Understanding Cataract Types and Their Treatment
Many people are surprised to learn that there isn’t just one type of cataract. Cataracts can develop in different parts of the eye’s natural lens, causing slightly different symptoms and affecting vision in different ways.
The good news is that cataract surgery is one of the safest and most successful procedures performed today. Regardless of the type of cataract you have, treatment involves removing the cloudy lens and replacing it with a clear artificial lens known as an intraocular lens (IOL).
Understanding the different types of cataracts and the available surgical techniques can help you feel more confident about your treatment options and what to expect.
What are Cataracts?
A cataract occurs due to a build-up of cells in the eye’s natural lens, changes in lens cell growth patterns, changes in cell proteins, or a combination of these. The pattern of changes determines the type of cataract that develops.
All cataract types are treated the same way, which is a fast and painless procedure to remove the cataract and replace it with a clear lens implant, or intraocular lens (IOL). There are different types of lenses that can provide clear vision without glasses at various distances.
Most Common Types of Cataract
The different types of cataracts share many similarities in terms of the symptoms patients experience, but there are some differences in symptoms as well as the speed at which the cataract can develop and the rapidity of the decline in vision. It is of vital importance to understand the type of your cataract and treat it accordingly.
Nuclear cataract and nuclear sclerotic cataract
The main body of the eye’s natural lens is called the nucleus. When cells build up in this central part of the lens, the lens gradually becomes yellow and cloudy, resulting in what is known as a nuclear cataract or nuclear sclerotic cataract.
Common symptoms of a nuclear cataract include:
- Gradually worsening distance vision
- Difficulty reading road signs
- Reduced contrast sensitivity (needing brighter lights to see)
- Colours appearing more yellow or faded
- Increasing reliance on brighter lighting
A nuclear cataract is the most common type of age-related cataract and typically develops slowly over a period of years.
Since vision changes gradually, many people adapt to the decline without fully realising how much their sight has deteriorated and only consider cataract surgery after an optician advises that their vision no longer meets the legal standard for driving.
Cortical cataract
A cortical cataract develops in the outer layer (cortex) of the eye’s natural lens. It appears as white, opaque lines that extend towards the centre of the lens, often resembling the spokes of a wheel.
Compared with nuclear cataracts, cortical and posterior subcapsular cataracts can progress more quickly and frequently cause problems with glare and bright lights.
Common symptoms of a cortical cataract include:
- Increased sensitivity to sunlight
- Glare from headlights
- Difficulty driving at night
- Blurred or fluctuating vision
- Halos around lights
Less Common Types of Cataract
Posterior capsular cataract
A plaque of cells on the back surface of the eye’s natural lens. As well as a decline in vision this type of cataract often produces sensitivity to light such as glare and starburst.
A Posterior subcapsular cataract usually develops more rapidly than nuclear cataract leading to a faster decline in vision and increasing sensitivity to light, over months rather than years.
Congenital cataracts
Cataract that is present at birth.
Christmas tree cataract
Probably the ‘prettiest’ type of cataract, the Christmas tree cataract has a multicoloured sparkly appearance in the lens. The change is caused by an accelerated breakdown of membrane-associated denatured proteins induced by elevated calcium levels.
Diabetic cataract
Diabetes is associated with early development of cataract. If left untreated high blood sugar can slowly damage blood vessels throughout the body (including the tiny blood vessels in the eyes).
Bilateral cataracts
Cataract usually occurs in both eyes (bilateral). It is unusual for a cataract to occur in only one eye (unilateral) without any sign of cataract in the other eye. It is possible, however, to have bilateral cataract but for the cataract of one eye to be more advanced that the other and leading to worse vision on that side.
Sometimes, patients with bilateral cataract report being troubled by the vision in only one eye. Then, after having that cataract removed and regaining excellent vision, they notice the poor vision in the eye they thought was still seeing well and request the same operation for the second eye.
Blue dot cataract
Blue dot cataract is exactly that: many round, blue opacities seen throughout the body of the lens and causing the usual symptoms of cataract.
Snowflake cataract
An uncommon cataract made of small white opacities within the lens, giving the appearance of snowflakes. It is associated with diabetes but can occur in non-diabetics also.
What Are the 3 Types of Cataract Surgery?
Although cataracts can develop in different parts of the lens, the goal of treatment is always the same: to remove the cloudy lens and replace it with a clear artificial lens.
The three main types of cataract surgery are:
Phacoemulsification
Phacoemulsification is the most commonly performed form of cataract surgery in the UK.
During the procedure, ultrasound energy is used to break the cloudy lens into tiny fragments, which are then gently removed through a small incision. A clear artificial lens is then inserted to restore vision.
This technique is suitable for the vast majority of cataracts, including nuclear and cortical cataracts, and is associated with excellent visual outcomes and a relatively quick recovery.
FLACS (Femtosecond Laser-Assisted Cataract Surgery)
Femtosecond Laser-Assisted Cataract Surgery (FLACS) uses advanced laser technology to perform certain stages of cataract surgery with a high degree of precision.
The laser can be used to create surgical incisions and soften the cataract before it is removed. This has been available for over 15 years but has not been shown to reduce complications or offer better results than established phacoemulsification.
FLACS may be suitable for some patients depending on their eye health and individual requirements.
Extracapsular Cataract Extraction
Extracapsular cataract extraction is a more traditional cataract surgery technique.
Rather than breaking the cataract into small fragments, the cloudy lens is removed in a larger piece through a wider incision. The approach is generally reserved for particularly dense or advanced cataracts that may not be suitable for standard phacoemulsification techniques.
Today, it is used far less frequently than modern small-incision cataract surgery.
Does the Type of Cataract Affect Treatment?
While different cataract types can cause different symptoms and may progress at different rates, the treatment approach is largely the same.
During a consultation, your surgeon will assess the type, location and density of the cataract, as well as the effect it is having on your vision. This allows them to recommend the most appropriate treatment plan for your individual needs.
Whether you have a nuclear cataract, cortical cataract, or another form of cataract, modern cataract surgery can safely and effectively restore clearer vision and help you return to the activities you enjoy.
Vision Outcomes
The most important determinants of good vision after cataract surgery include:
- the surgical safety record of the surgeon (posterior capsule rupture rate);
- the incision size and location (micro-incision surgery induces less astigmatism than larger incisions);
- planning ahead that includes consideration of how surgery will change the shape of the cornea (surgically induced astigmatism) – without this the patient is almost certain to have astigmatism after surgery and need glasses to see properly;
- taking accurate measurements of the eye before surgery and using the most accurate mathematical calculations to select the strength of lens implant for each individual eye. Note: there are many ways to measure the eye and even more methods to calculate for the lens implant, and they are NOT all the same;
- ensuring that contact lenses are removed for the appropriate period of time before measurement are taken to reduce the chance of inaccurate results;
- using specialised measurements and mathematical formulae for eyes that had previous refractive surgery such as LASIK or Radial Keratotomy – such eyes are much more likely to suffer inaccuracies in the post-operative result but the risk can be minimised with use of specialist methods;
- surgical techniques that minimise the duration of surgery and energy used in the eye to break up the natural lens or cataract
Concerned About Changes to Your Vision?
At iLase, our experienced consultant, Prof Mohammed Muhtaseb, uses advanced diagnostic technology to identify the type and severity of your cataract and discuss the most appropriate treatment options for your individual needs.
Whether you have a nuclear cataract, cortical cataract or another form of cataract, we’re here to provide clear advice and expert care every step of the way.
Book a consultation today to find out how cataract treatment could help restore clearer vision and improve your quality of life.
