How is the eye measured?
Your eye is measured with the ZEISS IOLMaster 700 optical biometer and corneal mapping, and retinal imaging checks the macula. The lens power is calculated with latest-generation formulas and checked by an experienced team.
Cataract surgery
Cataract surgery replaces the cloudy natural lens with a clear artificial lens chosen for your eye. It is day surgery, one eye at a time, usually taking under thirty minutes in theatre with anaesthetic drops or gel and sedation if wanted.
The main steps of cataract surgery. The cloudy lens material is removed and an artificial lens is placed inside the retained capsule.
Enlarge diagramHow does modern cataract surgery work?
The cloudy lens is removed through a very small opening and replaced with a clear artificial lens that stays in the eye permanently.
The technique is called phacoemulsification. A fine probe uses ultrasound to break the cataract into tiny pieces, which are drawn out through the same opening. The new lens is folded, inserted and opened into the natural lens capsule. The incision is so small that it usually seals without stitches.
For the procedure, laser patterns and recovery, read our guide to YAG laser capsulotomy for capsule clouding.
If floaters appear after treatment for a cloudy capsule, read what to expect after YAG capsulotomy.
Cataract surgery is one of the most frequently performed operations in Australia. It is day surgery, one eye at a time, usually with a gap of a few weeks between eyes.
- Day surgery; home the same day
- Usually under thirty minutes in theatre
- Drops or gel anaesthetic, with sedation if wanted
- A permanent lens chosen for your eye
- One eye at a time
How is cataract surgery planned?
Prepare the eye’s surface
Dry eye can cause fluctuating vision and unreliable measurements. Treatment and repeat measurements may be needed before the lens plan is finalised.
For practical instructions and illustrations, read the guide to lid hygiene for blepharitis. Follow your surgeon’s instructions about when to use this routine around surgery.
Share your eye history
Tell us about contact lenses, previous LASIK or other laser vision correction, injuries and earlier eye surgery. Ask how long to leave contact lenses out before measurements; the interval depends on the lens type and your eye.
Agree on realistic goals
Discuss the activities you want to improve, the likely need for glasses and any limits imposed by the retina or cornea. Bring your medication list and follow your own instructions about medicines, fasting and transport.
How lens calculations are checked
Choosing the focus of your replacement lens →
Read When do I need cataract surgery? for help with the timing decision.
For one refractive full-range option, read about the RayOne Galaxy spiral lens. →
What technology is used during cataract surgery?
Dr Chen uses ZEISS CALLISTO eye digital guidance and the Alcon UNITY Vitreoretinal Cataract System (VCS) for cataract surgery in the day surgery upstairs from his clinic, with a femtosecond laser for selected patients.
Digital guidance. ZEISS CALLISTO eye recognises your eye and overlays your measurements in the operating microscope: where to make the incisions, the size and position of the capsule opening and, for a toric lens, the exact alignment. No ink marks are needed on the eye.
Cataract removal. The UNITY VCS is a state-of-the-art surgical system. It measures pressure and flow inside the eye continuously and adjusts in real time. It is designed to keep the eye stable and to protect the cornea throughout the operation.
Retinal back-up. Because the same system is used for retinal surgery, Dr Chen can usually manage an unexpected retinal problem during a cataract operation if one arises.
About the technology in Dr Chen’s practice
- Iris
- Cataract, seen through the pupil
- Capsule opening guide, 5.0 mm
- Toric lens axis, 20°
- Incision guide
What happens on the day of cataract surgery?
Arrive and prepare
Drops are given to enlarge the pupil. The team confirms the eye, the lens and your details.
Anaesthetic
Usually anaesthetic drops or gel, often with light sedation so you are relaxed and comfortable. An injection around the eye is used when it suits the eye or the person better.
The operation
Through a tiny incision, ultrasound gently breaks up the cloudy lens so it can be removed. A folded artificial lens is placed in the same position and unfolds. Most operations take less than half an hour.
Recovery area
A short rest with a drink before you go home with a protective shield and drops. Someone needs to take you home.
The first days
Vision often improves within a day or two and settles over the following weeks. A review confirms the eye is healing as expected.
