Eyes and Eye Health
Sight is an important sense for perceiving the world around us. Our eyes have a lot to do, and must constantly compensate for external stimuli.
Sight is the most important sense we have for perceiving the things around us. With their highly complex structure and fine motor skills, our eyes are a true work of wonder. Our eyes have a lot to do, and must constantly compensate for external stimuli. What if your eyes are reddened and irritated or feel dry? What are common eye problems and how can they be treated?
Elements of the eye
The wall of the eyeball has three layers: the sclera, the choroid and the retina. The eyeball is filled with a clear substance called vitreous body. It holds the lens, which is located between the anterior chamber and the posterior chamber. At the front of the eye are the conjunctiva and cornea. Under the cornea is the iris, which covers the lens. Depending on the available light and whether it is bright or dark, the iris contracts or expands, adjusting the size of the pupil to control the amount of light entering the eye. Like the aperture of a camera, the eye adapts to light and adjusts its depth of field.
How do we see?
Light falls on the cornea, then on the pupil, then on the lens and then passes through the vitreous body to the retina. From here, sensory cells and neurons process the optical information and transmit it to the brain. Located directly behind the retina is the choroid, which nourishes the retina. The retina contains millions of light-sensitive sensory cells, called photoreceptors. When light hits these receptors, they convert the optical stimulus into an electrical signal that the optic nerve then transmits to the brain. Only at this point does an image emerge – the image that we see. Photoreceptors are grouped into rods and cones. Rods enable us to see monochrome images in low-light conditions. The cones enable us to see in colour. These sensory cells are located close to the macula, which is sometimes referred to as the yellow spot. This area processes the finest details for highest visual acuity. Our visual field has a radius of about 180 degrees, so that we can also see movements and objects to our sides, using what is called our peripheral vision.
Common eye complaints
Our eyes must constantly protect themselves from external irritants. Dust and pathogens, for instance, are wiped away with the help of our eyelid when it blinks. Draughts and overheated or air-conditioned rooms often cause the surface of the eye to dry out. Extended work at a computer can also cause the conjunctiva to become dry. When we stare at a computer screen, we do not blink as often as we do otherwise, which leads to a loss of moisture in the eye. This can mean irritation, redness and excessive tears as a result of the disruption to the tear film, and even eye infection. Sun, wind and dry heat can also irritate the eyes. Cycling or swimming in indoor or outdoor swimming pools can also cause watery, red eyes. Frequent eye complaints include conjunctivitis, dry eyes and styes. In conjunctivitis, a distinction is made between non-infectious and infectious forms, the latter of which are usually caused by bacteria.
Effective treatment of eye diseases
Some eye ailments can be treated effectively and usually heal without complications. These include conjunctivitis, dry eye and styes. Each of these conditions has different symptoms, and their recommended treatment often includes the use of eye drops or eye ointment. Eye disorders should always be checked by a doctor. A rule of thumb is that if symptoms last longer than two days, call the doctor. Also consult a doctor if there is severe pain in the eye area, sudden loss of vision, or persistent or unclear symptoms.
How to prevent eye discomfort
We are often unaware of just how much we use our eyes. Computer work and overstimulation as well as dry air, dust and allergens, not to mention sun and wind can irritate the eyes. To counteract these possible irritants, take a few minutes every day for an eye workout. Short exercises help relieve eye strain. A balanced diet, regular exercise and fresh air are also important for overall health.