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Cataract

You noticed a decrease in your vision despite an appropriate correction? Colors appear dull and you need to increase the light sources to see well? With cataract refractive surgery, you could restore your vision and see without glasses at any distance.

What is cataract?

Cataracts are the number one cause of blindness in the world. In France, it affects more than 20% of the population over 65 and 60% of those over 85. Its prevalence is constantly increasing due to longer life span.

In the absence of surgical treatment, a patient with cataracts may experience a total or partial clouding of the lens, which causes a gradual and irreversible reduction in vision. In rare cases, it may appear in only one eye (unilateral cataract), but it generally affects both eyes (bilateral cataract). The visual discomfort it causes depends on both the intensity and location of the clouding of the lens.

What do we mean by lens?

The lens is situated behind the iris and is completely transparent. It is elastic and biconvex in shape. This form, or shape, depends on the ciliary muscle, which differs from person to person. It changes shape to allow vision at varying distances, and it is this that brings focus to the retina.

The lens is composed of a central core of protein fibers which is surrounded by a transparent and elastic envelope: the capsule. In this small “pouch”, there are two parts which we can identify anatomically: the anterior capsule and the posterior capsule. In a patient with cataracts, the lens loses its transparency and flexibility and also changes color according to its severity (brown, red, white, etc.).

Light can no longer be transmitted effectively to the retina; therefore, the image produced is no longer clear. When the cataract is large, it can be seen by the naked eye, in the pupil.

What are the cataracts symptoms?

Symptoms most often appear with age, although cataracts can occur at any time of life. Cataracts are painless and are characterized by purely visual symptoms, the main one being a gradual decrease in vision, sometimes over several years, despite an appropriate correction with glasses or lenses.

Progressive clouding of the lens can manifest as:

  • Blurred vision
  • A decrease in visual acuity
  • Impaired color vision (yellowing, or difficulty distinguishing close colours)
  • Glare, halos around light sources which can make driving at night difficult
  • Optical aberrations
  • A decrease in the vision of contrasts
  • The need to increase the light sources for certain activities (reading, sewing…) The impact of these symptoms on daily activities can become significant and very bothersome.

How to diagnose cataract?

Cataract screening is typically done by:

  • A visual acuity test
  • A slit-lamp examination (biomicroscope)

At the Bellecour Vision Clinic, we specialize in cataract screening, we don’t just test visual acuity, but we also take visual quality into account. To achieve this, we assess the sensitivity to contrasts at all spatial frequencies as well as the absorption and scattering of light by the lens using the “Visiometrix HD Analyzer”.

We check the density of the lens using OCT imaging, and we also evaluate aberrometric changes related to cataracts. During the proposed preoperative assessment, we will also verify that the other anatomical and physiological structures of the eye are healthy to optimize the results of the surgery and reduce complications.

We will check:

  • The condition of the lens zonules (fibers that hold the capsular bag)
  • The state of the retina
  • The state of the optic nerve
  • The state of the Meibomius glands
  • The state of the tear film and the regularity of the corneal surface
  • The corneal topography
  • The condition of the corneal endothelial cells

Lastly, we will perform an eye biometry, which collects the dimensions of the eye to accurately calculate the power of the custom-made implant, which will replace your lens and give you perfect vision without glasses. The purpose of this comprehensive assessment (which lasts approximately 2 hours) is to operate under the best possible safety conditions and to offer you the best possible visual result.

What causes cataract?

Most cataracts are caused by normal changes in your eyes as you get older. When you’re young, the lens in your eye is clear. Around age 40, the proteins in the lens of your eye start to break down and clump together. This clump makes a cloudy area on your lens — or a cataract. Over time, the cataract gets more severe and clouds more of the lens. Your risk for cataracts goes up as you get older.

You’re also at higher risk if you:

  • Have certain health problems, like diabetes
  • Smoke
  • Drink too much alcohol
  • Have a family history of cataracts
  • Have had an eye injury, eye surgery, or radiation treatment on your upper body
  • Have spent a lot of time in the sun
  • Take steroids (medicines used to treat a variety of health problems, like arthritis and rashes)

Are there different types of cataracts?

Yes. We will classify the different types of cataracts according to the anatomical zone of the lens in which the cataract appears.

  • Nuclear cataract:
    the opacities are located in the nucleus of the lens. Its evolution leads to growing myopia and sometimes the splitting of images.
  • Cortical cataract:
    the opacities are located at the periphery, on the cortex of the lens.
  • Cortico-nuclear cataract:
    all the layers of the lens are more or less equally clouded. It is the most common form of senile cataract. The patients feel they need more light to see.
  • Subcapsular cataract:
    the opacities are located under the posterior or anterior capsule of the lens. This cataract gives the sensation of having a veil before the eyes and of being dazzled. The different forms of cataracts are also named according to their cause of occurrence.
  • Senile cataract:
    it is the most common cataract. It appears with ageing, at around 65/70 years old, although it can affect much younger individuals. The nucleus and cortex are opacified (cortico-nuclear cataract). It often affects far vision first before interfering with near vision.
  • Traumatic cataract:
    it often occurs in young people and children following a force trauma (e.g. a punch, champagne cork, ball sports: watch out for badminton and squash!). It is typically posterior subcapsular. It can also follow an eyeball injury or the introduction of a foreign body into the eye. It can sometimes appear long after being hit.
  • Pathological cataract:
    they include cataracts alongside another ocular pathology: strong myopia, chronic uveitis (they are called “complicated cataracts”) or to a general metabolic pathology such as insulin-dependent diabetes (posterior subcapsular cataracts) for example. There may be iatrogenic cataracts due to prolonged use of certain drugs (corticosteroids) or in the aftermath of radiation therapy.
  • Congenital cataract:
    it can be present from birth (0,03% of births) and requires early management to avoid amblyopia.
  • Secondary cataract or capsular fibrosis:
    it occurs frequently after cataract surgery. It is not considered a complication of the first operation. It is due to the clouding of the lens envelope within a few months or years after the primary procedure. It is easily diagnosed with a slit lamp examination and treated at once with the YAG laser (capsulotomy).

How does cataracts evolve?

Without surgery, cataracts can cause blindness.

How to cure cataracts?

The only treatment for cataracts is surgery. It is the most widely performed procedure in France, with nearly 850 000 procedures per year. When the beginning of a cataract is detected, simple ophthalmological monitoring is necessary. It is entirely the patient’s decision as to when they feel their quality of vision has deteriorated to a level that they no longer wish to tolerate. At this point, you may want to consider surgery.

The surgical treatment aims to:

  • Clean the clouded lens
  • Insert an artificial lens (intraocular implant made of synthetic material), while retaining its natural envelope (capsule) which will serve as a support for the implant.

This operation is definitive, and the implant is made to last for life.

When to have cataract surgery?

There is no recommended age for having the operation. You have to think about the operation as soon as you are significantly hampered in your daily activities despite an appropriate correction. Do not wait until the lens is too hard and too opaque. If the average age of the cataract operation is between 60 and 70 years in France, some people are embarrassed much earlier.

In addition, the indication will also depend on the type of cataract you have. An active patient with cataract will have surgery quickly. Apart from very rare exceptions, there is no urgency to operate. Some elderly people whose daily life does not require excellent eyesight cope very well with this pathology. On the other hand, if cataracts prevent you from leading a normal life (driving, reading, etc.) or restrict your leisure activities (reading, sewing, etc.), you should not hesitate to consult.