Cataract (from the Greek word “katarrhaktes” which means “waterfall”) is opacity or discoloration of a part or the entire lens, leading to a decrease in its light conductivity and decrease in visual acuity.
According to the WHO, half of the cases of blindness in the world are conditioned by cataract. In the age group of 50-60 years old, cataract is detected in 15% of the population, 70-80 years old ‒ in 26%-46%, over 80 years old ‒ in almost everyone.
What concerns congenital eye diseases, cataract also takes a leading position. The high prevalence of the disease and its social consequences make cataract one of the most urgent problems of modern ophthalmology.
The lens is part of the dioptric (light conductive and light refractive) apparatus of the eye, located behind the iris, opposite the pupil. Structurally, the lens includes a capsule (a bag), the capsular epithelium and the lens substance. The surface of the lens (the front and the back) has a spherical shape with a different radius of curvature. The diameter of the lens is 9-10 mm. The lens is an avascular epithelial mass; nutrients enter it by means of diffusion from the surrounding intraocular fluid.
According to its optical properties, the lens is a biological convexo-convex transparent lens, the function of which is to refract the rays within it and focus them on the retina of the eye. The refractive power of the lens is dissimilar in thickness and depends on the state of accommodation (in a resting state ‒ 19.11 dioptre; in a state of tension ‒ 33.06 dioptre).
Any change in the shape, size and position of the lens leads to a significant disturbance of its functions. The anomalies and pathology of the lens are aphakia (the absence of the lens), microphakia (a smaller size), coloboma (the absence of a part of the lens and its deformity), lenticonus (protrusion of the surface in the form of a cone) and cataract. Cataract formation can occur in any of the layers of the lens.
The normal functioning of the lens is maintained for as long as the percentage balance of the substances that make up the lens is kept. The cataractogenic process is characterized by numerous biochemical factors ‒ a change in the amount of water entering into the lens composition, potassium loss, an increase in the calcium level, a decrease in the amount of oxygen and ascorbic acid, as well as glutathione and hexose. The transparency of the optical lens of the eye ensures the water solubility of proteins within its structure. With age, the processes of chemical oxidation of the membrane substances begin to dominate in the lens of the eye, which in turn leads to the self-destruction of proteins. Therefore, proteins gradually turn from water-soluble into water-insoluble.
This chain of pathological processes leads to the loss of transparency of the lens, that is, to its opacity. Lenticular opacity is a response from the lens substance to a variety of unfavourable factors or modification of the components that make up the intraocular fluid, which is the medium surrounding the lens.
There are several degrees of cataract and, depending on the degree, the symptoms will vary. However, the main ones are:
- The occurrence of double vision in the eye in the case when the second eye is closed at this time. It is an early symptom. As the disease progresses, it disappears.
- Blurred images, which is not corrected by contact lenses and glasses. At the same time, both close and distant objects are poorly visible. Patients describe such vision as dimmed, with the formation of a cloud.
- The appearance of flashes and patches of light, occurring mainly at night.
- Increased photosensitivity of the eye at night. In general, night vision is becoming worse. All sources of light seem to the patient far too bright, irritating the eyes.
- When looking at light sources, a person with a cataract sees halos around it. People with lenticular opacity are not able to drive a car, or they have difficulty in doing it, as they are blinded by the headlights of the oncoming traffic.
- Perception of color is impaired, they all become paler. It is especially difficult for a person to perceive shades of purple and blue.
- Improved vision, which is temporary. This symptom is characterized by the fact that a person wearing glasses with the progression of the disease may give up them. However, this time period is short and the vision will begin deteriorating again.
- If a person needs to change glasses for vision frequently, there is some reason to think about a cataract, as this disease tends to progress and quickly reduce visual acuity.
Cataract symptoms are the appearance of stripes and flickering spots or various balls. Ancient Greeks called this disease a waterfall, because with a cataract people get the feeling that their eyes are covered with a veil, as if they look through misted glass.
When the cataract occurs, it is difficult to read, write and work with small details. As the cataract “matures”, the coloor of the pupil becomes white instead of black.
The first factor that makes it possible for a doctor to suspect that the person has a cataract is the patient’s age of over 60 years old. In this case, the clinical picture has characteristic features. During examination an ophthalmologist observes opacities that can be located in different parts of the eye ‒ in the peripheral part of the lens or opposite the pupil. The opacities are greyish, sometimes with a white hue.
