On this page you find the most important terms related to cataracts, astigmatism, and many other eye diseases and eyes in general.
The near and far adjustment of the eye by changing the shape of the lens is called accommodation. With a changed curvature, objects can be seen clearly either near, in the intermediate range or in the distance. The decreasing elasticity of the lens causes presbyopia from around the age of 45 onwards because the lens can no longer focus well up close.
The difference between the distance and near value (also reading value) indicates the amount of addition. It is given in diopters and is always positive, measured in 0.25 increments. The value is usually the same for both eyes.
Metabolic processes and uncontrolled cell growth lead to progressive destruction of the macula. Age-related macular degeneration is painless but causes a loss of central vision.
With astigmatism, the cornea is not perfectly spherically shaped but has bends on the surface. As a result, incoming light is not optimally refracted by the lens and projected at one point on the retina but is instead distorted. Resulting in an inaccurate image on the retina. Astigmatism is corrected with glasses or implantable artificial lenses by means of refractive surgery.
The capsular bag holds the lens in its position so that it is centrally oriented towards the light. During cataract surgery, the capsular bag is opened in a circular manner, the body’s own lens is crushed and removed. Afterwards, the surgeon inserts the previously selected intraocular lens.
Cataracts are an age-related eye disease that usually occurs because of presbyopia. Over time the natural lens of the eye becomes cloudier, and the quality of vision deteriorates. Those affected often notice an increased sensitivity to glare in the dark. Reduced contrast vision, a yellowish veil and a generally declining quality of vision are more symptoms of cataracts. Surgery in which the natural lens of the eye is removed and replaced with an artificial intraocular lens is the only feasible treatment option.
The ciliary muscle ensures the accommodation of the eye, i.e. that the lens of the eye changes its refractive power and the eye can therefore adjust to different distances. Accommodation is a skill that the human eye is most capable of, especially at a young age.
During refractive lens exchange, the body’s own lens is removed and replaced with an artificial intraocular lens. This surgical procedure is used to correct visual defects, refractive errors, particularly near-sightedness, farsightedness, and astigmatism. This procedure is chosen by patients who wish more independence from glasses.
The cornea consists of 5 cell layers and is the outermost part of the eye serving as a barrier to the outside. It is responsible for most of the refraction of light entering the human eye. It is kept moist and transparent by the tear film.
Diopters indicate the refractive power of a lens. If the eye is nearsighted, the diopter value is negative, indicated by a minus sign; if it is farsighted, there is a plus sign. Diopters are given in increments of 0.25.
Glaucoma is an irreversible eye disease caused by increased intraocular pressure. This damages the optical nerve and thus leads to a deterioration in the quality of vision. The disease can be treated with medication or surgery.
Haptics are elastic juts that are placed on an artificial lens’ edge to optimize its anchoring in the capsular bag or sulcus.
With a farsighted eye, the eyeball is too short. The focal point is not on the retina, but a little behind it. If you increase the distance to an object, the image becomes sharp with farsightedness. Farsighted people therefore sometimes hold books or cell phones with their arm outstretched.
(Surgical) insertion of medical devices into the body.
Intraocular lenses are acrylic artificial lenses that are inserted during surgery to replace the body’s own natural lens. A distinction is made between posterior and anterior chamber lenses, hydrophilic and hydrophobic lenses, and foldable and rigid lenses.
The iris gives the eye its colour. It controls the pupil (aperture), which can enlarge and shrink.
The macula, also known as the yellow spot, is the area of sharpest vision. It is the area of the human retina with the highest density of photoreceptor cells.
Monofocal lenses are used as standard in cataract surgery. They replace the natural lens and allow sharp vision near or far. Glasses must be worn for all other distances.
Multifocal lenses can be used in cataract surgery and come closest to natural vision. They replace the natural lens and allow sharp vision in near, in the intermediate and far distances.
In a short-sighted eye, the eyeball is too long. The focal point is not on the retina, but a little bit in front of it. If you reduce the distance to an object, the image becomes sharp in the case of shortsightedness.
Ophthalmology is a clinical and surgical specialty within medicine that deals with the diagnosis and treatment of eye disorders.
This procedure is used in cataract surgery. The natural lens is broken up using ultrasound and then sucked out. The artificial intraocular lens is then implanted into the eye.
In addition to so-called standard lenses (monofocal lenses), premium lenses or lenses with additional benefits are available. These lenses can correct visual impairments such as shortsightedness, farsightedness, presbyopia, or astigmatism. Depending on the results of the eye examination and furthermore, taking personal living circumstances into account, such more individualized lenses can be a great relief in everyday life.
The natural lens of the eye loses elasticity with age, making it increasingly difficult to focus on near distances. Presbyopia usually occurs from the age of 45 and is usually corrected with reading glasses. There are various modern methods for a permanent solution, such as laser procedures or the implantation of multifocal intraocular lenses.
Progressive lenses have special progressive lenses that correct different visual defects at near and far distances, as well as presbyopia. This allows the wearer to perceive the environment in a smooth transition.
After cataract surgery, secondary cataracts can occur. The lens capsule becomes cloudy, but this can be easily and quickly treated with a YAG laser.
Shortsightedness, farsightedness, presbyopia and astigmatism are refractive errors that prevent a sharp image from being created. Shortsighted people have problems seeing clearly in the distance, while longsighted people and presbyopia have difficulty seeing up close. With astigmatism, the image appears distorted.
Visual defects can be corrected with glasses, implantable contact lenses, intraocular lenses, or laser surgery.
The retina consists of nerve tissue and is used to perceive light stimuli. It forms the innermost layer of the eyeball and extends from the outer edge of the pupil to the optic nerve. Its sensory receptors, rods and cones, are used to capture images.
The sulcus is a groove between the capsular bag and the anterior chamber of the eye. It is largely formed and limited by the ciliary muscles.
