Common questions about eye problems

Q. What are London Vision Clinic’s results with myopic (short-sighted) patients?

100% of all patients with myopia treated at London Vision Clinic reached the UK driving standard of “20/40” vision or better. Indeed, 97% of myopic patients with prescriptions up to -4.50 dioptres attained vision better than “20/20” vision (20/16 vision). This chart reflects our most recent results with myopic patients.

Q. How does laser eye treatment help myopia?

The need to wear glasses or contact lenses is usually removed by myopia laser treatment and this ability to see clearly without aid is of particular benefit to any myopic person who enjoys sport or leads an active life. Many myopic individuals also find it helps in social situations where faces can be more easily recognised

Q. What are the alternatives to treating myopia?

Optometrists traditionally treat myopia, in all but it most extreme forms (above -12.50 dioptres), with glasses or contact lenses. This makes myopia an ideal condition to treat with either LASIK or PRK. We can treat more severe myopic prescriptions beyond -14 dioptres, but in these cases, we usually recommend Intra-ocular lenses (IOL).


Q. What is myopia?

In myopic patients, the eyeball is slightly longer and flatter than the lens requires. As a result, light entering a myopic eye converges just before the retina (where the image is formed) and the resulting vision is blurred and out of focus.

There are a number of forms of myopia, but amongst the most common are physiological myopia, pathological myopia and acquired myopia.

Physiological myopia is a simple physical mismatch between the length of the eyeball and the focusing power of the lens and cornea. It is by far the most common form of myopia. Physiological myopia will normally develop in children between the ages of five and ten and continue to worsen until the myopic eye stops growing.

Pathological myopia is far less common and, whilst it begins as physiological myopia, it does not stabilise with age, and the eye continues to enlarge at an abnormal rate. Laser eye surgery can help in the treatment of pathological myopia, but it is a complex condition and one that is beyond the scope of this website. If however you should wish to discuss y our myopic condition we would be happy to arrange a consultation.

Acquired myopia occurs after infancy – often because of uncontrolled diabetes or certain forms of cataracts.

Q. What are London Vision Clinic’s results with hyperopic (long-sighted) patients?

Hyperopic patients at London Vision Clinic perform exceptionally well when compared to data concerning hyperopia published in scientific literature or presented at major medical conferences.

Over 98% of hyperopia patients achieve “20/32” vision – better eyesight than the UK driving standard of 20/40. Indeed, the results for hyperopia patients with prescriptions up to +2.00 dioptres are even better with 97% of them reaching “20/20” vision.

Q. How does laser eye surgery help hyperopia?

Many hyperopic patients will have found that their eyesight has deteriorated slowly over time, this is quite normal, but it can be frustrating for a hyperopic individual who needed no correction when young to find they need glasses to read and perform close work.

Laser eye surgery can return eyesight to a condition before hyperopia so patients usually no longer need to wear glasses, to fiddle with contact lenses, nor struggle to focus.


Q. What are the alternatives to treating hyperopia?

In the developed world, most suffers of hyperopia will already be aware of their condition and, by the time they are in their mid-twenties, hyperopic patients will either be wearing, or considering wearing, glasses or contact lenses to counter the effects of hyperopia.

London Vision Clinic can correct hyperopia through using one of two laser eye surgery techniques, LASIK or PRK.

Q. What is hyperopia?

Hyperopia, often called long-sight, results from a disorder rather than from a disease. In hyperopia, the eyeball is slightly shorter and fatter than the eye’s lens requires, so that the point of focus is not directly on the retina (where the image is formed), but at a point some way behind it.

As a result, hyperopia sufferers can see distant objects well, but have difficulty focusing on objects that are near. Sufferers of mild hyperopia can often sharpen the image of close objects by making a conscious effort to focus and hyperopia may therefore lead to headaches.

Hyperopia is a relatively common condition affecting about one in every four people. People usually inherit hyperopia, and nearly all babies actually start life hyperopic – this hyperopic condition lessens as they grow.

Q. How does laser eye surgery help astigmatism?

The blurring of small print, difficulty reading, the inability to see both near and far without squinting, constant headache and fatigue are all symptoms that will be familiar to someone suffering from astigmatism. Laser eye surgery can usually alleviate these astigmatism conditions without the need to wear glasses or specialist contact lenses.

Q. What are the alternatives to treating astigmatism?

Treating astigmatism is slightly more complex than treating either myopia or hyperopia because astigmatism requires correction in more than one plane. Think of myopia or hyperopia as an eye that is simply ‘out of tune’ – like a poorly focused telescope. Astigmatism on the other hand is more akin to distorted glass – any correction must take account of every astigmatic distortion.

Optometrists traditionally have treated astigmatism by the use of cylindrical lenses, in the form of either glasses or contact lenses. In the hands of a laser eye surgeon, it is possible to correct astigmatic vision using LASIK or PRK.


Q. What is astigmatism?

The outermost part of the eye, the cornea is a transparent layer that covers the iris, the pupil, and the lens. Rather than being a simple ‘window’, the cornea refracts or bends light and helps to focus it onto the retina. Any irregularity in the cornea’s shape therefore results in incorrect focusing of light and in blurred vision. In short, astigmatism is image distortion that results from an improperly shaped cornea.

A normal cornea is spherical, with astigmatism however, the cornea is elliptical -more like a rugby ball. The effect is that light passing through an astigmatic cornea will have two points of focus and not create a single, sharp image on the retina.

Problems with the lens of the eye cause a less common version of astigmatism, known as lenticular astigmatism. In lenticular astigmatism, minor irregularities in the curvature of the lens produce small degrees of astigmatism despite the cornea being normal.

Q. How does laser eye surgery help presbyopia?

Presbyopia sufferers often find the need to swap glasses in order to read or drive can become tiresome. However, the decision to undergo surgery to remove the inconvenience presbyopia causes is not a simple one and often comes down to personal preference.

So that presbyopic patients can decide if PRESBYOND® Laser Blended Vision suits their lifestyle and needs, London Vision Clinic can perform at test to simulate the effects of PRESBYOND® Laser Blended Vision laser treatment.

Q. What are the alternatives in improving reading vision?

Presbyopia and the need for bifocals is a sure sign of the passing time, however there are other solutions. For presbyopic individuals who wear glasses and would rather not, PRESBYOND® Laser Blended Vision offers a remedy to presbyopia.

The laser eye procedure to correct presbyopia or ‘ageing eyes’ involves a technique called PRESBYOND® Laser Blended Vision. With this technique, one eye is treated to view objects mainly at distance, but a little up close, and the other is treated to view objects mainly up close, but a little at distance. The brain puts the two images together and enables the individual to see distance and near without effort. In most cases, the brain is able to compensate and you will experience an excellent depth of focus and overall visual acuity, without the need to wear glasses or contact lenses.

Q. What are the differences between PRESBYOND® Laser Blended Vision and monovision contact lenses?

PRESBYOND® Laser Blended Vision is not to be confused with traditional monovision – a practice in which the contact lenses are set with one eye for near and one eye for distance. The difference with the PRESBYOND® Laser Blended Vision technique is that the PRESBYOND® Laser Blended Vision near eye sees much better at distance than the near eye set with traditional monovision, similarly the PRESBYOND® Laser Blended Vision distance eye sees more up close than the distance eye with traditional monovision. Because PRESBYOND® Laser Blended Vision is milder than monovision, far more people are able to adapt to it than to monovision. Approximately 95% of people are candidates for PRESBYOND® Laser Blended Vision as compared to about 50% for traditional monovision.


Q. What is presbyopia?

Presbyopia is part of the aging process and presbyopia means, literally, ‘old eye’. With presbyopia, the ability to focus on close objects gradually decreases over a number of years, with presbyopic symptoms usually becomes noticeable around middle age.

With presbyopia, the lens steadily becomes less flexible, and the muscles that pull it into focus become less powerful. As presbyopia develops our ability to adjust to vision at various distances decreases, and most noticeably, presbyopia causes near objects to appear blurry and difficult focus. Indeed, presbyopia sufferers often unconsciously adjust the distance between page and eye to compensate for their presbyopia.

Q. What is keratoconus?

In keratoconus, a serious form of astigmatism, the cornea progressively thins towards its edges causing a cone-like bulge to develop and resulting in significant astigmatic impairment. In the early stages it is possible to treat keratoconus with glasses or contact lenses, however, as the keratoconic disorder progresses and the cornea continues to thin and change shape, this solution becomes less and less satisfactory.

Q. What is a cataract?

When proteins, naturally present in the lens of the eye, coalesce they form a cataract. In cataracts, the lens becomes opaque, vision starts to cloud, and eyesight progressively blurs. Eventually, there is no option but to remove the cataract by surgery.

A cataract can occur in one or both eyes and develops in one of the following ways:

  • Surgeons now see age-related cataracts as a normal part of ageing, and they treat around 200,000 UK patients for cataracts every year.
  • Congenital Cataracts can form at birth or in early childhood
  • Secondary Cataracts often appear after steroid use or the onset of other health conditions such as diabetes.
  • Traumatic Cataracts can form after injury to the eye, directly following either the injury or years later.

Q. What are the approaches to treating cataracts?

In the early stages, the effect of cataracts can be minimised using strong glasses, but cataract surgery will be necessary soon. As cataracts cause the lens to loose its clarity the only option is to replace it using a technique known as Intra-ocular Lens where an artificial replacement is used.

Without intervention, a sufferer from cataracts will eventually find that their eyesight will deteriorate so severely that even the strongest aids will not help. Cataract surgery is often the only alternative to loss of sight.

Q. What is glaucoma?

Glaucoma is a serious eye disease that can lead to permanent damage to the optic nerve and thus permanent blindness. Glaucoma often starts with unnoticeable blind spots, then tunnel vision, and finally complete loss of sight. There is a relationship between diabetes and open-angle glaucoma (the most common type of glaucoma), and whilst ophthalmologists do not fully understand the mechanism, all diabetics should be aware of the condition and the risks that it brings.

Ophthalmologists originally believed that pressure within the eye, intraocular pressure or IOP, was the sole cause of the optic nerve damage that causes glaucoma. Whist intraocular pressure is certainly a primary reason; experts now realise that many other factors influence the condition as people with ‘normal’ levels of pressure can experience vision loss through glaucoma.

The early detection of glaucoma is vital if a surgeon is to treat the condition successfully and most opticians now carry out glaucoma tests as a matter of course. However there is no cure and whist medication or surgery can slow or prevent further vision loss the appropriate treatment depends upon the type of glaucoma.

Whilst London Vision Clinic will readily offer advice and guidance about glaucoma, and screens all patients for glaucoma symptoms, surgery is only an option of last resort, but we do not offer it.

If you have any suspicion that you may be experiencing the symptoms of glaucoma, you should contact your doctor as soon as possible.

Browse our 101 questions and answers to gain more insight into the treatments offered at London Vision Clinic or contact one of our Patient Care Coordinators for more information.