Optics of the eye and its impact in vision: a tutorial
... formation. The eye moves due to the action of six external muscles, permitting fixation and scanning of the visual environment. The light reaching the eye is first refracted by the cornea, a thin transparent layer free of blood vessels of about 12 mm in diameter and around 0.55 mm thickness in the c ...
... formation. The eye moves due to the action of six external muscles, permitting fixation and scanning of the visual environment. The light reaching the eye is first refracted by the cornea, a thin transparent layer free of blood vessels of about 12 mm in diameter and around 0.55 mm thickness in the c ...
Response Characteristics of Single Cells in the Monkey Superior
... preference; 3, weak contralateral preference; 4, equal responses from both eyes; 5, weak ipsilateral preference; ...
... preference; 3, weak contralateral preference; 4, equal responses from both eyes; 5, weak ipsilateral preference; ...
GD-DTPA enhanced MRI of ocular transport in a rat model of
... using the arterial spin labeling (ASL) technique showed high basal blood flows in the ciliary body and retina of rat eyes (Li et al., 2008b). It was also shown that MRI can detect multiple anatomical retinal layers, and that the retinal and choroidal vascular layers bounding the retina can be detecte ...
... using the arterial spin labeling (ASL) technique showed high basal blood flows in the ciliary body and retina of rat eyes (Li et al., 2008b). It was also shown that MRI can detect multiple anatomical retinal layers, and that the retinal and choroidal vascular layers bounding the retina can be detecte ...
What is Glaucoma? - Paden Eye Care Center
... How is Glaucoma Diagnosed? The visual field test (a careful map of the side vision) has long been the “gold standard” for following the progress of advanced glaucoma. The problem with using visual fields for early diagnosis is that, the visual field is typically normal in early glaucoma, while the p ...
... How is Glaucoma Diagnosed? The visual field test (a careful map of the side vision) has long been the “gold standard” for following the progress of advanced glaucoma. The problem with using visual fields for early diagnosis is that, the visual field is typically normal in early glaucoma, while the p ...
Uveitis in dogs - Parry Medical Writing
... segment of the tract, and can be anterior (involving the iris), intermediate (involving the ciliary body) and posterior (involving the choroid). Panuveitis refers to inflammation in all parts of the tract. Since the different regions of the uveal tract are continuous, inflammation commonly involves ...
... segment of the tract, and can be anterior (involving the iris), intermediate (involving the ciliary body) and posterior (involving the choroid). Panuveitis refers to inflammation in all parts of the tract. Since the different regions of the uveal tract are continuous, inflammation commonly involves ...
Vitalux - EPGonline.org
... the retina. The macula allows you to see fine details directly in front of you such as words in a book or images on television. So while the entire retina lets you see that there is a book in front of you, the macula lets you see what is written in the book. There are two types of AMD, Dry AMD and W ...
... the retina. The macula allows you to see fine details directly in front of you such as words in a book or images on television. So while the entire retina lets you see that there is a book in front of you, the macula lets you see what is written in the book. There are two types of AMD, Dry AMD and W ...
Systematic Approach to a Case of Disc Pallor
... is below but one has to understand that there are no watertight compartments and significant overlap of diagnosis exists between each age group. Glaucoma can present with disc pallor at any age and has been deliberately omitted from the list and further discussion. The table depicts the causes for d ...
... is below but one has to understand that there are no watertight compartments and significant overlap of diagnosis exists between each age group. Glaucoma can present with disc pallor at any age and has been deliberately omitted from the list and further discussion. The table depicts the causes for d ...
The extra-retinal motion aftereffect - School of Psychology
... All stimuli were created using small, dim dots on a black background displayed on a large screen via a VSG 2/3 graphics board (see Movie 1 for an example). Adaptation stimuli consisted of a vertically moving, striped stimulus depicting two strips of horizontal lines measuring 20º by 72º and separate ...
... All stimuli were created using small, dim dots on a black background displayed on a large screen via a VSG 2/3 graphics board (see Movie 1 for an example). Adaptation stimuli consisted of a vertically moving, striped stimulus depicting two strips of horizontal lines measuring 20º by 72º and separate ...
CURRICULUM VITAE - Boston Retinal Implant Project
... and treatment of optic neuritis and ischemic optic neuropathy, which are the two most common forms of non-glaucomatous optic neuropathy in adults. Some of my significant findings include: 1) recognition that all women and most men who experience optic neuritis eventually developed multiple sclerosis ...
... and treatment of optic neuritis and ischemic optic neuropathy, which are the two most common forms of non-glaucomatous optic neuropathy in adults. Some of my significant findings include: 1) recognition that all women and most men who experience optic neuritis eventually developed multiple sclerosis ...
Innervation of the superior tarsal (Müller`s)
... dents, 4 ' 2728 a different nomenclature is generally applied because the distribution of the branches of the trigeminal nerve differs from that in humans. In particular, rodents have a thick infraorbital nerve caused by innervation of the vibrissae and other structures.27 Moreover, in the rat,28 th ...
