The retina is a layer of tissue in the back of your eye that senses light and sends images to your brain. These cells are connect to the photoreceptors that. The figure to the left below is a light micrograph illlustrating across section of the retina. Lhacha wangdi resident ophthalmology, jdwnrh retina and layers 2. Retinal detachment is an eye problem that happens when your retina a lightsensitive layer of tissue in the back of your eye is pulled away from its normal position. The retina is structured of several layers of nerve cells, photoreceptors, pigmentation and blood vessels which line the inside of the eyeball. Retina, layer of nervous tissue that covers the inside of the back twothirds of the eyeball, in which stimulation by light occurs, initiating the sensation of vision.
Anatomy and physiology of the retina retinal microstructure the figure to the left below is a light micrograph illlustrating across section of the retina. Registered users can save articles, searches, and manage email alerts. Despite its peripheral location, the retina or neural portion of the eye, is actually part of the central nervous system. Retina is a neurosensory tissue lining the back of the eye and is responsible for light detection and relaying the signal to the visual cortex in the brain. Simple anatomy of the retina webvision ncbi bookshelf. Learn vocabulary, terms, and more with flashcards, games, and other study tools. In new generation it is only opthalmologst examine patients retina in inner limiting membr new nerve fiber layer generation ganglion cell it inner plxiform layer is inner neuclr layer. Analysis of expression of transcription factors in early human retina here, we analyze the expression of transcription factors that are involved in the early development of the retina in human embryos at 612 weeks postconception. The inner retina consists of the internal limiting membrane through to the. Several parts of the eye are associated with the retina. The retina at the back of the eye is essential for all vision. Indeed, with conventional octa all retinal layers, including the avascular outer retina, appeared to contain flow signal, and no natural boundary could be defined. Cell bodies and synapses all vertebrate retinas are composed of three layers of cell bodies and two layers of synapses cell bodies of rodscones. Simple anatomy of the retina by helga kolb webvision.
Like the inner nuclear layer, the outer nuclear layer contains several strata of oval nuclear bodies. Cells in the retina are arrayed in discrete layers. In more detailed descriptions of the retina, the three primary retinal layers are further divided into seven layers gray, 1918. The retina is the lightsensitive tissue that lines the inside of the eye. The inner wall of the optic cup gives rise to the retina, while the outer wall gives.
How it works retinal layers structure types of damage photoreceptors connective hole wrinkle in the macula sugar balance vitamin a. Reattachment of retina and retinoschisis in pitmacular syndrome by surgicallyinduced vitreous detachment and gas tamponade. This remains a challenging task, as retinal layers can be heavily distorted in the presence of pathological biomarkers. This most important part of the eye has a basic structure similar to that of a threelayer cake, with the bodies of nerve cells arrayed in three rows separated by two layers packed with synaptic connections. In most primates the retina is about 200250 micrometers thick. The micrograph anddrawing illustrate that the retina is organized both vertically in columns andhorizontally in layers. Pdf disorganization of retinal inner layers dril and. A second major component of the retina is the retinal pigment epithelium rpe, a separate onecell thick epithelial layer that in the embryo arises separately from the neural retina see fig.
Oct layers of the retina medical educational videos, atlases, books, cases and drugs index for medical students and doctors and health education for public. The retina is composed of lightsensitive neurons arranged in three layers. The internal layer, or the sensory part of the eye, the retina. This is where the rods and cones are located that convert light into electrical. Reattachment of retina and retinoschisis in pitmacular. The decorrelation viewed as a maximal projection image imaged blood flow. There are many things i could cover in this chapter, but ive decided to keep things simple and only discuss a few topics like diabetic retinopathy and retinal detachments. The optic nerve contains the ganglion cell axons running to the brain and, additionally, incoming blood vessels that open into the retina to vascularize the retinal layers and neurons fig. The retina is the innermost of the three tunics of the eye, surrounding the vitreous body and continuous posteriorly with the optic nerve. Carl zeiss meditec advanced ocular care arctic dx macula risk genentech lampa advisory oct cross section of retinal. Anatomy and physiology of the retina libreria universo. In a high quality, high resolution oct scan, at least retinal layers can be identified, the names of which are now widely accepted clinically see image. Cellular remodeling in mammalian retina induced by retinal detachment by steve fisher, geoffrey p.
