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. The primary lightsensing cells in the retina are the photoreceptor cells, which are of two types. Anatomy and physiology of the retina retinal microstructure the figure to the left below is a light micrograph illlustrating across section of the retina. Simple anatomy of the retina by helga kolb webvision. 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 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.
A comparative qualitative study of layers of retina in nocturnal and diurnal birds b narasinga rao, m pramila padmini, international online october december 2011 rjpbcs volume 2 issue 4. Simple anatomy of the retina webvision ncbi bookshelf. The retina is structured of several layers of nerve cells, photoreceptors, pigmentation and blood vessels which line the inside of the eyeball. As we prepare for agerelated macular degeneration awareness month in february, a closer look at the layers of the retina and their function. A deep learning model of the retina stanford university. Figure 2 eye, retina degeneration in a male f344n rat from a chronic study. 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. Retinal repair by transplantation of photoreceptor precursors pdf. The neuroretina consists of outer and inner segments of photoreceptors rods and cones, external limiting membrane, outer. Since manual segmentation of these layers is time consuming and prone.
Two decades since its introduction, oct has become indispensable for research, screening, diagnosing, and monitoring diseases of the macula and optic nerve head. This complex system of nerves sends impulses through the optic nerve back to the brain, which translates these messages into images that we see. The neuroretina consists of outer and inner segments of photoreceptors rods and cones, external limiting membrane, outer nuclear layer, outer plexiform layer, inner nuclear layer, inner plexiform layer, ganglion cell layer, nerve fiber layer and internal limiting membrane. Normal retina contains neuroretina and retinal pigment epithelium. Articles appearing here may contain statements, opinions, and information that have errors in facts, figures, or interpretation. Each layer of cells in this tissue serves a specific purpose. Fit all layers, whether or not selected, to the viewable page area. An initial estimate of 55 cell types in the retina masland, 2001 appears to have been something of an underestimate. The retina processes the information gathered by the photoreceptor cells and sends this information to the brain via the optic nerve. The retina is the innermost of the three tunics of the eye, surrounding the vitreous body and continuous posteriorly with the optic nerve. The retina is a thin layer of tissue that lines the back of the eye on the inside. The retina processes light through a layer of photoreceptor cells. All projects are first created or imported into the software and then operators have a variety of. Anatomy and physiology of the retina libreria universo.
Retinal anatomy and physiology ocular anatomy the eye is a fluid filled sphere enclosed by three layers of tissue. Guiding light the scientist magazine split spectrum. The thickness of this layer variesconsiderably across species, where. The inner retina consists of the internal limiting membrane through to the.
The outermost layer of the retina, the retinal pigment epithelium, is tightly attached to the choroid. To the right are drawn in complete outline a few of thecells whose cell bodies only are visible in the micrograph. 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. Layers of the retina eye health, the retina, eye anatomy. 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 retina serves a function analogous to that of the film or image sensor in a camera. 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.
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. Retinal layer segmentation of macular oct images using. It is composed of nerve tissue which senses the light entering the eye. Registered users can save articles, searches, and manage email alerts. Cell bodies and synapses all vertebrate retinas are composed of three layers of cell bodies and two layers of synapses cell bodies of rodscones. 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. This takes place in the retina, which is located in the back of the eye. The purpose of the retina is to receive light that the lens has focused. The iris contains two sets of muscles controlling the size of the pupil. Know your retinal layers heidelberg engineering gmbh. Jan 26, 2016 the retina at the back of the eye is essential for all vision. The retina is the sensory membrane that lines the inner surface of the back of the eyeball. Defect in the chm gene can cause choroideremia, leaky blood vessels can expand in the retina causing wet agerelated macular degeneration amd and diabetic retinopathy. The middle layer includes the iris, the ciliary body, and the choroid.
