What is a cataract?

Cataract: ‘A clouding of the lens within the eye that is reducing vision.’

Consultants and optometrists can diagnose a cataract at various stages, whether it is severely affecting a patient’s vision or even if a patient’s vision is still normal and they cannot notice any haziness yet. 

There are different types of cataracts and various factors as to why a cataract might develop, but the main cause in the developed world is typically age-related. In young children, the lens of the eye is clear and transparent. As we age this lens gradually becomes more opaque and can turn a creamy white or yellow colour. In the elderly the lens of the eye frequently has a brown hue to it.

It is often misunderstood that a cataract is a skin that forms on the eye, which is simply not the case. All cataracts form within the lens, which is shown in Figure 1.2.

Figure 1.1 - Cortical cataract

When is Cataract Surgery Needed?

The only treatment for a cataract is surgery, which should be tailored and timed to suit a patient’s individual needs and vision requirements.

Some individuals will need or want a cataract to be removed sooner than others; for example, if the patient wishes to continue driving or requires clear vision for the purposes of sport or work. In these instances, surgery is performed whilst the cataract is relatively mild.

However, if the patient has no immediate need or visual requirements for a cataract to be removed, then it may be appropriate to leave the cataract to develop until it is more advanced.

In any case, the decision whether to operate should be based on the individual circumstances and wishes of each patient, along with the risks, benefits and medical opinion from your consultant ophthalmologist.

Patients should consider how much difficulty their cataract is causing them and whether there is a genuine need for surgery. Often when a cataract is diagnosed early on by an optometrist or consultant and there is no disturbance of vision, then surgery is not recommended until the cataract has developed further.

It’s also important to refer to the legal requirements for driving or performing other tasks safely in accordance with government guidance, and seek professional advice if your eyes no longer meet these requirements.

Ultimately however, even if a cataract is noticeable and impacting your vision, it is the patient’s choice whether they wish to proceed with surgery. If an individual is suffering from cataracts or experiencing any form of discomfort, then surgery can be the solution to restore vision and quality of life.

Watch a video of live cataract surgery being performed above – Please note viewer discretion is advised due to scenes of a surgical nature.
Schematic picture of the eye
Schematic picture of the eye.

Special Factors

There are sometimes additional factors that may influence the  decision on whether to perform cataract removal surgery;
these include:

  • Other diseases or abnormalities present in the eye.
  • The cataract is present in only one eye.
  • Whether leaving a cataract in the eye could be harmful to the eye or vision – although this is rare.

For specific advice on the timing of cataract surgery, patients should discuss their individual circumstances with their consultant ophthalmologist.

What does Cataract Surgery involve?

Cataract surgery has evolved substantially since the turn of the 21st century thanks to technological advancements. Surgical procedures are now usually carried out under local anaesthetic and can take as little as 15 minutes on the operating table. This allows patients to be able to return home the same day as their operation with a minimal recovery period and quicker noticeable improvements to vision. 

It’s important to note that surgery times can differ depending on the complexity of a cataract, as well the lens used and factors specific to each patient. Always speak to your consultant ophthalmologist if you’re unsure or have any questions.

The operation involves removing the cloudy natural lens which has developed a cataract and inserting an artificial clear plastic lens, commonly known as an intraocular lens implantation (IOL).  

What is Phacoemulsification?

The Phacoemulsification tip used during surgery
Figure 1.3 - The phacoemulsification tip used during surgery.
Most cataract operations now performed in the UK use a method called phacoemulsification, in which the cataract is broken up and emulsified using an ultrasonic handpiece. The cataract fragments are then aspirated, which means they are essentially sucked out of the eye. This method allows smaller incisions in the eye, approximately 3mm in length for the instrument tip to be inserted. This also means that sutures in the eye are rarely required.

During the procedure, fluid is continuously flushed through the front part of the eye to help keep the eye inflated and flush out cataract debris. Once the original lens and cataract debris have been completely removed, all that remains is the thin membranous outer shell of the natural lens, called a capsular bag. This bag provides the perfect support for the new IOL to be inserted into. To minimise the incision size, many surgeons use foldable IOLs. These artificial lenses come preloaded and already folded, and simply insert straight into the existing lens bag. The surgeon then helps to unfold the lens and position it correctly. 

As there are multiple types and features of a cataract, a different surgical approach may be needed. For example, it may be necessary to use a larger incision to remove the cataract from the eye in one main place, in which case sutures are required. 

The Intraocular Lens Implant

The intraocular lens implant (IOL) is now a standard part of a cataract surgery. Patients who decide not to proceed with cataract surgery to improve their eyesight may find glasses or contact lenses help to increase their vision, although not to the extent that surgery would. Spectacle lenses are often thick, heavy and can restrict the field of vision, whilst contact lenses must be replaced daily and are not suitable for all patients. With an IOL, once inserted and when the patient has recovered from surgery, vision will usually return to a nearly natural state, similar to before cataracts had formed. The lens will last the patient’s lifetime and can largely be forgotten about. 

It is important to note that some patients may develop clouding at the back of the lens implant following cataract surgery, known as posterior capsule opacification (PCO). Patients who experience this complication find that symptoms can occur months or sometimes years after surgery. The procedure is very quick and involves a YAG laser. For more information see our patient information guide on YAG Laser treatment.

Which lenses are available to me?

Whilst all cataract surgeries use an IOL, there are multiple types of lenses which offer different benefits and drawbacks. For further information on the different lens options available to you, speak to your consultant ophthalmologist and study any lens leaflets you have been given.

