Cataract Surgery
Cataract surgery removes the cloudy natural lens from the eye and replaces it with a clear artificial lens called an intraocular lens. The goal is to improve sight that has been affected by the cataract. Surgery may be considered when vision changes interfere with daily activities such as reading, driving or working. The timing and suitability of surgery depend on an individual assessment by an ophthalmologist. For symptoms, causes and diagnosis, read the Cataracts condition guide.
Key Takeaways
• The cloudy natural lens is removed and replaced with an artificial lens.
• Surgery may be discussed when cataract-related vision changes affect activities that matter to you.
• Eye measurements taken before surgery help calculate the power of the replacement lens.
• The operation is performed as a day procedure in many cases, using local anaesthesia.
• Improvement varies between patients. Other eye conditions may limit the result, and some people continue to need glasses.
Quick Facts |
Treatment type Eye surgery |
Provided by Ophthalmologist |
Setting Day surgery for many routine cases; arrangements vary |
Anaesthesia Anaesthetic eye drops or injection; sedation in selected cases |
Hospital stay Overnight admission is not required for many routine cases |
Recovery Progressive; early visual improvement and complete healing are separate milestones |
May be considered for People whose cataracts affect vision, daily activities or quality of life |
Reading time About 9 minutes |
What Is Cataract Surgery?
Cataract surgery is an operation to remove the eye's cloudy natural lens and replace it with a clear artificial lens. The artificial lens, called an intraocular lens, takes over the focusing function of the natural lens. The artificial lens usually remains in the eye long term and does not normally need to be replaced.
Once the natural lens has been removed, the original cataract cannot grow back.
What Is Cataract Surgery Used For?
Cataract surgery is used to treat cataracts that are affecting vision and daily life. It may also be considered when a cataract prevents adequate examination or treatment of another eye condition. Surgery is the only treatment that removes a cataract.
Who May Be Considered for Cataract Surgery?
Surgery may be discussed when cataract-related vision changes affect important activities such as reading, driving, working, recognising faces or maintaining independence. The decision is based on several factors:
• How the cataract affects your daily life
• What the eye examination shows
• Whether other eye conditions are present
• Your medical history
• The likely benefits and risks in your situation
• Your own preferences
Surgery is not automatically needed as soon as a cataract is found. Some people manage well for a considerable time before surgery becomes a practical consideration. Where another health or eye issue is present, it may require further assessment or planning before surgery rather than being an absolute barrier.
How Does Cataract Surgery Work?
The most widely used technique is called phacoemulsification. During this procedure, ultrasound energy is used to break the cloudy lens into small fragments, which are gently removed from the eye. A clear artificial intraocular lens is then positioned within the remaining lens capsule.
What Should You Discuss Before Surgery?
• The goal of surgery and what improvement is realistic in your case
• Whether other eye conditions may affect the result
• Your current medicines, including blood-thinning medication, eye drops, supplements and over-the-counter products
• Any previous eye surgery
• How anaesthesia will be managed
• Which type of replacement lens may suit your situation
• Practical arrangements: transport home, time off work, help at home
• Costs, fees and financing options
For financial planning, read how MediSave and insurance may apply to cataract surgery in Singapore. When published, the Cataract Surgery Costs in Singapore guide will explain what may be included in a surgical bill.
How Is the Replacement Lens Planned?
Before surgery, precise measurements of the eye are taken using a process called biometry. These measurements help calculate the power of the artificial lens.
The choice of lens depends on your eye health, measurements, visual priorities and the trade-offs you are comfortable with. Broad categories include:
• Monofocal lenses, which focus at one set distance
• Toric lenses, which can correct astigmatism
• Multifocal lenses, which aim to provide focus at more than one distance
• Extended-depth-of-focus lenses, which aim to provide a continuous range of focus
Lens options may involve trade-offs relating to range of focus, the likelihood of needing glasses, glare or haloes in certain lighting, contrast and suitability where other eye conditions are present. Your ophthalmologist will discuss which lens may suit your situation. Some people still need glasses for certain distances or activities after surgery, regardless of the lens type chosen.
How Should You Prepare for Cataract Surgery?