The retina is a thin layer of tissue that lines the back of the eye on the inside. Amacrine cells lie close to ganglion cells near the surface of the retina. The two layers that comprise the retina are an outer pigmented layer called the pigment epithelium, which adheres to the choroid, and an inner layer of nerve tissue called the sensory or neural retina. From the outside choroid to the inside vitreous chamber, can be distinguished the ten layers of the retina. The retina serves a function analogous to that of the film or image sensor in a camera. The retina is a complex transparent tissue consisting of several layers, only one of which contains lightsensitive photoreceptor cells. The retina is the sensory membrane that lines the inner surface of the back of the eyeball. Figure 2 eye, retina degeneration in a male f344n rat from a chronic study. The retina is normally red, reflecting blood flow, and is pale in anemia or ischemia. The inner retina consists of the internal limiting membrane through to the external limiting membrane, and the outer retina consists of the photoreceptor layers through to the choroid. Assessment of segmentation of retinal layers by optical. At the fovea, the layers of the retina are excavated as a result there is a modification of the layers the foveola is the most central part of the fovea and is comletely rod and blue cone free approximately 10,000 are found at the foveola the foveal pit acts as a mirror and one can see. The retina can be intimidating as its not easy to visualize the posterior pole and there is a bunch of pathology back there. Apr, 2018 the retina is the innermost of the three tunics of the eye, surrounding the vitreous body and continuous posteriorly with the optic nerve.
Rod photoreceptors detect motion, provide blackandwhite vision and. This section leans heavily on wyszecki and stiles 1982 an excellent book. The various layers appear as either bright hyperreflective or dark hyporeflective bands depending on whether the layer is reflecting or absorbing light. Blood supply to the retina choroid supplies 85% mainly outer retina photoreceptors central retinal artery supplies 15% inner retinal layer 23. The inner layer of nerve tissue consists of three separate layers.
Its composed of several layers, including one that contains specialized cells called photoreceptors. The retinal neuromethe census of its component cells continues to be re. The optics of the eye create a focused twodimensional image of the visual world on the retina, which translates that image into electrical neural impulses to the brain to create visual perception. Lewis, kenneth a linberg, edward barawid and mark v. Outer nuclear layer an overview sciencedirect topics. Thin delicate layer of nervous tissue surface area of 266 mm2 extends from optic disc to ora serrata 3. By the standards of other cns regions, retinal neurons are miniscule a the layers of the mouse retina.
As part of normal anatomy, layers of the inner retina become thinner and terminate as they approach the center of the fovea. In this context, the present paper focuses on providing more accurate retinal layer segmentations in pathological eyes, at clinicallyrelevant speeds. The retina is actually an extension of the brain, formed embryonically from neural tissue and connected to the brain proper by the optic nerve. Vision in humans the human eye functions somewhat like a camera.
Haynie, od, faao financial disclosure i have received honoraria or am on the advisory board for the following companies. During development, the retina forms as an outpocketing of the diencephalon, called the optic vesicle, which undergoes invagination to form the optic cup figure 11. The neuroretina consists of outer and inner segments of photoreceptors rods and cones, external limiting membrane, outer nuclear layer, outer plexiform layer. The layers of the retina, in the order light strikes them, are the optic nerve fiber layer, ganglion cell layer, inner synaptic layer, bipolar cell layer, outer synaptic layer, layer of rods and cones, and pigment epithelium. The photoreceptors are at the top of this rendering, close to the pigment epithelium. A radial section of a portion of the retina reveals that the ganglion cells the output neurons of the retina lie innermost in. The purpose of the retina is to receive light that the lens has focused. Because the retina is a laminar structure with a corresponding stratification of blood supply, segmentation of the retina in specific layers allows simple en face visualization of the corresponding vascular supply in that layer. The vitreous is a clear gellike substance that fills in the back cavity of the eye which is lined by the retina.
The bodies of horizontal cells and bipolar cells compose the inner nuclear layer. This is a lot of topics, so ive tried to keep things simple and to the point. Pdf normal retina contains neuroretina and retinal pigment epithelium. The retina is the innermost, lightsensitive layer of tissue of the eye of most vertebrates and some molluscs. The retina functions in a manner similar to film in a camera. The retina is the innermost layer of the eye the tunica intima or internal tunic and is comparable to the film inside of a camera. The retina is the innermost, lightsensitive layer of tissue of the eye of most vertebrates and. Retina is comprehensive threevolume part edition or an ebook that provides a unique compendium of current knowledge on the science, maladies, diagnostics, and the medical and surgical treatments of the retina. Retina composed of inner neural or sensory layers and outer pigment epithelium. Know your retinal layers heidelberg engineering gmbh.
