Glaucoma is an eye disease that affects the optic nerve, whereby progressive damage occurs to the nerve fibers of the optic nerve. Treating glaucoma early is very important. An early diagnosis of glaucoma, caught during a regular examination at the ophthalmologist, is essential in order to begin treating glaucoma as soon as possible.
Normally the optic nerve contains a nice thick and pink rim of more than 1 million nerve fibers. In the case of glaucoma, the number of nerve fibers will decrease, and as a result the rim of nerve fibers in the optic nerve will become thinner.
Damage to the optic nerve is usually caused by increased eye pressure. The level of the eye pressure depends on the balance between the production and drainage of ocular fluids. Eye pressure that is too high (> 21 mmHg pressure) can develop when drainage is hindered.
On the other hand, not everyone with normal eye pressure is safe, because glaucoma can also develop under normal eye pressure. This is why an eye pressure measurement can sometimes lead to a false sense of safety. After an eye examination, your ophthalmologist will need to determine whether you potentially suffer from 'normal tension glaucoma'. Reduced blood flow of the optic nerve will play an important role. Additionally, not everyone with high eye pressure gets glaucoma. Your ophthalmologist will be able to determine whether the high eye pressure (ocular hypertension) needs to be treated.
There are two types of glaucoma: chronic glaucoma, which is the kind that occurs most frequently, and acute glaucoma. Although glaucoma usually occurs in people over the age of 40, it can actually arise at any age, even at birth.
Chronic glaucooma is a dormant disease and it often remains unnoticed for a long time because it is painless and at first there are no noticeable visual changes. At a later stage, it causes a progressive loss of the visual field. This begins at the visual periphery and slowly spreads out toward the center (tunnel vision). Eventually even the central visual acuity is affected. The loss of the visual field is permanent and irreversible. Without any treatment, this disease can lead to blindness.
Acute glaucoma requires swift medical intervention. The pressure in the eye increases suddenly. Usually the patient consults their ophthalmologist as an emergency because they are experiencing a lot of pain in the eye and around the eye socket. The eye is red, the pupil often widens, and the visual acuity is quickly murky due to clouding of the cornea. If this type of glaucoma is not treated quickly, it can lead to irreversible blindness.
Acute glaucoma occurs more frequently in women and in farsightedness or cataract. It is also important to be aware that some medications can trigger an attack of acute glaucoma. You can read this in the package leaflets of a number of medications, especially those that treat colds, diarrhea, depression and Parkinson's disease. This is always in regards to acute glaucoma. These medications have no affect on chronic glaucoma.
During your consultation at the eye clinic, your ophthalmologist will perform a number of standard eye examinations, among which a measurement of your eye pressure and an assessment of your optic nerve with a fundoscopy.
In the case that your ophthalmologist does determine that there are deviations in the eye pressure or if any structural damage is spotted, a further glaucoma screening will be carried out. A visual field examination will be carried out in order to check for any existing functional damage and to determine the extent of the damage. This examination is extremely important in order to identify and follow up on glaucoma.
Sometimes there is a structural examination of the optic nerve with an OCT (optical coherence tomography) device. This device is able to take high resolution images, including of the optic nerve by means of reflecting infrared light on the retina. It can measure the thickness of the retinal optic nerve layer which makes this device very valuable for following up on glaucoma. Glaucoma can be diagnosed and treated in the early stages.
Chronic glaucoma that has been caught and treated early by an ophthalmologist will usually not get any worse. The vision and visual field will remain stable because the pressure in the eye is reduced. In order to keep the eye pressure low, it is required to use eye drops on a daily basis. In some cases, eye laser treatment can be applied (microscopic holes are made in the iris) in order to keep the pressure stable. This eye laser treatment is very different from the eye laser treatment in order to see better without glasses or contacts. If there is not enough regulation of the eye pressure through either eye drops or with the laser eye treatment, then it is sometimes necessary to consider an operation. This allows for either a stent to be placed in the eye or a small opening to be made in the eyeball in order to allow the excess ocular fluid to easily drain under the conjunctiva.
Acute glaucoma is an emergency medical disease whereby an opening is made in the iris with a eye laser treatment (yag laser). This allows the excess ocular fluid to drain. The other eye is then treated preventatively.
Beginning at the age of 40, you should have a yearly visit with your ophthalmologist , especially if your family has a history of glaucoma. There are a number of other situations that increase your risk of glaucoma: