Continuing from yesterday:
Some surgeons recommend PRK or LASEK (both forms of surface laser eye treatment and basically the same) over LASIK. The article referred to by Kay in her original post and advocating LASEK was written by ophthalmic surgeon Sunil Shah, who was one of the creators of that particular approach (and so has some personal interest in writing about it one presumes).

One of the very vocal and respected advocates of surface laser (PRK) over keratome LASIK was Professor John Marshall in London, UK, a founding father of laser eye surgery back in the 80s. Prof Marshall argued convincingly that the cornea was considerable stronger after PRK compared to mechanical (thicker flap) keratome LASIK.

However, the game has changed with the introduction of femtosecond lasers with much thinner flaps. Even Professor Marshall now supports the move to thin-flap LASIK using a dual laser, blade-free approach.

So if a clinic cannot offer dual laser LASIK (and many still can’t) they may offer PRK/LASEK instead. There are some clinical reasons to perform PRK instead of LASIK but the percentage of these cases has shrunk from 10-15% down to around 5% today, with dual laser technology. Patients much prefer femto-laser LASIK over PRK, as the latter is fairly unpleasant for a few days post-op.

In summary, there are definite clinical reasons why we as treating clinics have moved over to wavefront LASIK and using a blade-free dual laser approach. More accurate treatments so better vision, removal of an older mechanical device technology and improved long-term safety.

We discussed in the last post about the two options you have: LASIK or PRK (surface laser), and how 90%+ of treatments are done via LASIK.

LASIK comes in two flavours now: blade or blade-free. The older traditional LASIK technique uses a mechanical device containing a blade (called a keratome or microkeratome) to cut a flap during the first part of the procedure. The newer, more advanced method is to use a special laser (known as a femtosecond laser) to create a flap without a blade.

These femtosecond lasers are hugely expensive (about a quarter of a millions pounds each!) so expect to pay more for this technology. Some clinics have not yet invested in femto lasers due to the high cost involved and continue to use a blade.

The benefits of a laser flap over a blade flap are becoming clear: more accurate treatment, better healing of the flap, greater strength in the cornea post-op due to significantly thinner laser flaps and greater residual thickness. Blade flaps have been used for many years and have been proven safe to date, but thinner laser flaps have added better accuracy and strength. You will see a gradual phasing out of blade flaps over laser flaps over the coming few years.

More tomorrow!

If you read yesterdays post you are up to speed on wavefront technology. OK, so far so good. It seems wavefront correction improves quality of vision after laser eye surgery. And indeed clinical trials confirm that vision results are much better after laser makers added the ‘wavefront‘ upgrades to their machines.

For example, the American made VISX lasers, used at all Optical Express laser clinics, have much better results when using their wavefront upgrade from 2002. I would not recommend having laser eye treatment today in 2008 without choosing the wavefront package on that system.

Wavefront laser eye surgery - is it the whole truth?

So now you want ‘wavefront‘ in your laser eye treatment! Of course, as the results are better. But when laser manufacturers introduced ‘wavefront’ they actually bundled in other improvements which may account for much of the jump in results! They just didn’t tell you. Why? Because it is complicated to describe all these improvements to someone who isn’t familiar with the technology – such as you, the patient!!

And honestly, I bet the sales people at most clinics talking on the phones who want to sell you a consultation don’t really understand it either! However, they have been trained to explain the wavefront part only, as something like this… “we take a scan, a unique fingerprint, of your vision and the use that fingerprint to perfectly correct your vision“. Go on, call them and check it out!

But for you, as a patient or customer, don’t really care about which part of that technology is helping you the most, you just want great vision, right?

So don’t let clinics blind you with science about wavefront scanners, wavefront maps, measuring hundreds of points of light or how much better their scanner is than other clinics scanners. It is usually marketing spin! Take it all with a pinch of salt.

However, you should choose the ‘wavefront option’ because within that package are the big improvements in laser eye treatment over the past several years. The success of surgery may actually be less to do with the true wavefront technology that has helped astronomy, but rather other improvements that may be confusing to patients but get wrapped up in the marketing of wavefront LASIK.

We come back to ethics again here. Is it ethical for some clinics to still sell ‘non-wavefront’ laser eye surgery technology that was replaced back in 2002?

For my own clinic, we do not offer non-wavefront treatments at all. None at all. I want every one of my patients to have the benefit of the newer laser eye surgery results. So we made it very affordable. In fact, we charge less for wavefront LASIK than other clinics do for their ‘entry level’ lower price non-wavefront LASIK. Really.