Your surgical team will give you specific instructions. These may cover eating and drinking before the day of surgery, eye drops to use in advance and any adjustments to your usual medicines. Instructions vary between institutions and patients, so follow the guidance given to you rather than relying on general advice.
Do not stop or change prescribed medication unless your treating clinician or surgical team advises you to do so.
Before the day of surgery, you should also:
• Arrange transport to and from the surgical centre, as you will not be able to drive yourself home
• Plan time off work if needed and arrange help at home for the first day or two
• Bring your current spectacles and any documents requested by the clinic
• Prepare any remaining questions for the surgical team
What Happens During Cataract Surgery?
1. The eye is prepared and anaesthesia is given, with drops or an injection around the eye.
2. A small opening is made in the outer layer of the eye.
3. The cloudy lens is broken up using ultrasound (phacoemulsification) and the fragments are removed.
4. A clear artificial intraocular lens is positioned within the remaining lens capsule.
5. The patient is monitored before being discharged.
Many patients remain awake during the procedure. You may notice light or movement, but anaesthesia is used to reduce discomfort, although individual experiences vary. Some patients may also receive sedation. The operation itself may be relatively brief, but total time at the surgical centre is longer because it includes preparation and monitoring.
Cataract surgery may be arranged on separate dates for each eye. Selected patients may be offered surgery to both eyes during one session, depending on clinical assessment and the practices of the surgical centre.
What Happens After Cataract Surgery?
You will be given eye drops to help prevent infection and reduce inflammation. An eye shield may be recommended, particularly when sleeping. Avoid rubbing the eye.
Some people experience temporary effects in the early days after surgery, described in the section below. These differ from complications, which are also covered separately.
Some people notice an improvement in vision within a few days, while for others the improvement develops over a longer period. Early visual improvement and complete healing are different milestones. Your surgical team will advise when it is safe to resume driving, exercise, swimming, work and other activities. Follow their instructions rather than relying on general guidance.
Attend all follow-up appointments. These allow the team to check healing, monitor eye pressure, review your eye drops and plan a new spectacle prescription once the eye has stabilised.
What Are the Potential Benefits and Limitations?
The main goal is to improve sight that has been affected by the cataract. When surgery is appropriate for the individual patient, possible improvements may include clearer vision for reading, driving and work, reduced glare and greater ease with everyday tasks.
However, the result depends on individual factors. Other eye conditions, such as macular degeneration or diabetic retinopathy, may limit the degree of improvement. Some people continue to need glasses for certain distances or activities. Surgery does not treat unrelated retinal, optic-nerve or other eye disease, and further treatment may occasionally be needed.
What Are the Expected Effects and Possible Complications?
Expected temporary effects
Some people experience temporary effects in the days after surgery, which may include:
• Mild discomfort or a gritty sensation
• Watering or increased tearing
• Sensitivity to light
• Temporary blurring
These effects differ from complications and should settle as the eye heals.
Possible complications
Complications can occur, although the likelihood and severity vary. Your ophthalmologist will discuss those most relevant to your situation. They may include:
• Infection or inflammation inside the eye
• A temporary or sustained increase in eye pressure
• Swelling of the cornea or retina
• Retinal detachment
• Problems with the position of the artificial lens
• Capsule complications during surgery
• Persistent visual symptoms such as glare or haloes
• A need for additional treatment
Posterior capsule opacification
After surgery, the capsule behind the artificial lens may gradually become cloudy. This is called posterior capsule opacification and is sometimes referred to as a "secondary cataract". It is not the original cataract returning. It can be treated with a brief laser procedure called YAG laser capsulotomy.
When Should You Seek Urgent Medical Advice?
Contact your surgical team promptly if you experience: • New or worsening loss of sight • Severe or persistent eye pain • Marked redness that increases rather than improves • New flashes of light or a sudden increase in floaters • Any symptom your surgical team has identified as requiring urgent contact |
Do not wait for your next scheduled appointment if any of these occur.
What Are the Alternatives?
