What are the different types of glaucoma

useful information

How does glaucoma develop?

Glaucoma (glaucoma) is damage to the optic nerve (optic nerve neuropathy). In the vast majority of cases, the cause is increased eye pressure. The pressure inside the eye ensures the round shape of the eyeball and presses the outer layers of the eye firmly against the outer wall, which is central to the visual function. The aqueous humor, a fluid that is formed in the ciliary body, is responsible for maintaining intraocular pressure. If the equilibrium between production and drainage of the aqueous humor is disturbed, this can lead to an increase in pressure and associated pressure damage. The risk factors for the development of glaucoma therefore correspond to those of too high intraocular pressure.

Symptoms

Unfortunately, the increase in pressure in the eye is symptom-free for a long time. It is therefore possible that irreversible damage to the optic nerve is already present when the first symptoms appear. Early detection is therefore central and takes place through regular check-ups when risk factors are present and at an older age. Often the affected patient first notices a visual field defect (scotoma) at the edge of the visual field. This usually occurs gradually due to the increasing pressure damage to the optic nerve. However, it can also lead to an acute attack of glaucoma, which is an absolute emergency situation. Symptoms include sudden deterioration in vision, a hard eyeball, severe headache and eye pain, vomiting, nausea, and irregular heartbeat.

Forms of glaucoma

Different forms of glaucoma are identified by pathogenesis. In order to understand the origins of the various types of glaucoma, one must remember the drainage path of the aqueous humor. After the aqueous humor has been secreted from the ciliary body into the posterior chamber of the eye, it flows past the lens through the pupillary angle into the anterior chamber. Most of the aqueous humor flows from there via the trabecular system into Schlemm’s canal. A bypass of this path is the direct drainage into the veins of the dermis (sclera).

Open-angle glaucoma

The most common form of glaucoma is open-angle glaucoma. Here, the drainage via the trabecular system and Schlemm’s canal is disturbed. The reason for this is usually a degenerative process, which is why open-angle glaucoma occurs more frequently in old age. An inheritable component is also known.

Angle closure glaucoma (angle closure glaucoma)

In angle-closure glaucoma, as the name suggests, the pupillary angle is blocked. The aqueous humor cannot get into the anterior chamber and the pressure increases.

Normal pressure glaucoma

The classic symptom of glaucoma, increased intraocular pressure, is not present in normal pressure glaucoma. The optic nerve damage is caused by a circulatory disorder, so it is a vascular neuropathy.

Congenital glaucoma

Congenital (congenital) glaucoma is a special form insofar as it becomes manifest at a young age. The drainage disorder has been present since birth.

Secondary glaucoma

Secondary glaucoma occurs as a result of an underlying disease or other damaging influences such as trauma or medication.

Diagnosis

The ophthalmologist will perform several tests to diagnose glaucoma. The measurement of intraocular pressure by means of tonometry is certainly central. The fundus and thus the optic nerve can be assessed in fundoscopy and slit lamp examinations. The field of view is examined in perimetry. The findings of these examinations allow the diagnosis of glaucoma.

therapy

Various therapeutic approaches are available. The easiest way to do this is surely to use eye drops that lower eye pressure. However, these must be used regularly in order to achieve an effect and are ineffective in normal pressure glaucoma. Oral drugs are also available, but these often have side effects. Alternatively, surgery can be performed to restore the aqueous humor outflow. Laser treatments are also very effective.

Summary

Glaucoma is a serious disease that, if left untreated, can lead to blindness. As little or no symptoms are noticed for a long time, check-ups are essential. For detailed advice and examinations, contact your ophthalmologist in the Zurich Oberland.

This article corresponds to the current state of science

Green Star (Glaucoma) Day Clinic Zurich Oberland2017-08-04AZO - Eye Clinic Zurich Oberland