Depending on the type of the cataract, the ophthalmologist will observe a diverse clinical picture, accompanied by the following signs:
- An anterior cataract declares itself as a white spot with clearly defined boundaries. When the cataract is set a little forward and is pointed, it is called anterior pyramidal.
- If the opacity is located at the posterior pole of the lens and looks like a white round ball, it is referred to as a posterior polar cataract.
- A central cataract is detected by the following features ‒ a spherical shape, the location in the centre of the lens, 2 mm in diameter.
- A fusiform cataract is identified by its shape. Such opacity shows in the form of a thin spindle. It is located along the entire length of the lens.
- A zonular congenital cataract has the appearance of a turbid nucleus with transparent layers.
- The clouding of the entire lens, the liquefaction of its masses and the further formation of a dense bag are signs of a dense, soft cataract.
- A diabetic cataract is characterized by the appearance of white opacities in the form of flakes. They are located on the entire surface of the lens, often changing the iris.
- A tetanic cataract is characterized by the same signs as its diabetic variety and is detected by the signs of the disease that caused it (parathyroid hypofunction).
- A toxic cataract most often declares itself in the form of opacities located under the lens capsule, with subsequent spread to the cortical layers.
- A senile cataract has a lot of signs, and it depends on the degree of the disease progression ‒ initial, swelling, mature and hypermature.
These are the most common signs that help to detect a cataract and reckon its particular type.
There are several factors that determine the etiology of the onset and progression of a cataract. They are as follows:
- Diabetes mellitus, leading to the development of a diabetic cataract and other diseases of the thyroid gland. In particular, titania, muscular dystrophy and others.
- Smoking and long-term alcohol abuse.
- Eye injury.
- Intake of medications belonging to the class of corticosteroids.
- Prolonged exposure of the eyeball to sunlight.
- The person’s age. The older the person gets, the lower is the body’s ability to resist toxins from the external environment. In addition, the level of the antioxidants provided by nature is reduced.
- Retinal detachment, iridocyclitis, chorioretinitis, Fuchs syndrome, glaucoma, and some other diseases lead to impaired lens metabolism and cataracts.
- Severe infections, such as malaria, typhoid, smallpox and others.
- Poisoning of the body, in particular with thallium, naphthalene and other toxic substances.
- Skin diseases, which include eczema, Jacobi poikiloderma, scleroderma, neurodermatitis.
- Eye burns.
- Myopia alta.
- It is impossible to exclude a hereditary factor.
- Down syndrome.
- Congenital cataracts often occur against the background of the fact that the pregnant woman has suffered severe infections, such as rubella, toxoplasmosis, influenza, etc.
- Work in hot workshops where the risk of eye radiation exposure is high.
According to some sources, the disease has become the cause of blindness for more than 20,000,000 people in the world.
Poor ecology, poisoning with various toxic drugs, ultraviolet or radiation exposure, as well as microwave and smoking can also be causes of cataracts.
In ophthalmology cataracts are divided into two large groups ‒ congenital and evoked. Congenital cataracts, as a rule, are limited in size and are stationary (not progressing). With evoked cataracts changes in the lens progress.
Depending on the etiology, evoked cataracts are senile (age-related ‒ about 70%), complicated (with eye diseases ‒ about 20%), traumatic (with eye injuries), radiation (with X-ray, radiation, infrared radiation damage to the lens), toxic (with chemical and medicinal intoxications), cataracts linked with systemic diseases.
According to the localization of the opacity in the lens, there are:
- Anterior polar cataracts ‒ located under the capsule in the anterior pole of the lens; the opacity is in the form of a whitish and greyish round spot;
- posterior polar cataracts ‒ located under the capsule in the posterior pole of the lens; similar in color and shape to the anterior polar cataract;
- fusiform cataracts ‒ located on the anteroposterior axis of the lens; have the shape of a spindle, in appearance resemble a thin grey tape;
- nuclear cataracts ‒ located in the centre of the lens;
- lamellar (zonular) cataracts ‒ located around the nucleus of the lens, the turbid and transparent layers alternate;
- cortical cataracts ‒ located on the outer edge of the lens; have the appearance of whitish wedge-shaped inclusions;
- posterior subcapsular cataracts ‒ located under the capsule behind the lens;
- complete (total) cataracts ‒ always bilateral, characterized by clouding of the whole substance and the lens capsule.
Congenital cataracts can be of any of these morphological forms, while evoked cataracts can be nuclear, cortical and complete.
