The silent blindness disease
Glaucoma is an optic neuropathy which affects the papilla or optic nerve and causes other specific visual field defects, generally as a consequence of high intraocular pressure, but not always.
It is a disorder with a series of symptoms that cause degeneration of sensitive eye tissues, retinal nerve fibers and specifically of the optic nerve, which carries visual information to the brain. In most cases this is a consequence of high intraocular pressure.
If aqueous humor drainage from the anterior chamber of the eye is limited, intraocular pressure will raise, giving place to irreversible damage of the optic nerve causing permanent vision loss.
- Aged 40 and over
- People with severe myopia, diabetes or family history of glaucoma
- People taking corticosteroids for long periods of time
- African-Americans, especially after the age of 35
- People who have had an ocular traumatism
Glaucoma is often diagnosed in advanced stages, as symptoms do not usually appear until then.
This is why it is so important to have regular ophthalmological checkups, especially those who are at risk. If glaucoma is diagnosed in early stages, it generally responds well to treatment and it is possible to reduce irreversible damage.
In some cases, especially if there is a rapid increase in intraocular pressure, the following symptoms may be experienced:
- Gradual loss of peripheral vision (tunnel vision)
- Periocular pain when moving from a dark area to a well illuminated area
- Headache and eye redness
- Nauseas and vomiting
- Vision of halos
- Blurred vision
There are three basic tests for detecting glaucoma:
- Tonometry - Intraocular pressure (IOP) measurement
- GDX and OCT - Optic nerve and retina inspection
- Computerized or automated perimetry - Visual field examination
Genetic test - Nowadays, glaucoma can be prevented before it appears if genetic tests that measure the predisposition of each patient to develop a pseudoexfoliation syndrome (PXF) are performed. 50% of patients who have this syndrome end up having glaucoma. The test is carried out using a saliva sample in order to analyse a set of high reliability biomarkers.
Glaucoma management involves a variety of therapeutic options which can be grossly divided into topical medication which reduces aqueous humor production or favors its drainage, and surgical treatments.
Among surgical treatments, the following techniques should be noted:
- MIGS (Minimally Invasive Glaucoma Surgery): Nowadays, it represents one of the most significant advances in glaucoma surgery. It is indicated in patients with mild to moderate ocular hypertension as an adjuvant to topical medication in order to reduce its dosage or even as a substitute of it, as chronic use of these eyedrops produces uncomfortable side effects such as dry eye syndrome. Therefore, it does not only allow an improvement in managing ocular hypertension, but also in the patient’s quality of life.
- Laser therapy: The trabeculum, where aqueous humor drainage takes place, is irradiated with laser pulses in order to favor it.
- Filtering surgeries (trabeculectomy and deep sclerectomy): These techniques allow aqueous humor to exit the eye’s anterior chamber.
- Drainage devices: These devices are used in advanced glaucoma or when other techniques are not indicated or have failed.
There is not a single type of glaucoma, so treatment must be adapted to each type of glaucoma and other characteristics of the eye.Dr. Luis Alonso | Ophthalmologist