What is a cataract – and what does surgery do?
A cataract means that the natural lens inside your eye has become cloudy. This can lead to blurred vision, glare, reduced contrast, difficulty reading, problems with night driving, faded colours, or a general reduction in visual quality.
Cataract surgery removes the cloudy natural lens and replaces it with a clear artificial intraocular lens (IOL). It is one of the most commonly performed eye operations worldwide and is generally very safe and successful. It is, however, still an operation inside the eye – which is why risks and possible complications must be discussed with you.
Explore the eye after surgery
Tap each of the five numbered points to see how the artificial lens sits in your eye after the operation. All five points must be viewed.
The operation is usually performed as a day-case procedure under local anaesthesia. In most cases, anaesthetic eye drops are sufficient; in selected cases, an injection around the eye or sedation may be used. A small incision is made at the edge of the cornea, the front part of the lens capsule is opened, the cloudy lens material is removed, and a foldable artificial lens is implanted into the remaining lens capsule – where it usually remains permanently.
How is the cataract removed?
Click both cards to learn about the standard technique and the optional laser assistance. Both must be opened.
Phacoemulsification Standard
Ultrasound energy breaks the cloudy lens into small pieces, which are gently removed by suction.
Phacoemulsification ("phaco") is a highly established and widely used technique. In most patients it allows a small incision, fast recovery, and excellent visual results. Afterwards, the artificial lens is inserted into the remaining lens capsule.
Femtosecond laser-assisted Optional
A laser assists with selected steps of the operation – it does not replace the surgeon.
The femtosecond laser can assist with: a precise corneal incision, opening the front lens capsule (capsulorhexis), pre-fragmenting the cataract before ultrasound removal, and selected corneal relaxing incisions to reduce astigmatism.
A very precise, round, well-centred capsulorhexis may be particularly helpful when implanting multifocal or EDOF lenses, where accurate positioning and centration matter most. The laser can also reduce the ultrasound energy needed – helpful with very hard lens nuclei, and it may provide additional safety in mature, white, or very dense cataracts.
Please note: conventional phaco remains very safe and highly successful. Laser assistance is an additional option, not a guarantee of a better outcome – and it involves additional costs that may not be covered by statutory or private insurance.
Your artificial lens – four options
The lens is selected before surgery based on measurements of your eye, your visual needs, and the medical condition of the eye. Modern calculations are very accurate, but a perfect refractive result cannot be guaranteed – small residual errors may remain and glasses may still be needed. Click all four lens types.
Monofocal Standard
One main focus – usually set for good distance vision.
You usually see well in the distance, but will normally still need reading glasses for near tasks (reading, phone, close work). Alternatively, the focus can be set for near, with glasses for distance.
Monofocal lenses are reliable, well tolerated, provide good contrast sensitivity, and usually cause fewer optical side effects than multifocal lenses.
Toric Astigmatism
Corrects relevant corneal astigmatism (unequal corneal curvature).
A toric IOL can reduce or correct astigmatism and improve uncorrected visual quality. To work properly, it must sit at the correct axis inside the eye. In rare cases it can rotate after surgery – the correction then weakens, and the lens may need to be surgically repositioned.
Even with a toric lens, glasses may still be required for certain distances or fine visual tasks.
EDOF Premium
Extended depth of focus – for distance and intermediate vision.
Designed for an extended range of vision, especially distance and intermediate tasks: computer work, cooking, the car dashboard, shopping, objects at arm's length. Reduces glasses dependence – but many patients still need reading glasses for small print or prolonged reading.
Possible side effects: halos, glare, reduced contrast sensitivity, or disturbances in dim light – usually milder than with some multifocal lenses, but they can occur. EDOF lenses are more expensive than standard monofocal lenses.
Multifocal Premium
Improves vision at several distances – distance, intermediate, and near.
The main advantage: reduced dependence on glasses. Many patients can read, use a computer, and see in the distance with little need for spectacles.