This type of the eye disease is a consequence of the natural decrepitude of the body. In the initial stage of the immature cataract, objects gradually lose their clear outlines. As the disease progresses, dark dots and spots float before the eyes, images can often appear double. Near vision becomes problematic. As the cataract matures, the pupil of the eye becomes white. With a nuclear cataract, the focus of the opacity forms in the centre of the lens, acquiring a brown color. Gradual induration of the nucleus leads to high level of myopia.
The age-related cataract progresses faster if there are primary eye diseases that provoked its development. Hereditary predisposition can affect. Sometimes injuries of the eye, mechanical or chemical, become the cause of cataracts in old age. There is a high risk of this disease in diabetics, as well as in heavy smokers. In these cases cataracts are often found after the age of 55.
In its maturation, a cataract goes through 4 stages:
- hyper-mature cataract.
In the initial stage of cataract maturation, the lens hydration takes place, which is characterized by the accumulation of excess fluid between the fibres of the cortical layer with the formation of the so-called “water fissures”. The opacities in the initial stage are localized in the cortex, on the periphery, outside the optical zone of the lens, and therefore do not affect visual acuity.
The stage of the immature cataract is characterized by the progression of the opacities that affect the central optical zone of the lens. Biomicroscopic examination reveals lens opacities that alternate with transparent areas. In this stage of cataract maturation, an appreciable decrease in visual acuity is observed.
In the stage of the mature cataract, induration and complete clouding of the lens substance is observed. The lens nucleus and its posterior cortical layers are not visible during biomicroscopy. An external examination reveals a pupil of a milky-white or grey color. Visual acuity with mature cataracts varies from 0.1-0.2 to the level of light perception.
In the stage of the hyper-mature cataract, the disintegration of the lens fibres, the liquefaction of the lens cortex and the capsule shrinkage occur. The cortex becomes a homogeneous milky white shade. The nucleus, having lost its support, goes down. The lens becomes like a bag filled with a cloudy liquid, with a nucleus at the bottom. This hyper-mature cataract is called the Morgagnian cataract. This stage corresponds to complete blindness.
The hyper-mature cataract can be complicated by phacogenic (phacolytic) glaucoma, bound with the clogging of the intraocular fluid outflow natural pathways by macrophages and protein molecules. In some cases, a rupture of the lens capsule can occur with the release of protein detritus into the eye cavity, which leads to the development of phacolytic iridocyclitis.
Cataract maturation can be rapidly progressive, slowly progressive and moderately progressive. In the first case, 4-6 years pass from the initial stage to the extensive clouding of the lens. Rapidly progressive cataracts develop in approximately 12% of cases. Slowly progressive cataracts mature within 10-15 years and occur in 15% of patients. Moderately progressive cataracts mature within the period of 6-10 years and occur in 70% of cases.
Congenital cataracts account for more than half of all congenital defects of the organ of vision. A cataract in newborns is caused by genetic changes in the structure of proteins necessary to ensure the transparency of the lens. Causes of cataract in children under one year of age can be diabetes in the mother, infectious diseases in the first trimester of pregnancy, the intake of certain medications.
The main thing in this case is the early diagnosis of congenital cataracts. If the localization and size of the opacities in the lens do not interfere with the proper development of the organ of vision, such a cataract does not require emergency surgical treatment. If the opacity prevents the light from reaching the retina and hampers the development of the central vision in the infant, it is necessary to remove this obstacle as soon as possible so that the child’s visual system can develop properly. The treatment of congenital cataracts is carried out even in very young children, starting from the age of three months.
Of the congenital cataracts the most common are:
- Capsular. Isolated opacity of the anterior or posterior bag (capsule) of the lens. The degree of vision loss depends on the size of the opacities of the capsule. The occurrence of capsular cataracts can be caused by the mother’s diseases during pregnancy or intrauterine inflammatory processes.
- Polar. The lesion extends both to the capsule and to the lens substance at the anterior or posterior poles. In most cases, bilateral cataract occurs. Size and shape vary considerably, which determines its effect on vision.
- Lamellar (zonular). The most common form of the congenital cataract. In most cases, it is bilateral. It is located in the centre, around the transparent (or slightly hazy) nucleus. Vision is always reduced, often very significantly, to 0.1 and below.
- Nuclear. It develops in both eyes and is of a marked heredofamilial character. Most often the vision decreases to a very low level ‒ 0.1 and below. In cases where the opacity is limited to the embryonic nucleus, vision may decrease slightly or not at all.
