The time when glaucoma diagnosis was based solely on the measurement of intraocular pressure has passed. An increased intraocular pressure (>21mmHg) does not by itself indicate glaucoma; likewise, low intraocular pressure (<21mmHg) does not exclude glaucoma (normal pressure glaucoma).

Diagnosis is done by assessing the person's history and factoring in the following ophthalmological tests:

    Visual field test (perimetry)
    Digital (computational) imaging of the optic nerve



Tonometry measures the interior pressure of the eye.Drops are used to anesthetize the eye. Next, the doctor uses a special machine that measures the eye pressure (Image 6). Besides the traditional Goldmann tonometer, we also use advanced automatic electronic tonometers (Canon), specialized in treating glaucoma patients (Image 7).



Ophthalmoscopy (Assessment of the optic nerve and the nerve fibers)

The examination of the optic nerve is performed by the ophthalmologist using the ophthalmoscope. With this instrument we can measure the size of the cupping of the optic nerve. A cupping larger than normal (Image 10) or a cupping of different size between the two eyes can lead to a glaucoma diagnosis.

If the eye pressure is not in the normal range or if the morphology of the optic nerve is unusual, then two special tests should be done. These testing methods are called perimetry and gonioscopy.



Gonioscopy is a painless eye test, which checks if the angle, where the iris meets the cornea, is open or closed, indicating the existence of open or closed angle glaucoma.



The perimetry test is also known as visual field test (Image 11). During this test, you are asked to look straight forward and track a light. This helps us form a “map” of your vision (Image 12). With this test, we record the percentage of nerve fibers that have been damaged by glaucoma. It is based on the ability of the patient to see light in every area of the retina. This test is necessary and must be done regularly, in order for possible changes in the field of view to be diagnosed and to track potential aggravations (scotomas).


Digital (computational) imaging of the optic nerve

Two new imaging methods for the optic nerve have been recently made widely available. These are Heidelberg Retinal Tomography (HRT 3) and optical coherence tomography (OCT). HRT 3 scans the retinal surface and the optic nerve using a laser beam. It then forms a 3D topographic imaging of the optic nerve head. It also measures the thickness of the nerve fiber layer (Images 13, 14, 15 and 16).



OCT makes use of a technique called optical coherence tomography, which creates images using special light rays. OCT can create a map of the outline of the optic nerve head and its cupping, as well as measure the thickness of the nerve fiber layer (Image 17).




Corneal thickness is important, since it can disguise an accurate measurement of the pressure, resulting in treating a condition that might not even exist. Actual intraocular pressure can be underestimated in patients with thinner cornea (thinner central cornea thickness) and overestimated in patients with thicker cornea. A pachymetry test is a simple, quick, painless method to measure corneal thickness (Images 18 and 19). Using this measurement the doctor can better calculate intraocular pressure, reach a more accurate diagnosis and make a treatment plan suitable for this particular situation. The procedure lasts about half a minute to measure both eyes.



Is glaucoma the main cause for blindless?

Glaucoma can lead to blindness if it is not treated. Unfortunately, about 10% of the people who will receive proper treatment will suffer loss of vision.


There is no cure for glaucoma yet

Glaucoma is not curable and vision loss cannot be restored. With the help of medication and/or a surgical procedure, it is possible to halt any further loss of vision. Given that glaucoma is a chronic condition, it should be monitored for the rest of the patient's life. Diagnosis is the first step to retain your vision.



Causes for glaucoma

Glaucoma treatment






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