and high imaging efficiency. However, with an inherent property of nonuniformity, advantages of foveated imaging cannot be played well due to the confliction with many theories having uniform properties. Thus, an innovative concept “uniform-sampling foveated imaging” is proposed to break the barrier of foveated imaging and uniform imaging. In this work, the concept is used as a uniform-sampling foveated Fourier single-pixel imaging (UFFSI) to achieve high imaging quality and high imaging efficiency of single-pixel imaging (SPI). First, by flexibly using the proposed three kinds of foveated pattern structures of foveated SPI, namely, “circular structure” via log-polar transformation, “rectangular structure” via log-rectilinear transformation and “rotating-rectangle structure” via log-rectilinear-rotation transformation, the total data number is reduced radically by the data redundancy reduction only requiring high resolution (HR) on regions of interest (ROIs). Next, by a nonuniform weight distribution processing based on the innovative concept of “uniform-sampling foveated imaging”, nonuniform sampling is transformed into uniform sampling to obtain the same uniform optical power as the uniform HR FSI, thus, sparse spectrum property and fast Fourier transform of FSI are used accurately and directly to obtain high imaging quality with further reduced measurements and fast reconstruction. Experimentally, in a large-scale scene, at an ultralow sampling ratio of 0.78 % referring to uniform HR FSI with 1024 × 768 pixels, by using UFFSI with 89 % reduction of data redundancy, ROI has a significantly better imaging quality with around 3.3times reduction in reconstruction time. We hope this work can provide a breakthrough point for future foveated imaging and real-time SPI in real life.

Bio-inspired “Self-denoising” capability of 2D materials incorporated optoelectronic synaptic array

In in-sensor image preprocessing, the sensed image undergoes low level processing like denoising at the sensor end, similar to the retina of human eye. Optoelectronic synapse devices are potential contenders for this purpose, and subsequent applications in artificial neural networks (ANNs). The optoelectronic synapses can offer image pre-processing functionalities at the pixel itself—termed as in-pixel computing. Denoising is an important problem in image preprocessing and several approaches have been used to denoise the input images. While most of those approaches require external circuitry, others are efficient only when the noisy pixels have significantly lower intensity compared to the actual pattern pixels. In this work, we present the innate ability of an optoelectronic synapse array to perform denoising at the pixel itself once it is trained to memorize an image. The synapses consist of phototransistors with bilayer MoS2 channel and p-Si/PtTe2 buried gate electrode. Our 7 × 7 array shows excellent robustness to noise due to the interplay between long-term potentiation and short-term potentiation. This bio-inspired strategy enables denoising of noise with higher intensity than the memorized pattern, without the use of any external circuitry. Specifically, due to the ability of these synapses to respond distinctively to wavelengths from 300 nm in ultraviolet to 2 µm in infrared, the pixel array also denoises mixed-color interferences. The “self-denoising” capability of such an artificial visual array has the capacity to eliminate the need for raw data transmission and thus, reduce subsequent image processing steps for supervised learning.

Nanoparticles of Push-Pull Triphenylamine-Based Molecules for Light-Controlled Stimulation of Neuronal Activity.

Organic semiconductor materials with a unique set of properties are very attractive for interfacing biological objects and can be used for noninvasive therapy or detection of biological signals. Here, we describe the synthesis and investigation of a novel series of organic push-pull conjugated molecules with the star-shaped architecture, consisting of triphenylamine as a branching electron donor core linked through the thiophene π-spacer to electron-withdrawing alkyl-dicyanovinyl groups. The molecules could form stable aqueous dispersions of nanoparticles (NPs) without the addition of any surfactants or amphiphilic polymer matrixes with the average size distribution varying from 40 to 120 nm and absorption spectra very similar to those of human eye retina pigments such as rods and green cones. Variation of the terminal alkyl chain length of the molecules forming NPs from 1 to 12 carbon atoms was found to be an efficient tool to modulate their lipophilic and biological properties. Possibilities of using the NPs as light nanoactuators in biological systems or as artificial pigments for therapy of degenerative retinal diseases were studied both on the model planar bilayer lipid membranes and on the rat cortical neurons. In the planar bilayer system, the photodynamic activity of these NPs led to photoinactivation of ion channels formed by pentadecapeptide gramicidin A. Treatment of rat cortical neurons with the NPs caused depolarization of cell membranes upon light irradiation, which could also be due to the photodynamic activity of the NPs. The results of the work gave more insight into the mechanisms of light-controlled stimulation of neuronal activity and for the first time showed that fine-tuning of the lipophilic affinity of NPs based on organic conjugated molecules is of high importance for creating a bioelectronic interface for biomedical applications.

