Here are the answers to one of today’s questions:

From Ian, who said:

A fantastic site, very informative.  A quick (but naive) question.  I am very excited about the prospect of having intra Lasik to correct a minus 5 prescription.  However, I have read some scare stories on US web sites which suggest that it is possible that the cornea can be irreparably damaged during the flap creation process.  How often have you seen this happen?

Thanks Ian. Correcting a -5.00D prescription is quite routine and should give you no problems. You mentioned IntraLASIK, which is a brand name when the Intralase femtosecond laser is used to create a Lasik flap. I don’t know whether you refer to femtosecond Lasik in general or you are looking at the Intralase machine for treatment. Manufacturers AMO now refer to iLasik rather than IntraLASIK. Other version are Z-LASIK when the Ziemer femtosecond laser is used, and Visumax and Femtec systems from other companies.

The femtosecond lasers have replaced the blade-cut keratome Lasik procedures in many clinics. One of the reasons to do this is to eliminate the possibility of a seriously damaged flap from a keratome, which I have seen happen (although it’s occurrence is rare). I have never seen this occur with a femtosecond laser and it is not possible to ‘mangle’ a flap with these technologies, so added safety.

WHENEVER a patient undergoes any type of surgical treatment there is a possibility for a complication. The main questions are: are these complications serious and could affect the final outcome – or minor and short lived and which do not affect the ultimate vision? Also, what are the chances of a complication occurring that would require adjustment or follow-up correction?

LASIK surgery is no different from any other operation, despite how it may be pitched by some clinics, in that it IS a surgical correction and should be approached as such. However, and fortunately, most complications are in fact minor and easily resolved.

Technology

LASIK risk continues to drop as doctors and engineers perfect the equipment used in the treatment. Advances in technology have made a big part of the difference here so make sure you are getting that latest equipment and not an older fashioned approach.

The risks drop as doctors continue to screen for the right candidates to have the procedure, and screen out those with any chance to have a problem. Research also shows that with the right pre-testing and surgical handling, the risk of complications in LASIK surgery is less than 1% and most of these are minor problems which will be fully corrected afterwards without undue ongoing problems.

The most common risk with LASIK surgery is a complication with the flap, created by the surgeon in the first part of the procedure.

In the original LASIK procedure, the flap is cut by a surgical blade device known as a microkeratome. The blade cut is, however, less precise than those from newer femtosecond lasers.

Blade Free LASIK

LASIK risk is reduced by the newer “bladeless” dual laser technique.

In bladeless (blade free) LASIK surgery, the risk of complications is lower because the blade or microkeratome is no longer used. It is replaced by special type of infra-red laser that greatly reduces human or machine error.

The original laser to make a LASIK flap came from the USA, manufactured by Intralase. You may see this surgery called IntraLASIK or iLASIK.

The newer machine is from Switzerland and produced by the Ziemer Group of companies. There appear to be some advantages of the tighter focus of the Swiss laser. This procedure may be called Z-LASIK.

Summary

When assessing these LASIK risks it is recommended that when you are considering surgery that you ask your doctor what technology the clinic has and whether or not a blade free dual laser approach will be used.

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A new lens to help reading vision has received approval from the American Food & Drug Administration (FDA), according to manufacturers Bausch & Lomb, based at Rochester in New York state.

These lenses are inserted inside the eye during a procedure very similar to that used for cataract surgery. The natural lens is removed and replaced with an artificial intraocular lens (IOL). The traditional IOL has a fixed focus and is unable to replicate the natural flexibility of the young human lens that allows us to zoom in on near objects to have clear close vision, e.g. reading a newspaper print.

Accommodating lenses are designed to mimic the natural zoom ability to not only provide clear distance vision but also to restore good near vision. This loss of near vision with age is called ‘presbyopia‘ and affects 20 million people in the UK alone.

The Crystalens HD is designed for enhanced depth of focus and features something called “proprietary optical focus,” B&L stated in a press release. This optical ability is claimed to be capable of improving near vision without reducing distance or intermediate vision. In the research study from B&L, 125 eyes were implanted with the new Crystalens HD. These patients had a visually significant cataract (usually age related clouding of the lens inside the eye), less than 1 D of corneal astigmatism, and the potential for best corrected visual acuity of 20/25 or better in both eyes. Of this study population, four out of five patients (80%) had vision of J2 (equivalent to small ingredients lists on food packets) or better at 4 months. B&L said it plans to begin sending out the Crystalens HD in early July.