The retina is the innermost, lightsensitive layer of tissue of the eye of most vertebrates and. The retinal neuromethe census of its component cells continues to be re. The inner plexiform layer contains synapses of the photoreceptors and bipolar cells. 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. A comparative qualitative study of layers of retina in nocturnal and diurnal birds b narasinga rao, m pramila padmini, international online october. Oct interpretation in retinal disease executive clinical director retina and macula specialists jay m. Clinical sciences inner retinal layer thinning in parkinson. The internal layer, or the sensory part of the eye, the retina. Layers of retina definition of layers of retina by medical. The sur face layer of the retina contains about 20 types of ganglioncells. Lhacha wangdi resident ophthalmology, jdwnrh retina and layers 2. When a rainbow of white light enters the retina, funnelshape muller cells guide the beam through layers of cells and cellular processes to the photoreceptors rods and cones.
Haynie, od, faao financial disclosure i have received honoraria or am on the advisory board for the following companies. 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. Layers of retina article about layers of retina by the free. The inner layer of nerve tissue consists of three separate layers of neurons.
Individual cell imaging in the retina is very challenging due to many constraints such as ocular aberration reducing lateral resolution, eye motion artifacts and, a lack of good contrast of transparent cells. The neural retina consists of several layers of neurons interconnected by synapses, and is supported by an outer layer of pigmented epithelial cells. The retina is a complex transparent tissue consisting of several layers, only one of which contains lightsensitive photoreceptor cells. Learn vocabulary, terms, and more with flashcards, games, and other study tools. 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. The retina can be intimidating as its not easy to visualize the posterior pole and there is a bunch of pathology back there. Its pedagogical value and utility as a reference book is enhanced with didactic clinical images and illustrations, key.
The retina is composed of many vascular and cellular layers, forming an intricate and complex tissue. Macular retinal layer thicknesses provide useful diagnostic information and have been shown to correlate well with measures of disease severity in several diseases. Items refer to the human eye unless otherwise specified. 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 sensitivity to different kinds of light. Title transscleral optical phase imaging of the human. 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. Rods function mainly in dim light and provide blackandwhite vision. The primary layers of the retina from outermost surface to innermost surface. In general, the most numerous types of cones are the long and mid wavelength cones. Carl zeiss meditec advanced ocular care arctic dx macula risk genentech lampa advisory oct cross section of retinal. This section leans heavily on wyszecki and stiles 1982 an excellent book. In the second of three cell layers, called the inner nuclear lay er, lie one to four types of horizontal. Its composed of several layers, including one that contains specialized cells called photoreceptors. Layers of retina article about layers of retina by the.
A radial section of a portion of the retina reveals that the ganglion cells the output neurons of the retina lie innermost in. The outer layer is composed of the sclera and the cornea. In most primates the retina is about 200250 micrometers thick. Layers of retina definition of layers of retina by. Vision in humans the human eye functions somewhat like a camera. Importance correct attribution of vascular features in optical coherence tomography oct angiography depends on accurate segmentation of retinal layers objective to evaluate the segmentation of retinal layers among 3 oct angiography instruments in the central macula, an area where the superficial and deep vascular plexuses terminate.
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. Retina composed of inner neural or sensory layers and outer pigment epithelium. How it works retinal layers structure types of damage photoreceptors connective hole wrinkle in the macula sugar balance vitamin a. Layers of the retina choroid this is made up of a layer of blood vessels that supply oxygen and nutrients to the retina. The innermost eyeball layer is the retina that woks as computer that receives inputs from 100 million photodetectors, that are sampling the pattern of light and dark in the image formed by the. The retina at the back of the eye is essential for all vision. 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. The retina is composed of lightsensitive neurons arranged in three layers. Layers of the retina, martin missfeldt 1993 eye anatomy body anatomy medical illustrations eye facts the retina human eye medical school neuroscience physiology. The neuroretina consists of outer and inner segments of photoreceptors rods and cones, external limiting membrane, outer nuclear layer, outer plexiform layer. Assessment of segmentation of retinal layers by optical. 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. Mammalian retina consists of six major types of neurons including photoreceptors.
252 297 693 245 111 778 1043 117 88 1547 323 1266 241 43 119 272 1410 999 423 1426 226 796 1467 1054 1123 1515 140 1643 969 1389 860 233 9 1301 1150 736 1169 1459 955 1002 956 934 127 1174 915 134 174 100 1090 1348