Memory effect and coexistence of negative and positive photoconductivity in black phosphorus field effect transistor for neuromorphic vision sensors.

Black phosphorus (BP) field-effect transistors with ultrathin channels exhibit unipolar p-type electrical conduction over a wide range of temperatures and pressures. Herein, we study a device that exhibits mobility up to 100 cm2 V-1 s-1 and a memory window up to 1.3 μA. Exposure to a supercontinuum white light source reveals that negative photoconductivity (NPC) and positive photoconductivity (PPC) coexist in the same device. Such behavior is attributed to the chemisorbed O2 molecules, with a minor role of physisorbed H2O molecules. The coexistence of NPC and PPC can be exploited in neuromorphic vision sensors, requiring the human eye retina to process the optical signals through alerting and protection (NPC), adaptation (PPC), followed by imaging and processing. Our results open new avenues for the use of BP and other two-dimentional (2D) semiconducting materials in transistors, memories, and neuromorphic vision sensors for advanced applications in robotics, self-driving cars, etc.

Fluidic Simulation and Optimization of Microchannels for Retinal Vein Occlusion (RVO) by Using Fuzzy Technique

A microelectromechanical system (MEMS) is a diminutive machine having electronic and mechanical components with a size ranging from 20 µm-1 mm. In this present-day world, MEMS fabrication techniques have remodeled the conventional approaches towards system fabrication. Microfluidics is an eminent domain of MEMS in which small volumes of fluids are disciplined in micro-channels having dimensions in the submillimeter to achieve the desired outputs. Microfluidics have revolutionized the realm of compact system fabrication through preeminent inventions like lab-on-a-chip technology. Microchannels of various architectures are fabricated to employ microfluidic systems depending upon the required function of the device. In ophthalmology, Retinal Vein Occlusion (RVO) is an ailment in which small veins that take away blood from the human eye's retina are blocked or fissured, causing vision loss. Therefore, in this study, four micro-channels with different architectures, namely, sinusoidal, U-shaped, spiral, and curvilinear, were simulated by using the fuzzy technique to investigate the optimization of fluids for the implantation process to fix the RVO elixir. The two most critical parameters in retinal vein flow rate and velocity were taken at the output for optimization. Hence, fuzzy fluidic simulation revealed that curvilinear micro-channels were the best fit for biomedical implantation to treat RVO malady.

A non-iterative foveated single-pixel imaging using fast transformation algorithm

Inspired by the human eye retina, foveated single-pixel imaging employs an iterative algorithm, which, unfortunately, poses a challenge for real-time imaging due to its time-consuming nature. To address this issue, we present a non-iterative foveated single-pixel imaging method based on a computationally fast algorithm, reducing time consumption by five orders of magnitude. The fast algorithmic transform facilitates the acquisition of foveated reconstructions. In addition to mimicking human saccadic eye movements, the foveated strategy adapts to motion tracking through the foveal gaze control method. During high-resolution imaging in the fovea area, the maximum sensing area expands 3.14 times, similar to human vision. The proposed retina-like single-pixel imaging has great potential in future applications with the advantages of avoiding complex optics design, low time consumption, and wider vision field.

Bone Morphogenetic Protein-4 Impairs Retinal Endothelial Cell Barrier, a Potential Role in Diabetic Retinopathy.

