Short-sighted before cataract surgery: should you keep your near vision?

What does 6/6 or 20/20 vision actually tell you?

6/6, or the equivalent 20/20 notation, describes how much detail you can resolve on a distance eye chart. It does not tell us whether you can read a book without glasses, see comfortably at your computer or manage glare at night.

Unaided vision is measured without glasses or contact lenses. Best-corrected vision is measured with the most suitable prescription. Someone deliberately left short-sighted may have blurred unaided distance vision but excellent distance vision with glasses. That is different from reduced vision caused by eye disease or a complication.

The aim is good visual quality and healthy eyes, with a focus that suits your life. A good distance-chart result is valuable, but it is only one part of that assessment. Cataract surgery removes the cloudy natural lens and replaces it with an artificial lens; its intended focus needs a separate discussion.

Why can short-sighted people often read without glasses?

Short-sightedness is also called myopia. An uncorrected myopic eye focuses naturally at a nearer distance. Many myopes therefore take off their distance glasses to read a phone, a book or small print. The clearest distance varies with the amount of myopia.

An eye with little or no distance prescription is called emmetropic. A young emmetropic eye can change the shape of its natural lens to bring near objects into focus. This focusing ability, called accommodation, declines with age. The resulting difficulty with near vision is presbyopia.

Myopes develop presbyopia too. Removing their distance glasses can bring their existing near focus into use; it does not reverse ageing of the lens. Someone who has never been short-sighted is more likely to rely on reading glasses as presbyopia develops.

After both eyes are targeted for distance with standard monofocal implants, the old habit of taking off your glasses to read may no longer work. The implants do not restore a young natural lens’s changing focus. This can be a significant loss for someone who valued their unaided near vision.

In focusOut of focus

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Why does holding a book closer make the print look bigger?

The same letter occupies a larger angle of your view when it is closer. Bring a page from 40 cm to 20 cm and its letters appear approximately twice as large. It is rather like moving closer to a painting to inspect the detail: the painting has not grown, but it fills more of your view.

A myopic person who can focus at that closer distance may use this effect to read fine print without a magnifier. This is magnification from viewing distance.

There are two separate requirements: the print needs to be large enough to see, and it needs to be in focus. Moving a page closer after a distance-focused lens implant may make it bigger but blurrier. Suitable near glasses can also let an emmetropic person read closer; this advantage is not exclusive to myopes.

Can cataract surgery deliberately keep some short-sightedness?

Yes. The surgeon can select a lens power intended to leave a chosen amount of myopia. This is called a myopic refractive target. It is a planned near focus, rather than an accidental failure to reach zero prescription.

As a simple optical guide, −2.00 dioptres corresponds to a focus around 50 cm, −2.50 to about 40 cm, and −3.00 to about 33 cm. Astigmatism, the implant design and eye health also affect what you can read.

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A computer screen and tiny print held close are different tasks. Mild myopia that helps at a desktop screen may not be enough for close reading. Retaining some myopia also does not mean recreating a very strong preoperative prescription.

The trade-off is distance blur without glasses. If both eyes are set for near, expect to need distance glasses for driving and other tasks needing clear distance detail. You must meet the relevant driving vision requirements with any required correction. Discuss the target for each eye, especially if only one eye is having surgery initially.

What are the main choices for distance and near vision?

Both eyes for distance: often suits people who value walking around, sport, television and driving with less dependence on glasses. With standard monofocal implants, reading glasses are usually needed. This remains an excellent choice.

Both eyes with some near focus: may suit someone who spends much of the day reading or doing detailed work and is comfortable wearing glasses for distance. A near target gives a useful range, not clear vision at every close distance.

Monovision: one eye is usually set more for distance and the other more for near. A smaller difference, sometimes called mini-monovision, may favour intermediate vision. It can reduce dependence on glasses, but some people notice imbalance or reduced depth perception. A contact-lens trial can help where feasible; it cannot exactly predict the result after removing a cataract. See monovision after cataract surgery.

EDOF or multifocal implants: extended depth of focus (EDOF) designs broaden the useful range; multifocal designs provide more than one focus. They have their own visual-quality trade-offs and may not reproduce the very close reading you enjoyed before surgery. Lens category and refractive target are separate decisions.

As explained in “Can you have your cake and eat it too?”, no implant gives everything without compromise. A well-chosen monofocal lens is a deliberate, excellent option, whether targeted for distance or near. Paying more does not automatically produce the balance you prefer.

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What does research tell us about myopic targets?

Research supports taking established reading habits seriously. An older study of people with high myopia tested different prescriptions using contact lenses and found that preferences varied: a near-focused prescription was preferred by many of those tested. It does not tell us what proportion of today’s patients should choose a near target.

A small 2024 retrospective study compared distance targets with a −2.00 dioptre target using the same enhanced monofocal implant in moderately to highly myopic patients. The near-target group had better unaided near vision and worse unaided distance vision, while corrected distance vision was similar. The groups were small, unequal and differed before surgery, with patient-selected targets and short follow-up. Overall satisfaction was lower in the near-target group, reinforcing the importance of matching expectations.

These studies illustrate the expected trade-off.  The observation in this article that most of my patients favour distance is a practice observation, rather than a population estimate. A person’s preference still needs to be considered individually.

What should you tell your surgeon before choosing a target?

Describe what you actually do with your eyes. Bring your usual glasses and, if practical, the book, phone or fine-work item that matters to you. Show how far away you hold it and whether you remove your glasses. Include computer use, hobbies, night driving and work requirements.

Be specific: “I want to read a paperback at 30 cm without glasses” is more useful than “I want perfect vision”. Decide which would bother you more: putting glasses on to read, or putting them on to see across the room. Your answer may differ from someone else’s.

The surgeon also needs to assess your cornea, astigmatism, macula and other eye conditions. High myopia can carry retinal risks that choosing a near target does not remove. A surgical target is an aim, not a guarantee; the final prescription can differ from the plan.

Ask what glasses are likely to be needed, how both eyes will work together, and what options remain if the result misses the target. Why glasses may still be needed after cataract surgery explains some of these limitations. The most useful outcome is the one that fits your daily life, rather than a distance number chosen without that conversation.

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What other questions do patients ask?

Does a near target mean accepting poorer-quality vision?

Not necessarily. It changes the focus without glasses. A healthy near-targeted eye can still have good distance vision with appropriate glasses. Eye disease, astigmatism and the implant’s optical design can separately affect visual quality.

Will keeping myopia restore my youthful near vision?

No. A near target does not restore natural accommodation or guarantee your old reading range. It can preserve a useful unaided focus, but very close work, dim light or other distances may still need glasses.

Can I choose a different target after surgery?

Glasses can alter the focus you use for particular tasks. Procedures to change the surgical result have additional risks and may not be suitable, so the initial target deserves careful discussion. Do not assume an implant can simply be changed like a pair of glasses.