The day surgery is on level 4, directly above Dr Chen’s clinic on level 3, so your assessment, operation and follow-up visits all happen in the same familiar building.
What anaesthetic is used for cataract surgery?
Most people have cataract surgery awake, comfortable and unaware of the detail.
Anaesthetic drops or gel numb the surface of the eye. Many people also have light sedation from an anaesthetist, so the experience is calm rather than clinical. For some eyes, or for people who would rather not be aware of the operation at all, an injection around the eye or deeper sedation is the better choice.
The approach is decided with you beforehand, based on the eye, your general health and how you feel about the procedure. It is not one size fits all.
- Drops or gel, with or without sedation
- An injection around the eye for a fully numb eye
- Deeper sedation when it suits the person
Which lens is put in during cataract surgery?
What are the parts of a lens implant?
The central optic is the clear part of the lens. The curved arms, called haptics, help support it inside the eye.
Compare lens designs and optional features. Surface details and tint are enhanced for illustration; actual lenses vary.
Compare lens types, rotate and explore optional features.
Monofocal
Sharp focus at one distance, usually far. Glasses for reading.
→Toric
Corrects astigmatism, and can be combined with other designs.
→Extended range and multifocal
Reduce dependence on glasses across distances, with trade-offs that suit some eyes and not others.
→There is no single best lens. The choice follows your eye, including the health of the retina, and what you want your vision to do day to day.
Explore the individual lens guides → · Astigmatism correction →
The explanation below describes this graphic. Drawing it requires JavaScript.
A general guide to what each design is intended to do, not a prediction for an individual eye. Glasses are often still helpful beyond the shaded range. Reading depends on the lens, the focusing target chosen, lighting and the health of the eye.
Can I have cataract surgery if I have other eye conditions?
Many people have more than one thing going on. The plan should account for all of it.
Epiretinal membrane, macular hole, macular degeneration, previous vitrectomy or retinal surgery, high myopia, glaucoma and earlier laser vision correction all change the cataract conversation. They can affect the lens choice, the timing, the technique and what to expect afterwards.
Because Dr Chen operates on both the cataract and the retina, these situations are planned as one problem rather than handed between specialists. Where appropriate, a retinal procedure and cataract surgery can be considered together.
When a cataract and a retinal condition occur together, a retinal acuity meter can estimate how well the retina could see once the cataract is removed. This helps set realistic expectations before surgery.
IOL exchange and complex cataract
Which eye conditions need extra planning?
- Epiretinal membrane or macular hole
- Macular degeneration
- Previous vitrectomy or retinal surgery
- High short-sightedness
- Previous LASIK or other laser vision correction
What is recovery like after cataract surgery?
Most people are back to their usual activities within a few days, with drops for a few weeks.
- Use the drops as prescribed; they settle the eye and prevent infection.
- Avoid rubbing the eye, swimming and dusty environments for the period advised.
- Reading, screens and gentle walking are fine straight away.
- Driving can resume once vision meets the standard, usually after the first review.
- Glasses, if needed, are updated once both eyes have settled.
What are the risks of cataract surgery?
Cataract surgery is a common operation and most people do very well. As with any operation, complications can occur, from minor irritation to rare sight-threatening problems. These are discussed with you before surgery, together with the reasons they are uncommon and how they are managed if they arise.
An uncommon complication is part of the cataract falling into the back of the eye during surgery. This is usually treated by a retinal surgeon. Dr Chen is also a retinal surgeon, and he has written guidance for other eye surgeons on managing it.
Read Dr Chen’s articleHow can I make recovery easier?
Prepare support at home
Arrange someone to take you home and follow the hospital’s advice about having support afterwards. If drops are difficult, ask the team to demonstrate the technique and plan who can help. Keep your instructions and contact number easy to find.
Let comfort guide light activities
Reading, television and screens can usually be resumed as comfort allows. Vision may fluctuate while the eye settles. Use prescribed drops, avoid rubbing the eye, and follow your instructions about the shield, washing and activity restrictions.
Plan work, exercise and travel
Office work and a dusty or physical job have different demands. Ask for advice specific to your work, swimming, sport and travel plans. Driving requires adequate vision and the advice of your treating team, rather than a fixed number of days.