Bone Morphogenetic Protein 4 (BMP4) is a secreted growth factor of the Transforming Growth Factor beta (TGFβ) superfamily. The goal of this study was to test whether BMP4 contributes to the pathogenesis of diabetic retinopathy (DR). Immunofluorescence of BMP4 and the vascular marker isolectin-B4 was conducted on retinal sections of diabetic and non-diabetic human and experimental mice. We used Akita mice as a model for type-1 diabetes. Proteins were extracted from the retina of postmortem human eyes and 6-month diabetic Akita mice and age-matched control. BMP4 levels were measured by Western blot (WB). Human retinal endothelial cells (HRECs) were used as an in vitro model. HRECs were treated with BMP4 (50 ng/mL) for 48 h. The levels of phospho-smad 1/5/9 and phospho-p38 were measured by WB. BMP4-treated and control HRECs were also immunostained with anti-Zo-1. We also used electric cell-substrate impedance sensing (ECIS) to calculate the transcellular electrical resistance (TER) under BMP4 treatment in the presence and absence of noggin (200 ng/mL), LDN193189 (200 nM), LDN212854 (200 nM) or inhibitors of vascular endothelial growth factor receptor 2 (VEGFR2; SU5416, 10 μM), p38 (SB202190, 10 μM), ERK (U0126, 10 μM) and ER stress (Phenylbutyric acid or PBA, 30 μmol/L). The impact of BMP4 on matrix metalloproteinases (MMP2 and MMP9) was also evaluated using specific ELISA kits. Immunofluorescence of human and mouse eyes showed increased BMP4 immunoreactivity, mainly localized in the retinal vessels of diabetic humans and mice compared to the control. Western blots of retinal proteins showed a significant increase in BMP4 expression in diabetic humans and mice compared to the control groups (p < 0.05). HRECs treated with BMP4 showed a marked increase in phospho-smad 1/5/9 (p = 0.039) and phospho-p38 (p = 0.013). Immunofluorescence of Zo-1 showed that BMP4-treated cells exhibited significant barrier disruption. ECIS also showed a marked decrease in TER of HRECs by BMP4 treatment compared to vehicle-treated HRECs (p < 0.001). Noggin, LDN193189, LDN212854, and inhibitors of p38 and VEGFR2 significantly mitigated the effects of BMP4 on the TER of HRECs. Our finding provides important insights regarding the role of BMP4 as a potential player in retinal endothelial cell dysfunction in diabetic retinopathy and could be a novel target to preserve the blood-retinal barrier during diabetes.

Granzyme B Contributes to Choroidal Neovascularization and Age-Related Macular Degeneration Through Proteolysis of Thrombospondin-1

Age-related macular degeneration (AMD) is a leading cause of irreversible central vision loss in the elderly. The pathology of neovascular age-related macular degeneration (nAMD), also known as wet AMD, is associated with an abnormal blood vessel growth in the eye and involves an imbalance of proangiogenic and antiangiogenic factors. Thrombospondin (TSP)-1 and TSP-2 are endogenous matricellular proteins that inhibit angiogenesis. TSP-1 is significantly diminished in eyes with AMD, although the mechanisms involved in its reduction are unknown. Granzyme B (GzmB) is a serine protease with an increased extracellular activity in the outer retina and choroid of human eyes with nAMD-related choroidal neovascularization (CNV). This study investigated whether TSP-1 and TSP-2 are GzmB substrates using in silico and cell-free cleavage assays and explored the relationship between GzmB and TSP-1 in human eyes with nAMD-related CNV and the effect of GzmB on TSP-1 in retinal pigment epithelial culture and an explant choroid sprouting assay (CSA). In this study, TSP-1 and TSP-2 were identified as GzmB substrates. Cell-free cleavage assays substantiated the GzmB proteolysis of TSP-1 and TSP-2 by showing dose-dependent and time-dependent cleavage products. TSP-1 and TSP-2 proteolysis were hindered by the inhibition of GzmB. In the retinal pigment epithelium and choroid of human eyes with CNV, we observed a significant inverse correlation between TSP-1 and GzmB, as indicated by lower TSP-1 and higher GzmB immunoreactivity. In CSA, the vascular sprouting area increased significantly with GzmB treatment and reduced significantly with TSP-1 treatment. Western blot showed significantly reduced expression of TSP-1 in GzmB-treated retinal pigment epithelial cell culture and CSA supernatant compared with that in controls. Together, our findings suggest that the proteolysis of antiangiogenic factors such as TSP-1 by extracellular GzmB might represent a mechanism through which GzmB may contribute to nAMD-related CNV. Future studies are needed to investigate whether pharmacologic inhibition of extracellular GzmB can mitigate nAMD-related CNV by preserving intact TSP-1.

Adenosine Receptors Expression in Human Retina and Choroid with Age-related Macular Degeneration.

