The common case is primary or chronic open-angle glaucoma, with 2/3 of cases. This occurs when there is an open drainage area where the liquid exits from the eye, but it is not functioning well and the eyeball tension increases. Sometimes drainage hole become narrow and close gradually, it is the chronic type of closure. If the drainage angle is suddenly closed it is the acute type of closure.
Glaucoma with acute closure of the eye`s angle causes severe sudden eyeball pressure rise and is typically painful with the development of redness. Vision is blurred, you can see halos around bright spots of light.
This type of disease may cause a strong sudden pressure increase, as a rule, with the development of painful redness. The vision is blurred, and you can see the halo. Congenital glaucoma can be detected by parents. The children of small age have easily expandable sclera of the eye, so that the eye tension increases with an increase of intraocular pressure. Gaps appear in the corneal endothelium, what leads to edema or swelling of the cornea, which produces a misty, frosted glass view. As corneal stretching, ruptures allow more liquid to fall into corneal stroma and epithelium, which leads to a sharp increase in edema and haze, increased lacrimation and photophobia. The child may become irritable and hide his head in the pillow to avoid the pain caused by bright light.
Glaucoma with narrow eye`s angle - is the anatomical form of the eye, which sometimes leads to high eye tension that can cause glaucoma. When the aqueous solution is discharged with approximately the same rate at which is made, it supports the normal eyeball pressure. If this water solution may not run as fast as it is produced, the pressure in the eye increases. This can occur if the opening is too narrow.
The harmed optic eye´s nerve without increased eye´s pressure is known as "low pressure glaucoma".
The classification of glaucoma is as follows:
- Congenital glaucoma. Develops in an infant in the prenatal period or during childbirth. A common cause is a transferred illness of a pregnant woman, especially of an infectious nature (rubella, poliomyelitis, syphilis, parotitis (mumps), typhoid fever, etc.), hyperthyroidism (thyrotoxicosis), hypovitaminosis A, poisoning, drinking alcohol, or trauma.
- Juvenile (youth) glaucoma. It is observed mainly in children in 3 years old and up to 35 years of age.
- Primary glaucoma. The development of the disease occurs mainly due to the eye development pathology, or the characteristics eye's structure, developmental abnormalities, as well as age-related changes in the eye.
- Secondary glaucoma. The development of the disease occurs against the background of another eye illness or injury previously treated.
- Open-angle glaucoma. The most common type - occurs in 90% of all cases. A characteristic feature of the open-angle glaucoma is its asymptomatic course - the patient usually notices in many years that one of his eyes vision is distorted, with rainbow colors, or is limited, but this symptom alone already indicates partial atrophy of the optic nerve. The cause of open-angle glaucoma usually lies in the high intraocular pressure (ocular hypertension), with open access to the natural drainage system, and its malfinction.
- Closed-angle glaucoma. A characteristic feature of the closed-angle glaucoma is the overlapping of the eye drainage system, which disrupts the normal outflow of the eye fluid. Due to this pathology, the patient feels (in addition to the vision defects (rainbow colors, halos around the light source, etc.) or limitations of visual function) a number of additional signs of the disease – pain in the eye and the corresponding half of the head, redness of the eye, corneal edema, dilation of the pupil and the lack of its reaction when exposed to light.
- Mixed glaucoma. The development occurs due the simultaneous impact of several adverse factors on the organism.
- Glaucoma with normal intraocular pressure. It is characterized by vision deterioration, partial atrophy of the optic nerve and other primary glaucoma symptoms, while the level of intraocular pressure remains normal. In many cases the development of the disease occurs against the background of vegetative-vascular dystonia (VVD) of hypotonic type.
By the development (Stages of glaucoma)
The stage is defined by the visual field and optic nerve disk state.
- Stage 1 (the initial stage of glaucoma). Intraocular pressure doesn't exceed 26 mm Hg. The visual field of view borders are normal, sometimes defects in the form of rainbow shades are observed. Visual function deterioration doesn't occur within 6 months.
- Stage 2 (stage of glaucoma development). Intraocular pressure is 27-32 mm Hg. The field of view narrowing, as well as visual changes of the optic nerve are observed (determined by the ophthalmologist).
- Stage 3 (advanced stage of glaucoma). The intraocular pressure is 33 mm Hg and higher. There is an extensive narrowing of the visual field.
- Stage 4 (terminal glaucoma stage). Accompanied by partial vision, representing a small visible spot in the temporal part, or a complete lack of visual function.
By the course of development
- Pre-glaucoma. It manifests itself occasionally, usually due to strong emotional experiences or prolonged stay in the dark, and is accompanied mainly by rainbow circles when looking at the light. Occurs most often in persons with a narrow or closed angle of the anterior eye.
