There is an estimated 120 million rod photoreceptor cells in the retina. While they don't provide high-resolution or color vision, rod cells provide peripheral vision, perceive movement and shades of gray, and can function in low-light conditions. Most rod photoreceptor cells are located outside the macula. The highest concentration is in the fovea (or fovea centralis), which is a central pit within the macula that contains only cone cells. It’s estimated that there are 6 million to 7 million cone cells in the retina, with most of them located in the macula. There is a very high concentration of cone photoreceptor cells in the macula, which are responsible for our color vision and our ability to see fine details. These cells - called cones and rods - make our sense of vision possible by converting light rays into signals that are transmitted to the brain. There are two types of photoreceptor cells in the retina. Macular pigment protects cells in the macula from the potentially harmful effects of high-energy visible (HEV) blue light from the sun and other sources, including the LED screens of computers and phones. The yellow color is due to the macular pigment, which is composed mainly of lutein and zeaxanthin from your diet. Like many medical terms, macula lutea is Latin: Macula means “spot” and lutea means “yellow.” The macula lutea is a very small spot in the central retina - it’s just 5.5 millimeters (less than a quarter-inch) in diameter.Īlso, when viewed or photographed by your eye doctor, the macula lutea has a yellowish appearance (in contrast to the rest of the retina, which is red). The macula makes it possible to see in great detail while the rest of the retina provides peripheral (side) vision. The macula allows one to appreciate detail and perform tasks that require central vision, such as reading.” “It is the small and highly sensitive part of the retina that’s responsible for detailed central vision. “The macula is the area of the retina that allows us to see 20/20,” says Maria Richman, OD, spokeswoman for the American Optometric Association. The macula is responsible for visual acuity, central vision and color vision. 28, 2020.The macula lutea - more commonly called the macula - is the most sensitive spot in the center of the light-sensitive retina in the back of the eye. Age-related macular degeneration preferred practice pattern - 2019. Have AMD? Save your sight with an Amsler grid.Evaluation of the ophthalmologic patient.Complex retinal detachment: Proliferative vitreoretinopathy and giant retinal tears.It slowly affects the retina and causes loss of night and side vision. Retinitis pigmentosa is an inherited degenerative disease. Many people will first have the dry form, which can progress to the wet form in one or both eyes. There are two types - wet macular degeneration and dry macular degeneration. This causes symptoms such as blurred central vision or a blind spot in the center of the visual field. In macular degeneration, the center of your retina begins to deteriorate. The hole may develop from abnormal traction between the retina and the vitreous, or it may follow an injury to the eye. A macular hole is a small defect in the center of the retina at the back of your eye (macula). This membrane pulls up on the retina, which distorts your vision. Epiretinal membrane is a delicate tissue-like scar or membrane that looks like crinkled cellophane lying on top of the retina. Or you may develop new, abnormal capillaries that break and bleed. This causes the retina to swell, which may blur or distort your vision. If you have diabetes, the tiny blood vessels (capillaries) in the back of your eye can deteriorate and leak fluid into and under the retina. This usually occurs when fluid passes through a retinal tear, causing the retina to lift away from the underlying tissue layers. A retinal detachment is defined by the presence of fluid under the retina. It's often accompanied by the sudden onset of symptoms such as floaters and flashing lights. A retinal tear occurs when the clear, gel-like substance in the center of your eye (vitreous) shrinks and tugs on the thin layer of tissue lining the back of your eye (retina) with enough traction to cause a break in the tissue. TypesĬommon retinal diseases and conditions include: Untreated, some retinal diseases can cause severe vision loss or blindness. Depending on your condition, treatment goals may be to stop or slow the disease and preserve, improve or restore your vision. Treatment is available for some retinal diseases.
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