The Three Types Of Cataracts And Their Treatments
What is a cataract?
A cataract refers to the build-up of protein tissue in the eye’s lens leading to cloudiness and opacity. The cloudiness and opacity limit the light reaching the retina leading to blurry and faded vision. Cataracts are the leading cause of vision loss and naturally occur as we age.
This article will cover the three types of cataracts, their symptoms, treatment, and prevention.
What are the main types of cataracts?
Cataracts that form at the back of the lens (posterior subcapsular cataracts)
These are cataracts that develop at the back of the lens (‘posterior’), inside the capsule (‘subcapsular) that holds the lens in position. The changes in the lens make light get more focused towards the rear of the lens, causing different symptoms.
Symptoms of the posterior sub-capsular cataracts are:
- Difficulty or inability to see in areas with a large bright light source due to pupillary constriction and accommodation.
- Reduced night vision
- Glare or halos, especially in low light situations such as driving at night
- Blurry vision that may cause reading difficulties due to light passing through the cataract to enter the eye when the pupil is constricted
The most common cause of Posterior sub-capsular cataracts (PSC) is usually natural aging. However, eye trauma (injury to the eye), exposure to ionizing radiation, inflammation, corticosteroid usage, and excessive alcohol consumption has also been linked to PSC.
Compared to the other types (nuclear or cortical cataracts), PSC typically occurs in younger people. Progression of PSC is typically faster than the other types of cataracts. In most people, it is typically visually significant in a few months to years; however, in rare cases, it can progress quickly in weeks or even days.
Cataracts forming at the center of the lens (nuclear cataracts)
‘Nuclear cataracts’ or ‘nuclear sclerotic cataracts’ develop at the center of the lens (hence ‘nuclear’) and involve hardening of the tissue (‘sclerosis’). Though it starts at the center of the eyes, it can progress and cover other layers of the eye. It is the most common type of cataract caused by the lens’s natural hardening and yellowing due to aging. Over time, new fibers forming at the eyes’ edge push the aging tissue towards the center, forming dense tissue.
Symptoms of Nuclear sclerotic cataracts are:
- Reduce ability to focus on objects due to lens hardening (Nuclear sclerosis)
- Double vision
- Fading or yellowing of colors leading to difficulty distinguishing colors
- Reduced distant vision due to lens hardening
- Difficulty reading due to blurred vision and difficulty distinguishing colors
- Glare and halos, especially in an area with bright sources of light.
The most common cause of these cataracts is usually age or age-related changes to the human eye. The protein in the lens is typically clear, allowing light to pass through when we are younger. However, with age, the proteins break down, forming yellow-colored tissue.
It is typically more common in older individuals. However, people with diabetes, near-sightedness or short-sightedness myopia, brown eyes, and women are more likely to develop nuclear sclerosis cataracts. They progress slowly over long periods, with symptoms appearing after a few years.
Cataracts forming at the edges of the lens (cortical cataracts)
These are cataracts that start from the edges or outer layer (‘cortical’= outer layer). They start opposite the nuclear sclerotic cataracts, on the outer edge of the lens. During the progression of cortical cataracts, they form white spoke lines from the outer edge towards the center of the lens, causing abnormal light scattering in the eye.
- Blurry vision
- Reduce vision starting from the edges and moving toward the center of the vision
- Hazy or opaque objects beginning from the outer edges
- Poor depth perception
- Glare and light sensitivity
The most common causes of Cortical Cataracts are trauma or injury, gaining weight, and a history of cataracts in the family. Inflammation, exposure to ionizing radiation, trauma history, and eye surgery have also been linked with increased risks.
Progression is usually quick, with symptoms commonly appearing within months rather than years like in Nuclear sclerotic cataracts. Lifestyle risk factors associated with increased incidence are chronic smoking, excess alcohol consumption, and obesity.
Treatment of cataracts
All cataracts are treated using cataract surgery, which is done by an ophthalmologist. Cataract surgery involves removing and replacing the affected clouded lens with a clear artificial intraocular lens. The surgery is typically done outpatient and is relatively quick and painless.
Recovery typically takes a few days to weeks after surgery with minimal risks of complications, especially if the post-operation procedures are followed. Possible complications are eye infection, retina swelling, retinal detachment, blurred vision, pain, and glare. In extremely rare cases, vision loss.
Cataract surgery does not correct or restore vision problems from other eye conditions such as glaucoma, diabetic retinopathy, or normal aging. Individuals with previous cataracts can also develop cataracts again, usually referred to as Secondary Cataracts. Secondary cataracts are treated by cutting a small hole through the capsule to allow light through to the retina.
Prevention of cataracts
You can reduce the risk of developing cataracts through lifestyle changes. Changes are:
- Smoking cessation
- Eating healthy diets with antioxidants
- Proper management diabetes of diabetes through exercising, proper diet, and care.
- Protecting the eyes from ionizing radiation from the sun or artificial sources of light such as tanning lights
- Regular eye examination
- Limiting steroidal use
There are three main types of cataracts categorized by the location where they start forming the back, center, or lens edges. Different cataracts can affect vision in slightly different ways. However, they can lead to blurred vision and eventually blindness if left untreated.
You can easily treat cataracts with outpatient surgery, regardless of the variations or symptoms. If you are experiencing abnormalities or vision loss, schedule an appointment with us for further guidance. Our ophthalmologists are ready to assist correct your vision allowing you to return to your normal lifestyle.