There are many possible kinds of cataracts. Below are some of the common ones you should know.
Nuclear Cataracts
Causes and risk factors: Typically caused by ageing, but risk factors include smoking, alcohol consumption, and prolonged exposure to sunlight.
Nuclear cataracts are arguably the most common of all cataracts. They take their name from the fact that they chiefly affect the centre of the eye’s lens, also known as the nucleus.
The strangest thing about nuclear cataracts is that they may sometimes cause a temporary improvement in vision, specifically near vision. This is because the hardening of the lens that leads to nuclear cataracts can temporarily cause the lens to be more refractive.
Over time, however, this progresses to the typical cataract symptoms: blurry vision, muddy colours, and poor night vision.
Cortical Cataracts
Causes and risk factors: Also associated with ageing, with typical contributing factors including diabetes, exposure to UV light, and regular use of medications like corticosteroids.
Cortical cataracts form in the lens cortex, i.e. the area surrounding the centre or nucleus of the eye’s lens.
Most of them show up as white opacities that look like wedges starting at the edge of the lens. These wedges progress towards the centre and look like wheel spokes.
These cortical cataracts are interesting in that they progress very differently between people. Some individuals with cortical cataracts see rapid progression while others see the opposite.
Posterior Subcapsular Cataracts
Causes and risk factors: Generally linked to prolonged use of steroid medications, with diabetes and extreme nearsightedness as risk factors.
These get their name from the fact that they occur at the rear part of the lens. They can often be found directly in the path of the light that is supposed to enter the eye for clear vision.
As a result, posterior subcapsular cataracts can cause serious glare or halos around lights. They also tend to be associated with quick degeneration of reading vision. Furthermore, they are among the fastest-progressing types of cataracts.
Congenital Cataracts
Causes and risk factors: Genetic factors seem to have a big role in their development, as do maternal infections in pregnancy (such as rubella).
Congenital cataracts are present at birth or may develop during a person’s infancy. They also vary in severity and cause, with some being hereditary and others being the outcome of infections.
While more research needs to be performed on these, we have noted that certain conditions seem to be linked to their development. These conditions include rubella, galactosemia, and some genetic disorders.
Traumatic Cataracts
Causes and risk factors: Related to eye injuries, whether blunt or penetrating.
Any serious eye injury can lead to a traumatic cataract. This is because injuries to the eye can cause the proteins in the lens to clump together or degrade, leading to the cloudiness associated with cataracts. Note that there can be a delay between the actual trauma and the development of a cataract. It can be as short as days, or as long as months (or more).
Secondary Cataracts
Causes and risk factors: Underlying health conditions as well as long-term medication use.
These cataracts are essentially complications of other conditions or side effects of medication.
The most commonly associated conditions with these cataracts are glaucoma and diabetes. As for medications, steroid medications are often suggested as possible causes.
Radiation Cataracts
Causes and risk factors: Exposure to ionising radiation, perhaps through accidents or even radiation therapy for cancer.
These cataracts can develop following exposure to some kinds of radiation. This includes the radiation used to treat cancer patients, so it is fairly often associated with them.
These are among the cataracts that develop at the back of the eye’s lens. Moreover, they can have highly delayed development, which means they only show up years after exposure in some cases.
Cataracts are caused by a clumping-together of the proteins in the lens of your eye.
For most people, this is a natural outcome of ageing. Proteins like the ones in our eyes tend to break down over time. At around 40, they do so enough to form clumps.
These clumps create small clouds in the otherwise-clear lens in your eye. Just like impurities in clear glass, they obstruct the flow of light and thus impede vision.
While cataracts can be a natural consequence of ageing, certain factors can predispose people to develop them earlier, or to be more likely to get them. Below is a list of known risk factors for cataract development:
The symptoms of cataracts include gradual blurring of vision and reduced perception of colour. This is a natural outcome of the cloudy parts of the eye reducing visual clarity.
The severity of symptoms is generally dependent on the progression of the disease. In the early stages, cataracts are usually barely noticeable. Over time, the clouding in the lens worsens. That leads to worsened symptoms and a higher chance of detection.
Below are some of the symptoms reported for cataracts:
Cataracts are diagnosed by an eye doctor using a slit lamp microscope. A comprehensive eye check is also performed. This is to exclude other abnormalities of the eye from the diagnosis.
Here are the most common tests used for cataract diagnosis:
Cataract surgery is a procedure where the clouded lens of a patient’s eye is removed and replaced with an artificial one. This is done to restore clear vision to the patient.
Types of Surgical Methods for Cataract Surgery
There are two main methods used in cataract surgery: traditional phacoemulsification and laser-assisted surgery.
Expected Recovery Time and Success Rates
Cataract surgery boasts a fairly high success rate.
97-98% of patients are said to experience improved vision following it.
Recovery time is similarly good, with many patients reporting that they saw improvements within a few days. However, recovery time always varies for patients. Full recovery also takes longer, with some taking as little as 4 weeks and others requiring around 8 weeks.
Risks and Side Effects
Cataract surgery is generally considered a safe surgery. That said, it has risks like every other medical procedure.
Potential complications of this procedure include infection, bleeding, retinal detachment, and heightened intraocular pressure (pressure in the eye).
Some people also note a clouding of the lens capsule after surgery. This is called posterior capsule opacification. Fortunately, this can be solved with a laser procedure.
Preparation, Expectations, and Post-Surgery Recovery
Before surgery, your doctor will conduct an eye examination and discuss the procedure with you. At this time, be sure to ask all of the questions you wish about the procedure, the recovery process, as well as any precautions you should take after the surgery.
On the day of the surgery, you can expect to receive local anaesthesia. This will be followed by the surgery itself.
After the surgery, you may have mild discomfort and slightly blurry vision. It should improve over time as your eye heals. Your doctor will also provide a list of recovery notes, such as advice to avoid strenuous activities during recovery.
Cataract Surgery Fees
Fees for cataract surgery vary depending on a few conditions.
In Singapore, the price can range from just over $1,000 to $5,000 per eye in a public hospital. The lower end of the range is for subsidised procedures and the higher end is for those getting the surgery without subsidies.
The prices often go up for private eye clinics. You may pay anywhere from $5,000 to $12,000 per eye in these clinics, depending on factors like the IOL selected and the surgeon’s reputation.
Cataract surgery is MediSave claimable. You can use your MediSave to pay a portion of the fees for cataract surgery. For surgery or admissions, MediSave claims will be processed by the admitting hospital. You can also use your MediSave for yourself or your immediate family members which include your spouse, children, parents and grandparents.