Adenosine signaling modulates ocular inflammatory processes, and its antagonism mitigates neovascularization in both newborns and preclinical models of ocular neovascularization including age-related macular degeneration (AMD). The adenosine receptor expression patterns have not been well characterized in the human retina and choroid. Here we examined the expression of adenosine receptor subtypes within the retina and choroid of human donor eyes with and without AMD. Antibodies specifically targeting adenosine receptor subtypes A1, A2A, A2B, and A3 were used to assess their expression patterns. Quantitative real-time PCR analysis was used to confirm gene expression of these receptors within the normal human retina and choroid. We found that all four receptor subtypes were expressed in several layers of the retina, and within the retinal pigment epithelium and choroid. The expression of A1 receptors was more prominent in the inner and outer plexiform layers, where microglia normally reside, and supported by RNA expression in the retina. A2A and A2B showed similar expression patterns with prominent expression in the vasculature and retinal pigment epithelium. No dramatic differences in expression of these receptors were observed in eyes from patients with dry or wet AMD compared to control, with the exception A3 receptors. Eyes with dry AMD lost expression of A3 in the photoreceptor outer segments compared with eyes from control or wet AMD. The ocular presence of adenosine receptors is consistent with their proposed role in modulation of inflammation in both the retina and choroid, and their potential targeting for AMD treatment.

Retina Disorders Classification via OCT Scan: A Comparative Study between Self-Supervised Learning and Transfer Learning

Retina disorders are among the common types of eye disease that occur due to several reasons such as aging, diabetes and premature born. Besides, Optical Coherence Tomography (OCT) is a medical imaging method that serves as a vehicle for capturing volumetric scans of the human eye retina for diagnoses purposes. This research compared two pretraining approaches including Self-Supervised Learning (SSL) and Transfer Learning (TL) to train ResNet34 neural architecture aiming at building computer aided diagnoses tool for retina disorders recognition. In addition, the research methodology employs convolutional auto-encoder model as a generative SSL pretraining method. The research efforts are implemented on a dataset that contains 109,309 retina OCT images with three medical conditions including Choroidal Neovascularization (CNV), Diabetic Macular Edema (DME), DRUSEN as well as NORMAL condition. The research outcomes showed better performance in terms of overall accuracy, sensitivity and specificity, namely, 95.2%, 95.2% and 98.4% respectively for SSL ResNet34 in comparison to scores of 90.7%, 90.7% and 96.9% respectively for TL ResNet34. In addition, SSL pretraining approach showed significant reduction in the number of epochs required for training in comparison to both TL pretraining as well as the previous research performed on the same dataset with comparable performance.

TIPARP is involved in the regulation of intraocular pressure

Elevated intraocular pressure (IOP) is the major risk factor for glaucoma. The molecular mechanism of elevated IOP is unclear, which impedes glaucoma therapy. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-inducible Poly-ADP-ribose Polymerase (TIPARP), a member of the PARP family, catalyses mono-ADP-ribosylation. Here we showed that TIPARP was widely expressed in the cornea, trabecular meshwork, iris, retina, optic nerve, sclera, and choroid of human eyes. The expression of TIPARP was significantly upregulated in the blood and trabecular meshwork of patients with primary open angle glaucoma compared with that of healthy controls. Transcriptome analysis revealed that the expression of genes related to extracellular matrix deposition and cell adhesion was decreased in TIPARP-upregulated human trabecular meshwork (HTM) cells. Moreover, western blot analysis showed that collagen types I and IV, fibronectin, and α-SMA were increased in TIPARP-downregulated or TIPARP-inhibited HTM cells. In addition, cross-linked actin networks were produced, and vinculin was upregulated in these cells. Subconjunctival injection of the TIPARP inhibitor RBN-2397 increased the IOP in Sprague–Dawley rats. Therefore, we identified TIPARP as a regulator of IOP through modulation of extracellular matrix and cell cytoskeleton proteins in HTM cells. These results indicate that TIPARP is a potential therapeutic target for ocular hypertension and glaucoma.

Mimicking Melanopsin Behavior with Integrated Photoregulated Memory

AbstractMelanopsin is an essential element in the human eye, sensing optical light, indeed beyond the function of rods and cones, and contributing largely to non‐image‐forming functions like learning behavior, emotions, and maintaining sun cycle. Mimicking melanopsin behavior using an optoelectronic device could be an essential step toward the advancement of future technologies, including data storage applications and artificial vision. This research proposes and illustrates the mimicking of the primitive functions of melanopsin in a manner very similar to the human eye retina by using an integrated Schottky photodetector and an HfO2‐based memory device. Particularly, current–voltage curves show nominal hysteresis loop opening under dark conditions, whereas stable analog hysteresis loops form with light illumination, which is regulated progressively by increasing the intensity. Based on photoconductive atomic force microscopy and charge transport measurements, the charge trapping/detrapping is estimated to be associated with the light‐regulated hysteresis loop opening. Specifically, versatile synaptic functions are stimulated artificially with an optical pulse, which is sustained over a long period of time even after removing the light, indeed very similar to melanopsin behavior. The optically regulated properties described herein pave the way for the development of artificial optoelectronic melanopsin, artificial biological electronics, soft robotics, and data storage applications.

