What is a cataract?
We are all born with a clear lens near the front of the eye. If it becomes cloudy, it is called a cataract.
What causes cataract?
The most common cause is age. Cataract formation is essentially a normal part of the ageing process, although different people develop cataracts at different ages. Other rarer causes include eye injuries, inflammatory eye disease, diabetes, and use of certain medications such as steroids.
Can cataract development be prevented or slowed down?
There is no evidence to support any tablet, supplement or eye drop in preventing the development and/or progression of cataract. Cataracts are not caused by using the eyes too much.
What are the symptoms of cataract?
Patients with cataract can experience blurring or mistiness of vision, and often glare – either in bright sunlight or with on-coming headlights when driving at night. Cataracts can also cause the vision to become dimmer and yellowed. Occasionally cataract can cause a type of double vision or ghosting of images.
Cataracts do not generally harm the eye, and they do not cause watering or discomfort. If you have symptoms like grittiness, dryness, burning, ache or even eye pain, they are unrelated to the cataract and should be evaluated by your eye surgeon prior to you undergoing cataract surgery.
Are there any alternatives to surgery?
In the early phase of cataract development, the progressing cataract can make the eye more short-sighted (or less long-sighted, if the eye is long-sighted to begin with). This can initially be dealt with simply with more frequent changes in the glasses prescription. As the cataract progresses, it becomes cloudy and altering the glasses will no longer help the vision. Fundamentally the only cure for cataract is to remove it with an operation.
This video, from the American Academy of Ophthalmology, contains a 3D animation to explain the process of cataract extraction and lens implantation.
Should I have my cataracts removed?
Since cataracts almost always get worse with time (albeit slowly), perhaps a more appropriate question to ask is ‘when should I have my cataracts removed?’
Cataracts are not like some medical conditions, in that the cataract cannot harm the eye (except if you have or are at risk from primary angle closure, which your optometrist or eye surgeon will tell you). Importantly, delaying the operation does not prejudice the final visual outcome from the operation, (unless the cataract is already very advanced). Therefore the main reason to have cataract surgery is if you want your vision to be clearer. If you have a high glasses prescription, then reducing your dependence on glasses is another reason to consider having surgery. Your eye surgeon should counsel you on the risks of surgery – which are often different from one patient to another, depending on various factors such as the configuration of your eyes, your medications and medical history, etc. It is then up to you to decide whether to go ahead. In general terms, if you consider that you have good vision, can see everything you need to see, and your vision is not adversely impacting on your quality of life or activities, then cataract surgery is probably not required. One exception to this is if you drive and if your cataracts are causing your vision to approach the prescribed legal standards for driving vision in your jurisdiction. If this is the case, your optometrist or eye surgeon will let you know. Please note that the visual standards for driving are different in Jersey compared to the UK and EU.
Will I be awake for the operation?
Over 90% of patients can safely undergo cataract surgery under local anaesthesia. All of Mr Shah’s private patients are also under the care of a Consultant Anaesthetist for their surgery. The anaesthetist delivers local anaesthetic around the eye, so it is very rare to feel any pain during the operation. If the operation does start to become uncomfortable, Mr Shah can top up the local anaesthesia during the surgery. If you are very anxious, you can request either sedation or general anaesthesia (being put to sleep) but your eligibility for these will depend on the anaesthetist’s assessment of your general health. If you are claustrophobic, you may also benefit from sedation, because the operation is carried out with a sterile drape over the top half of the face (but it lifts up off the nose and mouth so you can breathe normally).
Should I take my normal medication?
Please inform Mr Shah prior to your operation of any medication that you use, including eye drops, inhalers etc. Generally speaking, if you are having a local anaesthetic, you can take your medication as normal on the day of surgery.
Do I need tests prior to surgery?
Modern cataract pre-operative assessment may include any or all of the following tests prior to surgery:
- Ocular Biometry – measures the length and curvature of your eyes so that the correct power of lens implant can be chosen to give you clear vision after surgery. If you wear soft contact lenses, Mr Shah will ask you to remove them for at least 1 week prior to the measurements so that we have the most accurate measurements possible. If you wear Rigid Gas Permeable contact lenses, Mr Shah will normally ask you to remove them for longer, depending on how many years you’ve been wearing them for. If you absolutely rely on contact lenses for clear vision, it it normally possible to have one eye measured at a time, so that you avoid being completely without contacts in both eyes for any period.
- Macular OCT scanning – this is increasingly becoming a standard part of cataract assessment, as subtle problems on the macula (the central part of the retina) such as vitreomacular traction, epiretinal membrane, or diabetic retinopathy can significantly affect your visual prognosis, choice of lens implant, and even refractive targeting strategies.
- Visual field testing – Mr Shah may order this test if your symptoms are not typical for cataract, or if part of your medical or eye history suggests that part of your visual field may be affected (for example, previous stroke)
- Corneal topography – this measures the front and back curvatures of the cornea (the clear window at the front of the eye) and also provides information on astigmatism, spherical aberration, and angle kappa – all of which can be important information for the surgeon, especially when considering certain types of lens implant.
What does the surgery involve?
The cataract is removed by a special machine through a tiny incision that is just over 2 millimetres in size. The machine makes a few funny noises, that you will hear if you are awake for your surgery. Most patients having a local anaesthetic injection don’t see much out of the operated eye during surgery. Sometimes it is possible to see vague movements and fuzzy colours during the operation, but the images are usually very blurred and are not distracting. A clear lens implant is then placed into the same place in your eye that your natural lens occupied. The lens implant is folded up like a rug so that it fits through the tiny incision – it unfolds to its full size once inside the eye.
When can I go home after the procedure?