- Acute glaucoma attack. Develops due to the negative external factors impact on the organism: severe stress, prolonged stay in the dark, overwork, uncontrolled use of drugs, fluid excess in the body, prolonged work with head inclined forward, sedentary work. Accompanied by sharp pains in the eye and head, rainbow circles when looking at the light, blurred vision, eye redness, corneal opacity, the lack of the pupil reaction to the light, a sharp decrease in visual acuity, the eye becomes very dense to the touch. High intraocular pressure (up to 80 mm Hg), compression of nerve fibers located in the iris root and the ciliary body, as well as edema of the cornea, contribute to these symptoms. Additional symptoms may include dizziness, nausea, vomiting, pain in the chest (left side) and abdomen.
- Chronic glaucoma. It is characterized by a gradual progressive intraocular pressure rise (IOP), blockade of the anterior eye angle and periodic subacute attacks. Over time leads to atrophy of the optic nerve and complete loss of vision (blindness).
The development of dangerous pathology requires a combination of factors. For a long time it was believed that the causes of the disease were reduced to increased intraocular pressure. The medics then revealed that this factor increases the optic nerve fracture risk, but is not fundamental for the glaucoma development. The progression of the disease requires a sequence of causes that trigger the mechanism of the eye malfunction.
Adult people over 40 are the most vulnerable to the disease. After identifying the pathology, it is necessary to start treatment immediately - pathological changes are irreversible. Causes of glaucoma in adults:
- Imbalance between outflow and inflow of moisture in the eye cavity, accompanied by high intraocular pressure;
- elderly, old age;
- hereditary background;
- presence of myopia;
- inflammatory eye diseases, for example, uveitis;
- dilateing pupils medications;
- smoking, alcohol addiction;
- the following diseases: diabetes, hypotension, atherosclerosis, thyroid gland disorders;
- eye swelling;
- burns, eye injuries.
Some babies have congenital abnormalities that occur due to hereditary factors or congenital disorders in the structures of the eye. Due to the obstruction of the liquid outflow in a child, the intraocular pressure rises, the optic nerve receives less nutrition. Causes of primary glaucoma in children:
- Defects in the eye development;
- maternal smoking during pregnancy, previous infections;
- mother's diseases that affected the pathology development in the fetus (vitamin A deficiency, parotitis, syphilis);
- hereditary background.
The whole circulatory system suffers from the lack of insulin produced by the pancreas, the eye retina is also affected. Glaucoma in diabetes has some peculiarities of development. In diabetes, constant changes in the level of sugar occur, which is why the organism forms too many new blood vessels. They cause huge damage to the eyes, growing into the iris and disturbing the outflow of intraocular fluid. As a result of pathological changes, the entire visual system suffers, and the risk of blindness increases.
If you're suffering from glaucoma – causes, symptoms, treatment and prevention of this disease might be interesting for you. At the initial stage the disease is asymptomic, and this poses a danger. The patient doesn't feel anything strange, and the disease can be found on a standard medical examination. In case of the sharp-angled glaucoma, an increase in the amount of liquid can be observed, but the eye looks normal. In some cases, people may complain about reduced vision in the dark, the appearance of rainbow circles, headache. Sometimes they note that one eye can see, and the other is blind.
The symptoms of the closed-angle form of the disease are more pronounced. The ophthalmic examination detects the closed (narrow) angle of the anterior eye. Other characteristic features of closed-angle glaucoma:
- Visual discomfort;
- pain in the eye;
- rainbow circles in the light;
- redness of the eye;
- vomiting, nausea;
- blurred vision;
- dilated pupil, non-responsive to the light;
- narrowing of the field of view;
- short-term vision loss.
Unfortunately, many people diagnosed with this disease miss specific symptoms (if present). Their presence does not necessarily mean intraocular pressure, but is the reason to see an ophthalmologist. The first signs of glaucoma:
- Pain in the eyes (pronounced, weak);
- blurred vision in poor light;
- a feeling of heaviness in the eyes;
- weakening of vision;
- deterioration of peripheral vision.
The development of glaucoma depends largely on the negative factors (causes) that lead to this pathological process. However, modern ophthalmologists have not yet approved a single, clear opinion on the causes of this disease. The only thing the majority of doctors are sure about is the occurring of the disease due to simultaneous or gradual development of several negative factors in the body, and namely, in the eye.
If you summarize them, you can deduce a single picture - glaucoma develops due to malnutrition of any part of the eye, the function of which is performed by aqueous humour (intraocular fluid).
Intraocular fluid fills the entire cavity of the eye, its anterior and posterior chambers. In addition to feeding all parts of the eyeball, it also performs the function of controlling the intraocular pressure and maintaining the tonus of the whole eye. In case of a violation in its inflow or outflow, a number of pathological processes appear in the eye - an increase in intraocular pressure, obstacles in the blood supply to the eye, the death of retinal cells, etc.
All these factors usually lead to the optic nerve atrophy and in consequence, to blindness.
The onset of glaucoma is marked with the limitation of the visual field - visible objects become fuzzy, then darken. Over the years, the clearly visible part decreases, the restriction increases, the patient sees the surrounding world as though through a dark tunnel. Further development of the disease continues to limit the visual function even more.
Why does intraocular pressure increase?