On the Correspondence between the Spectral Sensitivity Characteristics of Human Eye Retina Photo-Receivers and the Frequencies of the Universal Period-Tripling System

The article is devoted to the discussion of the evolutionary adjustment of the photodetectors of the human retina to the frequencies of the UPTS (the so-called universal period-tripling system). This is a new scientific direction in the study of complex systems. The article invites lighting engineers who study the issues of visual perception to get acquainted with the phenomenon of UPTS. To date, an experimental research material has been accumulated and sufficient theoretical grounds have been obtained for the formulation of the assumption that the UPTS and its main parameter Тk, m are manifested in almost all time scales. The values of Тk, m are described with great accuracy by means of the empirical Puetz’s formula. In human vision, UPTS manifests itself in the form of nine periods of Тk, m, corresponding to the cases of m = –11, –8, –5, –3, 0, 3, 5, 8, and 11, where the five central ones dominate –5, –3, 0, 3, and 5, corresponding to the rods, as well as the B- and R-cones. Some questions remain about the G-cones and the ipRGC cells that respond to the extreme, “weakened” values of the index m = –11, –8, 8, and 11. The determination of the proposed calculated values of the wavelengths of light corresponding to the maximum spectral sensitivity of retinal photodetectors is important for specialists in the field of visual perception, medicine, optics, as well as for applications in a number of technical applications.

Retina-like Imaging and Its Applications: A Brief Review

The properties of the human eye retina, including space-variant resolution and gaze characters, provide many advantages for numerous applications that simultaneously require a large field of view, high resolution, and real-time performance. Therefore, retina-like mechanisms and sensors have received considerable attention in recent years. This paper provides a review of state-of-the-art retina-like imaging techniques and applications. First, we introduce the principle and implementing methods, including software and hardware, and describe the comparisons between them. Then, we present typical applications combined with retina-like imaging, including three-dimensional acquisition and reconstruction, target tracking, deep learning, and ghost imaging. Finally, the challenges and outlook are discussed to further study for practical use. The results are beneficial for better understanding retina-like imaging.

Retinal Based Pathology Analysis Using Deep Learning Approaches

: Deep learning is an excellent approach to biomedical image segmentation tasks that help to identify and quantify patterns. Segmentation of biomedical images typically involves partitioning an image into multiple regions representing anatomical objects of interest. Biomedical image processing is a very broad field. Here, input is given as an image to extract features from an image to detect diseases. Unsupervised learning technique is used because it enables the model to uncover trends and facts that were previously undetected on its own. Human eye retina can provide valuable information about human health. The condition of the retinal vessels has been found to be a good indicator of overall health. For the prediction of retinal disease, it is classified as a retinal background, retinal vessels and optic disc. The disease can be predicted by this classification using the Singular Spectrum Analysis, Deep Neural Network, KNN Classifier and Eclipse Fitting algorithm. Singular Spectrum analysis was carried out to predict cross-section profiles for the detection of micro aneurysms. Diabetic diseases are classified under the KNN classification. Deep Neural Network algorithm is used for predicting cardiovascular disease and other disease such as glaucoma, stroke. Using the Eclipse Fitting algorithm, the optical disc and cup pixels are segmented to check whether or not a person's health is normal.

Digital holographic microscope for human eye retinal structures recording in vivo.

We introduce the digital holographic microscope for recording in vivo human eye retinal structures. Current eye imaging technologies cannot provide images with resolutions better than 1 µm within depths of a few hundred micrometers. This can be improved with digital holography, in which a hologram of the eye captured with digital camera contains information about structures over the full depth of the eye. This information can be reconstructed either optically or numerically. Our hologram recording scheme utilizes working principles of the off-axis digital holographic microscope, designed for reflective micro-object investigation. The eye cornea and lens form the microscope objective. We can record in vivo digital holograms of the human eye retina with resolution after reconstruction of at least 1.3 micrometer.