- Complete. The disease is usually bilateral. The clinical picture is diverse and depends on the degree of the lenticular opacity. With a complete cataract, the entire lens is cloudy. The child is blind and has only a light sense. The cataract may develop before birth or mature in the first months of life. The complete cataract is combined with other defects in eye development (microphthalmos, choriodal coloboma, yellow spot hypoplasia, nystagmus, strabismus, etc.). The complete cataract can sometimes have a tendency to resorption, and then a membranous cataract remains in the area of the pupil.
- Complicated. The cause of its development can be galactosemia, diabetes, viral rubella and other serious diseases. It is often accompanied by other birth defects (heart defects, deafness).
If the cataract is not diagnosed in time and not treated, it can lead to such complications as:
- Complete blindness or amaurosis. It is the cataract that takes the first place among the diseases leading to absolute loss of vision. At the same time, blindness does not come abruptly, it impends gradually. If treatment is started in time, this complication can be avoided. Amaurosis is diagnosed when vision is completely lost.
- Dislocation of the lens. This complication is characterized by the fact that it is completely displaced and detached from the ligament holding it. Vision at the same time dramatically worsens, and the lens itself must be removed.
- Phacolytic iridocyclitis, which declares itself with inflammation of the ciliary body and iris. The person experiences severe pain in the eye and head, the vascular reticulum becomes bluish or red, the pupil moves poorly. When the acute process is eliminated, there arises a question of removing the lens.
- Phacogenic glaucoma is characterized by a secondary increase in pressure inside the eye due to the fact that the lens increases in size. The lens requires removal, and therapy aimed at reducing the pressure is performed.
- Obstructive amblyopia. This complication often occurs in children and becomes a consequence of congenital cataracts. It is characterized by the fact that the retina, which does not receive signals from the outside, atrophies and ceases to function, although it has been healthy before. The treatment of this complication is only surgical.
To avoid such terrible complications, the disease must be diagnosed and treated in time under the guidance of professional doctors. You should consult a specialist as soon as the first symptoms become apparent.
Detecting a cataract in the patient’s eye is not particularly difficult. Difficulties arise when the ophthalmologist is faced with the task of determining the stage, the localization, the etiology of the opacity and, most importantly, establishing the necessary scope and approach of surgical intervention. Difficult diagnosis of a cataract is explained by the fact that pronounced opacities in the lens make it very difficult, and sometimes impossible, to examine the condition immediately behind the lens, as well as the vitreous body and the retina.
All the methods of examining a patient with a cataract can be divided into four large groups:
- Standard (routine) methods, mandatory for each patient:
- Visometry ‒ estimation of visual acuity.
- Estimation of binocular vision ‒ assessment of three-dimensional, stereoscopic vision with both eyes at the same time.
- Perimetry ‒ assessment of visual fields.
- Tonometry ‒ measurement of intraocular pressure.
- Biomicroscopy ‒ a method of microscopic examination of eye tissue that makes it possible to examine in detail the anterior and posterior segments of the eyeball, regardless of the lighting in the room. Biomicroscopy is the most important stage in the examination of a patient with a cataract, with which the ophthalmic surgeon selects the most effective method of cataract removal. Biomicroscopy is carried out by using a special device called a slit lamp. The examination is conducted under conditions of medical mydriasis (dilation of the pupil by using medications).The following characteristics are evaluated: the size and density of the nucleus, the stage of dystrophic changes in the capsule, the location of the lens, the presence of pronounced or hidden lens subluxation caused by dystrophic changes, the destruction of the ligament fibres holding the lens.
- Ophthalmoscopy ‒ a method of examining the retina, the optic nerve and the choroid in the rays of light that are reflected from the fundus of the eye. Sometimes, because of the strong opacification of the lens, the implementation of this method is difficult. At the same time, ophthalmoscopy is very informative when examining the eyes of patients with diabetes, uveitis, myopia, pigmentary retinitis.
- Gonioscopy ‒ measuring the angle of the anterior chamber of the eye. This method is crucial in determining the tactics for the surgical treatment of patients with lens pathology in combination with glaucoma.
- Additional methods, they are also required for each patient:
- Refractometry ‒ determining the refraction of the eye (the refractive power of the optical system of the eye). The method is necessary to determine the degree of hyperopia, myopia and astigmatism.
- Ophthalmometry ‒ is an eye examination with a special device ‒ an ophthalmometer. By using this device, an ophthalmologist can measure the radii of curvature of both the cornea and the lens surfaces.
- Determining the anterior and posterior size of the eyeball.
- Skiascopy ‒ the method of determining the refraction of the eye, which consists in observing the movement of shadows in the area of the pupil, while a beam of light directed at the eye is reflected from the mirror.