Surgery is the only way to remove a cataract. When symptoms are manageable, temporary measures may include:
• An updated spectacle prescription
• Brighter lighting for reading and close work
• Magnification aids
• Anti-glare sunglasses
• Continued observation with periodic eye examinations
These measures may help manage visual difficulties for a time, but they do not remove the cataract or stop it from progressing.
What May Happen If Surgery Is Delayed?
Some people manage mild cataracts comfortably for a considerable period. However, vision may worsen gradually, and activities such as reading, driving and working may become more difficult over time.
An advanced cataract may also make it harder for an ophthalmologist to examine the back of the eye. Cataract surgery may still be considered when a cataract is advanced, although the expected result depends on the health of the rest of the eye and the person's individual circumstances.
The timing of surgery is a decision to discuss with your ophthalmologist.
Questions to Discuss With Your Ophthalmologist
• What is the goal of surgery in my case?
• How might my other eye conditions affect the result?
• What type of replacement lens may be suitable for me?
• Will I probably still need glasses afterwards?
• What are the main risks in my situation?
• What preparation is required?
• When may I return to work, driving and exercise?
• What symptoms should prompt an urgent call?
• What happens if I choose to wait?
• Which fees, lens charges and follow-up costs should I ask about?
Your Possible Care Journey
1. Cataracts detected during an eye examination
2. Assessment of how the cataract affects daily life
3. Discussion of surgery, alternatives and timing
4. Eye measurements and preoperative preparation
5. Surgery day
6. Early recovery, eye drops and follow-up appointments
7. Spectacle prescription updated once the eye has stabilised
Cataract assessment and surgery are available through public and private healthcare providers in Singapore. Referral, appointment and subsidy arrangements vary, so patients should check the requirements of the relevant provider and financing scheme.
Find an ophthalmologist or eye clinic for an assessment.
Frequently Asked Questions
Is cataract surgery painful?
Anaesthesia is used to reduce discomfort. Most patients feel pressure or awareness of light rather than sharp pain during the procedure. Individual experiences vary. Some mild discomfort or a gritty feeling may occur in the days after surgery and should settle as the eye heals.
Will I be awake during cataract surgery?
Many people remain awake. The eye is numbed with drops or an injection, and some patients may receive sedation. General anaesthesia may be considered in selected cases.
Will I still need glasses after surgery?
Possibly. Whether you need glasses depends on the type of lens implanted, the measurements of your eye and the eventual result. Your ophthalmologist will discuss realistic expectations before the procedure.
How should I prepare for cataract surgery?
Your surgical team will provide specific instructions about eating, drinking, eye drops and medicines before the day of surgery. Do not stop or change prescribed medication unless advised. Arrange transport home, as you will not be able to drive.
When may I drive after cataract surgery?
Your surgical team will advise when it is safe to resume driving. This depends on how well you can see after surgery and the legal requirements for driving vision. Do not drive until you have been told it is safe to do so.
Can both eyes be done at the same time?
Cataract surgery may be arranged on separate dates for each eye. Selected patients may be offered surgery to both eyes during one session, depending on clinical assessment and the practices of the surgical centre.
Can a cataract come back after surgery?
The original cataract cannot return once the natural lens has been removed. However, the capsule behind the artificial lens may become cloudy over time, a condition called posterior capsule opacification. This can be treated with a brief laser procedure.
References
Singapore clinical sources
• Singapore National Eye Centre. Cataract Surgery. https://www.snec.com.sg/patient-care/conditions-treatments/cataract. Accessed 14 July 2026.
• Singapore National Eye Centre. Cataract and Comprehensive Ophthalmology: What We Do. https://www.snec.com.sg/our-specialties/clinical-interests/cataract-comprehensive/what-we-do. Accessed 14 July 2026.
International clinical guidance
• National Eye Institute. Cataracts. Updated 26 November 2025.
• National Eye Institute. Types of Cataract. Updated 6 August 2025.
• National Institute for Health and Care Excellence. Cataracts in Adults: Management, NG77. Published 26 October 2017; last reviewed 20 May 2025.
Urgent-warning-sign references
• National Eye Institute. Retinal Detachment. Updated 5 November 2025.
• National Eye Institute. Types of Glaucoma. Updated 5 December 2024.