... dents, 4 ' 2728 a different nomenclature is generally applied because the distribution of the branches of the trigeminal nerve differs from that in humans. In particular, rodents have a thick infraorbital nerve caused by innervation of the vibrissae and other structures.27 Moreover, in the rat,28 th ...
Preferred retinal loci and macular scotoma characteristics
... mining where the eccentric PRL is located except by monitoring the location of visual-stimuli images on the retina. Fig. 1 shows how visual stimuli can be directly monitored with an SLO to determine scotoma and PRL characteristics. Generally, in the low-vision population with central scotomas, there ...
... mining where the eccentric PRL is located except by monitoring the location of visual-stimuli images on the retina. Fig. 1 shows how visual stimuli can be directly monitored with an SLO to determine scotoma and PRL characteristics. Generally, in the low-vision population with central scotomas, there ...
THE LACRIMATION REFLEX
... the lateral part of the superior orbital fissure. It enters the lateral part of the fissure superior to the muscles and- embedded- in the periosteum. It then runs along the lateral wall of the orbit, superior to the lateral rectus and lateral to the lacrimal artery-. Just before reaching the gland t ...
... the lateral part of the superior orbital fissure. It enters the lateral part of the fissure superior to the muscles and- embedded- in the periosteum. It then runs along the lateral wall of the orbit, superior to the lateral rectus and lateral to the lacrimal artery-. Just before reaching the gland t ...
Soaring aspirations to cure, to heal, to serve.
... more than three million people in the U.S. and more than 60 million worldwide. Most cases of glaucoma result from increased pressure in the eye. In general, there are few if any symptoms. Vision loss occurs slowly, usually over many years. As a result, nearly half of those affected by glaucoma are u ...
... more than three million people in the U.S. and more than 60 million worldwide. Most cases of glaucoma result from increased pressure in the eye. In general, there are few if any symptoms. Vision loss occurs slowly, usually over many years. As a result, nearly half of those affected by glaucoma are u ...
Printing - Philosophical Transactions of the Royal Society B
... Retinal dialyses describe a peripheral retinal disinsertion between the edge of the retina and the ora serrata from sudden expansion of the ocular equator from blunt injury. They are responsible for up to 84 per cent of trauma-related retinal detachments. The detachment may evolve slowly, often year ...
... Retinal dialyses describe a peripheral retinal disinsertion between the edge of the retina and the ora serrata from sudden expansion of the ocular equator from blunt injury. They are responsible for up to 84 per cent of trauma-related retinal detachments. The detachment may evolve slowly, often year ...
Hereditary eye disease in dogs - British Veterinary Association
... (primary open angle glaucoma). In addition, clinical examination of puppies when they are still part of a litter (litter screening) can be used to identify signs of congenital/early onset inherited eye disease in affected puppies. When new potentially inherited conditions are considered for listing ...
... (primary open angle glaucoma). In addition, clinical examination of puppies when they are still part of a litter (litter screening) can be used to identify signs of congenital/early onset inherited eye disease in affected puppies. When new potentially inherited conditions are considered for listing ...
Cortical Metabolic Activity Matches the Pattern of Visual
... represented, there were alternating pale and dark bands in layer 4C (Fig. 2). They appeared to be ocular dominance columns, but no second label was available to prove their identity. In the opercular region, where the central visual field is represented, this pattern was absent. Instead, there were ...
... represented, there were alternating pale and dark bands in layer 4C (Fig. 2). They appeared to be ocular dominance columns, but no second label was available to prove their identity. In the opercular region, where the central visual field is represented, this pattern was absent. Instead, there were ...
The Cornea And Corneal Disease
... properly, and the presence of even the tiniest blood vessels can interfere with this process. To see well, all layers of the cornea must be free of any cloudy or opaque areas. The corneal tissue is arranged in five basic layers, each having an important function. These five layers are: ...
... properly, and the presence of even the tiniest blood vessels can interfere with this process. To see well, all layers of the cornea must be free of any cloudy or opaque areas. The corneal tissue is arranged in five basic layers, each having an important function. These five layers are: ...
Introduction to retinal straylight
... This subject is the cause of a lot of misunderstanding. Because more glare is experienced at night, one might think that straylight is stronger at night. This may be believed to be caused by a larger pupil size. Indeed, the amount of straylight is higher because of the larger pupil, but also the non ...
... This subject is the cause of a lot of misunderstanding. Because more glare is experienced at night, one might think that straylight is stronger at night. This may be believed to be caused by a larger pupil size. Indeed, the amount of straylight is higher because of the larger pupil, but also the non ...
