8/31/2023 0 Comments Double pupil wikipediaThe visual distortion experienced by the person comes from two sources, one being the irregular deformation of the surface of the cornea, and the other being scarring that occurs on its exposed highpoints. The predominant optical aberration of the eye in keratoconus is coma. Some even notice the images moving relative to one another in time with their heartbeat. People also commonly notice streaking and flaring distortion around light sources. This pattern does not typically change from day to day, but over time, it often takes on new forms. Instead of seeing just one point, a person with keratoconus sees many images of the point, spread out in a chaotic pattern. This effect is most clearly seen with a high contrast field, such as a point of light on a dark background. The classic symptom of keratoconus is the perception of multiple "ghost" images, known as monocular polyopia. Multiple images made by extremely high contrast light sources as seen by a person with keratoconus It may cause luminous objects to appear as cylindrical pipes with the same intensity at all points. Some develop photophobia (sensitivity to bright light), eye strain from squinting in order to read, or itching in the eye, but there is normally little or no sensation of pain. The disease is often bilateral, though asymmetrical. Some individuals have vision in one eye that is markedly worse than the other eye. Visual acuity becomes impaired at all distances, and night vision is often poor. As the disease progresses, vision deteriorates, sometimes rapidly due to irregular astigmatism. At early stages, the symptoms of keratoconus may be no different from those of any other refractive defect of the eye. People with early keratoconus often notice a minor blurring or distortion of their vision, as well as an increased sensitivity to light, and visit their clinician seeking corrective lenses for reading or driving. ". a candle, when looked at, appears like a number of lights, confusedly running into one another" - Nottingham Signs and symptoms Simulation of the multiple images seen by a person with keratoconus. The word is from the Greek kéras meaning cornea and the Latin cōnus meaning cone. While it occurs in all populations it may be more frequent in certain ethnic groups such as those of Asian descent. It occurs most commonly in late childhood to early adulthood. However, some estimates suggest that the incidence may be as high as 1 in 400 individuals. Keratoconus affects about 1 in 2,000 people. In some cases, when the cornea becomes dangerously thin or when sufficient vision can no longer be achieved by contact lenses due to steepening of the cornea, scarring or lens intolerance, corneal cross-linking is not an option and a corneal transplant may be required. In 2016, the FDA approved corneal collagen cross-linking to halt the progression of keratoconus. In most people the disease stabilizes after a few years without severe vision problems. As the disease progresses, special contact lenses (such as scleral contact lenses) may be required. Initially the condition can typically be corrected with glasses or soft contact lenses. Keratoconus causes very distinctive changes in the appearance of these maps, which allows doctors to make the diagnosis. Topography measures the curvature of the cornea and creates a colored "map" of the cornea. The underlying mechanism involves changes of the cornea to a cone shape. Proposed environmental factors include rubbing the eyes and allergies. Patients with a parent, sibling, or child who has keratoconus have 15 to 67 times higher risk in developing corneal ectasia compared to patients with no affected relatives. While the cause is unknown, it is believed to occur due to a combination of genetic, environmental, and hormonal factors. In more severe cases a scarring or a circle may be seen within the cornea. This may result in blurry vision, double vision, nearsightedness, irregular astigmatism, and light sensitivity leading to poor quality-of-life. Keratoconus ( KC) is a disorder of the eye that results in progressive thinning of the cornea. Blurry vision, nearsightedness, light sensitivity
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