Risks of Cataract Surgery

As with all surgical procedures, there are possible risks and complications of cataract surgery patients need to be aware of, including but not limited to:

  • Infection within the eye, called endophthalmitis
  • A disturbance to the retina, such as cystoid macula oedema or retinal detachment
  • Permanent clouding of the cornea
  • Intraocular bleeding
  • An unacceptable position of the intraocular lens implant
  • Technical problems during surgery
  • A need for a follow up surgery
Along with these, there is also a risk of reducing your vision to a level that is worse than before surgery, although the chances of this are incredibly low and are thought to be in the region of 1% or less of patients. There is an extremely remote chance of losing all vision in the eye, such as from a severe intraocular infection. Whilst the chances of experiencing any of the above are very low, it’s important that all patients discuss the risks in depth with their consultant ophthalmologist.

Lens options


The standard monofocal lens is the one most people opt for. After surgery your vision will be better, but in most cases, you will still need glasses to help focus with near and/or distance vision. You may also need distance glasses depending on issues such as astigmatism.


This option is only available through a private procedure. Similar to bifocal or varifocal glasses, multifocal lenses will result in improved vision for reading and distance, without the need for glasses in most cases. Some patients who choose multifocal lenses will also require glasses, but most activities can be performed without them.


For patients with astigmatism, a toric lens can correct the astigmatism and reduce the need for glasses with thicker lenses.

Private cataract surgery gives you a wider choice of treatments than are available on the NHS, meaning they can be personalised to suit you. Please ask one of our team if you are interested in any of the treatments described above.

What happens on the day of surgery?

We’ve created an animated video which explains what happens on the day of cataract surgery. This includes different people you’ll see, and steps both before and after the surgery. 

Please note that there are no surgical scenes in the video.


It is normal to feel itching, sticky eyelids and mild discomfort for a while after cataract surgery. Some fluid discharge is common. If you have discomfort, we suggest that you take paracetamol up to 4 times a day leaving at least 4 hours between doses. For a few days the eye may feel dry as if there is something in it and may be slightly sticky in the morning, this is normal. The eye should feel progressively more comfortable each day.  You will be given eye drops to reduce inflammation. The hospital staff will explain how and when to use them. Certain symptoms could mean that you need prompt treatment, including:

  • Increased pain
  • Paid loss of vision
  • Increased redness, or discharge
  • Flashes of light, floaters (black spots) or a curtain across your vision

The standard monofocal lens is the one most people opt for. After surgery your vision will be better, but in most cases, you will still need glasses to help focus with near with near and/or distance vision. You may also need distance glasses depending on issues such as astigmatism.

A member of the team will call you on the day after surgery to check how you are doing, and to answer any questions you may have.

Aftercare Do's

Most people still need glasses after cataract surgery. The chance of not needing glasses after cataract surgery depends on many things. These include your personal vision requirements, the presence of any astigmatism, and the choice of lens implant (monofocal, toric, multifocal, or monovision). Your consultant will explain this to you. The eye changes shape as it is healing, and your glasses prescription will alter during this time. If you are very keen to read with the eye that has just had surgery with a distance focus implant. 

  • You will need to update your glasses four to six weeks after your operation. 
  • You can buy an off-the-peg pair of reading glasses at minimal cost.
  • You will not harm your eyes by using an old pair of glasses or an approximate glasses prescription.

Aftercare Dont's

If you are a glaucoma patient, remember to open a new bottle of eye drops and continue using the eye drops as prescribed.  If required use clean water (boiled then cooled) and clean gauze or tissues to wipe any discharge from the lids. If a pad or shield has been placed on your eye, remove it and discard the following morning then clean your eye as the instructions below:

  • Please do not rub your eye.
  • Wash your hands thoroughly with soap and water at all times.
  • Clean your eye as required with cotton wool, gauze or clean tissues, moistened with cooled boiled water.
  • If there is no cover on the eye after surgery, just use the drops straight away and clean as required.
  • Use the eye drops as prescribed, usually 3 – 4 times a day for 4 weeks.
  • You can shower or bathe as normal but try to keep dirty water and soap away from your eye.
  • Wear sunglasses if you wish.

In case you develop any of the above symptoms, or should you need urgent advice about your eye, please call our emergency number: 0116 243 7373.

What are the Costs of Surgery?

Prices largely depend on the type of lens a patient chooses and are separate to any consultation fee initially. Surgery prices for phacoemulsification cataract surgery are as follows:

  • £2600 – £2850 per eye
    – Surgery with a monofocal lens
  • £3300 – £3850 per eye
    – Surgery with a multifocal lens

Two post-operative follow up appointments are also included.

If you have any further questions, please don’t hesitate to contact our friendly team and we’ll be happy to help.

How can I fund my Surgery?

Patients have the option of choosing how they wish to pay for their private surgery through The Stoneygate Eye Hospital. There are three routes for payment:

  1. Privately insured patients, where your insurance company will pay for part or all of the surgery cost. We advise checking your cover limits and any excesses you may need to pay with your insurance company.
  2. Self-pay patients, with patients paying the full cost of surgery upfront, either by bank transfer prior to the day of surgery or on the day with our chip and pin card machine.

  3. Patients can make use of the 0% finance package over 12 months on any surgeries over £1000 offered by Chrysalis Finance – subject to status, credit checks and applications apply. 


Information on consultant’s individual fee structures can be found on their bio pages, which can be found in the drop-down menu at the top of the website, or by clicking here.

0116 270 8033