#optic cup

[bpod-bpod]

All Eyes

From antelopes to zebrafish, aardvarks to zebus and all the vertebrates in between – including us – you’ll find rounded eyeballs are a common feature. But how does this shape come about? The precursor to vertebrate eyes is the optic vesicle, a developing tissue with two layers: an outer layer of retinal pigmented epithelium (RPE) and an inner layer of neural retina. Neural retina is known to create mechanical forces that help curve the optic vesicle into an optic cup. Researchers now investigate whether RPE cells also contribute, using zebrafish whose RPE cells are genetically engineered to fluoresce. Live-cell fluorescence microscopy of zebrafish embryos (pictured) revealed RPE cells (green) flattening and stretching out to cover the whole neural retina. Preventing this flattening by adding a chemical that interfered with the cells’ architecture stopped the optic cup from becoming curved. RPE is, therefore, also essential in creating the rounded shape of our eyes.

Written by Lux Fatimathas

Video from work by Tania Moreno-Mármol and colleagues

Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Campus de la Universidad Autónoma de Madrid, Madrid, Spain

Video originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)

Published in eLife, September 2021

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[bpod-bpod]

Optical Design

A newly conceived human embryo’s eyes start to develop around five weeks. Layers of cells fold inwards to create structures called the optic cups. These cells then start to mature and specialise as shown in the image: the green circular object is the developing lens; the white tulip-like region the developing retina; and the surrounding red layer contains protective pigmented cells. Here, scientists have identified a pair of chemicals with opposing gradients of concentration along the optic cup. How concentrated the chemicals are in the cells determines what genes are switched on and this, in turn, defines what type of cell they become. This study shows that the chemical gradients come from genes which are known to be evolutionary similar in humans, flies and even worms – further proof our eyes are not the product of intelligent design.

Written by Julie Webb

Image from work by Revathi Balasubramanian and Xuanyu Min, and colleagues

Department of Ophthalmology, Columbia University, New York, NY, USA

Image originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)

Published in Science Advances, November 2021

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[jackoshadows]

Human brain organoids assemble functionally integrated bilateral optic vesicles

Human induced pluripotent stem cells (iPSCs) can be used to generate brain organoids containing an eye structure called the optic cup, according to a study published August 17 in the journal Cell Stem Cell. The organoids spontaneously developed bilaterally symmetric optic cups from the front of the brain-like region, demonstrating the intrinsic self-patterning ability of iPSCs in a highly complex biological process.

Many aspects of human brain development and diseases can be studied using 3D brain organoids derived from pluripotent stem cells, which can give rise to all cell types in the body. Researchers previously used human embryonic stem cells to generate the optic cup, which gives rise to the retina—the light-sensitive layer of tissue at the back of the eye. Another study demonstrated that optic-cup-like structures can be generated from iPSCs, which are derived from adult cells that have been genetically reprogrammed back into an embryonic-like pluripotent state.

Our work highlights the remarkable ability of brain organoids to generate primitive sensory structures that are light sensitive and harbor cell types similar to those found in the body,” says senior study author Jay Gopalakrishnan of University Hospital Düsseldorf. “These organoids can help to study brain-eye interactions during embryo development, model congenital retinal disorders, and generate patient-specific retinal cell types for personalized drug testing and transplantation therapies.”

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[ijtsrd]

Survey on Various Methods of Detecting Glaucoma

By Swathi Anil | Prof. Elizabeth Issac"Survey on Various Methods of Detecting Glaucoma"

Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-2 , February 2018,

URL: http://www.ijtsrd.com/papers/ijtsrd10704.pdf

Direct URL: http://www.ijtsrd.com/computer-science/bioinformatics/10704/survey-on-various-methods-of-detecting-glaucoma/swathi-anil

call for paper social science , open access journal of chemistry, management journal

Glaucoma is an irreversible chronic eye disease it leads to vision loss. It is an eye disease which occurs due to the increased/decreased fluid pressure inside the eye. The pressure inside the normal eye is usually below 21mm of Hg. But when the pressure inside the eye(s) increases more than 21mm of Hg, the optic nerve gets damaged. This can permanently damage vision in the effected eye(s) and can lead to blindness if left untreated. The available scanning methods of glaucoma are Heidelberg Retinal Tomography (HRT), Scanning Laser Polarimetry (SLP) and Optical Coherence Tomography (OCT). The existing methods are expensive and require experienced clinicians to use them. So, there is a need to diagnose glaucoma accurately with low cost. As the symptoms only occur when the disease is quite advanced so that glaucoma is called the silent thief of sight. Glaucoma cannot be cured, but its development can be slowed down by treatment. Therefore, detecting glaucoma in time is critical. Manual analysis of the eye is time consuming and the accuracy of the parameter measurements also varies with different clinicians. To overcome these problems with manual analysis, the objective of this survey is to introduce a method to automatically analyze the fundus images of the eye. Automatic analysis of this disease is much more effective than manual analysis.

[ijtsrd]

Analysis on Glaucoma Detection

BY Sherin. J | Devi Kala Rathinam. D | Santhiya Grace. A" Analysis on Glaucoma Detection" 

Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-5 , August 2018, 

URL: http://www.ijtsrd.com/papers/ijtsrd15756.pdf 

Direct URL: http://www.ijtsrd.com/computer-science/bioinformatics/15756/analysis-on-glaucoma-detection/sherin-j

ugc listed journals, indexed journal, special issue publication

Glaucoma is a disease which leads to a permanent blindness to a person. Many techniques are available in medical industry to detect glaucoma. Some traditional techniques are HRT and COT. But both of them are cost effective and time consuming. These inefficiencies leads to the emergence of automatic computer aided system which can detect glaucoma in less time. Optic disc and optic cup smashes an important role in glaucoma detection. This paper gives an study of various techniques that are used in glaucoma detection using automated systems 

[ijtsrd]

Analysis on Glaucoma Detection

By Sherin. J | Devi Kala Rathinam. D | Santhiya Grace. A"Analysis on Glaucoma Detection" 

Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-5 , August 2018, 

URL: http://www.ijtsrd.com/papers/ijtsrd15756.pdf 

http://www.ijtsrd.com/computer-science/bioinformatics/15756/analysis-on-glaucoma-detection/sherin-j

open access journal of management, call for paper chemistry, ugc approved journals for management

Glaucoma is a disease which leads to a permanent blindness to a person. Many techniques are available in medical industry to detect glaucoma. Some traditional techniques are HRT and COT. But both of them are cost effective and time consuming. These inefficiencies leads to the emergence of automatic computer aided system which can detect glaucoma in less time. Optic disc and optic cup smashes an important role in glaucoma detection. This paper gives an study of various techniques that are used in glaucoma detection using automated systems 

[houseofmind]

The progression from A-D depicts the development of the human eye. The neural portion of the eye, called the retina, is part of the central nervous system (CNS).

A. In early development, the retina forms as an outpocket from the neural tube and is called the optic vesicle.

B. This optic vesicle invaginates to make the optic cup. 

C./D. The optic cup's inner wall becomes the retina, while the pigment epithelium originates from the outer wall. 

The retina contains photoreceptors (cones and rods) whose electrical activity is converted into action potentials and sent to the brain via the optic nerve. The retina also has a complex multi-layered structure populated by different kinds of neurons.