Because the lens divides light into different focal points, some patients experience halos, glare, starbursts, reduced contrast sensitivity, or difficulties with night driving. These often improve over time (neuroadaptation) but do not disappear completely in every patient. Multifocal lenses are more sensitive to small residual refractive errors, dry eye, irregular astigmatism, corneal scars, macular disease, or glaucoma.
In rare cases a patient may remain dissatisfied despite technically successful surgery – further treatment, laser correction, an add-on lens, or even exchange/explantation of the IOL may then be necessary.
Not every patient is suitable for a premium lens
Multifocal and EDOF lenses may not be recommended in patients with:
If the eye is not suitable for a premium lens, a monofocal or toric lens may provide a safer and more predictable outcome. The final recommendation depends on the examination findings, your visual needs, lifestyle, profession, and expectations.
Recovery and behaviour after surgery
Recovery is usually quick, but varies from patient to patient. Many patients notice better vision within the first days; at first, vision may be blurred. Mild discomfort, watering, foreign body sensation, light sensitivity, redness, or mild pressure can occur. The eye may take several days to several weeks to fully settle – longer with very hard or mature cataracts, corneal disease, dry eye, diabetes, macular disease, glaucoma, or complicated surgery.
Postoperative eye drops must be used exactly as prescribed (usually anti-inflammatory, sometimes antibiotic drops). Follow-up appointments check healing, intraocular pressure, cornea, anterior chamber, IOL position, and retina.
Avoid in the early period
- Rubbing the eye
- Swimming pools
- Sauna
- Heavy dust or dirt exposure
- Heavy physical strain
- Direct trauma to the eye
- Non-prescribed eye medication
Seek urgent review if:
- Severe pain
- Sudden or increasing loss of vision
- Increasing redness or light sensitivity
- Discharge from the eye
- Flashes of light or many new floaters
- A curtain or shadow in the visual field
- Nausea or headache with eye pain
Possible risks and complications
Cataract surgery is generally very safe, but complications may occur – some mild and temporary, others rare but potentially serious. Open every single item and confirm it with the button inside. Your consent is only valid once all items have been confirmed as read.
Alternatives, limitations, and individual planning
Alternatives: If the cataract is mild and does not significantly affect daily life, surgery may be postponed. Glasses, better lighting, or magnifying aids may temporarily improve vision. However, cataracts usually progress over time, and no eye drop or medication can reliably remove a cataract. Once the cataract significantly affects quality of life, driving, work, reading, or the ability to examine or treat other eye diseases, surgery is usually recommended.
Limitations: Cataract surgery can significantly improve vision if the cataract is the main cause of the visual reduction. The final result also depends on the health of the cornea, retina, optic nerve, and brain pathways. Conditions such as macular degeneration, diabetic retinopathy, glaucoma, optic nerve disease, amblyopia, corneal scarring, keratoconus, previous retinal disease, or previous trauma may limit the improvement – cataract surgery cannot fully correct visual loss caused by these conditions.
Individual planning: The choice of technique and lens type takes into account cataract density, corneal shape and astigmatism, corneal health, axial length, anterior chamber anatomy, retinal and optic nerve status, dry eye, lifestyle, profession, reading habits, night driving, your wish for spectacle independence, your tolerance of possible optical side effects, and budget/insurance coverage. Your surgeon will recommend the option that appears medically suitable and realistic for your individual eye.
Did you understand everything? – Quick check
Three short questions – all three must be answered before the consent section unlocks.
1. What happens during cataract surgery?
2. What is posterior capsule opacification ("after-cataract")?
3. Can glasses still be needed after successful cataract surgery?
Your declaration of consent
Before you can sign, the following must be completed:
- Eye diagram: all 5 points viewed (0/5)
- Surgical technique: both cards opened (0/2)
- Lens options: all 4 lens types opened (0/4)
- Risks: all items opened and confirmed (0/0)
- Comprehension check: all 3 questions answered (0/3)
The informed consent is not valid until every item above has been clicked and confirmed.