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Moorfields Private Blog

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    What is ‘20/20’ vision?

    Written by Mr Alexander Ionides, Consultant Ophthalmic Surgeon
    • The 20/20 simply refers to the reading chart
    • Can perfect vision be guaranteed with laser eye surgery?

    What is 2020 vision (2)_Resized

    20/20 Vision

    Many people consider '20/20' vision to be perfect vision. The 20/20 simply refers to the reading chart that opticians and eye surgeons use to measure vision. The 20/20 line is towards the bottom of the chart, and is the level required to pass most occupational tests like those needed to become a pilot. In England we use the metric system. As 20 feet is roughly the same as 6 meters, we call 20/20 vision 6/6 vision.

    Can you guarantee perfect vision with laser eye surgery?

    The vast majority of people undergoing laser eye surgery will enjoy 6/6 vision or better. That said, it depends on what your vision was like prior to laser eye surgery, and also what your prescription is.

    Short-sighted people who are -6.00 or less are more likely to be 6/6 or better after a single laser vision correction treatment. Most people with higher prescriptions also get to the 6/6 level after a single treatment, but enhancement treatments are more likely to be required for stronger prescriptions. Overall, less than 5% of patients treated at Moorfields Private need an enhancement treatment.

    These second treatments are low-risk and are normally performed three to six months after the initial treatment. There are no guarantees in any medical procedure. Only odds of success. The good news for laser vision correction is that most patients see at least what they saw in soft contact lenses after treatment, and sometimes better. If you start out being able to see 6/6 in glasses, the chances are you will finish with at least this level of vision after laser vision correction. 

    Read more about what to expect when you have laser eye surgery

    Results from implant-based techniques, such as ICL (Implantable Contact Lenses), are also very good. Our surgeons will discuss which technique is most suitable for you, and advise you if there are any special areas of your eye health that might affect your vision after treatment.

    Or speak to the New Patient Enquiry Team:

    0800 328 3421



    Mr Alexander Ionides

    Written by Mr Alexander Ionides

    Consultant Ophthalmic Surgeon