Secondary glaucoma is a group of diseases that affect the optic nerve. As a rule, this condition leads to increased intraocular pressure (IOP). This disease occurs as a result of an already suffered illness or eye injury. . Glaucoma is one of the main causes of blindness in the elderly and often goes unnoticed.
Although glaucoma is considered an age-related disease, a person may be genetically predisposed to glaucoma due to concomitant factors. But at the same time, it is not at all necessary that the pathology can develop if it is diagnosed in one of the family members.
Depending on the nature of the disease, doctors distinguish the following forms of glaucoma:
- Primary, that is, one that is caused by a genetic predisposition, a congenital pathology of the eye, and not by some other ophthalmic disease. Often the cause of problems with the outflow of intraocular fluid and an increase in IOP are transferred intrauterine infections (rubella, mumps, toxoplasmosis);
- Secondary glaucoma is a complication against the background of another pathology of the organ of vision, in which intraocular pressure rises, the optic nerve is damaged, as well as diabetes mellitus.
Who is at risk for developing the disease?
Most often, the development of secondary glaucoma affects people over 60, but it can be encountered at 45 and 35 years. If one of your relatives has been diagnosed with this pathology, you should especially carefully monitor the health of the eyes. Since the pathology is directly related to pressure, it is more common among people with diabetes and hypertension (high blood pressure).
How does the disease manifest itself?
The most common signs and symptoms of secondary glaucoma include:
- Pain syndrome. Constant headaches and eye pain;
- The appearance of rainbow circles or a feeling of fog before the eyes;
- Narrowing of peripheral (lateral) vision;
- Decreased clarity of vision (violation of accommodation, or focusing, deterioration of visual functions).
Often with secondary glaucoma, anomalies in the structure of the eyes (small cornea, persistent vitreous body), refractive errors can be combined. For example, myopia is most often caused by the fact that the eyeball has grown too much in size. Increased volume implies greater stretch with increased IOP, which increases the likelihood of optic nerve degeneration. With farsightedness, on the contrary, the eyeball may be smaller. If the anterior chamber of the eye is compact, this predisposes to obstruction of aqueous humor outflow tracts.
Let us dwell on secondary glaucoma and analyze the causes of its development. Usually, several combined factors contribute to the appearance of glaucoma at once, most often these are:
- Recurrent inflammatory processes of a viral or bacterial nature (conjunctivitis, scleritis, uveitis, chronic keratitis) affect the drainage system of the eyes, which increases intraocular pressure;
- Dislocation (wrong position) of the lens, which disrupts the outflow of intraocular fluid;
- Cataract. With this disease, the anterior chamber of the eye decreases and a lens block occurs, in connection with which the IOP rises;
- Thrombosis of the central retinal vein leads to ischemia and neovascularization of retinal vessels (their growth) in the anterior part of the eye;
- Eye injuries – wounds, burns lead to ingrowth of the epithelium, excessive accumulation of moisture;
- Malignant neoplasms in different parts of the organ of vision or its appendages, such as retinoblastoma or melanoma, also lead to an increase in IOP.
As we can see, the disease is characterized by a wide variety of causes and clinical manifestations.
Secondary glaucoma are:
- Uveal ( post-inflammatory ), when the cornea, sclera, choroid of the eye is affected;
- Phacogenic – as a rule, this is the result of a complication of a cataract, as well as other pathologies of the lens with a violation of its structure or localization;
- Vascular, that is, associated with thrombosis or a persistent increase in pressure. They are divided into neovascular (with the growth of pathological vessels in the structures of the angle of the anterior chamber with insufficient oxygen supply to the tissues of the eye – hypoxia) and phlebohypertensive (in violation of the outflow of blood through the episcleral veins);
- Post-traumatic due to injuries or surgical interventions;
- Degenerative – due to uveopathy , Fuchs anomaly and iridocorneal endothelial syndrome ;
- Neoplastic (in the presence of tumor processes).
As secondary glaucoma progresses, four stages of the disease are distinguished:
- I – initial stage. It is characterized by periodic jumps in IOP and the appearance of depressions (excavations) on the optic nerve head. The patient may not feel any changes and be unaware of the development of the disease;
- II – advanced stage. The excavation becomes more pronounced, reaches the edges of the disc, the boundaries of the visual field narrow by 10 or more degrees, but the symptoms are still invisible;
- III – advanced stage. Peripheral vision is impaired, the view is limited on all sides, less than 15% of the focus point. Closing one of the eyes, the patient has difficulty with orientation in space;
- IV – terminal stage. At this stage, visual functions are irretrievably lost, the patient can only distinguish light from shadow.
Diagnosis and treatment of secondary glaucoma
The most severe complication of advanced glaucoma is blindness due to atrophy of the optic nerve. Since the disease is considered age-related, patients over 40 years of age should undergo annual ophthalmological examinations for the timely detection of glaucoma. It is important not to miss the moment when vision can still be saved. To make an accurate diagnosis, the ophthalmologist will conduct the following examinations:
- Visiometry – assessment of visual acuity with and without correction;
- Tonometry – measurement of intraocular pressure;
- Biomicroscopy – examination with a slit lamp;
- Refractometry to check the refractive power of the eye
- Ophthalmoscopy to check the condition of the fundus.
If the specialist detects ophthalmohypertension , then he will additionally conduct a study of the visual fields (perimetry), gonioscopy and pachymetry , that is, he will study the structure of the angle of the anterior chamber of the eye and measure the thickness of the cornea. The data obtained may be the basis for suspecting glaucoma in the patient and re-examination after 2-4 weeks. In order to confirm or refute the diagnosis, it may be necessary to perform tonography , daily pressure measurements, coherence tomography. Also in this case, you will need to consult a glaucomatologist – a highly specialized specialist in the treatment of glaucoma.
The key point in the treatment of secondary glaucoma is the treatment of the underlying disease that led to its development, that is, hypertension. When secondary glaucoma is detected, eye drops are used that reduce pressure in the vessels and tension (increased ophthalmotonus ). Finding the right medication can sometimes take a long time. A couple of weeks after the appointment and the start of use, the doctor evaluates the effect. If it is not available, it replaces the drug or supplements it with another.
For successful treatment of secondary glaucoma, the patient must carefully follow all recommendations, especially before control pressure measurements. If this is not done, it will be impossible to track the dynamics and understand whether the disease is progressing or not. If you often forget to take your medications, it’s worth setting reminders on your phone according to the schedule your doctor has set, or setting an alarm. In addition to conservative therapy, you may be prescribed vascular therapy to improve circulation.
Prescribing drugs may not be enough to stabilize the pressure. In some cases, surgical treatment of secondary glaucoma is recommended. The operation is aimed at restoring the circulation of the eye fluid, but is not able to restore vision. The laser is used to:
- Laser iridectomy is the creation of an artificial hole in the iris to improve fluid circulation and normalize pressure. The operation is performed in a few minutes, under local anesthesia on an outpatient basis using a YAG laser. This method has a number of limitations and contraindications, the procedure is not performed in case of damage or clouding of the cornea, pronounced edema;
- Laser trabeculoplasty (partial removal of the trabecular meshwork ) effectively shows itself in stages I and II of glaucoma, improves the functioning of the drainage system and restores the outflow of intraocular fluid.