Retina

The retina is a very sensitive inner coat of the eye. It consists of ten layers, which are inner limiting membrane, nerve fiber layer, Ganglion cells layer, inner plexiform layer, inner nuclear layer, outer plexiform layer, outer nuclear layer, external limiting membrane, photoreceptors (rods and cones) and retinal pigment epithelium. Also, it has a yellow spot, called macula, which is the important area for high acuity vision. In the retina, the light rays are converted into electrical signals then sent to the brain through the optic nerve. Any imperfection in these layers can cause vision loss. This vital tissue is susceptible to many different systemic diseases such as anemia, hypertension and diabetes mellitus. The retina of diabetics is very distinct from the retina of non-diabetic people. Diabetes Mellitus (DM) is a chronic disease which occurs when the sugar concentration in blood increases as a result of beta cells defection. Beta cells are located in the pancreas and they control the percentage of sugar in blood by producing insulin, which is a hormone that is responsible for breaking down the sugar and converting it to energy. With diabetes mellitus, either the patient’s body can not…

separated from the rest of the eye. This cause vision changes and blindness if not taken care of properly. Proper nursing care and patient compliance is essential in restoring functioning of the eye and protecting against serious complications. ( Williams, 2011)(WebMD, 2016). Anatomy and Physiology The retina in a thin layer of tissue that is covered in nerve cells at the back of the eye. The retina is the tissue that houses the rods and cones that give us vision. It has two areas on it that…

Change in Visual Acuity with Eccentricity Humans have a large vison field so it is important to not only test the central vison but also at the peripherals of the retina. This is because individuals tend to not notice vison loss at the peripherals compared to central vision as when an individual views an object they move their eyes and fixate on that object by using their central vison and not their peripheral. Visual acuity is highest at the fovea and lowest at the peripheral which ensures high…

The other day, I was thinking about how amazing it is to be able to perceive the world around me. I understood that from the retina to the brain, perception goes from complex to extremely complex. In other words, being able to experience the real world is one of the marvelous opportunities that we have. This phenomenon starts with light getting in contact with the cornea continuing to the back of the eyes, to the retina, before light goes to the optic nerve and end up in the brain. This process…

The first area the light hits is the 1.cornea and that is where the first bend occurs. It then goes to the 2.aqueous humor and through the 3.pupil where it then gets refracted once again by the 4.lens and the light is centered to the 6.retina, but not before it goes through the 5.vitreous humor. The lens is naturally convex lens, so the light bends towards the center. The path of the light for people with Glaucoma remains the same except the light reaches the retina through a much narrower…

called the Retina is apart of the Central Nervous System. The Retina is how people are nearsighted they can see they can see near objects, but they can’t focus enough to see far. Farsightedness or being farsighted is when you see far, but you can’t see near objects clearly. The 130 receptor cells are also known as rods and cones. The Central Nervous System is apart of the Nervous System, but the Central Nervous System makes up the brain, spinal cord, and retina. The Nervous System is a…

core organ (the brain) to understand external stimuli. The eye is extremely complex and requires various components for it to complete its function. The eye has 3 main layers the sclera, which maintains and supports the shape of the eye; the choroid, which provides oxygen and nourishment to the eye and includes the pupil, iris, lens; and the retina, which allows us to piece images together and includes two types of photoreceptors, cones and rods which helps the human eye see across multiple…

revolutionary piece of technology that can make people who have lost their eyesight see again. First, “a tiny retinal implant is put into the human eye, and then later, a gadget is put onto the human body. With the small retinal implant, it receives radio messages and transfers these messages to the brain through the optic nerve. The device acts as a stimulator, in which it is set up at any position in the visual pathway to electrically stimulate neurons and retinal cells” (Ranjakumar,…

Macular degeneration is the leading cause of blindness in America. It affects people between sixty five and older, which is a large proportion of Americans today. The macula, an oval shaped pigment near the near the center of the retina, is responsible for the sharp, high-acuity, central vision. Within the macula are the fovea and foveole, high density cones. The AMD affects the macula which causes for central vision to occur. Already 1.75 million Americans have AMD and is expected to increase…

Light is what helps us see every day, and without it we know that it would be much harder to observe our surroundings. Light helps us see the detail in objects and the beauty in our environment. Thanks to a few functions of our eye we can gather that light to form an image on our retina. For many people, eye sight tends to get worse as they age and corrective lenses are needed. Contact lenses provide a comfortable way to allow someone to see things with a 20/20 vision. To understand how the…