That’s my plug for FOCUS done! So, do choose wavefront but don’t pay more than you have to!

_{»crosslinked«}

To recap from earlier this week, there are two ways you can upgrade your laser eye treatment: (1) upgrading on the quality of the final vision (you will see better afterwards) and (2) improving the safety and accuracy of the laser eye surgery. These are upgrades on what used to be the best treatment only a few years ago, which is known as non-wavefront LASIK and using a blade device to cut a thin flap in the surface of the cornea (the clear window at the front of the eye).

Upgrading on (1) involves paying for what is called ‘wavefront‘ laser eye surgery over ‘non-wavefront’.

Upgrading on (2) means getting rid of a metal razor-type blade in favour of a laser for the first part of the LASIK treatment (lots of names here… blade-free, dual laser, femtosecond, Intralase, Ziemer, Z-LASIK).

Kay’s questions have been about: is it really worth it to pay more? The short answer is that, yes, you should always look for ‘wavefront’ laser eye treatment. But why?

Well, the reason for this is not as obvious as laser eye clinics may tell you!

Wavefront refers to a technology adapted from astronomy which allows better resolution and clarity when looking at images of space. The principle is to remove tiny imperfections of focus, rays of light that are not getting focused properly and which cause blurriness, glare or hide details. Let’s look at an example from astronomy. In this image you can see how a blurry image of a star was improved though wavefront technology to reveal in fact two stars, known as a ‘binary star’.

'Wavefront' laser eye surgery can improve quality of vision

These imperfections of focus (known usually as aberrations) are not corrected by glasses. They are still there even after putting on your glasses or contact lenses. So after correcting your prescription fully and getting clear vision, you can still have imperfections in your vision which are usually more obvious at night.

Check back tomorrow for the next installment and the full answer on whether it is worth it to pay more  in order to get the best vision results (at most clinics – not mine, I add, FOCUS Laser Vision! – we don’t charge extra for you to get wavefront correction! In fact we charge less for wavefront surgery than other clinics do for their non-wavefront treatments).

See you tomorrow!

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.

TECHNOLOGY that has become available over past two years means that reading vision problems can now be very effectively addressed through laser eye treatment. Although at present only a few clinics specialise in this area, it is the fasting growing section of the laser vision arena.

FOCUS Laser Vision specialises in the correction of loss of reading vision, either through advanced LASIK laser eye surgery or through the use of lenses inside the eye (IOLs)

Several approaches to LASIK are showing promise in the treatment of reading vision problems (presbyopia) for patients with otherwise normal distance vision, or long or short sight, according to studies presented at the 12th Winter Refractive Meeting of the ESCRS.

In research presented by Kenneth A Greenberg MD, all patients achieved good distance vision of 20/25 or better and were able to read telephone directory sized print, 12 months after undergoing customised LASIK treatments. The multicentre study involved 28 presbyopic long-sighted patients with an average age of 56 years.

WaveLight AG, based in Erlangen, Germany [who make the excellent Allegretto eye laser] increased its sales for the first nine months of 2007/8 accounting year by 31% to €65 million. The previous year’s turnover was €49.5 million for the same period.

The company’s market position in the U.S. has also expanded. In the worldwide sales-strong US market, which has been of great importance for WaveLight for the refractive surgery area, the company exceeded the turnover of the comparable period in the previous year by 66%.

WaveLight make the Allegretto Eye-Q 400 Hz excimer system for laser eye surgery. You can see the FDA results for the WaveLight laser versus other systems here.

Leading ophthalmologists plus LASIK patients at the Food and Drug Administration (FDA) Ophthalmic Devices Advisory Panel (ODP) presented two conflicting perspectives on the LASIK laser eye surgery procedure last week.

After hearing data and moving stories from both sides, the action taken was a number of recommendations on how to improve patient labeling of eye lasers and the FDA’s LASIK website page; how the FDA should recognize the American National Standards Institute’s (ANSI) standard for laser systems for corneal reshaping (Z80.11); and possible amendments for a list of LASIK-related adverse events for self-monitoring of the procedure.

After hearing stories from dissatisfied LASIK patients, Jayne S. Weiss, M.D., professor & Director of Refractive Surgery and Ophthalmic Pathology, Kresge Eye Institute, Wayne State University, Detroit plus ODP acting chairwoman, noted that while the stories are important the panel’s goal is to see the big picture. “Individual stories are compelling, but we need to put it into context,” said Dr. Weiss.