Glaucoma is a conditions characterized by the progressive damage of the optic nerve associated with a slow reduction of the visual field. If not treated on time, it may lead to irreversible blindness. High intraocular pressure is usually a very significant risk factor.

In general terms there is primary, open or narrow angle glaucoma, secondary glaucoma - when caused by other eye diseases - and congenital glaucoma resulting from an abnormal development of the aqueous humor outflow system.

In many cases, especially with open angle glaucoma, there are no symptoms. For this reason, it is very important to monitor intraocular pressure regularly, especially when the patient belongs to a high-risk group, namely, family history of glaucoma, more than 35 years of age, black race, diabetes, myopia, having received long-term treatment with steroids, or having sustained ocular trauma. With early detection and adequate management it is possible to prevent the reduction in the visual field size, which is irreversible. Unfortunately, this is the complaint of many glaucoma patients who look for help when the disease is already in an advanced stage.

When the disease manifests itself, it does so with headaches, tearing, red eyes, blurred vision and color halos similar to a rainbow around light sources, nausea and, occasionally, vomiting.

In congenital glaucoma, there is tearing, blepharospasm, photofobia and corneal edema early on, leading the eye to acquire a changing bluish appearance depending on the intraocular pressure level. In this situation, immediate consultation with the ophthalmologist is crucial, because it may be mistaken with an obstruction of the lachrymal system and treated as such, when in fact it requires emergency surgery. The clinical examination for glaucoma must be performed by an ophthalmologist, and includes, beside the routine checkup: Intraocular pressure measurement (tonometry), Visualization of the chamber angle (gonioscopy) and Assessment of the disc or the head of the optic nerve
Figure 1 is a schematic representation of aqueous humor outflow in an open-angle eye. Figure 2 represents the circulation of the aqueous humor in an eye with a narrow angle,
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Narrow angles may close as illustrated in Figure 3, giving rise to an acute glaucoma attack.

Until recently, glaucoma diagnosis was based on the measurement of intraocular pressure and the result of the perimetry studies.

Today, it is known that in order for a visual field damage to occur, at least 50% of the fibers that make up the layer of nerve fibers or the retina must be damaged. For that reason, standard automated perimetry is now reserved for late diagnosis and follow-up, and other functional tests are used including blue-yellow perimetry and other imaging methods using devices such as OCT (Optical Coherence Tomography), HRT (Heidelberg Retinal Tomographer), Gdx – optic nerve fiber analyzer, among others. These methods permit an early diagnosis and have become critical tools in the management of glaucoma.

Every glaucoma patient must be considered as an individual case because not all glaucomas of the same type respond in the same way. Consequently, treatment must be customized after a careful analysis of all the factors involved in the disease.

The treatment goal is to bring the intraocular pressure down to levels that are not harmful to the optic nerve, reducing the production of aqueous humor or improving its outflow.

The first step is to prescribe topical or systemic medications that are usually required for life. There are different types of medications including selective or non-selective blockers, carbonic anhydrase inhibitors, prostaglandin analogues, adrenergic antagonists, parasympathomimetics. In the event the expected result is not obtained, laser or conventional surgery is performed.

In newborns in whom there is a suspicion of congenital glaucoma, an examination under general anesthesia is mandatory. Congenital glaucoma always requires surgical treatment.