Reprint - Victor Chong
... the SFD eye, in addition, the outer edge of the sub-RPE deposit and the inner portion of the ciliary body deposit were positively stained for elastin. In the control and SFD eyes, an antibody to type VI collagen highlighted retinal and choroidal vessels. In the SFD eye, the outer edge of the sub-RPE ...
... the SFD eye, in addition, the outer edge of the sub-RPE deposit and the inner portion of the ciliary body deposit were positively stained for elastin. In the control and SFD eyes, an antibody to type VI collagen highlighted retinal and choroidal vessels. In the SFD eye, the outer edge of the sub-RPE ...
Brain damage-related Vision Loss - Functional Classification (Word)
... Ventral stream (what?) - Dorsal stream (where?), Deficits only in brain damage (CVI, TBI, CVA) Presenter’s Notes The previous slide depicted the many brain areas that are involved in different components of functional vision. Yet, the processing from all those areas is seamlessly integrated. We woul ...
... Ventral stream (what?) - Dorsal stream (where?), Deficits only in brain damage (CVI, TBI, CVA) Presenter’s Notes The previous slide depicted the many brain areas that are involved in different components of functional vision. Yet, the processing from all those areas is seamlessly integrated. We woul ...
The Effects of Antioxidant Vitamins on Cataract
... • Once a cataract begins to develop there is nothing that can be done to prevent its growth. ...
... • Once a cataract begins to develop there is nothing that can be done to prevent its growth. ...
Peripheral aberrations in the human eye for
... measured objectively using techniques that analyze the reflection from the retina, including the double-pass technique [13,16,17] or the Hartmann–Shack wavefront sensor [9,18,19]. These measurements are most often performed in quasimonochromatic light in the near-infrared since light of these wavele ...
... measured objectively using techniques that analyze the reflection from the retina, including the double-pass technique [13,16,17] or the Hartmann–Shack wavefront sensor [9,18,19]. These measurements are most often performed in quasimonochromatic light in the near-infrared since light of these wavele ...
Full PDF
... Africa blowing direct from the sahara.It is hot, very dry and dusty so hot and dry that sometimes splits the trunk of trees. When it penetrates areas like guniea cost, it provides a welcome relief from to the most heat, and is beneficial to health. Itt is relatively cool wind to the area, in fact, f ...
... Africa blowing direct from the sahara.It is hot, very dry and dusty so hot and dry that sometimes splits the trunk of trees. When it penetrates areas like guniea cost, it provides a welcome relief from to the most heat, and is beneficial to health. Itt is relatively cool wind to the area, in fact, f ...
Document
... of compound eyes (as in the horseshoe crab Limulus) rather than from an aquatic single-chambered eye. Insect dorsal ocelli are also of this type, but they are generally under-focused and are not the principal organs of vision. The fourth type of eye (D) uses a spherical mirror instead of a lens, and ...
... of compound eyes (as in the horseshoe crab Limulus) rather than from an aquatic single-chambered eye. Insect dorsal ocelli are also of this type, but they are generally under-focused and are not the principal organs of vision. The fourth type of eye (D) uses a spherical mirror instead of a lens, and ...
CORNEAL ULCERS What is a corneal ulcer? The cornea is the
... trauma, such as a dog rubbing its eye on carpet, or due to a laceration, such as a cat scratch. The second most common cause is chemical burn of the cornea. This may happen when irritating shampoo or dip gets in the eye. Less common causes of corneal ulcers include bacterial infections, viral infect ...
... trauma, such as a dog rubbing its eye on carpet, or due to a laceration, such as a cat scratch. The second most common cause is chemical burn of the cornea. This may happen when irritating shampoo or dip gets in the eye. Less common causes of corneal ulcers include bacterial infections, viral infect ...
Retina
The retina (/ˈrɛtɪnə/ RET-i-nə, pl. retinae, /ˈrɛtiniː/; from Latin rēte, meaning ""net"") is the third and inner coat of the eye which is a light-sensitive layer of tissue. The optics of the eye create an image of the visual world on the retina (through the cornea and lens), which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical events that ultimately trigger nerve impulses. These are sent to various visual centres of the brain through the fibres of the optic nerve.In vertebrate embryonic development, the retina and the optic nerve originate as outgrowths of the developing brain, so the retina is considered part of the central nervous system (CNS) and is actually brain tissue. It is the only part of the CNS that can be visualized non-invasively.The retina is a layered structure with several layers of neurons interconnected by synapses. The only neurons that are directly sensitive to light are the photoreceptor cells. These are mainly of two types: the rods and cones. Rods function mainly in dim light and provide black-and-white vision, while cones support daytime vision and the perception of colour. A third, much rarer type of photoreceptor, the intrinsically photosensitive ganglion cell, is important for reflexive responses to bright daylight.Neural signals from the rods and cones undergo processing by other neurons of the retina. The output takes the form of action potentials in retinal ganglion cells whose axons form the optic nerve. Several important features of visual perception can be traced to the retinal encoding and processing of light.