- Electrophysiological examination of the eye ‒ is used to assess the lability and sensitivity threshold of the optic nerve.
All the examination methods included in this group are necessary to estimate the necessary parameters of the eye, making it possible to accurately calculate the optical power of the artificial lens that will be implanted during the operation (intraocular lens). All the data is processed by using a computer, which makes possible the immediate correction of hyperopia and myopia.
- Additional methods, prescribed by the doctor:
- Ultrasound biomicroscopy
- Endothelial biomicroscopy
- Laboratory methods of examination:
- Prescribed to patients before hospitalization for surgery or directly in the hospital. Mandatory for all patients are: complete blood count and urine test, glycemia, coagulogram, blood test for HIV, hepatitis B and C, syphilis. Biochemical analysis of blood is carried out on doctor’s prescription in case the patient has associated concomitant diseases. In the case of congenital cataracts, in order to find out its etiology, the mother’s and the child’s blood serum and lens substance must be tested to detect hepatitis B virus markers.
The treatment of the initial stages of the age-related cataract is based on the use of various drugs, mainly in the form of eye drops ‒ Catachrom, Vita-Iodurol, Vitaphacol, Viceinum and a number of others. It is known that the use of these agents does not lead to the resorption of the opacities that have already formed, and at best, only slightly slows down their progression.
The main difficulty of the conservative treatment of cataracts is associated with the uncertainty of the etiology of age-related cataracts. Recently, the role of antioxidants in quenching free radicals and protecting lens proteins has been intensively studied. Research is being conducted aimed at clarifying the role of hereditary factors, environmental factors, the general condition of the body, the state of ocular hydro and hemodynamics in the progression of a cataract.
The data obtained will serve as the basis for the effective prevention and treatment of age-related cataracts.
For conservative treatment of cataracts, the so-called replacement therapy is widely used. It consists in the following: substances the lack of which is associated with the development of cataracts are injected into the body.
Vitamins (riboflavin, ascorbic acid, nicotinic acid, potassium iodide, etc.) are used especially widely. Their solutions are instilled in the conjunctival sac.
Nicotinic acid which enters into the composition of the drops, promotes the penetration of ascorbic acid into the anterior chamber of the eye. It is advisable to use these vitamins in 2-5% glucose solution, as it improves the nourishment of the lens.
Of the other drugs used as means of replacement therapy, medications that contain potassium, calcium, magnesium, glutathione, cysteine, etc. should be prescribed.
This treatment helps to completely deliver a person from a cataract, since during the operation the cloudy masses of the lens are removed. But after the cataract surgery the person cannot see, because the lens will be simply destroyed, so the mandatory second part of the surgical intervention is fitting a prosthesis that will make it possible to see.
Currently, both stages of the operation ‒ the removal of the cataract and the intraocular lens (lens prosthesis) fitting are performed during the same intervention. In other words, in one operation the person gets rid of the cataract and receives a prosthesis that makes it possible to see normally. The artificial intraocular lens which is often called an “artificial lens” has an unlimited service life. Therefore, cataract removal followed by an artificial lens fitting is considered to be a complete cure for the eye disease.
It is recommended to refrain from surgery and perform conservative treatment of cataracts in the following cases:
- The loss of vision is insignificant and gradual, as a result of which the person can well perform his or her usual duties at home and at work.
- The presence of other eye diseases, such as glaucoma and diabetic retinopathy (in this case, surgery to remove the cataract will not improve vision).
- Glasses or contact lenses help to achieve a level of vision that suits the person and makes it possible to perform ordinary household or work duties.
- The presence of severe somatic diseases with which any operations and stresses are undesirable.
Indications for Surgery
Surgery for cataracts must be performed in the following cases:
- Congenital cataract in a child (it is important to remove the cataract as early as possible so that the child can develop and not lose vision).
- Hyper-mature cataract.
- Swelling immature or mature cataract when the lens increases in size and can block the intraocular fluid outflow, causing an attack of glaucoma.
- Lens luxation or subluxation.
- An attack of secondary glaucoma, triggered by swelling of the lens.
- The need to study the fundus of the eye in the case of other diseases or for the application of laser treatments (for example, with retinal detachment, etc.).
In all other cases, the decision whether to operate a cataract or come to nothing more than conservative treatment is made by patients themselves.