The anterior and posterior chambers of the eye are filled with aqueous humour, which is synthesized by the ciliary body. This fluid contains glucose, ascorbic acid, B vitamins, proteins, various minerals, and hyaluronic acid. Its main function is to provide the lens and cornea with nutrition, parts of the eyes deprived of other sources of nutrition (with the exception of the cornea surface layers, which receive the necessary metabolites from the lacrimal fluid).
Aqueous humour is formed in the posterior chamber, from where it moves through the pupil to the anterior chamber. From the eye, it flows through the angle of the anterior chamber, which is located between the root of the iris and the peripheral part of the cornea. Together with intraocular fluid, the lactic acid, carbon dioxide and other metabolic products are also excreted from the eye chambers.
Normally, there is a certain balance between the formation and outflow of aqueous humour. Intraocular pressure may increase either due to excessive production, or due to disruption of the fluid outflow circulating in the chambers of the eye. The first occurs in case hypertrophy of the ciliary body, which develops mainly in individuals with high degrees of myopia.
Violation of the outflow of intraocular fluid is a consequence of closing the angle of the anterior chamber or trabecules blockage through which the filtration of moisture occurs. These phenomena can be caused by a number of provoking factors.
The main problem in the diagnosis of open-angle glaucoma, is the lack of typical symptoms in the early stages. Many people who have this disease are unaware of it. Therefore, it is very important, especially in old age, to undergo regular examination by an ophthalmologist. There are several methods of glaucoma diagnosis:
- Eye pressure is measured by tonometry. Eye pressure testing is an important part of glaucoma diagnosis. High intraocular pressure is often the first sign of illness. In some cases analgetic drops are used before the procedure. The cornea resistance to pressure is measured with the help of a special device – a tonometer. Normal intraocular pressure is 10 to 21 mm Hg. However, in people with normal tension glaucoma, with intraocular pressure less than 21 mm Hg, there may be damage to the optic nerve and loss of visual fields.
- Ophthalmoscopy (Examination of the optic disc to detect signs of its damage) is performed with the use of ophthalmoscope - a tool that allows you to examine the internal structure of the eye in the zoom. The pupil is expanded with the help of special drops. Glaucoma damages the optic nerve, causing the death of its constituent fibers. As a result, its appearance changes, it resembles a cup. If its size increases, dark spots appear in the field of view.
- Gonioscopy (examination of the anterior chamber angle) allows you to get a clear idea of the eye interior chamber angle state to determine the type of glaucoma. It is difficult to do this in the course of ordinary examination. Using a mirror lens makes it possible to inspect the angle of the anterior chamber and establish the presence of an open-angle (if the angle of the anterior chamber does not function effectively) or closed-angle (if the angle of the anterior chamber is at least partially closed) of glaucoma or a dangerous narrowing of the anterior chamber (when the iris is so close to the drainage system of the eye that can block it).
- Pachymetry is the measurement of corneal thickness. This indicator may affect the accuracy of IOP measurement. If the cornea is very thick, the intraocular pressure will actually be lower than the tonometry data. And, on the contrary, when the cornea is very thin, the true intraocular pressure is higher than the measurement shows.
- Perimetry reveals "dark" spots in the field of view. The test results will show their presence and localization. Some of them the patient may not even notice. The test is performed using a cup-shaped instrument called a perimeter. Only one eye can be checked at a time, so the second eye is covered with a bandage during the examination. The patient should look straight at the target. The computer gives a signal and the glowing dots begin flashing in random order inside of the device. The patient should press the button when they see them. Not every sound signal is accompanied by the appearance of a flash. Perimetry is usually carried out every 6-12 months to monitor changes.
Medical treatment of glaucoma is carried out in three directions:
- Reduction of intraocular pressure (ophthalmic-hypotensive therapy);
- improvement of the retina and intraocular part of the optic nerve blood supply;
- normalization of metabolic processes (metabolism) in the tissues of the eye in order to influence the dystrophic processes typical for glaucoma.
The crucial moment in the glaucoma treatment -normalization of the intraocular pressure level, while the methods aimed at improving blood circulation and the impact on the metabolic processes in the eye are auxiliary. In addition, the correct mode of work and life of the patient is required.
Variants of medication impact on intraocular pressure:
- IOP decreases after the first instillation of the drug. Repeated applications help to maintain this effect.
- The effect of the drug is not immediate - poorly expressed initially, and in the following days is more pronounced under the condition of regular drug instillation.
- Resistance to the drug doesn't affect the IOP.
In addition, sometimes drugs have a paradoxical effect - the pressure doesn't reduce, but increase instead after the instillation of the drops. Therefore, a diagnostic test is prescribed for each anti-glaucoma drug.
When prescribing the instillation schedule of anti-glaucoma drops, the patient must visit the doctor regularly for at least 2-3 weeks. Subsequently, the control of glaucoma treatment effectiveness is carried out at least once every 3 months.
Regular replacement of drugs after 1-2 years with appropriate re-control is highly recommended to prevent the development of drug resistance.
