Cataract - what is it?

By Cristiano Antonino On Apr 9, 2023

Cataract is a phenomenon of opacification – partial or complete – of the crystalline, i.e. that part of the entire and transparent eye, located between the iris and the vitreous body, which allows the convergence and focus on the retina of the rays coming from different distances from external objects

The crystalline therefore covers a fundamental function for the eye: like a camera lens, it has the task of focusing on the retina the light coming from an object, a figure or a landscape that goes beyond the cornea.

Cataract: the symptoms with which it manifests itself

As it will be easy to imagine, the most common symptom with which the cataract manifests itself is the progressive blurring of vision.

The extent of the loss of vision will depend on the type and location of the opacification as opacities that develop with a more irregular appearance and centrally in the eye will tend to be more disabling.

Other symptoms commonly encountered with the onset of cataracts can be double vision, the appearance of colored halos around light sources, a temporary change in the refractive state of the patient’s eye, sometimes with a paradoxical improvement in a present refractive defect

Cataract: what are the causes and risk factors

The alterations of transparency of the crystalline constitute the condition known as cataract, where the opacities of the crystalline can affect the different layers.

Acquired forms are the most common.

The senile form, more common, is in fact linked to advancing age, which involves important changes at the level of the crystalline which becomes thicker, less flexible and less transparent.

Among the elderly over 65, 30% are affected by cataracts in one or both eyes, a symptom that aging is the main risk factor for the development of cataracts.

Other risk factors could be the intake of corticosteroids during pregnancy, which would cause congenital cataracts; iodine deficiency; diabetes mellitus; exposure to ionizing radiation; excessive exposure to UV and X-rays; chronic dehydration; galactosemia; genetic predisposition; female sex; uveitis; smoking and alcoholism. Finally, another secondary form can be the traumatic one.

Different types of cataracts

Based on what has been learned from the causes and risk factors, it can be deduced that cataract can be recognized in: senile cataract, drug cataract, traumatic cataract, congenital cataract and cataract resulting from other diseases.

Senile cataract

As already widely seen, the condition most at risk for developing cataracts is senility.

Therefore, in the absence of other previous pathologies, the cataract developed in old age is defined as “senile”.

When, on the other hand, the cataract develops between the ages of 40 and 60 in a healthy person, it is called a presenile cataract.

Drug cataract

Cortisone therapy taken for long periods, miotic drugs used in the form of eye drops or ointment can in the long run cause the onset of cataracts.

Traumatic cataract

As can easily be understood, traumatic cataracts are caused by traumatic physical or mechanical injuries suffered by the eye, such as perforating wounds or blunt trauma.

Congenital cataract

In rare cases, the disease can appear from an early age, or even from birth.

In cases like this, the causes can be the most varied: metabolic alterations suffered by the pregnant mother (dietary deficiencies, hypothyroidism, diabetes); metabolic disorders of the fetus; taking corticosteroids or sulfonamides; inheritance; infections contracted by the mother during the gestation period (rubella, toxoplasmosis, mumps, varicella, cytomegalovirus); childbirth before the end of 9 months; Marfan syndrome (syndrome involving a disorder of the connective system, particularly affecting the eyes).

Cataract from systemic diseases

Cataracts caused by a disease can appear at any time during an individual’s life, starting from the earliest years of age.

Generally, it is associated with diseases such as diabetes, skin disorders and other eye diseases.

People with diabetes are four times more likely to develop cataracts than healthy people.

In addition, the evolution of the disease in diabetic patients is generally quite rapid, with a much faster opacification of the lens than in non-diabetic patients.

Individuals suffering from skin disorders such as scleroderma, dermatitis, and poikiloderma may be prone to developing cataracts.

Even patients already being treated for other ocular problems (posterior uveitis, acute angle glaucoma, iridocyclitis, myopia, ocular tumors, retinal detachment) can suddenly develop cataracts, this is because the underlying pathologies act as a trigger for the development of the disease .

Cataract: the most adequate therapy

The only intervention that can be considered decisive when a patient develops cataracts is surgery for the removal of the now opacified crystalline lens and its replacement with an artificial one.

The operation is generally performed on an outpatient basis, after having made the patient aware of any risks deriving from the specific conditions of the patient.

Before the operation it will also be necessary to decide what the desired refractive result will be, so that the two eyes can be balanced with each other.

The actual intervention takes place thanks to local anesthesia, administered to the patient via anesthetic eye drops directly into the eye to be treated.

Only in rare cases where the specific conditions of the patient require it, is the route of general anesthesia chosen; this will still be a choice that the surgeon will carefully evaluate.

Another important choice that the surgeon will be asked to make will be that of the artificial lens

Almost always, the removal of the cataract is performed through phacoemulsification, a technique which consists in the crushing and consequent aspiration of the lens through the use of a probe.

However, the capsule that surrounds and holds the lens in place is not removed, so that it can subsequently serve as a support for the artificial lens.

Following cataract removal surgery, the patient may experience the sensation of a foreign body in the eye, resulting in discomfort, burning, excessive tearing, sensitivity to light sources, blurred vision and headache.

Within a few days, the patient will be perfectly able to return to his daily duties.