Preparation for Cataract Surgery
Before the operation, each patient should go through a thorough examination of both eyes (the methods are mentioned in the section “Cataract Diagnosis”. The general condition of the whole body should also be assessed. It is necessary in order to correctly forecast the results of the operation, to prevent all sorts of complications for the operated eye and the body as a whole, as well as to determine the functional ability of the eye after the operation.
If during the examination, inflammatory processes are found in the eye, or in the organs and tissues located in the vicinity of the eye, before the operation it is mandatory to perform the inflammatory foci sanation plus anti-inflammatory therapy. Directly on the operating table, the preparation of the patient consists of instilling disinfecting drops into the operated eye, as well as drops that widen the pupil. Anesthesia depends on the type of the surgery to be performed. It may be local or general (intravenous administration of anesthetics).
Types of Cataract Surgery
Currently, the following types of operations can be performed for cataract removal:
- Intracapsular extraction of the lens ‒ the lens is removed along with the capsule through a large incision by using a special device, a cryoextractor. This technique is quite traumatic for the eye, so at present it is practically not used. Usually, an indication for such an operation is a traumatic cataract, when it is not possible to preserve the integrity of the lens capsule, or lens luxation, when the threads (chords) that suspend it are damaged.
- Extracapsular extraction of the lens ‒ during the operation the outer part of the capsule and the entire substance of the lens are removed, but the back part of the capsule is retained, which preserves the barrier between the vitreous body and the cornea. When the lens is removed, a prosthesis, an intraocular lens, is inserted and fixed instead of it. This operation is performed relatively rarely, because it is traumatic due to the large incision in the cornea and suturing. Currently, extracapsular lens extraction is being replaced by less traumatic phacoemulsification.
- Femtolaser phacoemulsification ‒ lens removal by using ultrasound. Its advantage is that the operation is performed through a micro incision from 2.2 to 5.5 mm, depending on the selected intraocular lens. The surgery is performed under local anesthesia, which makes it possible for the surgeon to maintain contact with the patient throughout the operation. There is no need for postoperative suturing. The surgery does not take more than 15 minutes. It is absolutely painless and safe. The risk of postoperative complications is minimal. The patient is quickly rehabilitated. Capacity for work is fully restored 10 days after the surgery.
- Ultrasonic phacoemulsification ‒ during the operation a special device is introduced into the anterior chamber of the eye through a small incision (1.8-3 mm), which destroys the lens substance, bringing it to the consistency of emulsion. Then this emulsion is removed through special tubes. That is, during the operation, the substance and the front part of the lens capsule are removed. The posterior lens capsule remains and acts as a barrier between the iris and the vitreous body. After the removal of the destroyed lens mass, the remaining posterior capsule is polished in order to destroy the epithelium present on it. When polishing is completed, an intraocular lens is inserted into the eye instead of the removed lens, and the incision is sealed without stitches. Ultrasonic phacoemulsification is the “gold standard” in modern surgical treatment of cataracts, since the technique is simple, widely available and rarely causes complications.
The best options for cataract surgery are ultrasound and femtolaser phacoemulsification. If possible, it is better to perform femtolaser phacoemulsification. But if there is no such possibility (for example, there are no funds for the operation, or there is no necessary equipment in the medical centres within reach), ultrasonic phacoemulsification can be safely performed.
Cataract Surgery Procedure
The patient is introduced to the stages of the surgery. They are told how important it is not to worry and to carry out the doctor’s commands ‒ to look straight, without blinking, to look down, to focus on a certain point.
1-2 hours prior the surgery drops are instilled to dilate the patient’s pupils. When the drops start working, the doctor invites the patient to the operating room. The patient should be dressed in a short-sleeved T-shirt for constant pressure control. A sterile outfit is also required. Prosthetics is performed on the operating table. The total time of the procedure rarely exceeds 30 minutes. Drops with anesthetic are instilled, in rare cases the anesthetic is injected.
Modern procedures are based on the principle of ultrasonic or laser phacoemulsification. The essence of the surgery is the grinding of the lens and its exhaustion from the chamber.
At first, through a micro incision (2 mm) a special fluid is introduced into the anterior chamber of the eye. It must protect the tissue from radiation, especially the cornea. Then the surgeon performs the procedure called capsulorhexis ‒ opening the lens chamber and partially removing it.
After that, a device with an ultrasound-emitting tip or a laser is inserted into the lens. The grinding process begins. The lens turns into a liquid emulsion. The patient does not feel any pain. They may see flashes of light, red laser lights, etc. The destroyed lens tissues are removed with an aspirator.
