MR ALEX BANEKE - OPHTHALMIC SURGEON - CATARACT & GLAUCOMA 07398997592 info@essexeyesurgery.co.uk
Laser Eye Surgery or Lens Replacement? How to Choose
The short answer: under 45, laser vision correction is usually the right first option. Over 50, lens replacement is frequently better. Between those ages it depends on the prescription, the cornea and how much reading difficulty has already developed.
Most people looking into life without glasses start by searching for laser eye surgery, because it is the best known option. It is an excellent operation in the right eye. But it is not the only one, and for a large group of patients, particularly those over 50 and those with strong prescriptions, it is not the best one.
This page explains the difference between the two operations, who each one suits, and what an assessment looks for.
The essential difference
The eye focuses light using two lenses, one behind the other.
The cornea is the clear window at the front. It does about two thirds of the focusing and its shape never changes much after childhood.
The natural lens sits just behind the pupil. It does the remaining third, and crucially it is the part that changes focus between distance and near. From the mid-forties it stiffens, which is why reading glasses become necessary, and in later life it clouds, which is a cataract.
Laser eye surgery reshapes the cornea. It leaves the natural lens untouched.
Lens replacement surgery removes the natural lens and replaces it with a permanent artificial one.
That single distinction explains almost everything about which operation suits whom. If the problem is the shape of the cornea, reshape the cornea. If the problem is the ageing lens, replace the lens.
Why age matters more than anything else
At 30, a short-sighted eye has a perfectly good natural lens doing its job. Removing it would throw away useful focusing ability for no reason. Laser is the obvious choice.
At 55, the same eye has a lens that has stopped changing focus, has begun to scatter light, and will need removing as a cataract within fifteen or twenty years. Reshaping the cornea in front of it deals with only part of the problem, and leaves the rest to come.
At 60, laser will correct the distance vision but the patient will still need reading glasses, will still need cataract surgery later, and the cataract surgery will be less accurate than it would have been because the cornea has been reshaped.
This is why the recommendation flips somewhere around the age of 50.
Comparison at a glance
When laser eye surgery is the better option
• Age under 45. The natural lens still focuses usefully and should be left alone. This is the single clearest indication.
• Low to moderate short-sightedness with a healthy cornea. Straightforward, safe and durable.
• Late forties with good distance vision and only reading difficulty. Laser blended vision, which sets the two eyes slightly differently to extend the range of focus, is usually preferable here. It avoids surgery inside the eye and leaves all future options open.
• Where any surgery inside the eye is best avoided, for example in a very long, highly short-sighted eye with a raised baseline risk of retinal detachment.
• A strong preference to avoid surgery inside the eye, where the patient understands and accepts that reading glasses and later cataract surgery will still be needed.
When lens replacement is the better option
• Age over 50, and particularly over 55. The natural lens has largely stopped contributing, so there is little to lose by replacing it, and by 55 the jelly inside the eye has usually separated from the retina, which reduces the risk of retinal detachment afterwards.
• One operation instead of two. Lens replacement removes the need for cataract surgery later, because an artificial lens cannot become cloudy.
• Distance and reading together. A full-range or extended-range implant addresses both. Standard laser addresses only distance.
• Prescriptions too strong for laser. There is effectively no upper limit on the prescription that a lens implant can correct.
• Corneas too thin, too irregular or too dry for laser. A substantial proportion of patients turned down at laser assessment are good candidates for lens replacement.
• Any early clouding of the natural lens. Once this has begun, laser treats the wrong structure.
• Avoiding a known problem later. Calculating the correct implant power for cataract surgery is significantly less accurate in an eye that has previously had corneal laser treatment, and those patients more often need glasses afterwards. Having the lens surgery first avoids the difficulty altogether.
More detail on the operation itself, including risks and fees: Refractive Lens Exchange in Essex.
Where implantable contact lenses fit
There is a third option that suits a particular group: a thin lens placed inside the eye alongside the natural one, without removing anything. This is usually the best choice for younger patients, typically under 45, with prescriptions too strong or corneas too thin for laser. It preserves the natural focusing ability, and it can be removed if necessary. It does not correct reading vision, and cataract surgery will still be needed in later life.
What about reading glasses?
Presbyopia, the gradual loss of close focus from the mid-forties, is the reason many people start looking into surgery in the first place. Three approaches exist.
Laser blended vision sets one eye slightly for distance and the other slightly for near, and adjusts the optics of both so the brain merges them. It works well and suits patients in their late forties and early fifties whose distance vision is otherwise good. Because the natural lens continues to age, the effect is not permanent and may need revisiting.
Extended-range or full-range implants correct distance and near in one operation and do not fade, because the ageing lens has been removed. More appropriate from 50 onwards.
Reading glasses. Still a perfectly reasonable answer, and the right one for many people.
Short-sightedness (myopia): what usually suits which age
Parents looking for treatment to slow the progression of short-sightedness in a child should search for myopia management or myopia control. That is a separate service, usually provided by specialist optometrists.
What an assessment measures
A full assessment records:
• Your prescription and whether it is stable. Please bring copies of letters from your optician with your glasses prescriptions over the past two to three years.
• The thickness and shape of the cornea, which determines whether laser is safe
• The length of the eye, which determines the risk profile of lens surgery
• The clarity of the natural lens
• The health of the retina and optic nerve
• The quality of the tear film, since dry eye affects both the measurements and the result
• How the eyes are actually used: screen distance, night driving, hobbies, occupation
Where laser or an implantable contact lens would suit better than lens replacement, that is said plainly at the consultation and an onward referral to an appropriate specialist is arranged.
Arranging an assessment
An assessment establishes which of these options suits your eyes, or whether none of them does. Private clinics with Mr Baneke are available in Southend and Brentwood, serving patients across Essex and east London.