Quantum antenna operating at 430 to 750 THz band, inspired through human eye

Optical antenna is coming up technology in the field of nano technology. Fabrication at nanometer scale is still at infant stage in India. Human eye can be realized as antenna system. In this article, we propose defective human eyes up to certain extent to be aided or replaced with optical antennas. This can be a game changer technology for biomedical applications in vision restoration. In this article, human eye retina (126 million photoreceptors) has been found to be replicated by quantum antennas. Quantum antenna has been designed and simulated using CST/HFSS software at 483 THz. The results has been found to be matching with human eye spectra. Eye retina each visual pigment molecule can emit and receive photon as per principle of light reciprocity. SPR(single photon response) based Quantum antenna is proposed to function as eye retina cylindrical rod, which can receive and transmit light signals at vision wavelength. The dimension of each rod falls between 1-3 micron as diameter and 6-50 micron length. The index of refraction of tissue is 1.336 at visible light. The retina is mimicked with quantum dielectric resonator antenna at 483THz. When optical signal strikes to rod or cone of retina, it gets converted into electrical signal, which passes to brain via optic nerves.

Exome sequencing analysis identifies novel homozygous mutation in ABCA4 in a Chinese family with Stargardt disease.

To identify the disease-associated mutations in a Chinese Stargardt disease (STGD) family, extend the existing spectrum of disease-causing mutations and further define the genotype-phenotype correlations. A Chinese STGD family and 200 normal controls were collected. Whole exome sequencing (WES) and bioinformatics analysis were performed to find the pathogenic gene mutation. Physico-chemical parameters of mutant and wildtype proteins were computed by ProtParam tool. Domains analysis was performed by SMART online software. HOPE online software was used to analyze the structural effects of mutation. Immunofluorescence, quantitative real-time polymerase chain reaction and Western blotting were used for expression analysis. Using WES, a novel homozygous mutation (NM_000350: c.G3190C, p.G1064R) in ABCA4 gene was identified. This mutation showed co-segregation with phenotype in this family. It was not found in the 200 unrelated health controls and absent from any databases. It was considered "Deleterious" as predicted by five function prediction softwares, and was highly conserved during evolution. ABCA4 was expressed highly in the human eye and mouse retina. The p.G1064R was located in AAA domain, may force the local backbone into an incorrect conformation, disturb the local structure, and reduce the activity of ATPase resulting in the disease pathology. We define a novel pathogenic mutation (c.G3190C of ABCA4) of STGD. This extends the existing spectrum of disease-causing mutations and further defines the genotype-phenotype correlations.

Disease Prediction Based On Retinal Images using Neural Network Classification

the eyes used to determine the health of someone. There are several maladies in human, like vascular diseases that leave telltale markings within the retina of human eyes. The image of the retina will be captured comparatively with a camera now each day with digital imaging technology there's abundantly advanced within the technology of computer analysis of the retinal pictures were accustomed identify the consequences of diseases like cardiovascular diseases in the human body. A retinal image provides the data of what's going to happen within the body of a human. Significantly, the retinal vessel shows the condition of the cardiovascular in the physical body. Retinal pictures will offer the data concerning pathological changes within the physical body caused due to the disease in the retina that reveals cardiovascular disease, disorder, diabetes, and stroke. Computer-aided analyzed the image of the retina for the diagnostic purpose of the malady. However, automation of retinal segmentation that is difficult as a result of that the retinal pictures are noisy, distinction low, and therefore the vessel breadth often varies from very large to very tiny. Therefore, during this project, we are able to implement automatic vessel segmentation approach supported the neural network strategies to offer info regarding blood vessel and vein within the human membrane. Finally, cardiovascular diseases and therefore the alternative diseases expected victimization the distinctive technique of comparison of CENTRAL RETINAL EQUIVALENT OF VEIN and CENTRAL RETINAL EQUIVALENT OF ARTERY measurements.

Principles of Organization of the Human Eye Retina and Their Use in Computer Vision Systems

This paper provides a summary of principles of organization of the human eye retina. The following principles are considered: locality during interacting neurons, ring organization of receptive fields with on- and off-centers (center-surround organization), specialization of neuron layers, organization of feedbacks, adaptation to lighting and contrast levels, and data volume reduction in a video stream. It is shown that the perfect organization of the human retina being used as a prototype allows to significantly improve technical characteristics of computer vision systems. The results of this research were used in creating a family of intelligent video cameras and a number of systems based on them and also in constructing specialized neural networks for primary information processing directly on a sensor matrix.