Apart from their name “Star”, these two clinical pictures have nothing in common. In the case of cataracts , the lens of the eye gradually becomes cloudier with increasing age, leading to blindness. Glaucoma , on the other hand , is the collective term for a number of similar eye diseases with damage to the optic nerve and the field of vision.
Diagnosis: glaucoma and cataract
The cataract can be recognized by the increasing opacity in the pupillary plane. The ophthalmologist determines the remaining visual acuity and checks whether the lens opacity affects the optical center of the lens. In the so-called slit lamp and subsequent eye fundus examination, the cornea and especially the retina are also assessed.
Glaucoma is usually discovered during a glaucoma check (every two years from the age of 40). The ophthalmologist measures the intraocular pressure, looks at the optic nerve head or the fundus of the eye and, if necessary, checks the field of vision.
Symptoms, Signs, Ailments
With cataracts, the perceived image gradually becomes blurred, dull, and slightly hazy. Colors fade and yellow and there may be double vision in one eye. Other symptoms are:
- increased sensitivity to glare, especially in bright sunlight, driving at night and on wet roads
- frequent changing of prescription glasses
Glaucoma, on the other hand, usually does not cause any noticeable symptoms if the intraocular pressure is only slightly to moderately high (exception: glaucoma attack). Colored rings or halos around light sources can only appear if the intraocular pressure is high. If left untreated, the visual field defects progress to blindness.
Causes and risk factors
Cataracts occur with age. The following factors, among others, can promote the occurrence of lens opacity:
- strong exposure to light
- disturbed lens nutrition
- General diseases such as diabetes mellitus and neurodermatitis
- years of cortisone use
- inflammation inside the eye
- eye injuries
- Green Star
- eye surgeries
The risk factors for glaucoma are:
- increased intraocular pressure
- the age
- familial genetic load
- Myopia from minus five dioptres
- strong farsightedness
- low blood pressure
- Use of cortisone preparations
In some glaucoma patients, the optic nerve already reacts hypersensitively to completely normal intraocular pressure values (16 mmHg and 21 mmHg).
Cataracts and glaucoma: therapy and course
Cataracts can currently only be treated surgically. In about 95 percent of those who have been operated on, the sight is completely restored, in the remaining five percent it is at least partially restored. During the approximately 20-minute operation, the body’s own cloudy lens is replaced with an artificial lens (intraocular lens). Examples of intraocular lenses that can be considered are monofocal lenses (enabling sharp vision near or far), multifocal lenses (relatively sharp vision at all distances, but somewhat reduced contrast vision) and special lenses. Weeks to months, sometimes even years, after successful cataract surgery, an easily removable secondary cataract can appear.
In the case of glaucoma, the intraocular pressure must be lowered (sometimes below the normal values) in order to prevent further damage to the optic nerve: the pressure is usually lowered with eye drops that are used consistently throughout life, which reduce the production of aqueous humor. Attention: allergies and intolerances can occur. In about three to five percent of those affected, the drainage of the aqueous humor has to be facilitated surgically or with a laser.
