How effective are the results? : Laser Eye Surgery
The effectiveness of the results depend on a number of factors including the expertise, experience and skill of the surgeon, the type of laser and other equipment they utilize to carry out the procedure, and the pre-operative severity of the eyes’ refractive defect.
Best case scenario
Patients with myopia or nearsightedness in the range of -2.50 to -4.00 diopter usually experience the best overall results in terms of the difference between pre- and post-operative vision. This degree of myopia falls in the low to medium range, with low myopia classified as between -1.00 and -3.00 diopter, and medium from -3.00 to -6.00.
Wavefront Technology
The equipment used is also a crucial factor in obtaining the best results, as shown when the clinic offers wavefront technology as part of their laser treatment. Basically this allows greater precision of the laser by finding out your individual wavefront pattern. The pattern shows how light passes through your eye, which is idiosyncratic to each of us. An Aberrometer can detect these patterns and build an accurate map which, with the help of computer software, will help to guide the laser. Greater visual improvement has been documented when the surgeon implements this technology.
If wavefront technology is used to correct myopia between -2.50 and -4.00 diopter, the percentage of people who will gain driving standard vision is estimated to be in the high nineties. Some people even find that they their vision is better than 20/20, allowing them to see clearer than they did with glasses or contact lenses.
Hyperopia and greater severity
Those patients with hyperopia or farsightedness report less success on average, with the percentage of those who achieve a driving standard of eyesight dropping into the mid-eighties. It is also true that the greater the severity of visual impairment, the less reliable or at least predictable the results may be. Most laser eye surgeons will treat up to +5.00 (for hyperopia) or -10.00 (for myopia) diopters, as suitable correction after this point is not assured.
The likelihood of a patient ending up with poorer vision than prior to the surgery is relatively low, but 1 in 10000 patients can experience this unfortunate result. In these cases, sometimes the patient’s vision is affected to the extent that even wearing contact lenses or glasses (at a higher prescription than before) can fail to fully restore their vision. Seeking further laser surgery can sometimes be effective in tackling the problem.
Presbyopia
Presbyopia is the farsightedness that evolves naturally as a product of advancing age. It is not linked to the cornea and therefore cannot be treated by laser eye surgery, though there are some non-laser treatments on the market. Natural presbyopia means that people who have laser surgery prior to the age of 40 will at some point develop the condition and require reading glasses.