Medicines used in the treatment of glaucoma are divided into two large groups: drugs that improve the outflow of intraocular fluid from the eye, and drugs that oppress the production of aqueous humour.
The main task of anti-glaucoma drops is the IOP decrease. On the influence mechanism and hypotensive action anti-glaucoma drops are divided into 3 groups:
- Drops reducing intraocular pressure by improving blood flow and outflow of aqueous humour from the eyeball. This group of drugs is also called myotics.
- Drugs that reduce IOP by reducing the aqueous humor production. Normally, cilia of the ciliary body are responsible for this function.
- Combined action drug - drugs that reduce the production of aqueous humour and improve the outflow of intraocular fluid at the same time. The effect of these drugs lasts at least 12 hours (up to 24 hours).
Laser treatment of glaucoma is used in case of medical therapy low effectiveness and is intended to form additional ways of outflow of intraocular fluid.
The most popular laser treatment methods are:
- trabeculopuncture (outflow activation);
- transcleral cyclophotocoagulation (contact and non-contact).
The operation is performed under local anesthesia. A special lens is installed in front of the patient's eye, through which a laser beam is transmitted. This beam makes small punctures in the trabecular reticulum through which the fluid outflow occurs, and the intraocular pressure decreases.
An alternative method is the so-called cyclodiode laser treatment. It includes the destruction of certain eye areas in which the liquid is formed. As a result, less fluid is formed in the eye and the intraocular pressure is reduced.
Laser treatment is fast and painless. It can be carried out at any age.
Laser iridectomy is a relatively inexpensive, fast and fairly effective method of treating glaucoma. The powerful energy of the laser beam is directed precisely to the selected place in the iris and coagulates it, creating the necessary through hole.
Indications for Laser iridectomy
- Chronic course of closed-angle glaucoma, especially accompanied with acute attacks.
- Acute attack of closed-angle glaucoma as a method of emergency care.
- In case of mixed glaucoma.
- Narrow iridocorneal angle.
- On the second eye for prevention purposes, since in 50% of cases the second eye with closed-angle glaucoma is also prone to acute attacks, according to statistics.
- After other glaucoma surgery.
- As a preliminary step for some other operations.
Contraindications for laser iridectomy
- Corneal opacity violation.
- Severe corneal edema.
- Flat anterior chamber.
- Paralytic mydriasis (pupil dilation due to a innervation violation).
- Neovascular glaucoma.
- Patients not able to hold the head in a fixed position for a long time.
There are laser iridotomy ("burning" the hole in the iris) and laser iridectomy (a part of the iris removal).
Laser open-angle and closed-angle glaucoma treatment can be carried out using the following methods:
- Argon laser trabeculoplasty (ALT). Such an operation brings only temporary relief and is aimed at encouraging an increase in the grid windows. This is a traditional operation with the use of thermal argon laser;
- selective trabeculoplasty (SLT), using a cold laser. A more modern method, which reduces the trauma during the operation. This allows to use this method 3-4 times, whereas traditional trabeculoplasty can be done only once;
- peripheral iridectomy is performed using a YAG laser, which makes it possible to make a small through hole in the iris of the eye. In this case, an equalization of pressure inside the eye is observed, which largely prevents the risk of an acute attack with a closed-angle form of the disease, prevents the appearance of iris adhesions with the trabecular network;
- peripheral iridoplasty is an application of light laser coagulants to the iris periphery, as a result of which the angle of the anterior chamber is expanded due to wrinkling and retraction of the iris stroma;
- pupilloplasty is carried out with the application of coagulants with the help of laser to a certain sector of the iris, in case of laser iridectomy impossibility. In this case, the pupil is tightened and the angle of the anterior chamber is released.
Laser iridectomy is performed on an outpatient basis. The patient sits in a special chair, ensuring the immobility of the head. Before the procedure, the eye drops are instilled to narrow the pupil (pilocarpine), then — anesthetic solution. A special gonioliosis is applied to the eye, which allows a good view of the angle of the anterior chamber and focusing the effect of the laser in the desired area.
After the onset of anesthesia, the doctor focuses the laser beam on the selected area of the pigment shell. Usually areas 11 and 1 hour are chosen, with better upper lid coverage. It is recommended to work on several different areas.
The whole procedure lasts about 20 minutes on average.
Within an hour after laser iridectomy, blurred vision is possible, then this sensation disappears.
In an hour after the operation the intraocular pressure is measured, as its increase is possible. If this happens, drops are used to reduce it.
Several days after the procedure it's also necessary to instillate anti-inflammatory drops.
Advantages of Laser iridectomy
- Possibility of outpatient, without hospitalization.
- No general anesthesia is required.
- Minimum complications.
- Minimum rehabilitation pediod.
- Low operation cost.
Laser Treatment Imperfections
- The hole in the iris overgrow over time, and requires re-operation. Repeated procedures are more often required for patients with brown iris than with grey and blue ones.