Keep the follow-up plan
The early checks assess healing and eye pressure; later review considers the final focus and any glasses needed. Seek urgent advice for increasing pain or redness, worsening vision, new flashes or a sudden increase in floaters.
Why can vision blur months or years after cataract surgery?
The most common reason is posterior capsule opacification (PCO), sometimes called a “secondary cataract”. The cataract has not grown back, and PCO is usually easily treated with a quick laser procedure in the clinic.
Why does PCO happen?
During cataract surgery the cloudy lens is removed, but the thin, clear capsule that held it is left in place to support the lens implant. A small number of the eye’s own lens cells always remain on the inside of this capsule, because they cannot all be removed.
Over months or years, some of these cells can grow and spread across the back surface of the capsule, behind the implant. They form a thin hazy layer, sometimes with fine wrinkles or small clusters of cells, which scatters light and blurs vision.
How common is PCO?
PCO is one of the most common reasons for vision to become blurred again after cataract surgery. Modern lens implant designs and surgical techniques have reduced how often it happens, but some people still develop it, occasionally many years later. It tends to be more common in younger people and in eyes with inflammation.
Typical symptoms are gradually increasing blur, glare from lights or haze, rather like the original cataract.
PCO can cause gradual blur or glare. An examination checks whether it explains your symptoms, because the retina, eye surface or glasses prescription can also affect vision.
How is PCO treated?
When PCO affects vision, a laser can create a small opening in the cloudy capsule. Treatment is usually performed in the clinic after drops. Temporary floaters or inflammation can occur; raised eye pressure, retinal swelling or retinal detachment are possible complications.
Arrange transport if dilating drops are used and follow the advice given about driving and review.
- 1. Just after surgery
- 2. Months or years later
- 3. Clouding blurs vision
- 4. After YAG laser
Common questions about cataract surgery
Will it hurt?
The eye is numbed and most people feel pressure or light touch rather than pain. Some grittiness for a day or two afterwards is normal.
Am I asleep?
Usually not fully. Most people have anaesthetic drops with light sedation and remember little. Sedation helps you feel comfortable and relaxed throughout the procedure. Deeper sedation is available when it suits the person or the eye.
Do both eyes get done at once?
Usually one eye at a time, a few weeks apart, so the first eye can settle and the plan for the second can be refined.
When can I drive and return to work?
Many people return to desk work within a few days. Driving depends on your vision meeting the standard, usually confirmed at the first review.
Can the cataract come back?
No. Some people later develop haze on the capsule behind the new lens, which is cleared with a short laser treatment in the clinic.
Is cataract surgery different after a vitrectomy?
It can be. Vitrectomy often speeds up cataract development, and cataract surgery afterwards can be more technically demanding. Dr Chen regularly performs cataract surgery in eyes that have had vitrectomy, and plans it with the retinal history in mind.
Where can I read more?
Longer articles by Dr Chen go into these questions in more detail, including what the research shows.
Recovery after cataract surgery, week by week Cataract surgery in a short-sighted eye A dark shadow at the edge of vision after surgery Cataract surgery after LASIK, PRK or SMILE: what changes in planning? How do I choose a cataract surgeon in Sydney? Will I need glasses after cataract surgery? Why is my vision blurry after cataract surgery? What different types of cataracts are there? Piggyback lens implants: correcting vision after cataract surgery Ocular dominance: which eye should focus on distance?
For the evidence and practical options, read Can cataracts be treated without surgery?
Cataract surgery after radial keratotomy (RK) explains why repeat measurements, specialised lens calculations and careful wound placement matter, and why a refractive surprise can still occur.
Public or private cataract surgery compares waiting times, surgeon choice, supervised training, lens availability and costs in Australia.
How do I make an appointment with Dr Chen to discuss cataract surgery?
Appointments and enquiries are made through Vision Eye Institute Chatswood.
Level 3, 270 Victoria Avenue, Chatswood NSW 2067For referrers
Optometrists, GPs and ophthalmologists can refer through Oculo or with the PDF referral form.
Vision Eye Institute confirms your appointment after you submit your request. The request form is not for emergencies. A referral is not strictly essential to request an appointment, but you need a valid one to claim a Medicare rebate for your consultation.