Cataract. Causes, symptoms and diagnostics
Cataract. Causes, symptoms and diagnostics
Cataract is partial or complete blurring of the crystalline lens which lies in the eye between the iris and the vitreous body. The lens is transparant and serves to refract the light to focus it on the retina. The lens affected by cataract loses its transparency and no longer refracts light, as a result, the vision gradually worsens and can be lost altogether.
Causes of cataract and risk groups
The following groups may be affected by cataract:
- elderly people – age-related cataract (90% of all cases);
- people recovering from injuries – injury cataract (4%);
- after radiation – radiation cataract (3%);
- in newborns – congenital cataract (3%).
Cataract can also be triggered by hormonal disorders (metabolism disorders, diabetes), lack of vitamins in the diet, some eye disorders, adverse environmental conditions, prolonged administration of medications. Latest research shows that chain smoking can also trigger cataract.
Cataract in elderly people
Age-related cataract is the most common variety. According to the data of World Health Organization, 70 to 80% of all cases of cataract affect people above 70. Cataract is commonly thought of as a disease of the elderly. However, it is not a completely correct view. Age-related cataract develops due to the aging of the body; as everyone ages at their own pace, so cataract may affect not only elderly people, but even active people aged 45 to 50. Sometimes age-related cataract is called old age cataract, however, the latter is not a correct term as of now.
The main cause of age-related cataract is the change of the lens biochemistry due to aging. Blurring of the lens is quite natural in terms of functional condition of the body, therefore, anyone can be affected by this condition.
Symptoms and signs of cataract
The ancient Greeks called cataract “waterfall”, or kataraktes. One’s vision gets blurry, almost like through a steamy glass. This is the main evidence of cataract which means that the blurring has spread to the center of the lens and requires surgical intervention.
What can you do if you suspect that you or your relatives have cataract?
Make an appointment for diagnostics with Excimer!!
We will correctly diagnose your condition and prescribe suitable treatment.
How quickly does cataract ripen?
In patients with age-related cataract, the lens clouds gradually, sometimes it may take from 4 to 15 years to become completely clouded. At the initial stage, only the periphery of the lens may be clouded without affecting the optical area and vision, as a result. Later the pathology spreads to the center and reduces the transmission of light which causes dramatic reduction of vision. When the cataract is overripe, visual acuity reduces to just light perception. As cataract progresses, the pupil gradually changes its color from black, to greyish, then to off-white, and finally to milky white. In the latter case, cataract may be identified without special-purpose equipment.
Congenital cataract in children
Congenital cataract is one of the most common congenital eye disorders (more than half of all cases). Cataract in newborns appears due to genetic changes in the structure of proteins responsible for the lens transparency. Among possible causes of cataract in infants are diabetes of the mother, infectious diseases of the mother during the 1st trimester of pregnancy, use of some medications. The most important action in this case is to diagnose congenital cataract as early as possible. If the cataract location and size are compatible with correct development of the eye, no emergency surgical interventions are required. If the clouding prevents transmission of light to the retina and inhibits the infant’s central vision, this obstruction must be eliminated as soon as possible for proper development of the child’s visual apparatus. Excimer clinic offers treatment of congenital cataract in children as young as three months of age.
Learn more about the types of congenital cataract ▼
The most frequently occurring congenital cataracts are:
- CAPSULAR. Isolated clouding of the anterior or posterior lens capsule. The degree of vision reduction depends on the size of capsule clouding. Capsular cataract may be caused by the diseases the mother had during pregnancy or prenatal inflammations.
- POLAR. The clouding spreads both to the capsule and to the crystalline matter at the anterior and posterior poles. Bilateral cataract is the most frequent variety. Sizes and shapes may vary to affect vision differently.
- LAMELLAR (zonular). The most frequently encountered type of congenital cataract. Vast majority of the cases are bilateral. Located in the center, forms around a clear (or slightly blurry) nucleus. Always brings about reduction of vision, often dramatic – up to 0,1 D and lower.
- NUCLEAR. Affects both eyes, generally hereditary, in most of the cases leads to reduction of vision to as low as - 0,1 D. If the clouding is limited to the germinal nucleus, reduction of vision may be slight or may not even occur.
- COMPLETE. Generally, a bilateral condition. Clinical aspects vary and depend on the degree of lens blurring. In case of the complete cataract, the whole of the lens is clouded. The child is blind, with only light perception retained. The condition may be prenatal or developed during the first months of life. Complete cataract is comorbid with other developmental eye disorders (microphthalmia, choroidal coloboma, macular hypoplasia, nystagmus, strabismus, etc). Complete cataract sometimes tends to disperse and leave a membrane around the pupil, i.e. transfers to the phase of membranous cataract.
- COMPLICATED. May be caused by galactosemia, diabetes, viral rubeola and other severe conditions. Often comorbid with other congenital defects (congenital heart disorders, deafness).
The most important action in this case is to diagnose congenital cataract as early as possible. If the cataract location and size are compatible with correct development of the eye, no emergency surgical interventions are required. If the clouding prevents transmission of light to the retina and inhibits the infant’s central vision, this obstruction must be eliminated as soon as possible for proper development of the child’s visual apparatus. Excimer clinic offers treatment of congenital cataract in children as young as three months of age.
Lens clouding is irreversible!
Do not wait till the cataract ripens, don’t lose your time and vision! Doctors recommend starting treatment of cataract as soon as it inhibits normal vision.
At Excimer, we use state-of-the-art diagnostic equipment and methods to identify cataract even at the earliest phases. At the initial stage of cataract, a person may not even suspect that he or she is affected, however, biochemical processes are active, the lens gradually loses transparency, and as a result, a person loses his or her eyesight. Many mistake cataract for another age-related condition with similar symptoms but different origin, i.e. age-related farsightedness. Only a professional ophthalmologist is able to diagnose this conditions using special-purpose devices. The main method of cataract diagnostics is biomicroscopy of the eye, or examination using slit lamp. Other important auxiliary methods are visual acuity evaluation, fundoscopy, fields of vision examination, measurement of intraocular pressure. Before surgeries, we use a cutting-edge IOL Master optical coherent biometer by Zeiss to calculate optical parameters.
The only effective method of cataract extraction is surgical intervention to replace a clouded lens with a clear lens implant, the characteristics of which are as similar to the natural one as they can be. Excimer uses the most advanced methods for cataract treatment, i.e. ultrasound cataract phacoemulsification, including auxiliary femto laser assistance.
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