Glossary
Accommodation
The eye’s ability to sharply switch focus between objects in the distance and close up unaided. The age-related loss of this ability from around age 45 is called presbyopiaG. The patient needs reading glasses.
Addition (= ADD)
The addition is given in dioptresG and results from the regular visual defect (hyperopia or myopia)G and presbyopiaG. The addition is the value that must be added to the existing defective vision in order to be able to see sharply again at close range.
Age-related macular degeneration (AMD)
In macular degeneration, the eye’s central sharpness of vision is lost either partially or in full. In industrial countries, AMD is the primary cause of blindness in over 50s.
Aphakia
This is the lack of an eye lens, caused by surgical removal or injury.
Astigmatism
The eye’s cornea is not an even sphere, rather has various bumps and dips in different directions. Objects are perceived as lines rather than dots. Astigmatism can be corrected with glasses, contact lenses or surgery.
Capsular bag
‘Lens shell’ / position of natural lens. This is where the intraocular lens is positioned.
Cataract
Clouding of the eye’s lens as a result of natural aging, medication or injury to the eye.
Ciliary muscle
Muscle on the ciliary body that impacts accommodationG (the eye’s ability to sharply focus on objects both near and far away). Contraction reduces the strain on the zonular fibres, so the young lens arches more to develop stronger refraction. These muscles get weaker as we age.
Cornea
This forms the frontal, completely clear part of the external uvea. It is around 11mm to 12mm in diameter, and 0.5mm to 0.6mm in thickness in the centre.
Dioptre
Unit of measure for the refractive power of a lens. If the eye is short-sighted, the dioptre value of the glasses or contact lenses will be negative.
Clear Lens Exchange (= RLE – refractive lens exchange)
In refractive lens exchange, the body‘s own lens is replaced by an artificial lens. Since the eye thereby loses its natural ability to focus itself at different distances, this procedure is only used when the accommodation abilityG is reduced. A healthy lens normally is not replaced.
Glaucoma
Disease whereby the optic nerve is damaged by increased pressure inside the eye.
Haptics
External stretchy extensions of the intraocular lensG used to anchor the lens into the capsular bag or sulcusG.
Hyperopia (= long-sightedness)
Visual disorder: sharp distance vision, unclear near vision.
Implantation
(Surgical) insertion of foreign bodies into the body.
Intraocular lens (IOL)
Artificial lenses used in cataract surgery to replace the body’s own lens inside the eye, in the capsular bagG. There is a difference between posterior-chamber and anterior-chamber lenses, collapsible lenses (made from acrylic or silicone) and rigid lenses (made from PMMAG/Plexiglas). Modern cataract lenses, such as the LENTIS Comfort, meet the desire for freedom from glasses in everyday situations, such as working at a computer.
IOL
Short for intraocular lens
Iris
The coloured skin that gives the eye its colour. It controls the pupil, which can expand and contract.
Macula
Area of the human retina with the greatest density of visual cells. This is the location of the sharpest vision.
Monofocal lens
The monofocal lens is the standard intraocular lens used in cataract surgery. These lenses are implanted into the eye and replace the natural lens. They provide either sharp near or distance vision. The patient must decide whether to continue wearing distance or reading glasses.
Multifocal lens
With multifocal lenses, vision comes closest to natural vision. They cover visual ranges from distance to near. They are implanted in the eye just like monofocal lenses and replace the natural lens.
Myopia (short-sightedness)
Visual disorder: sharp near vision, unclear distance vision.
Posterior capsule opacification
Cloudiness that may present some time after cataract treatment.
Ophthalmology
Branch of medicine dealing with the eyes.
Phacoemulsification
Cataract surgery process: the cloudy lens is liquidised or emulsified using ultrasound then aspirated.
PMMA
Polymethyl methacrylate (trade name: Plexiglas)
Premium intraocular lenses
Alongside practical standard intraocular lenses (monofocal lenses), your ophthalmologist will also offer premium lenses with tailored additional functions. Depending on medical circumstances and personal preferences, these premium lenses can correct visual disorders such as short-sightedness and long-sightedness as well as astigmatism. Premium lenses mean additional benefits – you benefit from better eyesight, exceptional comfort of vision, more independence and freedom from glasses and/or contact lenses. To put it simply, more quality of life.
Presbyopia
From around the age of 45, the ability to clearly see near visibly reduces. The eye’s lenses lose elasticity, reducing sharpness. Reading glasses are required.
Refraction issues
In the case of a refraction issue, light rays meet the eye at varying degrees of refraction, causing a visual disorder. This must be corrected with visual aids or modern intraocular lenses.
Retina
Layer of specialised nerve tissue on the back of the inside of the eye. It has sensory receptors (rods and cones) to perceive images.
Sulcus ciliaris (= the sulcus of the ciliaris)
Indentation between the iris and the ciliaris, in front of the capsular bagG.
Varifocal glasses
Varifocal glasses correct all distances from distance to near in a gliding transition.
GTerm also explained separately in the glossary.