Then a tube in which a folded artificial lens is placed is inserted into the incision. The lens gets smoothed out on its own, the doctor can only slightly adjust the process. The patient will feel it as a slight pressure, stroking the eye. Suturing is not required. After the surgery the patient goes home right away.
Types of Intraocular Lenses
Selection of an intraocular lens is a rather complicated and time-consuming process, and most importantly the most important factor for a successful surgery, since the quality of the patient’s vision after the operation depends on the correct lens. Individual selection of the lens is carried out by a specialist with the help of specialized equipment (the methods are described in the section “Cataract Diagnosis”). The choice also depends on the patient’s desire to see well without glasses at near or far distances. Careful selection of an intraocular lens is so important because all the lenses are different, so you need to make the only right choice for your eye.
At present, the following types of lenses are used in ophthalmology:
- A monofocal intraocular lens ‒ the most commonly used type of artificial lenses. It provides the highest quality of vision at far distances, regardless of the degree of illumination in the area or in the room. At the same time, near vision (writing, reading, sewing) needs minor correction with the help of glasses.
- An accommodative monofocal intraocular lens ‒ can easily change its location in the eye, which contributes to focusing the image on the retina, regardless of whether the patient is looking at a near or far distance. The accommodation of such a lens is similar to the natural accommodation of a healthy lens. After the surgery the patient can easily do without glasses.
- A multifocal intraocular lens ‒ due to the manufacturing peculiarities, they have ultra-precise optical characteristics, imitating the work of a healthy eye lens, which allows the patient to see without glasses equally well at any distance after the operation.
- A toric intraocular lens ‒ due to its cylindrical shape, it is able to change the refractive power in certain areas, which is very important in correcting corneal astigmatism, which is often a complication with cataracts.
- An aspheric intraocular lens ‒ has all the characteristics of a healthy lens; in addition to high visual acuity, the implantation of this type of lenses provides high sharpness and contrast sensitivity of vision.
The best lens is an accommodative one. A multifocal lens is a little inferior to it. But these types of lenses are very expensive, so not everyone can purchase and have them implanted. In principle, in terms of price/ comfort, the best lens is aspheric ‒ it is fairly cheap and provides good vision in any lighting conditions. Besides, the need for additional use of glasses is not too burdensome, because the person, as a rule, has already got used to wearing them.
After the operation is completed, a sterile dressing is applied to the operated eye. A few hours after the surgery the operated eye has a sufficiently good vision, and within a week the visual functions come to normal for good.
If the patient did not have any complications during the operation and in the early postoperative period, he is discharged home the next day. It is necessary to avoid excessive eye strain, lifting weights and abrupt movements. The patient should also maintain eye hygiene, avoid sudden temperature drops and refrain from alcohol for at least 3-4 weeks after the surgery.
On returning home, the patient reverts to the usual way of life. Reading, writing, watching TV, etc. are allowed. Individually, the doctor prescribes eye drops to reduce the recovery period, and also informs the patient about the need for preventive examinations.
Complications of Cataract Surgery
According to the American Society of Cataract and Refractive Surgery, in the USA about 3 million cataract surgeries (IOL implantations) are performed annually (there are no data for Russia). The number of successful operations is more than 98%. The resulting complications are currently in most cases successfully cured by conservative or surgical means.
The most common complication is clouding of the posterior lens capsule or “secondary cataract.” It has been found out that the frequency of its occurrence depends on the material the lens is made from. So, for IOL from polyacryl it makes up to 10%, while for silicone it is already about 40%, and for those made from polymethyl methacrylate (PMMA) 56%. The true causes of this complication and effective prevention methods have not been established yet.
It is believed that this complication may be due to the fact that the lens epithelium cells remaining after the removal migrate into the space between the lens and the posterior capsule and, as a result, form deposits that deteriorate the image quality. The second possible cause is fibrosis of the lens capsule. The treatment is carried out by using a YAG laser, with the help of which a hole is formed in the central zone of the opacified posterior lens capsule.
In the early postoperative period intraocular pressure may increase. The reason for this may be incomplete wash-out of viscoelastic (a special gel-like preparation injected into the anterior chamber of the eye to protect its structures from damage) and its penetration into the drainage system of the eye, as well as the development of the pupillary block when the IOL shifts to the iris. In most cases, it is enough to use antiglaucoma drops for several days.
If there is a risk of developing cataracts, it is important to use comprehensive means of prevention. These include the use of eye drops (Quinaks, Taufon, Vicetin, etc.), after prior consultation with the doctor.
