Glaucoma

Glaucoma includes a set of ocular changes, such as:

Reduction of the visual field
Increased intraocular pressure
Excavation of the optic disc

The first alteration to appear is the increase in intraocular pressure, which can remain constantly high for a long period or alternate with periods in which it also assumes normal values. An eye pressure greater than 20-22 mmHg is considered pathological.

Ocular hypertension, in the second stage, is associated as a direct consequence with damage to the optic disc, which takes on a typical appearance (excavated and pale papilla).
Nervous atrophy leads to the third stage in which there is a reduction in the visual field, initially peripheral; this damage is what is felt by the patient as the first symptom (decrease in vision), as the simplest glaucoma is generally not accompanied by pain in the phase of high eye pressure.
Glaucoma is a pathology that cannot be solved, but by intervening promptly it is possible to stabilize it through medical therapy or, in more complicated cases, with surgery.
For this reason it is important to follow the instructions of the ophthalmologist, showing up for every check-up and carrying out the required tests, such as the visual field test.

Insights into Glaucoma

Glaucoma can be divided into primary and secondary; in the first case the pathology can be traced back to an anatomical-functional alteration of the eye, in the second case the pathology is linked to a pathological event different from those which are the ocular hydrodynamic processes.

In the context of primary glaucoma, the most frequent cause of glaucoma is damage to the trabecular meshwork, i.e. the area between the iris and cornea where the aqueous humor is filtered. The impaired filtration of the aqueous humor results in an increase in intraocular pressure which causes compression in the vascular system.
Simple glaucoma occurs mainly in adulthood, in the same percentage between females and males.
It occurs in both eyes, although in some cases not at the same time; it is a pathology with hereditary characteristics.
Untreated glaucoma can cause complications such as cataracts and, in elderly subjects, thrombosis of the central retinal vein.
It is therefore clear that the prognosis of the disease also varies depending on the time of onset.
However, it is important to underline that the individual manifestations described above, not present at the same time, do not determine the diagnosis of glaucoma. The correct approach, especially after detecting high intraocular pressure during a check-up, would be to carry out periodic checks to monitor the pressure and its possible evolution.
The treatment of glaucoma involves the use of drugs (eye drops or ointments) that aim to lower eye pressure. More rarely, subconjunctival injections are performed.
The parasurgical treatment primarily involves the use of argon laser, which is a photocoagulative treatment that intervenes on the trabecular meshwork in order to widen its mesh and promote the outflow of aqueous humor.
In the last stage, surgical treatment (trabeculectomy) is taken into consideration if previous therapies do not have beneficial effects.
It is a technique that allows, with the creation of a fistula that connects the Schlemm canal with the trabecular meshwork, allowing the outflow of the aqueous humor. What has just been described refers to primary trabecular block glaucoma, the most widespread.
Primary glaucomas caused by alterations to Schlemm’s canal or the angular area are also found less frequently.
Secondary glaucoma, however, can be caused by generalized inflammation, trauma or alterations of the ocular circulation (secondary glaucoma due to increased pressure in the episcleral vein is known). A rare type of glaucoma, congenital glaucoma, is present from birth and manifests itself with very high eye pressure caused by hereditary disorders.
Pharmacological and surgical therapies are also different, depending on the type of glaucoma.
The drugs used can be, depending on the case, dehydrants, drugs with antienzymatic or anti-inflammatory action, or drugs that induce morphofunctional changes in the lens or in the ciliary body or in the iris. Surgical interventions are also different, depending on the type of glaucoma to be treated; in fact, it is possible to intervene not only on the trabecular meshwork, but also on the iris, the sclera or the vitreous body.

It is useful to point out to the patient that a low-fat diet and the elimination of caffeine-containing drinks, as well as foods containing monosodium glutamate, are habits that assist pharmacological therapy.