Glaucoma

Glaucoma is one of the most common causes of blindness and comprises a group of diseases that cause progressive and irreversible damage to the optic nerve. This structure is key to vision since, through it, the images captured by the retina (converted into nerve impulses) are transmitted to the brain so that it can interpret them and generate vision.

Visual impairment

Glaucoma is a chronic disease caused by the early death of retinal ganglion cells, whose axons form the optic nerve.

As a consequence, the optic nerve loses its functionality. If the disease is not treated in time, the patient’s field of vision is reduced.

Most common risk factor

The main risk factor that can trigger glaucoma is ocular hipertension. This condition usually occurs because, the aqueous humor (fluid that bathes the inner eye) does not drain properly and builds up, putting excessive pressure on the optic nerve and causing a “stress” that it cannot withstand.

Other risk factors

However, there are people with elevated intraocular pressure who do not develop glaucoma and patients with normal values (less than 21 mm Hg pressure) who, on the contrary, develop the pathology.

It must be taken into account that glaucoma is not only the consequence of a “mechanical” defect in the drainage system of the aqueous humor, but it is also a multifactorial disease whose origin is still little known. Research is being carried out in this field and it is suspected that vascular problems may be associated with cases of glaucoma with normal intraocular pressure, since the blood vessels inside the eyeball are among the finest in the body and therefore particularly fragile.

Hereditary factors

On the other hand, genetic predisposition is a major factor in certain types of glaucoma, such as open-angle (familial) primary glaucoma – the most common – or congenital glaucoma – which appears in the first months of life – and juvenile glaucoma.

After the age of 40, it is important to undergo a complete eye examination every one or two years. If eye pressure can be reduced in the early stages of glaucoma, the development of the disease can be stopped and vision can be protected.

The importance of early diagnosis

The key to avoiding irreversible damage to the optic nerve caused by glaucoma is the early diagnosis of the disease, with the aim to control it before it continues to progress. Given that in most cases it does not cause symptoms until advanced stages of the pathology, every two years check-us are recomended for people from the age of 40, as, from that age the degenerative process of the eye is activated and the incidence of glaucoma begins to increase.

Regular check-ups

Check-ups are specially recomended on people with any of the following risk factors:

• Age (over 60)
• Family history of glaucoma
• Ocular hypertension
• Myopia or high myopia
• Other eye diseases, such as corneal, retinal, uveitis, etc.
• Ocular traumas
• Narrow iridocorneal angle (formed by the cornea and sclera with the iris)
• Black or Asian race

Last generation equipment

Advances in diagnostic equipment have helped to detect glaucoma at very early stages.

A correct diagnosis is essential, including a funduscopic exploration as well as an optical nerve examination.

The following tests are usually performed:

• Posterior Optical Coherence Tomography (OCT) and HRT, to detect alterations in the posterior areas of the eye (retina and optic nerve)
• Tonometry or intraocular pressure measurement
• Pachymetry, which allows the measurement of the thickness of the cornea
• Gonioscopy, to correctly explore the iridocorneal angle
• Campimetry, to evaluate the visual field