The remaining preventive measures are as follows:
- Wearing sunglasses that can block the impact of ultraviolet radiation on the lens of the eye.
- Mandatory visits to an ophthalmologist at least 2 times a year.
- Regular measurements of blood sugar levels and timely treatment of diabetes.
- Use of foods rich in antioxidants, as well as fruits and vegetables.
- Frequent hand washing, which to some extent helps to protect the organs of sight from infection of various genesis, which reduces the risk of developing cataracts.
- Giving up bad habits.
- Compliance with safety rules when working with potentially hazardous substances in hot workshops, chemical laboratories, etc.
However, doctors note that there are no universal methods for preventing the disease. Therefore, persons over 65 should definitely visit an ophthalmologist regularly and, if lens opacities are detected, treat this pathology promptly. As for people who have not crossed this age threshold, they need to visit a doctor at least once in 4 years and have a balanced diet.
If you have found symptoms of cataracts in yourself or your relatives, it would be right to listen to the following tips:
- Do not drive your eyes to cataract blindness.
- Book in a consultation with an ophthalmologist to confirm the diagnosis.
- Do not self-medicate.
- For the highest possible results, it is necessary to accurately choose the artificial lens optimal for the patient.
- Advertising promises to cure cataracts with drops and pills, but it is a way of deception by unscrupulous entrepreneurs.
- The successful result of the operation depends 90% on the professionalism of the cataract surgeon.
- You can reasonably save on treatment by choosing clinics that hold special promotions for their patients.
The prices for cataract operations different depending on type of surgery and clinic but in Europe the average costs 30-60 per cent lower than oversea.
Applying via GMG you have possibility to choose among the best clinics in Germany. Please ask for details and qualified ophthalmologists explain you the whole process and give you affordable quotation.
|Cataract surgery, per eye (including surgery, IOLS and postoperative care)||1750€||3478$ / 3150€||2406£ / 2675€|
*All the prices are based on a few estimations from different sites and could not be an offer. Please enquire to clinics for precise pricing
The air tickets prices from US to Germany starts as low as 490 EURO when buying in advance, and the prices for a flight from London to Germany starts from 48 EURO.
A well-known Clinic of refractory and ophthalmic surgery (cataract treatment) in Duisburg offers an accurate diagnosis and quality treatment of any type of disease of the entire anterior segment of the eye. The institution has an international certification DIN (approx. Deutsches Institut für Normung – German Institute for Standardization): ISO, which indicates the high quality and safety of services that are provided here. It is worth saying, that the clinic serves more than 12,000 patients a year, who come here even from abroad, having heard about the high quality surgery and, above all, about the masterly treatment of cataract.
Dr. Marc Thomalla is a medical director of the clinic. He began his career in the early 90s as a specialist in ophthalmology and has held since that time more than 28,000 surgical procedures. He is a member of various international and national associations (for example, ASCRS, BVA, ESCRS, KRC, VRI, AAO, DGII), the author of scientific papers and textbooks, among other things, Dr. Thomalla doesn’t stop studies relating to laser therapy, thanks to which doctors began using femtosecond laser for the treatment of cataracts.
In this medical center all kinds of treatment are introduced strictly in quality management.
The field of expertise:
- Surgery to remove cataracts and glaucoma;
- Conservative cataract tretment
- Diseases of the retina and retinal detachment;
- Injuries and diseases of the cornea;
- Strabismus (children and adults);
- Ametropia (farsightedness, nearsightedness, astigmatism);
- Cosmetic problems century.
In addition to the standard range of services in the field of ophthalmology, we also offer:
- Selection of contact lenses;
- The expert’s conclusion (eg. for a driving license);
- Laser therapy after recurring cataract, glaucoma, retinal diseases, (solid-state laser YAG, SLT – Selective trabekuloplasty, ALA – automated lamellar keroplastic);
- Optical biometry;
- Orthoptic office;
- Surveying for suitability to work before the monitor according to the rules of safety and health branch of the Association of insurance companies. (37 F);
- Certificate about the state of applicants for a driver’s license in all categories;
- Early diagnosis of glaucoma;
- Methods of laser vision correction “LASIK”, “PRK”, “Epi – Lasik”, “LASEK”;
- The method of wave-front
- Cataract treatment
If you have questions or you would like to apply for treatment, please contact the clinic. We would be glad to consult you on modern methods of eye diseases treatment. Our website features information on a the best German ophthalmic centers, such as Landshut eye center, Sehkraft in Cologn, Augenlaser Team in Munich and many others. All of them are real specialists in cataract treatment.