Sunday , March 26 2023

Cataract: Types of lens used

Cataract is derived from the Latin word Cataracta, which means waterfall. This name may have been given in lieu of the fact that the proteins in the eye lens break down, which makes them cloudy. Cataract is an eye disease in which the clear natural lens of the eye becomes opaque leading to a decrease in vision.

It is the most common cause of blindness worldwide, specially the developing countries.

It is not a tumor or a contagious condition and does not travel from one eye to another. It is rarely noticed early on as its growth is slow and rarely catastrophic. Cataracts can be age related, congenital (by birth, childhood), due to a per-existing ailment (diabetes etc.), due to smoking, obesity, hypertension, family history, trauma (injury related) or due to exposure to harmful radiations.

Cataract can be categorized into three main categories:

#1 Subscapular cataract

It begins as an opaque area at the back of the lens blocking the light from reaching the retina.

#2 Nuclear cataract

This affects the center of the lens mainly due to ageing. The lens can gradually become densely yellow and later brown, which can render a person incapable of distinguishing shades of colors.

#3 Cortical cataract

This begins as whitish, wedge like streaks from the edges of lens and moves to the center blocking the light from passing the lens. Symptoms can be blurred foggy vision, colors looking faded & discolored, noticingglare or halos around light, Frequent eyeglass prescriptions, Double vision in one eye, Near sightedness, etc. Cataract can be detected by a comprehensive examination by an eye care professional.

Some of the tests are:

  • Visual acuity – It’s a basic test to examine the vision at various distances.
  • Dilated eye – Drops are poured into the eyes to widen the pupils while a professional examines the retina.
  • Tonometry – It is an instrument, which measures the pressure inside the eyes by using numbing drops The only effective treatment for cataract is surgery but one should consult their doctor before deciding to go for the procedure as most doctors recommend the operation as an option only when the daily life of the patient starts getting effected. The cataract surgery involves the affected lens to be removed and replacing it with a clear lens, artificial in nature, which are also known as intraocular lens. This lens then becomes a part of the eye permanently. There are majorly two kinds of surgeries,
  • Phacoemulsification & Extra capsular – Phaco is the most common method used nowadays and is called small incision surgery and takes about half an hour. In a lot of cases it is done under local anesthesia.

Types of lens used

  • Mon focal- fixed lens for one level vision usually distant
  • Multifocal- may have two or more levels distant & near
  • Accommodating- very similar to natural human lens General healing time after the procedure is eight to ten weeks.

Most people experience vision improvement almost immediately after the cataract surgical procedure and start to perform daily chores. There may be a stitch needed due to the cut in the eye but it typically heals by itself. It is recommended that patients should avoid vigorous physical activities right after surgery.

Moreover, both eyes should not be operated at the same time as that can pose serious risks. After the procedure, a regular progress chart should be maintained to monitor the healing and after testing the vision, the appropriate glasses should be used. A healthy diet of fruit and leafy green vegetables and exercise can go a long way in preventing the disease.

source:  flickr/orbis_emea