- During the first hour after the procedure reactive hypertension is possible.
- There is a risk of local corneal and lens capsules burn with laser beams.
- A fusion in the area of iridotomy is also possible.
Selective laser trabeculoplasty is the most effective and safe modern method of laser glaucoma treatment. The operation allows to normalize the pressure inside the eye, including in patients insensitive to medical treatment and in case of its contraindication. This procedure prevents severe glaucoma complications, helps to avoid surgery, makes it possible to return the patient to a normal life.
Trabeculoplasty surgery restores fluid outflow in open-angle glaucoma. Laser surgery is not capable to return normal eyesight, but it prevents further progression of the disease quite often.
Varieties of this operation:
- Selective laser trabeculoplasty. It is characterized by selective effect solely on cells that contain pigment. Selective laser trabeculoplasty has less destructive effect on the blood-ocular barrier and the trabecular apparatus of the eye. It's considered the most gentle procedure which can be carried out repeatedly.
- Argon laser trabeculoplasty. It has a higher power of laser exposure. Post-coagulation burn, and accordingly, the process of scarring in this area is more pronounced. Not recommended for repetition.
- The ineffectiveness or intolerance of conservative therapy;
- primary open-angle glaucoma;
- aphakic, pseudo-exfoliative, postuveal glaucoma;
- moderate, pronounced pigmentation trabekul angle of the anterior chamber of the eye;
- in cases of patients unable to conduct drug treatment regularly for whatever reason.
It is not advisable to use this procedure for the following types of glaucoma:
- Operated advanced glaucoma;
- inflammatory genesis;
- in cases of closed-angle glaucoma this method is not used at all.
It's also prohibited to use this operation on the background of diabetic retinopathy, due to the presence of goniosynechia, neovascularization and pronounced proliferative activity.
As a rule, such procedure is carried out on an outpatient basis. For its implementation a high-energy laser beam is used, the doctor applies about 50 tiny point burns to the surface of the trabecular meshwork. Trabecular meshwork is a part of the drainage system belonging to the anterior chamber of the eye, and the increase of its cellular power improves the outflow of the liquid.
Before the procedure, which is almost painless, the doctor carries out the local drip anesthesia, which allows to install a special reflective surface lens to the eye (goniolens). The patient settles in a comfortable pose before a lamp, the ophthalmologist places a lens in one eye, with the other eye fixed on any object. The treatment takes less than half an hour, during which the patient can see green and red flashes of a laser.
After selective laser trabeculoplasty, the following complications might occur:
- Infectious complications (conjunctivitis, keratitis) occur in 3-5% of cases;
- allergic manifestations (swelling, itching, burning, redness of the ocular mucosa);
- temporary increase in IOP (is possible during the 1st week after surgery);
- lack of the procedure effectiveness (observed in about 12% of patients), which requires another surgery in the future.
Successfully conducted laser trabeculoplasty is quite effective in normalization of intraocular pressure, prevents the glaucoma progression, as well as the development of complications. However, a few years after the procedure, almost 50% of patients observed an increase in intraocular pressure to a dangerous level. In such cases surgical intervention is necessary.
Laser gonioplasty is the procedure for coagulation ("burning") of the iris in its root zone. Through laser exposure, immediate induration, and reducing the tissue volume is achieved, which helps to release the angle of the anterior chamber. Laser gonioplasty is especially affective in narrow-angle glaucoma, in the case of pre-attack disease.
As a rule, this operation is performed as an auxiliary one, since the result obtained is usually temporary. But the access to the corner of the anterior chamber, simplifies the second stage of laser glaucoma treatment - trabeculoplasty.
Laser gonioplasty is performed using a conventional type of "thermal" lasers.
The intervention zone is the root area of the iris along its entire circumference (360 degrees). Manipulation is carried out with a distance of two spot diameters between the coagulums, avoiding visible radial vessels.
Laser gononoplasty as an independent intervention is used extremely rarely, due to the temporary effect of its result. As a rule, this operation becomes the first step to laser iridectomy or laser trabeculoplasty. After opening access to the angle of the anterior chamber, laser goniopuncture - the second step of the treatment, is greatly simplified. Coagulation of the iris during laser gonioplasty promotes rapid hyphema resorption of anterior chamber of the eye.
Indications for Laser gonioplasty
Laser gonioplasty procedure is prescribed in the following cases:
- With narrow-angle and close-angle glaucoma, with the aim of expanding the profile of the angle in the anterior chamber, by retraction of the iris root from the trabecular zone.
- In the course of preparation for the laser trabeculoplasty in order to expand the angle of the anterior chamber of the eye to improve the visualization of the trabecular area.
- In the case of "flat" iris syndrome.
Benefits of the procedure
The main advantages of laser gonioplasty are as follows:
- Painless method – the procedure is performed quickly and under local anesthesia;
- Minimally invasive – when intervening, the chamber of the eye is not opened;
- Low risk of possible complications;
- Quick rehabilitation after surgery;
- Simplicity of intervention-the procedure is carried out in one day, if necessary, simultaneously in both eyes during one procedure;
- The low cost of the method, which makes it affordable to almost all patients.
