Despite its peripheral location, the retina or neural portion of the eye, is actually part of the central nervous system . During development, the retina forms as an outpocketing of the diencephalon, called the optic vesicle, which undergoes invagination to form the optic cup (Figure 11.3; see also Chapter 22).
What is the retina made of?
The retina is the sensory membrane that lines the inner surface of the back of the eyeball. It’s composed of several layers, including one that contains specialized cells called photoreceptors . There are two types of photoreceptor cells in the human eye — rods and cones.
What is the retina?
The retina contains millions of light-sensitive cells (rods and cones) and other nerve cells that receive and organize visual information. Your retina sends this information to your brain through your optic nerve, enabling you to see.
Is retina a nerve cell?
The retina of your eye consists of many interconnected layers of nerve cells, some of which are sensitive to light. Most people have heard of the two types of photoreceptors used to form images: the rod and cone cells.
Is the retina part of the optic nerve?
The optic nerve connects the retina to the visual cortex in the back of the brain . Increased intracranial pressure, tumours, and increased vascular pressure in the eye are possible mechanisms by which the optic nerve can become damaged, impairing vision.
What are signs of optic nerve damage?
- Pain. Most people who develop optic neuritis have eye pain that’s worsened by eye movement. ...
- Vision loss in one eye. Most people have at least some temporary reduction in vision, but the extent of loss varies. ...
- Visual field loss. ...
- Loss of color vision. ...
- Flashing lights.
What diseases cause optic nerve damage?
Some of the more common eye diseases that cause optic nerve damage include glaucoma, optic neuritis, optic nerve atrophy and optic nerve head drusen .
What is the purpose of the retina in the eye?
The retina is an essential part of the eye that enables vision. It’s a thin layer of tissue that covers approximately 65 percent of the back of the eye, near the optic nerve. Its job is to receive light from the lens, convert it to neural signals and transmit them to the brain for visual recognition .
What is retina in simple words?
Retina: The retina is the nerve layer that lines the back of the eye , senses light, and creates impulses that travel through the optic nerve to the brain. There is a small area, called the macula, in the retina that contains special light-sensitive cells. The macula allows us to see fine details clearly.
What would happen if the retina got folded and wrinkled?
When the scar tissue contracts , it causes the retina to wrinkle, or pucker, usually without any effect on central vision. However, if the scar tissue has formed over the macula, our sharp, central vision becomes blurred and distorted.
What are the signs of retina problems?
- Dim central vision.
- Distorted central vision.
- Straight lines that appear wavy.
- Spots in the central vision that may appear blurry or dark.
- Images that appear then disappear.
- Double Vision.
- Floaters.
- Flashing Lights.
Can stress cause retinal detachment?
The simple answer is no, stress cannot cause retinal detachment . Retinal detachment is due to tears in the peripheral retina. Retinal detachment occurs in less than 1 in 10,000 people and can occur at any age but is more likely to affect people over age 40.
Is retinal damage reversible?
In many cases, damage that has already occurred can’t be reversed , making early detection important. Your doctor will work with you to determine the best treatment. Treatment of retinal disease may be complex and sometimes urgent.
Can a retina regenerate?
Unlike in fish and frogs, the human retina doesn’t regenerate , and the vision loss caused by damage to cells in the back of the eye – be it genetic or physical – can rarely be fixed.
What are the nerve cells in the retina?
There are five types of neurons in the retina: photoreceptors, bipolar cells, ganglion cells, horizontal cells, and amacrine cells .
What part of the retina is responsible for the sharpest vision?
Near the centre of the retina is the macula. The macula is a small highly sensitive part of the retina. It is responsible for detailed central vision, the part you use when you look directly at something. It contains the fovea , the area of your eye which produces the sharpest images of all.
