What are Cataracts
Cataract is a clouding of the eye’s lens. When we look at something, light rays travel into our eye through the pupil and are focused through the lens onto the retina, a layer of light-sensitive cells at the back of the eye. The lens must be clear in order to focus light properly onto the retina. If the lens has become cloudy, this is called a cataract.
Removal of a cataract is one of the most common surgical procedures performed in Australia. It has a high rate of success due to the modern methods used.
If the rest of the eye is healthy, the likelihood is that cataract surgery will restore good vision. If there is macular degeneration, glaucoma or diabetes, final vision may be limited by these conditions.
Of every 100 operations to remove a cataract, 99 will result in improved vision. Despite the benefits of modern cataract surgery, there are risks. These will be discussed later.
Causes and symptoms
Cataracts develop as a normal part of the ageing process. By the age of 60, about half of all adults will have some cataract formation.
The earliest symptoms can begin with glare and sensitivity to bright light. Later, as the cataract continues to worsen, haloes may appear around lights. Haloes are especially noticeable when driving at night, and at the same time, night vision typically decreases. Vision becomes more blurred, hazy and foggy. Colours often become duller or darker. The power of the eye changes, with the becoming more short-sighted. As a result, some patients find that their reading glasses are not needed, although the clarity of the vision is diminished.
Removal of a cataract may be necessary when vision has worsened or if daily activities, such as reading, driving and hobbies are affected, or if personal safety is at risk. If vision is unaffected or only slightly affected by a cataract, no treatment is necessary.
Cataracts cannot be cured by any type of medication, eye exercise, alternative therapy, diet or glasses. Surgery is the only way to treat a cataract.
Possible complications of cataract surgery
Any surgical procedure is associated with risks to the patient. While Dr. Yohendran will make every attempt to minimise risks, complications can occur.
Serious complications following cataract surgery are not common because of the significant surgical advances in recent years. Based on Dr Yohendran’s personal data, 99% of cataract surgery cases are uncomplicated. The 1% chance of complications includes:
- Infection inside the eye
- Bleeding and blood collection within the eye
- Excessive inflammation
- High pressure within the eye
- Retained piece of cataract in the eye
- Damage to, or dislocation of, the artificial lens
- Detachment of the retina
- Drooping eyelid
- Swelling and clouding of the cornea
- Extremely rarely, blindness and loss of operated eye.
- Extremely rarely, the unoperated eye may become inflamed, with loss of vision (“sympathetic ophthalmia”).
Although most complications resolve over time, or are treated with further surgery, they can affect vision, sometimes permanently.It is important to realise that although complications can occur, like in any medical procedure, they are extremely rare in Dr Yohendran’s hands.
Intraocular lens implant
After you have decided to have cataract surgery, your eye will need to measured to determine the optical power of the artificial lens. The measurements will be performed by trained technicians using state-of-the art equipment. This is not painful.
The focus of the lens implant is fixed and cannot change. The lens implant is usually chosen for distance vision. In these cases glasses are required for reading. Alternatively, the lens power may be intended for reading, or a multifocal lens may be used.
There are many issues to consider when choosing the type of lens implant, and if you have a particular preference, this should be discussed with Dr Yohendran and his staff.
Of course, perfect vision without the need for glasses is everybody’s wish, but unfortunately, this is not possible. The lens implants do not move inside the eye, and hence their focus is fixed. Many patients are not dependant on glasses after cataract surgery, but for certain visual tasks, that require very refined vision, glasses help. Such tasks include driving at night, reading in bed with low ambient light, and reading very small print.
Cataract removal is usually performed under local anaesthetic and light sedation. A specialist anaesthetist gives the anaesthetic and sedative. Cataract surgery is performed as a day-only procedure.
Modern anaesthetic drugs are safe with a few risks. However, a few people may have a serious reaction to an anaesthetic drug. Tell your anaesthetist and Dr. Yohendran if you have had a previous anaesthetic reaction.
Surgical techniques for removal of cataracts
The most common surgical technique is Phacoemulsification. This involves removing the natural lens and replacing it with an artificial lens. Viewing the eye through a high-powered microscope placed above the patient, Dr Yohendran will make a tiny incision at the junction where the cornea meets the sclera. A small probe is inserted to divide the cloudy lens into small pieces. The pieces are gently suctioned away. The artificial lens is inserted and held in place by the lens capsule. The artificial lens is also called an “intraocular lens implant”. It is a transparent, artificial disc with a shape similar to the natural lens. The incision is so small that it usually requires no stitches. After surgery, the eye is covered with a pad and shield for protection. The operation usually takes approximately 20 minutes. The hospital stay is usually 3 hours.
Laser-assisted Cataract Surgery
Since 2012, some parts of the cataract surgery have been performed with a laser (femtosecond laser). This laser is used to automate some parts of the surgery that are performed manually. Dr Yohendran can program the laser to create the opening to the lens capsule, and soften the cataract. Phacoemulsification and intraocular lens implantation follow, as per the description above.
The potential advantages of laser-assisted cataract surgery are yet to be proven, so at this stage they are debatable. The surgery may be more predictable, but whether this translates into better visual outcomes is being studied, with early experience being equivocal.
Cataract surgery on the second eye
If both lenses are affected by cataracts, Dr Yohendran will wait until the first eye has healed before operating on your second eye. This is usually 2 weeks.
Recovery from cataract surgery
After surgery, you will be moved to a quiet area to recover from the effects of the sedation and local anaesthesia, which are slight. You will be offered a drink and small snack.
Most patients are ready to leave within an hour or so. Arrange for someone to drive you home. Alternatively, Chatswood Private Hospital can arrange courtesy transport, or an overnight stay.
It is best to have someone help you for a day or so as you recover from the surgery.
Most patients do not have post-operative pain. Some discomfort is normal. Usually using over-the-counter medicines such as paracetamol are all that is needed, if that.
A review appointment will be made with our clinic within 24 hours of the surgery, and then 1-2 weeks later.