Complications of Laser Gonioplasty
Like any surgery, laser gonioplasty can cause some complications. The most frequent and undesirable consequences of the procedure are: iritis, increased IOP, damage to the corneal endothelium, persistent mydriasis (pupil dilation).
The laser gonioplasty procedure is not performed for persons under the age of 18, as laser intervention during the period of active organism growth can cause an unpredictable result.
Laser surgeries are prohibited during pregnancy and breastfeeding, in case of total one-eye blindness, as well as in case of viral eye infection or general systemic and autoimmune diseases.
Cyclophotocoagulation (synonymous with cyclotherapy or cyclo-dissection) is a popular method that allows to treat glaucoma at the terminal stage. It can also be used in case of permanent pain syndrome. Cyclophotocoagulation is the last measure the ophthalmologist may offer, when other methods are ineffective, when it is not possible to use certain groups of drugs, and when preserving the eyeball is at stake.
The main objective of this procedure is to reduce the amount of fluid in the eye cavity. It's achieved by the operative destruction of a ciliary body part producing moisture. In the relatively recent past, when ophthalmologic clinics didn't have their own lasers, the ciliary body of the eye was attempted to be affected by an electrotherapy method or through cryotherapy sessions.
However, these attempts were found to be ineffective due to weak control over the area of the artificially destroyed tissue. As a result of the destructive impact of these procedures, the eye lost the amount of moisture necessary for normal functioning.
Cyclophotocoagulation is an incomparably more accurate and minimally invasive solution that causes fewer complications, destruction and infection of the operated tissues.
For this reason, this procedure is offered to patients with high IOP level. Patients with abnormal IOP often experience eye pain, to the extent that the optic nerve may be damaged and vision lost.
Today, ophthalmologists widely use a number of methods to establish the production of normal volume of the eye fluid. Among the methods of cyclodestruction are the following:
- Cyclocriotherapy, that is freezing with liquid nitrogen, is used relatively rarely;
- noncontact transscleral cyclophotocoagulation, which uses a neodymium YAG laser;
- contact transscleral cyclophotocoagulation using a contact laser semiconductor G-probe;
- endoscopic cyclophotocagulation.
A kind of cyclodestruction - endoscopic cyclophotocoagulation - is often more preferable then the other methods. The method can be performed independently or be combined with the removal of cataracts. After the probe equipped with a microlaser and a light source, is inserted in the eye, the ophthalmologist observes the state of the ciliary body, moving it around the iris. After laser exposure, the liquid will be produced only by a part of the surviving cells. Diode or neodymium types of lasers can be used for eye surgery.
The indications for cyclophotocoagulation are the terminal stages of neovascular, traumatic, open-angle, primary, and secondary glaucoma, injuries after unsuccessful keratoplasty, a blind aching eye.
Contraindications - pronounced uveitis, malignant neoplasms of the distal segment of the eye, good vision.
Complications of cyclodestruction
Physicians are most concerned about chronic hypotension, occurring in approximately every 10 patients, as well as ophthalmia, which occurs less frequently. There may be subsiding pain after surgery for several days. Usually they are eliminated by the analgesic drugs.
In glaucoma, patients need systematic and long-term treatment, always under the supervision of a physician. As a rule, treatment begins with the medication: eye drops are instilled, reducing intraocular pressure; pills, improving nutrition of the optic nerve and retina are prescribed.
In some rare cases, with such treatment, the intraocular pressure normalizes and the state of the optic nerve does not deteriorate, but such cases are rather rare. In this situation, medical treatment is enough, however, the drugs will have to be applied for life.
Therefore, experts have developed some game-changing new methods of glaucoma treatment: effective, safe and less traumatic. These include laser treatment and surgery.
In the first case, the laser beam, penetrates into the eye freely and affects the drainage system improving the outflow of intraocular fluid. Laser treatment is painless, short on time, and is carried out on an outpatient basis. Its significant advantage is that the eyeball is not exposed to surgery.
Unfortunately, the laser treatment may not help some of the patients suffering from glaucoma. Such treatment can be effective only in the initial stages of the disease, when the intraocular pressure is only slightly increased.
Indications for surgery
Indications for surgical treatment of the disease don't depend on the type, stage or cause of its occurrence. The decision to perform the operation is made by an ophthalmologist according to the dynamic control data. At high rates eye tissues dying, it's risky to rely on drug treatment due to its being pretty time consuming. The following factors also make surgical intervention necessary:
- Low efficiency of conservative and other methods of treatment against the background of constantly increased eye pressure;
- optic nerve degradation;
- sharp deterioration of visual acuity;
- contraindications and side effects when taking medicines;
- the negative effect of the hypotensive drugs use.
The main advantage of the surgical method is the possibility to completely eliminate the causes of an increase in IOP. The operation can be performed without dissection, which reduces the risk of infection. Operations don't take much time and are carried out on an outpatient basis.