This introduction to the retina covers all the basics. Layers of retina definition of layers of retina by medical. Two decades since its introduction, oct has become indispensable for research, screening, diagnosing, and monitoring diseases of the macula and optic nerve head. Tears can form in the retina, creating a risk of retinal detachment and severe loss of vision. Fit all layers, whether or not selected, to the viewable page area. For example, in one seven layer organization the following are distinguished. Retinal repair by transplantation of photoreceptor precursors pdf. The retina creates an image projected on its surface with help of the cornea and crystalline lens, and transforms it into nerve impulses sent to the brain. Fovea at the fovea, the layers of the retina are excavated as a result there is a modification of the layers the foveola is the most central part of the fovea and is comletely rod and blue cone free approximately 10,000 are found at the foveola. It is composed of nerve tissue which senses the light entering the eye. The retina is a lightsensitive layer of nerve tissue lining the inner surface of the eye. Choroid this is made up of a layer of blood vessels that supply oxygen and. The primary layers of the retina from outermost surface to innermost surface. The optical elements within the eye focus an image onto the retina of the eye, initiating a series of chemical and electrical events within the retina.
Mild retinal degeneration, featuring loss of rod and cone photoreceptor processes, singlecell necrosis of outer nuclear layer photoreceptor cells, hypocellularity and disorganization of the inner and outer nuclear layers, and narrowing or absence of the plexiform. It provides the sharp, central vision needed for reading, driving and seeing fine detail. It takes the visual information transmitted by beams of light reflecting off of objects and converts that information into a neural image that it. Oct interpretation in retinal disease executive clinical director retina and macula specialists jay m. Jan 26, 2016 the retina at the back of the eye is essential for all vision. Retinal degeneration, remodeling and plasticity by bryan william jones, robert e. Eye anatomy brain anatomy opthalmic technician optical coherence tomography optometry school eye facts ganglion the retina eyes. Retinal vascular layers in macular telangiectasia type 2. To elucidate the relationship between disorganization of retinal inner layers drils and retinal function in diabetic patients without diabetic retinopathy dr and with nonproliferative.
Normal retina contains neuroretina and retinal pigment epithelium. Each layer of cells in this tissue serves a specific purpose. Learn about the symptoms, diagnosis, and treatment of retinal detachment and find. This is a single layer of cells that provide essential nutrition. They can affect your vision, and some can be serious. To the right are drawn in complete outline a few of thecells whose cell bodies only are visible in the micrograph. Ganglion cell layer layers of the retina interpretation of oct images high resolution spectral oct nerve fiber layer. The retina is a thin, semitransparent, multilayered sheet of neural tissue that lines the inner aspect of the posterior twothirds of the wall of the globe. Light must pass through the overlying layers to reach the photoreceptor cells, which are of two types, rods and cones, that are differentiated structurally by their distinctive shapes and functionally by their. Mammalian retina consists of six major types of neurons including photoreceptors. An initial estimate of 55 cell types in the retina masland, 2001 appears to have been something of an underestimate. This most important part of the eye has a basic structure similar to that of a three layer cake, with the bodies of nerve cells arrayed in three rows separated by two layers packed with synaptic connections.
As we prepare for agerelated macular degeneration awareness month in february, a closer look at the layers of the retina and their function. Clinical sciences inner retinal layer thinning in parkinson. Layers of retina article about layers of retina by the free. The purpose of the retina is to receive light that the lens has focused, convert the light into neural signals, and send these signals on to the brain for visual recognition. The neural retina consists of several layers of neurons interconnected by synapses, and is supported by an outer layer of pigmented epithelial cells. This layer senses light and sends signals to the brain so you can see. The cuboidal cells of the rpe are heavily pigmented. Layers of retina definition of layers of retina by. Retinal tears the retina is the inner lining of the eye. This interactive image shows the layers of the retina in a section stained with hematoxylineosin. Pathological oct retinal layer segmentation using branch.
Items refer to the human eye unless otherwise specified. The retina is the layer of nerve cells lining the back wall inside the eye. A radial section of a portion of the retina reveals that the ganglion cells. Between the outer and inner nuclear layers is the outer plexiform layer, which contains the axon terminals of photoreceptors, the dendrites of bipolar and cell. Macula rich in cones, has more ganglion cells per area than elsewhere.
Our work demonstrates that early developing neural retinas can be divided into two layers, the outer and inner neuroblast layers. Cell bodies and synapses all vertebrate retinas are composed of three layers of cell bodies and two layers of synapses cell bodies of rodscones cell bodies of bipolar cells cell bodies of ganglion cells 11. This complex system of nerves sends impulses through the optic nerve back to the brain, which translates these messages into images that we see. There are two types of photoreceptor cells in the human eye rods and cones. B the bipolar cell shown in a is reproduced at its correct scale on an image showing a.
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