Following the procedure you will be taken to your room where you will be offered some refreshments. After a short while you will be able to go home.
What are the benefits of cataract removal?
- Improved quality of vision – by replacing your cloudy lens with a clear lens implant, the operation offers a very good chance of improving your vision – over 95% if the operated eye is otherwise healthy.
- Reduced dependence on spectacles – most people who require glasses for distance will experience a reduction or sometimes complete resolution in their dependence on spectacles.
- Improved view of the back of your eye – by replacing your cloudy lens with a clear lens implant, the operation improves the view that your eye surgeon or optometrist can get of the back of your eye. If you have a condition like glaucoma or diabetes which requires regular monitoring of the health of the back of your eye, the operation can improve the accuracy of your future tests and eye examinations.
Are there any side effects or risks to the procedure?
All surgical procedures, no matter how big or small, carry a risk. Many of the risks of cataract surgery are unusual, quite technical, and difficult to explain. Some of them include infection inside the eye, a bleed inside the eye, retinal swelling, and retinal detachment. According to the latest national data, in approximately 1 in 85 cases, the capsule behind the lens can develop a break during surgery, which can either allow fragments of cataract to enter the back of the eye, or alternatively allow the vitreous gel – which normally fills the back of the eye – to enter the front of the eye. Mr Shah’s rate of this complication is significantly lower than this national level, but even if this happens, Mr Shah can normally complete the operation safely after a few additional steps.
The main consequences of any risk of surgery are either poor vision and/or needing a second operation to the same eye. Otherwise healthy eyes that undergo cataract surgery have a 96-98% chance of seeing better after the operation. Accordingly, it is considered one of the most successful surgical procedures available. The risk of seeing worse is 2% or less. The risk of serious or total loss of vision in the operated eye is stated in national guideline documents to be 0.1% (1 in 1000) – but in our experience is significantly lower than this.
When the cataract has been replaced with a lens implant, observers of the operated eye may notice a subtle glimmer coming from the centre of the pupil in the eye. This is a normal observation inherent to the lens implant itself, and just represents reflections of light arising from the lens implant, which can be visible to the close observer. A small number of patients can experience certain curious visual phenomena after lens implantation, and these almost always get better after a few months, as they adapt to the new quality of vision:
- Positive dysphotopsia – streaks or starbursts of unwanted light, or an arc of bright light due to light entering the eye at a particular angle which can catch the rim of the lens implant and cause the rim of the implant to light up
- Negative dysphotopsia – a dark shadow or arc, seen on the outside field of vision of the affected eye, which is noticed more in the daytime / in bright lighting conditions
- Shimmering or flickering of the vision – noticed in the early weeks of surgery, due to the lens implant taking time to settle into the capsular bag.
Does cataract surgery use a laser?
No, but this is a widely held misconception. Cataract surgery machines use ultrasound, not laser, to remove the cataract. In recent years, some companies have developed lasers to help with some parts of the cataract operation, but since lasers cannot fully break up the cataract, the ultrasound machine is normally still required anyway. Consequently the vast majority of ophthalmic surgeons have failed to see any benefits of using lasers for cataract surgery and do not use these methods, as they seem to pass on significantly increased costs of surgery without offering many practical benefits. Finally, many investigators have found that using lasers to help with cataract surgery in this way actually increases the rate of surgical complications (see blog posts). The latest clinical evidence directly comparing laser-assisted to conventional cataract removal (published in 2019) again demonstrates virtually no meaningful advantages of femtosecond laser-assisted cataract surgery in terms of outcome for patients.
What sort of recovery period is involved?
The eye will sometimes feel a little gritty, scratchy, achey, or uncomfortable for around 2-3 days after surgery, but this usually responds to normal painkillers such as paracetamol and/or ibuprofen. The white of the eye can also look red (occasionally dramatically so) which is usually due to bruising caused by the anaesthetic rather than the operation itself, and is of no concern. All these symptoms gradually subside over the first few days. The vision is sometimes hazy for a day or two but quickly recovers. Overall, most people are back to their normal routines within a few days of their operation.
Will I need glasses after surgery?
This requires a detailed discussion between patient and surgeon. It depends on what your current glasses prescription is, which focal distance your surgeon is aiming for, what type of lens implant you are receiving, and whether you are having any simultaneous procedures to reduce astigmatism (if relevant).
A variety of premium lens implant technologies are available that can reduce your dependence on glasses after surgery. This area is constantly evolving and each patient needs an individualised consultation.
If you do need to change your glasses after cataract surgery, you should wait at least 4 weeks before seeing your optician, as the prescription of your eye can change while the eye is settling down initially after surgery. You might also find that you need some time for the brain to adapt to your new glasses prescription after surgery.
Following the procedure
- Leave the pad and shield on until the following morning, when you should remove them gently
- On the day after surgery, start using your drops as prescribed, but do not touch your eye with the tip of the bottle of eye drops
- You can resume normal activities around the home the day after surgery
- Avoid heavy lifting and strenuous exercise for 2 weeks
- Avoid dusty environments and activities for 2 weeks
- Do not rub your eye for 2 weeks
- Do not swim, or get tap/shower water into your eye, for 3 weeks
Can I drive home?
You will not be able to drive home or use a mobility scooter to get home after your procedure. Please bring a companion, or make suitable transport arrangements, so you can get home afterwards. Whether you can drive after your surgery depends on your level of vision in both eyes, so you will need to discuss this with Mr Shah at your consultation.
How many cataract procedures has Mr Shah carried out?
As of 2019, Mr Shah has performed over 2000 cataract operations. He has been involved in teaching cataract surgery to junior surgeons both in London and Jersey, and his audited index complication rate during cataract surgery is considerably lower than nationally published rates.
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