However, surgery has its drawbacks — the possibility of complications:
- Conjunctiva is gradually thinning at the site of intervention.
- The intermittent hypotensive effect decreases visual acuity over time.
- Scar tissue formation.
In rare cases, the operation may damage the iris or capsule lens vessels.
Types of glaucoma surgery
Options for surgery are divided into non-penetrating and penetrating methods. The latter imply the eyeball dissection to create new ways for the outflow of moisture by artificial means. Non-penetrating method does not require deep opening, affecting the existing ducts.
The type of surgery is chosen taking into consideration the state of the soft eyeball tissues. For example, the secretion of the intraocular fluid is regulated by the ciliary body. When the moisture is increased, the surgery will be directed to its partial destruction. The procedure is based on laser therapy.
If the large lens size prevents the outflow of intraocular fluid, the latter has to be removed. An artificial lens takes its place. Thus, doctors provide protection of optic nerve fibers and maintain visual acuity.
A safe method of open-angle glaucoma surgical treatment is non-penetrating deep sclerectomy. This procedure allows to establish a balance of secretion and excretion of liquid due to intensive moisture exchange with external environment. Since the corneal membrane has a natural water permeability, to stabilize the intraocular pressure, it's only necessary to thin the membrane artificially. This method allows to remove the eye fluid with the help of congenital ducts.
The effect of non-invasive sclerectomy is enhanced in combination with the collagen drains installation or with the use of laser therapy (argon, excimer laser, YAG). Types of drainage structures:
- Shunts. Form a passive outflow of fluid under the conjunctiva or in the area above the vascular membrane.
- Valves. Creates adjustable fluid circulation depending on the pressure inside the eye.
- Implants. Don't allow the upper and lower part of the scleral shell to merge.
The drainage system helps to avoid the connective tissue formation. The reduction of the effect after surgery creates several advantages of this procedure before other anti-glaucoma operations:
- The rehabilitation period is reduced to 2 days;
- the absence of visual limitations allows you to start full-time work in a week;
- bed rest is not required;
- drug support is not prescribed.
The non-invasive method of surgery reduces the consequences of complications to a minimum. The operation is carried out even in the early stages of glaucoma, when the structure of the optic nerve is not altered and the natural drainage system circulates.
In contrast to non-penetrating deep sclerectomy may offer sinus trabeculectomy with basal iridectomy. The basis is the penetrating method with the implant drainage system installation. The method is less popular, since it is used to deal with a complex clinical situation. During the penetrating treatment a small area of sine and trabecula drainage system is removed. The liquid circulates inside the eye normally, the pressure returns to normal. This method provides efficiency in 60-80% of cases. The operation lasts 20 minutes and requires strict compliance with the ophthalmologist recommendations during the postoperative period. Complications may arise in the form of scar tissue formation. Scars may be removed with subsequent cosmetic surgery.
Although glaucoma is a serious disease which in the worst case, if left untreated, can lead to blindness, a glaucomatous patient can lead a normal life.
As long as there are no severe visual field defects that prevent from driving, the life of these patients is almost the same as that of a person without glaucoma. However, it must be emphasized once again that glaucomatous patients should adhere to the prescribed treatment regimen and regularly have consultations with their ophthalmologist.
Below you will find answers to some questions that patients with glaucoma often have.
Lifestyle and Nutrition
A patient with glaucoma, like any other person, may, of course, enjoy life and food, but you should always keep in mind moderation.
During the first hour after ingestion, coffee and tea can cause a moderate increase in intraocular pressure, but this effect is insignificant, so glaucomatous patients do not need to give up drinking these beverages. All glaucomatous patients should not restrict fluid intake, but its use should be evenly distributed throughout the day.
If a glaucomatous patient drinks a large amount of fluid within a very short period of time, let us say, one litre within a few minutes, intraocular pressure will temporarily increase. Therefore, it is recommended to use a sufficient amount of liquid, but it should be distributed evenly throughout the day.
A small amount of alcohol, especially wine, is well tolerated and also has a protective effect on the heart and blood circulation. Patients with glaucoma may consume a small amount of alcohol even every day, without worrying about the consequences for their eyes.
In the case of an acute angle-closure glaucoma attack, a large amount of strong alcoholic drinks can lower intraocular pressure (IOP) for several hours. Of course, drinking alcohol as a “remedy” makes sense only when there is no other way to lower pressure in an emergency situation.
Smoking is a major risk factor that threatens human health and which can be avoided. Smoking causes cancer as well as atherosclerosis. Many eye diseases (retinal vascular occlusion, maculopathy, cataracts, etc.) occur much more frequently and at an earlier age in smokers than in people who do not smoke. Older smokers also have a higher risk of developing elevated intraocular pressure compared with people who do not smoke, but there is no evidence that smoking is an independent (i.e. not associated with IOP) risk factor for glaucomatous lesions.
