Cataracts

Cataracts are one of the most common causes of a loss of vision and are due to a loss of transparency of the crystalline lens, the eye's natural lens.

Naturally and due to ageing, the crystalline lens loses its transparency which translates into reduced visual acuity. Although the majority are related to age, there are other types like congenital cataracts (present from birth), secondary to certain diseases (uveitis, diabetes), medication (corticosteriod) and eye trauma. 

Cataracts normally develop slowly, which is why the symptoms appear gradually:

• Blurred or cloudy vision in short-sighted individuals.

• Glare from sunlight, lights or car headlamps at night.

• In some cases, cataracts cause short-sightedness, which is why they may improve close-up vision.

A consultant can assess whether a patient is experiencing cataract onset, which is why it is good to have regular check-ups, whether you do or do not use glasses or contact lenses.

Cataracts can be classified according to their cause or the area of opacity in the crystalline lens.

Senile cataracts

Senile cataracts are the most common and they are age-related.

Metabolic cataracts

Metabolic cataracts are associated with metabolic illnesses. The most common is diabetes mellitus.

Congenital cataracts

Congenital cataracts exist from birth or develop over the first few months of life. They may be associated with genetic conditions or a disease suffered by the mother during pregnancy like rubella or toxoplasmosis.

Traumatic cataracts

Traumatic cataracts occur after experiencing eye trauma.

Toxic cataracts

Toxic cataracts are associated with chronic use or abuse of some drugs or toxic substances, corticoids being the most common causal element.

Furthermore, depending on the area affected by the opacified crystalline lens, we can distinguish between:

Nuclear cataracts

Nuclear cataracts, in which the nucleus or centre of the crystalline lens in particular becomes opaque. A nuclear cataract usually evolves slowly and affects farsight more than nearsight. They are the most common and are usually associated with age.

Cortical cataracts

Cortical cataracts are cataracts where the cortex or lens cover becomes opacified. They are less common than nuclear cataracts and affect nearsightedness.

Posterior subcapsule cataracts

Posterior subcapsule cataracts, which develop in the outermost layer of the crystalline lens: the posterior lens capsule. This type usually progresses quite quickly and a common symptom is glare.                  

Careful observation and description of cataracts in a slit-lamp exam is key in drawing up an ophthalmic clinical history for each patient. On one hand, it enables the progression of the cataract from one visit to the next to be evaluated. On the other hand, the type and grade of the cataract determine the most appropriate choice of surgical technique used to remove it, and warn of the possible intraoperative risks inherent to each type.

The definitive treatment is still surgery. 

Cataract surgery is currently a quick and pain-free process. It is highly effective and carries few risks. The operation involves aspirating the content of the opacified crystalline lens and replacing it with an intraocular lens.

Intraocular lenses are under constant technological evolution, both in terms of their design as well as the material used to make them. There are currently different types of intraocular lenses: 

• Monofocal intraocular lenses
  They correct distance vision, but the patient needs glasses to see up close.

• Multifocal intraocular lenses
  They provide vision at different distances: near, medium and far depending on the lens model. 

Postoperative recovery is quick and normal vision is restored.

The femtosecond laser can be used in cataract surgery.

The surgeon will decide on the best option after assessing each case individually, depending on the expectations and anatomical and functional condition of each individual.