30 May 2019
If you’re reading this article it’s likely that you’re amongst the 7 out of 10 people in the UK that are dependent on glasses or contact lenses. Fortunately, modern refractive surgery offers a range of solutions that can give you clear, unaided vision at all distances. Our Consultant Ophthalmic Surgeon, Mr Dipak N Parmar, has over 20 years of experience in refractive surgery and has provided a guide on the maze of treatments that are currently available.
The surgical options available to you broadly depend on age and patients can usually be divided into two groups; those under 40 years old, and those above 40. The significance of this threshold is that, over the age of 40, the natural human lens gradually becomes less flexible. Less flexibility means a reduced ability to focus on nearer objects, and by about 60 years old this flexibility is almost lost completely. This condition is called ‘presbyopia’ (literally ‘ageing of the lens’), a natural process that happens to most people, which results in the need for reading glasses.
Many patients seek out laser vision correction surgery for short sight (‘myopia’) or long sight (‘hyperopia’), which works by reshaping the cornea to alter the optical power of the eye. However, not all patients are suitable for laser vision correction, for example patients with very high prescriptions or thin corneas. We are able to offer an alternate approach using lens-based surgery by either (a) replacing the natural lens with multifocal intraocular lens implants or, (b) using additional implants to modify the power of the eye in (i) those patients who have not had previous surgery and (ii) those who already have a single focus implant in place from previous cataract surgery.
1. Under 40 years of age
This patient group is ideally suited to laser vision correction by reshaping the cornea. Although unavailable at Spire London East Hospital, Mr Dipak Parmar is able to advise you with regard to your suitability for treatment. He can offer alternative lens-based surgical options if necessary, particularly in cases with very high optical prescriptions or thin corneas. For example, an ‘implantable contact lens’ can be placed inside the eye and sit in front of your own natural lens to provide the extra ‘boost’ of optical power to allow you to see well at distance. Near vision is not a problem as your own natural lens is pliable and flexible enough at this age to be able to focus for close work.
2. Above 40 years of age
As we get older, the natural lens loses its ability to be flexible enough to change power to see near targets. This can also happen years after laser vision correction. Typically, these patients would have to wear reading glasses, but it’s possible to gain freedom from these too:
a. Age 40 to 50 years:
i. Blended vision
This gives the best of both worlds; one eye is corrected for distance and the other eye is corrected for near vision. This is achieved by setting the dominant eye’s optical power to zero and the non-dominant eye is offset to allow near vision, and can be achieved by either laser or lens-based techniques. After this procedure if you close one eye you can have blurred vision, however, with both eyes open many patients can achieve excellent vision at all distances. Blended vision is usually tolerated in around 60 - 80% of patients and is not suitable for patients who read for longer than 30 minutes at a time.
If you’re considering this option, it is important to have a simulation with a ‘contact lens trial’ to see if the procedure would work for you. One of the disadvantages of blended vision is a slight loss of depth perception, although most patients do not find this to be a problem.
ii. Full distance correction
Often a popular option, laser vision correction can still be offered if you’re happy to wear reading glasses for close work.
b. Over 50 years:
Multifocal intraocular lens implant
Natural lens replacement with multifocal intraocular lens implants is tailored to the patient’s needs. For the maximum benefit, both eyes need implants. The technology has advanced hugely over the last decade, and there are now first-rate choices available which give excellent unaided vision at all distances. The implants work by giving ‘zones’ of vision; they split light energy into different areas to give excellent vision at different distances (the implants work best in bright light).
A period of adaptation is needed to maximise visual outcome, as many patients will
develop temporary visual haloes for the first few months. These tend to settle and typically do not cause problems as the visual system adapts. Some of the most recent implants can offer trifocal correction to give excellent vision at far (driving), intermediate (computers) and near (reading) distances.
c. Patients who have already had cataract surgery (typically over the age of 60 years)
‘Add-on’ multifocal lens – Sulcoflex®
Many patients over the age of 60 years have already had cataract surgery with single-focus intraocular lens implants. This renders them dependent on reading glasses, and these patients often struggle once the joy of removing their cataracts has elapsed. A truly exciting development for this patient group is the option to insert an ‘add-on’ multifocal implant to provide an optical ‘boost’ to correct near vision, removing the need for near vision glasses. An example of such an implant is the Sulcoflex® by Rayner®, which I’m able to offer at Spire London East Hospital, having gained specialist certification in its use.
Refractive surgery is only available through private healthcare, as it is considered a lifestyle enhancing procedure, and therefore currently generally not offered by the NHS. This includes laser vision correction surgery, ‘add on’ implants for refractive correction and natural lens replacement cataract surgery with multifocal intraocular lens implants.
Are there any risks to refractive surgery?
There are risks with any form of intervention, however the risk profile can be minimised by careful screening of patients to optimise outcomes. The vast majority of patients who have undergone such procedures have had excellent results with minimal complications.
An important step is choosing a Consultant Ophthalmic Surgeon who has received specific subspecialty fellowship training in refractive surgery, including laser and lens replacement techniques. I’m unique in having undergone specialist training in both the UK and USA; at Moorfields Eye Hospital in London followed by subspecialty fellowship training in cataract, corneal and refractive surgery at the University of Texas Southwestern Medical Center, Dallas, USA.
Which procedures are available at Spire London East Hospital
Spire London East Hospital is equipped with some of the most advanced diagnostic and surgical equipment to provide optimal results and minimise complications for lens replacement surgery with multifocal implants.
I am able to offer the whole spectrum of refractive surgical solutions through consultations at Spire London East Hospital. With 20 years of experience, I specialise in natural lens replacement cataract surgery with multifocal intraocular implants. My most recent focus is on the Sulcoflex® implant which is an ‘add-on’ trifocal implant that offers patients who have already undergone standard cataract surgery the opportunity to gain near vision, and freedom from reading glasses.
What are the lifestyle benefits?
Removing your dependence on glasses can open up a world full of possibilities. It can give you increased freedom to enjoy all activities such as reading, computing, swimming, snorkelling, driving, cycling and numerous other outdoor activities, without the hindrance of spectacles or contact lenses. You could lose the constant headache and dependence on having to carry glasses with you everywhere, even if you have already had cataract surgery.
The content of this article is provided for general information only, and should not be treated as a substitute for the professional medical advice of your doctor or other health care professional.