Despite the fact that marijuana has a lowering effect on intraocular pressure, its medical use has not been studied extensively enough yet so that it can be recommended as a therapeutic agent. There have been too few controlled studies on this issue, so you should carefully weigh all the advantages and disadvantages of long-term use of this substance.
Leisure and Sport
Regular physical activity is just as important for glaucomatous patients as having a proper rest and enough sleep.
Physical exercise tends to cause a reduction rather than an increase in intraocular pressure. However, patients with pigment glaucoma are sometimes the exception to this rule: they may experience an increase in IOP after physical exercise. However, even a patient with this particular form of glaucoma should be able to go in for sports. Prophylactic measures, such as laser iridotomy or pilocarpine instillation before exercise, can prevent IOP elevation. Sport is also recommended for patients with very low systemic arterial pressure to stabilize blood circulation.
Individuals who have already developed visual field defects should be aware of their condition. For example, because of these defects during a game of tennis, at certain moments patients may not see the ball, and during cycling they will not always notice the coming danger.
During swimming or diving in a relatively shallow water body, only minimal changes in intraocular pressure occur. Glaucomatous patients who are going to dive should first consult with an ophthalmologist. Patients with considerable damage to the optic nerve should refrain from underwater swimming.
There are no special observations concerning sauna. In glaucomatous patients IOP responds in the same way as in healthy people: it drops in the sauna and then returns to the initial level in about an hour. However, there is also no evidence that having a sauna is good for patients with glaucoma.
From the viewpoint of physics, intraocular pressure, measured by the doctor, is the difference between absolute intraocular pressure and atmospheric pressure at a certain moment. Thus, a rapid drop in atmospheric pressure causes a relative increase in IOP.
This is usually not a problem for a glaucomatous patient aboard an aircraft, since the artificially created atmospheric pressure inside the aircraft cabin generally compensates for the natural drop in pressure at a considerable height. The eye quickly adapts to the new condition. So, a moderate drop in atmospheric pressure will not cause an increase in IOP.
Another aspect that needs to be taken into account is the air quality in the aircraft cabin with slightly lower oxygen content at a considerable height and, as a result, less availability. But, again, cabin ventilation systems mainly provide passengers with a normal level of oxygen. However, glaucomatous patients with considerable circulatory disorders who fly frequently should discuss this issue with their ophthalmologist.
Playing wind instruments can cause a transient increase in intraocular pressure. Glaucomatous patients playing these instruments should discuss this issue with an ophthalmologist.
Those who wear contact lenses should not worry: these small optical devices do not affect intraocular pressure. In addition, IOP-lowering drugs can be prescribed for glaucomatous patients wearing contact lenses even in smaller doses. This is due to the fact that part of the drug gets into or under the contact lens, which creates a kind of depot from which the drug is constantly released. However, it should be remembered that some antihypertensive drugs can reduce corneal sensitivity. This increases the likelihood that an accidental injury that occurred when inserting the lens may remain unnoticed.
After years of wearing contact lenses, certain changes occur in the conjunctiva of patients. This means that if there is a need for antiglaucoma surgery some day, the risk of a probable closure of the fistula opening is higher.
However, administration of mitomycin C has reduced this risk. Some antiglaucoma medications may exacerbate the symptoms commonly known as dry eyes, making it more difficult to wear contact lenses.
So, patients with glaucoma, of course, can wear contact lenses, but should first consult their ophthalmologist.
Pregnancy and Breastfeeding
As a rule, intraocular pressure drops during pregnancy. This (as well as a moderate increase in IOP after menopause) indicates that sex hormones play an important role in regulating intraocular pressure. Since glaucoma is a chronic disease with very slow progression, the start of treatment can often be postponed until delivery.
If severe glaucomatous lesions are already present, or if intraocular pressure is extremely high, treatment during pregnancy is necessary and possible. The attending physician knows which medications that reduce IOP will be safe for the mother and the fetus, and select the necessary treatment.
Glaucoma prevention includes compliance with the following rules and recommendations:
- Avoid stressful situations, change job if necessary;
- Do not lift heavy weights, especially women and elderly people;
- If you are reading a book, doing any written tasks (lessons, etc.), working at a computer, watching TV, do it in good light, and if your eyes are tired, stop a while and let your eyes rest, 1 hour of work - 15 minutes break;
- Try to eat foods enriched with vitamins and minerals, limit the use of sugar and animal fats;
- Avoid excessive consumption of coffee, give up alcohol and smoking;
- When drinking water, don't drink more than 1 cup at a time;
- Don't leave various diseases without treatment, especially the upper body locomotor system disorders (cervical-thoracic) - kyphosis, lordosis, osteochondrosis;
- Don't wear tight ties, and don't press out your neck with any clothes, it worsens blood circulation in the head;
- Get enough sleep, follow the schedule - work / rest / sleep;
- Try not to use drugs without prescription, as many of them have a number of side effects;
- If you are being treated for glaucoma, just follow the regime of drop instillations;
- Visit an ophthalmologist regularly to prevent the development of glaucoma;
- Walk more.